U.S. patent application number 14/932268 was filed with the patent office on 2016-05-26 for hydroprocessing for distillate production.
This patent application is currently assigned to ExxonMobil Research and Engineering Company. The applicant listed for this patent is Joseph Ernest BAUMGARTNER, Doron LEVIN, Sabato MISEO, Stuart Leon SOLED, Keith WILSON, Xiaochun XU. Invention is credited to Joseph Ernest BAUMGARTNER, Doron LEVIN, Sabato MISEO, Stuart Leon SOLED, Keith WILSON, Xiaochun XU.
Application Number | 20160145503 14/932268 |
Document ID | / |
Family ID | 56009563 |
Filed Date | 2016-05-26 |
United States Patent
Application |
20160145503 |
Kind Code |
A1 |
XU; Xiaochun ; et
al. |
May 26, 2016 |
HYDROPROCESSING FOR DISTILLATE PRODUCTION
Abstract
Methods are provided for hydrotreating a feed to generate a
product with a reduced or minimized aromatics content and/or an
increased distillate product yield. A distillate boiling range feed
having an elevated content of sulfur and/or nitrogen can be
hydrotreated using at least two hydrotreating stages with
intermediate separation to produce a hydrotreated distillate
boiling range product with a reduced or minimized aromatics
content. Additionally or alternately, a mixed metal catalyst formed
from a suitable precursor can be used during the hydrotreating. A
mixed metal catalyst formed from a suitable precursor can provide
an unexpectedly superior activity for aromatic saturation. A still
further unexpected benefit can be achieved by combining a
multi-stage hydrotreating process with intermediate separation with
hydrotreating in the presence of a mixed metal catalyst formed from
a suitable precursor.
Inventors: |
XU; Xiaochun; (Sugar Land,
TX) ; WILSON; Keith; (Weybridge, GB) ; SOLED;
Stuart Leon; (Pittstown, NJ) ; MISEO; Sabato;
(Pittstown, NJ) ; LEVIN; Doron; (Highland Park,
NJ) ; BAUMGARTNER; Joseph Ernest; (Califon,
NJ) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
XU; Xiaochun
WILSON; Keith
SOLED; Stuart Leon
MISEO; Sabato
LEVIN; Doron
BAUMGARTNER; Joseph Ernest |
Sugar Land
Weybridge
Pittstown
Pittstown
Highland Park
Califon |
TX
NJ
NJ
NJ
NJ |
US
GB
US
US
US
US |
|
|
Assignee: |
ExxonMobil Research and Engineering
Company
Annandale
NJ
|
Family ID: |
56009563 |
Appl. No.: |
14/932268 |
Filed: |
November 4, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62082273 |
Nov 20, 2014 |
|
|
|
62152083 |
Apr 24, 2015 |
|
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|
62152092 |
Apr 24, 2015 |
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Current U.S.
Class: |
208/57 ; 208/143;
208/145 |
Current CPC
Class: |
C10G 45/08 20130101;
B01J 23/882 20130101; C10G 69/02 20130101; C10G 65/12 20130101;
C10G 2300/1048 20130101; C10G 65/08 20130101; C10G 2300/202
20130101; C10G 65/04 20130101; B01J 37/20 20130101; C10G 47/06
20130101; C10G 2300/301 20130101; B01J 23/888 20130101; C10M 101/02
20130101; C10G 35/06 20130101; B01J 23/8885 20130101; C10G 69/08
20130101; C10G 45/50 20130101; C10G 65/02 20130101; B01J 23/883
20130101; C10G 2400/00 20130101; C10G 67/04 20130101 |
International
Class: |
C10G 45/50 20060101
C10G045/50; C10G 69/08 20060101 C10G069/08; C10G 69/02 20060101
C10G069/02; C10G 35/06 20060101 C10G035/06; C10G 65/08 20060101
C10G065/08 |
Claims
1. A hydrotreatment process comprising: reacting a feedstream, the
feedstream having a sulfur content of about 500 wppm to about 50000
wppm and an aromatics content of at least about 60 wt %, in the
presence of a hydrogen-containing treat gas and in the presence of
a mixed metal catalyst under effective hydrotreating conditions for
converting about 5 wt % or less of the feedstream relative to a
conversion temperature of 350.degree. F. (177.degree. C.); and
separating the first liquid effluent to produce a vapor phase
stream and a liquid product stream, the liquid product stream
having a sulfur content of about 500 wppm or less, wherein the
mixed metal catalyst comprises a sulfided mixed metal catalyst
formed by sulfiding a mixed metal catalyst precursor composition,
the mixed metal catalyst precursor composition being produced by a)
heating a composition comprising at least one metal from Group 6 of
the Periodic Table of the Elements, at least one metal from Groups
8-10 of the Periodic Table of the Elements, and a reaction product
formed from (i) a first organic compound containing at least one
amine group, and (ii) a second organic compound separate from said
first organic compound and containing at least one carboxylic acid
group to a temperature from about 195.degree. C. to about
260.degree. C. for a time sufficient for the first and second
organic compounds to form a reaction product in situ that contains
an amide moiety, unsaturated carbon atoms not present in the first
or second organic compounds, oxygen atoms not present in the first
or second organic compounds, or a combination thereof; b) heating a
composition comprising one metal from Group 6 of the Periodic Table
of the Elements, at least one metal from Groups 8-10 of the
Periodic Table of the Elements, and a reaction product formed from
(iii) a first organic compound containing at least one amine group
and at least 10 carbon atoms or (iv) a second organic compound
containing at least one carboxylic acid group and at least 10
carbon atoms, but not both (iii) and (iv), wherein the reaction
product contains additional unsaturated carbon atoms, relative to
(iii) the first organic compound or (iv) the second organic
compound, wherein the metals of the catalyst precursor composition
are arranged in a crystal lattice, and wherein the reaction product
is not located within the crystal lattice, to a temperature from
about 195.degree. C. to about 260.degree. C. for a time sufficient
for the first or second organic compounds to form a reaction
product in situ that contains unsaturated carbon atoms not present
in the first or second organic compounds, oxygen atoms not present
in the first or second organic compounds, or a combination thereof;
or c) heating a composition comprising at least one metal from
Group 6 of the Periodic Table of the Elements, at least one metal
from Groups 8-10 of the Periodic Table of the Elements, and a
pre-formed amide formed from (v) a first organic compound
containing at least one amine group, and (vi) a second organic
compound separate from said first organic compound and containing
at least one carboxylic acid group, to form at least one of
additional in situ unsaturated carbon atoms or in situ added oxygen
atoms not present in the first organic compound, the second organic
compound, or both, but not for so long that the pre-formed amide
substantially decomposes, thereby forming a catalyst precursor
containing at least one of in situ formed unsaturated carbon atoms
or in situ added oxygen atoms.
2. The process of claim 1, wherein reacting the feedstream in the
presence of a mixed metal catalyst further comprises reacting the
feedstream in the presence of one or more additional hydrotreating
catalysts, the one or more additional hydrotreating catalysts and
the mixed metal catalyst optionally comprising a catalyst mixture,
or the one or more additional hydrotreating catalysts and the mixed
metal catalyst optionally comprising a stacked bed of catalysts, or
the one or more additional hydrotreating catalysts and the mixed
metal catalyst optionally being located in separate catalyst beds,
or a combination thereof.
3. The process of claim 1, wherein the effective hydrotreating
conditions comprise temperatures of about 200.degree. C. to about
450.degree. C.; pressures of about 250 psig (1.8 MPag) to about
5000 psig (34.6 MPag); liquid hourly space velocities (LHSV) of
about 0.1 hr.sup.-1 to about 10 hr.sup.-1; and hydrogen treat rates
of about 200 scf/B (35.6 m.sup.3/m.sup.3) to about 10,000 sc/B
(1781 m.sup.3/m.sup.3).
4. The process of claim 1, wherein the feedstream has a multi-ring
aromatics content of at least about 40 wt %.
5. The process of claim 1, wherein the catalyst precursor
composition is treated first with said first organic compound and
second with said second organic compound, or wherein the catalyst
precursor composition is treated first with said second organic
compound and second with said first organic compound, or wherein
the catalyst precursor composition is treated simultaneously with
said first organic compound and with said second organic
compound.
6. The process of claim 1, wherein said at least one metal from
Group 6 is Mo, W, or a combination thereof, and wherein said at
least one metal from Groups 8-10 is Co, Ni, or a combination
thereof.
7. The process of claim 1, wherein the mixed metal catalyst
precursor composition is a bulk metal hydroprocessing catalyst
precursor composition consisting essentially of the reaction
product, an oxide form of the at least one metal from Group 6, an
oxide form of the at least one metal from Groups 8-10, and
optionally about 20 wt % or less of a binder.
8. The process of claim 1, wherein a T10 boiling point of the
feedstream is at least about 350.degree. F. (177.degree. C.), or
wherein the T90 boiling point of the feedstream is about
850.degree. F. (454.degree. C.) or less, or a combination
thereof.
9. The process of claim 1, further comprising performing catalytic
dewaxing, hydrofinishing, aromatic saturation, or a combination
thereof on at least a portion of the liquid product stream or on at
least a portion of the second liquid product stream.
10. A multistage hydroprocessing process comprising: reacting a
feedstream having a sulfur content of at least about 3000 wppm in a
first hydroprocessing stage in the presence of a
hydrogen-containing treat gas and in the presence of at least one
first stage hydroprocessing catalyst, the first hydroprocessing
stage being operated at first stage hydroprocessing conditions,
thereby resulting in a first liquid effluent having a sulfur
content of about 3000 wppm or less; separating at least a portion
of the first liquid effluent to produce a first vapor phase stream
and a first liquid product stream; reacting at least a portion of
the first liquid product stream in a second hydroprocessing stage
in the presence of a hydrogen-containing treat gas and a mixed
metal catalyst, the second hydroprocessing stage being operated at
second stage hydroprocessing conditions to produce a second liquid
effluent; and separating at least a portion of the second liquid
effluent to produce a second vapor phase stream and a second liquid
product stream having a sulfur content of about 500 wppm or less,
wherein the mixed metal catalyst comprises a sulfided mixed metal
catalyst formed by sulfiding a mixed metal catalyst precursor
composition, the mixed metal catalyst precursor composition being
produced by a) heating a composition comprising at least one metal
from Group 6 of the Periodic Table of the Elements, at least one
metal from Groups 8-10 of the Periodic Table of the Elements, and a
reaction product formed from (i) a first organic compound
containing at least one amine group, and (ii) a second organic
compound separate from said first organic compound and containing
at least one carboxylic acid group to a temperature from about
195.degree. C. to about 260.degree. C. for a time sufficient for
the first and second organic compounds to form a reaction product
in situ that contains an amide moiety, unsaturated carbon atoms not
present in the first or second organic compounds, oxygen atoms not
present in the first or second organic compounds, or a combination
thereof; b) heating a composition comprising one metal from Group 6
of the Periodic Table of the Elements, at least one metal from
Groups 8-10 of the Periodic Table of the Elements, and a reaction
product formed from (iii) a first organic compound containing at
least one amine group and at least 10 carbon atoms or (iv) a second
organic compound containing at least one carboxylic acid group and
at least 10 carbon atoms, but not both (iii) and (iv), wherein the
reaction product contains additional unsaturated carbon atoms,
relative to (iii) the first organic compound or (iv) the second
organic compound, wherein the metals of the catalyst precursor
composition are arranged in a crystal lattice, and wherein the
reaction product is not located within the crystal lattice, to a
temperature from about 195.degree. C. to about 260.degree. C. for a
time sufficient for the first or second organic compounds to form a
reaction product in situ that contains unsaturated carbon atoms not
present in the first or second organic compounds, oxygen atoms not
present in the first or second organic compounds, or a combination
thereof; or c) heating a composition comprising at least one metal
from Group 6 of the Periodic Table of the Elements, at least one
metal from Groups 8-10 of the Periodic Table of the Elements, and a
pre-formed amide formed from (v) a first organic compound
containing at least one amine group, and (vi) a second organic
compound separate from said first organic compound and containing
at least one carboxylic acid group, to form at least one of
additional in situ unsaturated carbon atoms or in situ added oxygen
atoms not present in the first organic compound, the second organic
compound, or both, but not for so long that the pre-formed amide
substantially decomposes, thereby forming a catalyst precursor
containing at least one of in situ formed unsaturated carbon atoms
or in situ added oxygen atoms.
11. The process of claim 10, wherein the first liquid effluent has
a sulfur content of at least about 1000 wppm.
12. The process of claim 10, further comprising hydroprocessing at
least a portion of the first liquid product stream in an
intermediate hydrotreating stage.
13. The process of claim 10, wherein the feedstream has an
aromatics content of at least about 60 wt %.
14. The process of claim 10, wherein the feedstream has a
multi-ring aromatics content of at least about 40 wt %.
15. The process of claim 10, wherein the catalyst precursor
composition is treated first with said first organic compound and
second with said second organic compound, or wherein the catalyst
precursor composition is treated first with said second organic
compound and second with said first organic compound, or wherein
the catalyst precursor composition is treated simultaneously with
said first organic compound and with said second organic
compound.
16. The process of claim 10, wherein the first stage
hydroprocessing conditions, the second stage hydroprocessing
conditions, or both the first stage and the second stage
hydroprocessing conditions comprise effective hydroprocessing
conditions, the effective hydroprocessing conditions comprising
temperatures of about 200.degree. C. to about 450.degree. C.;
pressures of about 250 psig (1.8 MPag) to about 5000 psig (34.6
MPag); liquid hourly space velocities (LHSV) of about 0.1 hr.sup.-1
to about 10 hr.sup.-1; and hydrogen treat rates of about 200 scf/B
(35.6 m.sup.3/m.sup.3) to about 10,000 scf/B (1781
m.sup.3/m.sup.3), the first stage and second stage hydroprocessing
conditions optionally but preferably being selected
independently.
17. The process of claim 10, wherein the first stage hydrotreating
conditions are effective for conversion of about 10 wt % or less of
the feedstream relative to a conversion temperature of about
350.degree. F. (177.degree. C.), or wherein the second stage
hydrotreating conditions are effective for conversion of about 10
wt % or less of the feedstream relative to a conversion temperature
of about 350.degree. F. (177.degree. C.), or wherein about 10 wt %
or less of the feedstream is converted relative to a conversion
temperature of 350.degree. F. (177.degree. C.) during the reacting
in the first hydrotreating stage and the second hydrotreating
stage, or a combination thereof.
18. The process of claim 10, wherein a T90 boiling point of the
first liquid product stream is about 800.degree. F. (427.degree.
C.) or less.
19. The process of claim 10, wherein a T10 boiling point of the
feedstream is at least about 350.degree. F. (177.degree. C.), or
wherein the T90 boiling point of the feedstream is about
850.degree. F. (454.degree. C.) or less, or a combination
thereof.
20. A multistage hydroprocessing process comprising: reacting a
feedstream in a first hydroprocessing stage in the presence of a
hydrogen-containing treat gas, the first stage containing one or
more reaction zones, each reaction zone operated at first stage
hydroprocessing conditions and in the presence of a first
hydroprocessing catalyst, thereby resulting in a first liquid
effluent; separating at least a portion of the first liquid
effluent to produce a first vapor phase stream and a first liquid
product stream, the first liquid product stream having a sulfur
content of about 1000 wppm to about 5000 wppm; reacting at least a
portion of the first liquid product stream in a second
hydroprocessing stage in the presence of a hydrogen-containing
treat gas, the second hydroprocessing stage containing at least one
reaction zone operated at second stage hydroprocessing conditions,
the at least one reaction zone containing a mixed metal
hydroprocessing catalyst, thereby resulting in a second liquid
effluent; and separating at least a portion of the second liquid
effluent to produce a second vapor phase stream and a second liquid
product stream, the second liquid product stream having a sulfur
content of about 100 wppm or less; wherein the mixed metal catalyst
comprises a sulfided mixed metal catalyst formed by sulfiding a
mixed metal catalyst precursor composition, the mixed metal
catalyst precursor composition being produced by a) heating a
composition comprising at least one metal from Group 6 of the
Periodic Table of the Elements, at least one metal from Groups 8-10
of the Periodic Table of the Elements, and a reaction product
formed from (i) a first organic compound containing at least one
amine group, and (ii) a second organic compound separate from said
first organic compound and containing at least one carboxylic acid
group to a temperature from about 195.degree. C. to about
260.degree. C. for a time sufficient for the first and second
organic compounds to form a reaction product in situ that contains
an amide moiety, unsaturated carbon atoms not present in the first
or second organic compounds, oxygen atoms not present in the first
or second organic compounds, or a combination thereof; b) heating a
composition comprising one metal from Group 6 of the Periodic Table
of the Elements, at least one metal from Groups 8-10 of the
Periodic Table of the Elements, and a reaction product formed from
(iii) a first organic compound containing at least one amine group
and at least 10 carbon atoms or (iv) a second organic compound
containing at least one carboxylic acid group and at least 10
carbon atoms, but not both (iii) and (iv), wherein the reaction
product contains additional unsaturated carbon atoms, relative to
(iii) the first organic compound or (iv) the second organic
compound, wherein the metals of the catalyst precursor composition
are arranged in a crystal lattice, and wherein the reaction product
is not located within the crystal lattice, to a temperature from
about 195.degree. C. to about 260.degree. C. for a time sufficient
for the first or second organic compounds to form a reaction
product in situ that contains unsaturated carbon atoms not present
in the first or second organic compounds, oxygen atoms not present
in the first or second organic compounds, or a combination thereof;
or c) heating a composition comprising at least one metal from
Group 6 of the Periodic Table of the Elements, at least one metal
from Groups 8-10 of the Periodic Table of the Elements, and a
pre-formed amide formed from (v) a first organic compound
containing at least one amine group, and (vi) a second organic
compound separate from said first organic compound and containing
at least one carboxylic acid group, to form at least one of
additional in situ unsaturated carbon atoms or in situ added oxygen
atoms not present in the first organic compound, the second organic
compound, or both, but not for so long that the pre-formed amide
substantially decomposes, thereby forming a catalyst precursor
containing at least one of in situ formed unsaturated carbon atoms
or in situ added oxygen atoms.
21. A hydrotreatment process comprising: reacting a naphtha boiling
range feedstream comprising a cracked naphtha portion in the
presence of a hydrogen-containing treat gas and in the presence of
a mixed metal catalyst under effective hydrotreating conditions;
and separating the first liquid effluent to produce a vapor phase
stream and a liquid product stream, the liquid product stream
having a sulfur content of about 100 wppm or less, wherein the
mixed metal catalyst comprises a sulfided mixed metal catalyst
formed by sulfiding a mixed metal catalyst precursor composition,
the mixed metal catalyst precursor composition being produced by a)
heating a composition comprising at least one metal from Group 6 of
the Periodic Table of the Elements, at least one metal from Groups
8-10 of the Periodic Table of the Elements, and a reaction product
formed from (i) a first organic compound containing at least one
amine group, and (ii) a second organic compound separate from said
first organic compound and containing at least one carboxylic acid
group to a temperature from about 195.degree. C. to about
260.degree. C. for a time sufficient for the first and second
organic compounds to form a reaction product in situ that contains
an amide moiety, unsaturated carbon atoms not present in the first
or second organic compounds, oxygen atoms not present in the first
or second organic compounds, or a combination thereof; b) heating a
composition comprising one metal from Group 6 of the Periodic Table
of the Elements, at least one metal from Groups 8-10 of the
Periodic Table of the Elements, and a reaction product formed from
(iii) a first organic compound containing at least one amine group
and at least 10 carbon atoms or (iv) a second organic compound
containing at least one carboxylic acid group and at least 10
carbon atoms, but not both (iii) and (iv), wherein the reaction
product contains additional unsaturated carbon atoms, relative to
(iii) the first organic compound or (iv) the second organic
compound, wherein the metals of the catalyst precursor composition
are arranged in a crystal lattice, and wherein the reaction product
is not located within the crystal lattice, to a temperature from
about 195.degree. C. to about 260.degree. C. for a time sufficient
for the first or second organic compounds to form a reaction
product in situ that contains unsaturated carbon atoms not present
in the first or second organic compounds, oxygen atoms not present
in the first or second organic compounds, or a combination thereof;
or c) heating a composition comprising at least one metal from
Group 6 of the Periodic Table of the Elements, at least one metal
from Groups 8-10 of the Periodic Table of the Elements, and a
pre-formed amide formed from (v) a first organic compound
containing at least one amine group, and (vi) a second organic
compound separate from said first organic compound and containing
at least one carboxylic acid group, to form at least one of
additional in situ unsaturated carbon atoms or in situ added oxygen
atoms not present in the first organic compound, the second organic
compound, or both, but not for so long that the pre-formed amide
substantially decomposes, thereby forming a catalyst precursor
containing at least one of in situ formed unsaturated carbon atoms
or in situ added oxygen atoms.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional
Application Ser. No. 62/082,273, filed Nov. 20, 2014, U.S.
Provisional Application Ser. No. 62/152,083 filed Apr. 24, 2015,
and U.S. Provisional Application Ser. No. 62/152,092, filed Apr.
24, 2015, herein incorporated by reference in their entirety.
FIELD
[0002] Systems and methods are provided for processing distillate
boiling range feeds for production of distillate boiling range
products.
BACKGROUND
[0003] As methods for recovering natural gas from shale formations
and other non-conventional sources have improved, the cost of using
natural gas has decreased. This reduction in natural gas cost means
that processes dependent on natural gas as a substantial feed are
also more economically favorable. One process that can directly
benefit from a reduced natural gas cost is steam reforming of
methane to form hydrogen and/or syngas.
[0004] One of the challenges in processing of liquid petroleum
feeds is that the hydrogen to carbon ratio of the petroleum feed is
often lower than the hydrogen to carbon ratio of the desired
products from a feed. Some refinery processes can generate small
volumes of excess hydrogen, but in general hydrogen is a limited
resource.
[0005] U.S. Pat. Nos. 8,722,563 and 8,722,564 describe
multimetallic hydroprocessing catalysts prepared by forming a
catalyst precursor and then heating the catalyst precursor to form
the catalyst. The multimetallic catalysts are described as having
improved activity for hydrodenitrogenation of various types of
feeds.
[0006] U.S. Pat. No. 6,582,590 and U.S. Pat. No. 6,929,738 describe
various types of processing sequences that include hydroprocessing
in the presence of a bulk multimetallic catalyst. The processes are
described as being suitable for production of various product
fractions, including distillate fuels.
SUMMARY
[0007] In an aspect, a hydrotreatment process is provided
comprising: reacting a feedstream, the feedstream having a sulfur
content of about 500 wppm to about 50000 wppm and an aromatics
content of at least about 60 wt %, or at least about 70 wt %, in
the presence of a hydrogen-containing treat gas and in the presence
of a mixed metal catalyst under effective hydrotreating conditions
for converting about 5 wt % or less of the feedstream relative to a
conversion temperature of 350.degree. F. (177.degree. C.); and
separating the first liquid effluent to produce a vapor phase
stream and a liquid product stream, the liquid product stream
having a sulfur content of about 500 wppm or less, wherein the
mixed metal catalyst comprises a sulfided mixed metal catalyst
formed by sulfiding a mixed metal catalyst precursor composition,
the mixed metal catalyst precursor composition being produced by a)
heating a composition comprising at least one metal from Group 6 of
the Periodic Table of the Elements, at least one metal from Groups
8-10 of the Periodic Table of the Elements, and a reaction product
formed from (i) a first organic compound containing at least one
amine group, and (ii) a second organic compound separate from said
first organic compound and containing at least one carboxylic acid
group to a temperature from about 195.degree. C. to about
260.degree. C. for a time sufficient for the first and second
organic compounds to form a reaction product in situ that contains
an amide moiety, unsaturated carbon atoms not present in the first
or second organic compounds, oxygen atoms not present in the first
or second organic compounds, or a combination thereof; b) heating a
composition comprising one metal from Group 6 of the Periodic Table
of the Elements, at least one metal from Groups 8-10 of the
Periodic Table of the Elements, and a reaction product formed from
(iii) a first organic compound containing at least one amine group
and at least 10 carbon atoms or (iv) a second organic compound
containing at least one carboxylic acid group and at least 10
carbon atoms, but not both (iii) and (iv), wherein the reaction
product contains additional unsaturated carbon atoms, relative to
(iii) the first organic compound or (iv) the second organic
compound, wherein the metals of the catalyst precursor composition
are arranged in a crystal lattice, and wherein the reaction product
is not located within the crystal lattice, to a temperature from
about 195.degree. C. to about 260.degree. C. for a time sufficient
for the first or second organic compounds to form a reaction
product in situ that contains unsaturated carbon atoms not present
in the first or second organic compounds, oxygen atoms not present
in the first or second organic compounds, or a combination thereof;
or c) heating a composition comprising at least one metal from
Group 6 of the Periodic Table of the Elements, at least one metal
from Groups 8-10 of the Periodic Table of the Elements, and a
pre-formed amide formed from (v) a first organic compound
containing at least one amine group, and (vi) a second organic
compound separate from said first organic compound and containing
at least one carboxylic acid group, to form at least one of
additional in situ unsaturated carbon atoms or in situ added oxygen
atoms not present in the first organic compound, the second organic
compound, or both, but not for so long that the pre-formed amide
substantially decomposes, thereby forming a catalyst precursor
containing at least one of in situ formed unsaturated carbon atoms
or in situ added oxygen atoms.
[0008] Optionally, reacting the feedstream in the presence of a
mixed metal catalyst further comprises reacting the feedstream in
the presence of one or more additional hydrotreating catalysts.
Further optionally, the one or more additional hydrotreating
catalysts and the mixed metal catalyst can comprise a catalyst
mixture, or the one or more additional hydrotreating catalysts and
the mixed metal catalyst can comprise a stacked bed of catalysts,
or the one or more additional hydrotreating catalysts and the mixed
metal catalyst can be located in separate catalyst beds, or a
combination thereof.
[0009] In another aspect, a multistage hydroprocessing process is
provided comprising: reacting a feedstream having a sulfur content
of at least about 3000 wppm in a first hydroprocessing stage in the
presence of a hydrogen-containing treat gas and in the presence of
at least one first stage hydroprocessing catalyst, the first
hydroprocessing stage being operated at first stage hydroprocessing
conditions, thereby resulting in a first liquid effluent having a
sulfur content of about 3000 wppm or less; separating at least a
portion of the first liquid effluent to produce a first vapor phase
stream and a first liquid product stream; reacting at least a
portion of the first liquid product stream in a second
hydroprocessing stage in the presence of a hydrogen-containing
treat gas and a mixed metal catalyst, the second hydroprocessing
stage being operated at second stage hydroprocessing conditions to
produce a second liquid effluent; and separating at least a portion
of the second liquid effluent to produce a second vapor phase
stream and a second liquid product stream having a sulfur content
of about 500 wppm or less, wherein the mixed metal catalyst
comprises a sulfided mixed metal catalyst formed by sulfiding a
mixed metal catalyst precursor composition, the mixed metal
catalyst precursor composition being produced by a) heating a
composition comprising at least one metal from Group 6 of the
Periodic Table of the Elements, at least one metal from Groups 8-10
of the Periodic Table of the Elements, and a reaction product
formed from (i) a first organic compound containing at least one
amine group, and (ii) a second organic compound separate from said
first organic compound and containing at least one carboxylic acid
group to a temperature from about 195.degree. C. to about
260.degree. C. for a time sufficient for the first and second
organic compounds to form a reaction product in situ that contains
an amide moiety, unsaturated carbon atoms not present in the first
or second organic compounds, oxygen atoms not present in the first
or second organic compounds, or a combination thereof; b) heating a
composition comprising one metal from Group 6 of the Periodic Table
of the Elements, at least one metal from Groups 8-10 of the
Periodic Table of the Elements, and a reaction product formed from
(iii) a first organic compound containing at least one amine group
and at least 10 carbon atoms or (iv) a second organic compound
containing at least one carboxylic acid group and at least 10
carbon atoms, but not both (iii) and (iv), wherein the reaction
product contains additional unsaturated carbon atoms, relative to
(iii) the first organic compound or (iv) the second organic
compound, wherein the metals of the catalyst precursor composition
are arranged in a crystal lattice, and wherein the reaction product
is not located within the crystal lattice, to a temperature from
about 195.degree. C. to about 260.degree. C. for a time sufficient
for the first or second organic compounds to form a reaction
product in situ that contains unsaturated carbon atoms not present
in the first or second organic compounds, oxygen atoms not present
in the first or second organic compounds, or a combination thereof;
or c) heating a composition comprising at least one metal from
Group 6 of the Periodic Table of the Elements, at least one metal
from Groups 8-10 of the Periodic Table of the Elements, and a
pre-formed amide formed from (v) a first organic compound
containing at least one amine group, and (vi) a second organic
compound separate from said first organic compound and containing
at least one carboxylic acid group, to form at least one of
additional in situ unsaturated carbon atoms or in situ added oxygen
atoms not present in the first organic compound, the second organic
compound, or both, but not for so long that the pre-formed amide
substantially decomposes, thereby forming a catalyst precursor
containing at least one of in situ formed unsaturated carbon atoms
or in situ added oxygen atoms. Optionally, the first liquid
effluent can have a sulfur content of at least about 1000 wppm, or
at least about 1500 wppm, or at least about 2000 wppm.
[0010] In still another aspect, a multistage hydroprocessing
process is provided comprising: reacting a feedstream in a first
hydroprocessing stage in the presence of a hydrogen-containing
treat gas, the first stage containing one or more reaction zones,
each reaction zone operated at first stage hydroprocessing
conditions and in the presence of a first hydroprocessing catalyst,
thereby resulting in a first liquid effluent; separating at least a
portion of the first liquid effluent to produce a first vapor phase
stream and a first liquid product stream, the first liquid product
stream having a sulfur content of about 1000 wppm to about 5000
wppm; reacting at least a portion of the first liquid product
stream in a second hydroprocessing stage in the presence of a
hydrogen-containing treat gas, the second hydroprocessing stage
containing at least one reaction zone operated at second stage
hydroprocessing conditions, the at least one reaction zone
containing a mixed metal hydroprocessing catalyst, thereby
resulting in a second liquid effluent; and separating at least a
portion of the second liquid effluent to produce a second vapor
phase stream and a second liquid product stream, the second liquid
product stream having a sulfur content of about 100 wppm or less;
wherein the mixed metal catalyst comprises a sulfided mixed metal
catalyst formed by sulfiding a mixed metal catalyst precursor
composition, the mixed metal catalyst precursor composition being
produced by a) heating a composition comprising at least one metal
from Group 6 of the Periodic Table of the Elements, at least one
metal from Groups 8-10 of the Periodic Table of the Elements, and a
reaction product formed from (i) a first organic compound
containing at least one amine group, and (ii) a second organic
compound separate from said first organic compound and containing
at least one carboxylic acid group to a temperature from about
195.degree. C. to about 260.degree. C. for a time sufficient for
the first and second organic compounds to form a reaction product
in situ that contains an amide moiety, unsaturated carbon atoms not
present in the first or second organic compounds, oxygen atoms not
present in the first or second organic compounds, or a combination
thereof; b) heating a composition comprising one metal from Group 6
of the Periodic Table of the Elements, at least one metal from
Groups 8-10 of the Periodic Table of the Elements, and a reaction
product formed from (iii) a first organic compound containing at
least one amine group and at least 10 carbon atoms or (iv) a second
organic compound containing at least one carboxylic acid group and
at least 10 carbon atoms, but not both (iii) and (iv), wherein the
reaction product contains additional unsaturated carbon atoms,
relative to (iii) the first organic compound or (iv) the second
organic compound, wherein the metals of the catalyst precursor
composition are arranged in a crystal lattice, and wherein the
reaction product is not located within the crystal lattice, to a
temperature from about 195.degree. C. to about 260.degree. C. for a
time sufficient for the first or second organic compounds to form a
reaction product in situ that contains unsaturated carbon atoms not
present in the first or second organic compounds, oxygen atoms not
present in the first or second organic compounds, or a combination
thereof; or c) heating a composition comprising at least one metal
from Group 6 of the Periodic Table of the Elements, at least one
metal from Groups 8-10 of the Periodic Table of the Elements, and a
pre-formed amide formed from (v) a first organic compound
containing at least one amine group, and (vi) a second organic
compound separate from said first organic compound and containing
at least one carboxylic acid group, to form at least one of
additional in situ unsaturated carbon atoms or in situ added oxygen
atoms not present in the first organic compound, the second organic
compound, or both, but not for so long that the pre-formed amide
substantially decomposes, thereby forming a catalyst precursor
containing at least one of in situ formed unsaturated carbon atoms
or in situ added oxygen atoms.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 schematically shows an example of a configuration
suitable for processing a feed to produce distillate boiling range
products.
[0012] FIG. 2 schematically shows an example of a configuration
suitable for processing a feed to produce distillate boiling range
products.
DETAILED DESCRIPTION
[0013] All numerical values within the detailed description and the
claims herein are modified by "about" or "approximately" the
indicated value, and take into account experimental error and
variations that would be expected by a person having ordinary skill
in the art.
OVERVIEW
[0014] In various aspects, methods are provided for hydrotreating a
feed to generate a product with a reduced or minimized aromatics
content. For example, a distillate boiling range feed having an
elevated content of sulfur and/or nitrogen can be hydrotreated
using at least two hydrotreating stages with intermediate
separation to produce a hydrotreated distillate boiling range
product with a reduced or minimized aromatics content. Additionally
or alternately, a mixed metal catalyst formed from a suitable
precursor can be used during the hydrotreating. A mixed metal
catalyst formed from a suitable precursor can provide an
unexpectedly superior activity for aromatic saturation. A still
further unexpected benefit can be achieved by combining a
multi-stage hydrotreating process with intermediate separation with
hydrotreating in the presence of a mixed metal catalyst formed from
a suitable precursor.
[0015] Some feeds that have an appropriate boiling range for use as
a distillate fuel correspond to feeds with both a substantial
content of heteroatoms, such as sulfur and nitrogen, and a
substantial content of aromatic compounds. The aromatic compounds
can optionally include multi-ring aromatic compounds. Such aromatic
compounds have a high density relative to aliphatic compounds. By
increasing the amount of hydrogenation of aromatics in a distillate
boiling range feed, the overall density of the resulting liquid
product can be reduced at a given level of feed conversion while
also maintaining a (relatively) constant absolute number of carbon
atoms within the feed. Using hydrogenation to decrease the density
of a petroleum feed can be referred to as a "volume swell" for the
feed. This type of volume swell can be economically valuable for
distillate fuel products, due to the fact that many types of
distillate fuel are sold on a volume basis. By increasing the
volume of distillate fuel corresponding to a given number of carbon
atoms, the overall yield of distillate fuel from a feedstock can be
increased. It is noted that the benefit from volume swell can be
dependent on the ability to increase hydrogenation of the feed
without increasing conversion of the distillate boiling range feed
to naphtha boiling range products.
[0016] The amount of aromatic saturation that occurs during
hydrotreatment can be suppressed for feeds that have elevated
contents of sulfur and/or nitrogen. For example, cycle oils and
other cracked distillate feeds can have sulfur contents of at least
about 3000 wppm or greater, such as about 5000 wppm or greater, or
even about 10000 wppm or greater. A conventional hydrotreating
process can be suitable for reducing the sulfur content of such a
feed to a desired level, such as about 500 wppm or less, or about
250 wppm or less, or about 100 wppm or less. However, the H.sub.2S
generated during hydrotreatment can tend to suppress the aromatic
saturation activity of a hydrotreating catalyst. This can result in
an increased level of aromatics in the hydrotreated product.
[0017] As an example, during a typical hydrotreatment process, the
early (upstream) portions of a hydrotreatment process typically
cause removal of sulfur from compounds that have a faster reaction
rate. The removal of this more easily removed sulfur is not
believed to be strongly impacted by the absence or presence of
H.sub.2S in the hydrogen treat gas. Thus, a treat gas containing
H.sub.2S can be suitable for the initial catalyst beds and/or
stages of a distillate hydrotreater when removing sulfur from a
feed having an elevated sulfur content. However, this easily
removed sulfur can still generate H.sub.2S. As a result, in a
conventional distillate hydrotreater that does not have interstage
separation, the downstream stage(s)/catalyst bed(s)/portions of a
catalyst bed are exposed to the feed in the presence of a treat gas
that can contain at least about 1 vol % H.sub.2S, or at least about
2 vol % H.sub.2S, depending on the amount of sulfur initially
present in the feed. Thus, even though a conventional hydrotreater
may start with a contaminant free hydrogen treat gas, after removal
of a portion of the sulfur in the feed, the downstream portions of
the distillate hydrotreating system effectively receive a treat gas
having an H.sub.2S content of at least about 1 vol % or more. This
H.sub.2S content in the downstream portions of a conventional
distillate hydrotreater can suppress the activity of the downstream
portions of the hydrotreating catalyst for both desulfurization and
aromatic saturation activity.
[0018] In addition to difficulties in performing aromatic
saturation in an environment containing substantial amounts of
H.sub.2S, traditionally increasing the amount of hydrogenation that
occurs when forming a distillate fuel product from a distillate
boiling range feed has not been desirable. Because hydrogen is a
limited resource in a refinery setting, the cost of hydrogen
consumed by saturation of aromatic rings in a distillate fuel was
difficult to justify based on the resulting increase in value in
the distillate fuel products. As a result, the amount of aromatic
saturation performed on a distillate feed was usually limited to be
sufficient for meeting regulatory requirements, such as
specifications for the maximum allowable amounts of polyaromatic
compounds.
[0019] In contrast to conventional processes, a catalyst and/or
hydroprocessing conditions have been identified that allow for
increased or improved aromatic saturation during hydrotreatment of
a distillate feed that contains elevated levels of sulfur. Use of a
catalyst and/or process conditions that allow for improved aromatic
saturation can allow for production of increased volumes of
distillate fuels while reducing or minimizing the amount of
"overcracking" or other excess conversion of a feed. In some
aspects, this can allow processing conditions to be selected based
on a desired level of heteroatom removal while also providing the
volume swell benefit that comes from increased aromatic
saturation.
[0020] Volume swelling in a product can be characterized in any
convenient manner, such as by directly measuring the volume,
measuring the specific gravity of a product, or by measuring the
API gravity of a product. Volume swelling due to processing a feed
as described herein can generally lead to an increase in volume of
about 0.25 vol % to about 2.5 vol % (or possibly more). Although an
increase in volume of less than 1 vol % may appear to be small, due
to the size of typical commercial processing units, and based on
the typical continuous (or near-continuous) operation schedule of
such commercial processing units, an increase in volume of a few
tenths of a percent for a distillate product can correspond to a
substantial and significant increase in total product generated
and/or in commercial value generated over time.
[0021] In some aspects, the methods for distillate hydrotreating
can include use of a catalyst formed from a catalyst precursor
composition comprising at least one metal from Group 6 of the
Periodic Table of the Elements, at least one metal from Groups 8-10
of the Periodic Table of the Elements, and a reaction product
formed from (i) a first organic compound containing at least one
amine group and at least 10 carbons or (ii) a second organic
compound containing at least one carboxylic acid group and at least
10 carbons, but not both (i) and (ii).
[0022] In other aspects, the process can use a catalyst formed from
a catalyst precursor composition comprising at least one metal from
Group 6 of the Periodic Table of the Elements, at least one metal
from Groups 8-10 of the Periodic Table of the Elements, and a
reaction product formed from (i) a first organic compound
containing at least one amine group, and (ii) a second organic
compound separate from said first organic compound and containing
at least one carboxylic acid group. More broadly, this aspect of
the present invention relates to use of a catalyst formed from a
catalyst precursor composition comprising at least one metal from
Group 6 of the Periodic Table of the Elements, at least one metal
from Groups 8-10 of the Periodic Table of the Elements, and a
condensation reaction product formed from (i) a first organic
compound containing at least one first functional group, and (ii) a
second organic compound separate from said first organic compound
and containing at least one second functional group, wherein said
first functional group and said second functional group are capable
of undergoing a condensation reaction and/or a (decomposition)
reaction causing an additional unsaturation to form an associated
product.
[0023] In still other aspects, the process can use a catalyst
formed from a catalyst precursor composition comprising at least
one metal from Group 6 of the Periodic Table of the Elements, at
least one metal from Groups 8-10 of the Periodic Table of the
Elements, and a reaction product comprising an amide group. In this
type of aspect, the reaction product is formed prior to
incorporation into the catalyst precursor. The reaction product is
an amide-containing reaction product formed from an ex-situ
reaction of (i) a first organic compound containing at least one
amine group, and (ii) a second organic compound separate from said
first organic compound and containing at least one carboxylic acid
group.
[0024] In yet other aspects, a reaction system including a
plurality of reaction stages with intermediate separation for
removal of gases can be used to produce a hydrotreated distillate
product with reduced aromatic content by processing a distillate
feed in the presence of a conventional hydrotreating catalyst
and/or a mixed metal catalyst. One or more initial stages can be
used to reduce the sulfur from an elevated amount to an amount less
than about 5000 wppm, such as less than about 3000 wppm. Gases can
be separated from the effluent of the initial stages to reduce or
minimize the H.sub.2S and/or NH.sub.3 content prior to one or more
additional hydrotreating stages. Reducing or minimizing the
H.sub.2S content can allow for increased aromatic saturation
activity in the additional hydrotreating stages.
Feedstock
[0025] In various aspects, methods are provided for improving the
yield of distillate products from hydrotreatment of distillate
feedstocks and/or heavier feedstocks that have elevated sulfur
content. Examples of suitable feedstocks can include, but are not
limited to, atmospheric gas oils, vacuum gas oil feeds, cycle oils,
and/or other feeds (such as cracked feeds) having a similar type of
boiling range, during the production of distillate fuels. In
addition to using a mixed metal catalyst formed from a suitable
precursor, the methods can involve stripping of gases to separate
out contaminant gases (such as H.sub.2S and/or NH.sub.3) during
hydrotreatment of a feed. This can allow for an improved yield of
distillate products at a desired level of heteroatom removal. The
improved yield of distillate can be achieved while reducing or
minimizing production of lower boiling compounds, such as light
ends or naphtha boiling range products. In some aspects, the
improved yield can be based in part on increased volume swell of
the distillate products due to having a reduced or minimized amount
of aromatics in the resulting distillate products. Particular
examples of suitable feeds can include raw virgin distillate feeds,
such as straight run light vacuum gas oils, and catalytically
cracked feeds, such as distillate boiling range cycle oils produced
during fluid catalytic cracking or coker distillate feeds.
[0026] More generally, a wide range of petroleum and chemical
feedstocks can be hydroprocessed in accordance with the present
invention. Suitable feedstocks include whole and reduced petroleum
crudes, atmospheric and vacuum residua, propane deasphalted
residua, e.g., brightstock, cycle oils, FCC tower bottoms, gas
oils, including atmospheric and vacuum gas oils and coker gas oils,
light to heavy distillates including raw virgin distillates,
hydrocrackates, hydrotreated oils, dewaxed oils, slack waxes.
Fischer-Tropsch waxes, raffinates, and mixtures thereof.
[0027] In this discussion, the distillate boiling range is defined
as 350.degree. F. (177.degree. C.) to 700.degree. F. (371.degree.
C.). Distillate boiling range products can include products
suitable for use as kerosene products (including jet fuel products)
and diesel products, such as premium diesel or winter diesel
products. Such distillate boiling range products can be suitable
for use directly, or optionally after further processing. With
regard to other boiling ranges, the lubricant boiling range is
defined as 700.degree. F. (371.degree. C.) to 950.degree. F.
(482.degree. C.) and the naphtha boiling range is defined as
100.degree. F. (37.degree. C.) to 350.degree. F. (177.degree.
C.).
[0028] One way of defining a feedstock is based on the boiling
range of the feed. One option for defining a boiling range is to
use an initial boiling point for a feed and/or a final boiling
point for a feed. Another option, which in some instances may
provide a more representative description of a feed, is to
characterize a feed based on the amount of the feed that boils at
one or more temperatures. The amount of a feed that boils at a
given temperature can be referred to as a fractional weight boiling
point. For example, a "T5" boiling point for a feed is defined as
the temperature at which 5 wt % of the feed will boil off.
Similarly, a "T95" boiling point is a temperature at which 95 wt %
of the feed will boil, while a "T99.5" boiling point is a
temperature at which 99.5 wt % of the feed will boil.
[0029] In some aspects, a distillate boiling range feedstock can
correspond to a feed where at least a substantial portion of the
feed has a boiling point in the distillate boiling range. In
various aspects, a distillate boiling range feedstock can have a
T20 boiling point, or a T10 boiling point, or a T5 boiling point of
at least about 350.degree. F. (177.degree. C.), or at least about
400.degree. F. (204.degree. C.), or at least about 450.degree. F.
(232.degree. C.). Additionally or alternately, a distillate boiling
range feedstock can have a T95 boiling point, or a T90 boiling
point, or a T75 boiling point of about 900.degree. F. (482.degree.
C.) or less, or about 850.degree. F. (454.degree. C.) or less, or
about 800.degree. F. (427.degree. C.) or less, or about 750.degree.
F. (399.degree. C.) or less, or about 700.degree. F. (371.degree.
C.) or less. In still further additional or alternate aspects, a
distillate boiling range feedstock can have two or more of the
above fractional weight boiling points, or three or more of the
above fractional weight boiling points, or any other convenient
combination. Examples of distillate boiling range feedstocks having
two or more of the above fractional weight boiling points include
feeds with a T5 boiling point of at least about 350.degree. F.
(177.degree. C.) and a T20 boiling point of at least about
450.degree. F. (232.degree. C.), or a T5 boiling point of at least
about 400.degree. F. (204.degree. C.) and a T95 boiling point of
850.degree. F. (454.degree. C.) or less, or another convenient
combination. It is noted that all combinations of explicitly
recited fractional weight boiling points are also explicitly
contemplated in conjunction with each other to provide distillate
boiling range feedstocks having two or more of the above fractional
weight boiling points, or three or more of the above fractional
weight boiling points.
[0030] In various aspects, a distillate boiling range feedstock
containing high levels of sulfur and/or nitrogen can be passed into
one or more hydrodesulfurization reaction stages to remove sulfur
and nitrogen. Suitable distillate boiling range feedstocks can be
feeds containing at least about 3000 wppm sulfur, or at least about
4000 wppm sulfur, or at least about 5000 wppm sulfur, or at least
about 7500 wppm sulfur, or at least about 10,000 wppm sulfur, or at
least about 15,000 wppm sulfur, or at least about 20,000 wppm
sulfur, such as up to about 50,000 wppm sulfur.
[0031] In some alternative aspects, a feed with a higher boiling
range can be used, such as a feed with an initial boiling point of
at least about 650.degree. F. (343.degree. C.), or at least about
700.degree. F. (371.degree. C.), or at least about 750.degree. F.
(399.degree. C.). Alternatively, a feed may be characterized using
a T5 boiling point, such as a feed with a T5 boiling point of at
least about 650.degree. F. (343.degree. C.), or at least about
700.degree. F. (371.degree. C.), or at least about 750.degree. F.
(399.degree. C.). Such a feed can have a final boiling point of
about 1150.degree. F. (621.degree. C.), or about 1100.degree. F.
(593.degree. C.) or less, or about 1050.degree. F. (566.degree. C.)
or less. Alternatively, such a feed may be characterized using a
T95 boiling point, such as a feed with a T95 boiling point of about
1150.degree. F. (621.degree. C.), or about 1100.degree. F.
(593.degree. C.) or less, or about 1050.degree. F. (566.degree. C.)
or less.
[0032] In some aspects, the aromatics content of the feed prior to
hydroprocessing can be at least about 30 wt % aromatics, or at
least about 40 wt %, or at least about 50 wt %, or at least about
60 wt %, or at least about 70 wt %, such as up to about 80 wt % or
more or up to about 90 wt % or more. After hydroprocessing, the
aromatics content of the distillate boiling range liquid product
from the final hydrotreating stage can be about 60 wt % or less, or
about 50 wt % or less, or about 40 wt % or less, or about 30 wt %
or less. Each of the above upper bounds for the aromatics content
is explicitly contemplated herein in combination with each of the
above lower bounds for the aromatics content.
[0033] In some aspects, the content of multi-ring aromatics in the
feed prior to hydroprocessing can be at least about 20 wt %
multi-ring aromatics, or at least about 25 wt %, or at least about
30 wt %, or at least about 35 wt %, or at least about 40 wt %, or
at least about 45 wt %, or at least about 50 wt %, such as up to
about 60 wt % or more. After hydroprocessing, the multi-ring
aromatics content of the distillate boiling range liquid product
from the final hydrotreating stage can be about 10 wt % or less, or
about 7.5 wt % or less, or about 5 wt % or less, or about 3 wt % or
less. Each of the above upper bounds for the multi-ring aromatics
content is explicitly contemplated herein in combination with each
of the above lower bounds for the multi-ring aromatics content.
[0034] In some aspects, at least a portion of the feed can
correspond to a feed derived from a biocomponent source. In this
discussion, a biocomponent feedstock refers to a hydrocarbon
feedstock derived from a biological raw material component, from
biocomponent sources such as vegetable, animal, fish, and/or algae.
Note that, for the purposes of this document, vegetable fats/oils
refer generally to any plant based material, and can include
fats/oils derived from a source such as plants of the genus
Jatropha. Generally, the biocomponent sources can include vegetable
fats/oils, animal fats/oils, fish oils, pyrolysis oils, and algae
lipids/oils, as well as components of such materials, and in some
embodiments can specifically include one or more type of lipid
compounds. Lipid compounds are typically biological compounds that
are insoluble in water, but soluble in nonpolar (or fat) solvents.
Non-limiting examples of such solvents include alcohols, ethers,
chloroform, alkyl acetates, benzene, and combinations thereof.
Process Configuration
[0035] In various aspects, methods are provided for improving the
yield of distillate products from hydrotreatment of distillate
feedstocks and/or heavier feedstocks that have elevated sulfur
content. Examples of suitable feedstocks can include, but are not
limited to, atmospheric gas oils, vacuum gas oil feeds, cycle oils,
and/or other feeds (such as cracked feeds) having a similar type of
boiling range, during the production of distillate fuels. In
addition to using a mixed metal catalyst formed from a suitable
precursor, the methods can involve stripping of gases to separate
out contaminant gases (such as H.sub.2S and/or NH.sub.3) during
hydrotreatment of a feed. This can allow for an improved yield of
distillate products at a desired level of heteroatom removal. The
improved yield of distillate can be achieved while reducing or
minimizing production of lower boiling compounds, such as light
ends or naphtha boiling range products. In some aspects, the
improved yield can be based in part on increased volume swell of
the distillate products due to having a reduced or minimized amount
of aromatics in the resulting distillate products.
[0036] In some aspects, a feed can be hydrodesulfurized in a first
stage, which contains one or more reaction zones, in the presence
of hydrogen and a first hydrotreating catalyst under
hydrodesulfurizing conditions. The product stream can then be
passed to a separation zone wherein a vapor phase stream and a
liquid phase (product) stream are produced. The liquid phase
product stream is a passed to a second hydrodesulfurization stage,
which contains at least one reaction zone, where it is further
hydrodesulfurized in the presence of hydrogen and a second
hydrodesulfurization catalyst. The liquid product stream from the
second hydrodesulfurization stage is passed to a second separation
zone wherein a vapor product stream is collected for further
processing or blending. Optionally, the liquid product stream from
the second hydrodesulfurization zone can be passed to a third
reaction stage which is operated in the presence of a dewaxing
catalyst, a hydrogenation catalyst, or another hydrotreating
catalyst. Optionally, the liquid product stream from the first
hydrodesulfurization zone can be passed to an additional
intermediate hydrodesulfurization stage between the first and
second stage. It is within the scope of this invention that at
least a portion of the vapor product stream from either or both of
the first and second reaction stages can be recycled to the first
reaction stage. Optionally but preferably, the vapor product stream
from the first reaction stage and/or the second reaction stage is
not recycled to the second reaction stage. The vapor product stream
from a hydrotreating reaction stage can typically contain H.sub.2S
and/or NH.sub.3. Recycling such a stream to the second reaction
stage could reduce or minimize the desired additional aromatic
saturation that can provide volume swell of the hydrotreated
distillate product.
[0037] A variety of process schemes can be used for hydroprocessing
a feed as described above. In some aspects, a reaction system can
include at least two hydrotreatment stages. Each hydrotreatment
stage can include a hydrotreating catalyst, such as a conventional
hydrotreating catalyst, a mixed metal catalyst formed from a
suitable precursor, or a combination thereof. A gas-liquid
separation can be performed between the hydrotreatment stages to
reduce or minimize the content of contaminant gases in the second
hydrotreatment stage.
[0038] As another example, at least three separate reaction stages
can be used, each containing one or more reaction zones, with each
zone containing at least one bed of catalyst. The first two
reaction stages can contain hydrodesulfurization catalysts and the
third reaction stage (and any further downstream stages) can
contain a hydrogenation catalyst, a dewaxing catalyst, a
hydrocracking catalyst, and/or a hydrotreating catalyst. Each
reaction stage can optionally further include a mixed metal
catalyst. Depending on the aspect, the mixed metal catalyst can
serve as the hydrodesulfurization catalyst in a stage, or the mixed
metal catalyst can be present in addition to a hydrodesulfurization
catalyst (or hydrogenation catalyst or dewaxing catalyst or
hydrocracking catalyst). In some aspects, when this process scheme
is practiced the feedstock introduced into the first reaction stage
can be a distillate boiling range feedstock. One suitable type of
feedstock can be a distillate boiling range feedstock from an
atmospheric distillation tower, such as a raw virgin petroleum
distillate. Another example of a suitable feedstock can be a
cracked feedstock, such as a light cycle oil from a fluid catalytic
cracking process. Such feedstocks can contain (for example) at
least about 3000 wppm sulfur, or at least about 4000 wppm sulfur,
or at least about 5000 wppm sulfur, or at least about 10,000 wppm
sulfur, or at least about 15,000 wppm sulfur, and optionally can
further contain a relatively high nitrogen content. In other
aspects, such as some aspects where the third reaction stage
(and/or a later reaction stage) includes a dewaxing catalyst and/or
a hydrocracking catalyst, a feed having a boiling range suitable
for production of lubricant base oils can be used in addition to or
in place of a distillate boiling range feed.
[0039] After being hydrodesulfurized in a first
hydrodesulfurization stage the feed product stream can contain from
about 500 to about 20000 wppm sulfur, or about 500 to about 5000
wppm, or about 500 to about 3000 wppm, or about 750 to about 20000
wppm, or about 750 to about 5000 wppm, or about 750 to about 3000
wppm, or about 1000 to about 20000 wppm, or about 1000 to about
5000 wppm, or about 1000 to about 3000 wppm, or about 1500 to about
20000 wppm, or about 1500 to about 5000 wppm, or about 1500 to
about 3000 wppm. This amount of sulfur removal can correspond to
removal of about 40% to about 80% of the sulfur initially present
in the feedstock, and optionally can correspond to removal of about
40% to about 70% of the sulfur, or about 40% to about 60%. It is
preferred that at least one of the reaction zones can contain a bed
of the mixed metal catalyst. For example, the reactor of the first
and/or second hydrodesulfurization stage can contain a stacked bed
arrangement wherein a conventional hydrodesulfurization catalyst
comprises one or more reaction zones and a mixed metal catalyst
comprises the other one or more reaction zones. It is preferred
that if a conventional hydrodesulfurization catalyst and a mixed
metal catalyst are used, the conventional catalyst can be in the
upstream reaction zone or zones. It is preferred that the mixed
metal catalyst is present in at least the second
hydrodesulfurization stage. In some aspects, the plurality of
reaction stages can correspond to two reaction stages, with the
second reaction stage preferably containing the mixed metal
catalyst.
[0040] The reaction product is passed to a separation zone where a
vapor phase product stream and a liquid phase product stream is
produced. The liquid phase product stream (having a reduced sulfur
content) can then be introduced into the second
hydrodesulfurization stage, which also contains one or more
reaction zones. This second hydrodesulfurization stage, like the
first, can contain, in one or more of its reaction zones the mixed
metal catalyst. If present, the other catalyst can be a
conventional hydrodesulfurization catalyst. The product stream is
passed to a second separation zone wherein a vapor phase and liquid
phase product streams are produced. The resulting liquid phase
product stream can then contain less than about 150 wppm sulfur, or
less than about 100 wppm, or less than about 50 wppm sulfur, or
less than about 25 wppm sulfur, or less than about 10 wppm sulfur.
This twice hydrodesulfurized product stream can optionally be
passed to a third reaction stage. In some aspects, the twice
hydrodesulfurized liquid product stream can be reacted in the
presence of hydrogen and a catalyst capable of further reducing the
sulfur and nitrogen levels and hydrogenating aromatics. In such
aspects, the sulfur level of the final product stream can be less
than about 10 wppm, preferably less than about 5 wppm, and more
preferably less than about 1 wppm sulfur. In such aspects, the
third reaction stage can contain, in at least one reaction zone, a
hydrogenation catalyst and optionally the mixed metal catalyst. In
other aspects, the third reaction stage can include a dewaxing
catalyst.
[0041] FIGS. 1 and 2 provide a comparison between a conventional
hydrotreating configuration and a hydrotreating configuration
suitable for increasing the amount of volume swell during
processing of a distillate boiling range feed to form a distillate
boiling range product. As noted above, examples of suitable
feedstocks can include (but are not limited to) distillate boiling
range feedstocks, gas oil (atmospheric and/or vacuum) boiling range
feedstocks, or another type of feedstock having a T10 boiling point
of at least about 350.degree. F. (177.degree. C.) and at least
about 3000 wppm of sulfur prior to hydrotreatment.
[0042] In the conventional configuration shown in FIG. 1, a feed
105 is hydrotreated in multiple stages for removal of sulfur and/or
nitrogen. For example, the feed 105 can be hydrotreated in two
stages (and/or reactors) using hydrotreatment stage (and/or
reactor) 110 and hydrotreatment stage (and/or reactor) 120. The
effluent 115 from hydrotreatment stage 110 is cascaded into second
hydrotreatment stage 120 without stripping or other intermediate
separation. The second hydrotreatment stage generates a
hydrotreated effluent 122 that can include a distillate boiling
range product with reduced heteroatom content.
[0043] FIG. 2 shows configuration where the effluent 115 can pass
through a separation stage 225 after hydrotreatment stage 110 and
prior to second hydrotreatment stage 120. One option is to use a
gas-liquid separator or stripper as separation stage 225. In this
option, contaminant gases 228 formed during hydrotreatment in first
hydrotreatment stage 110, such as H.sub.2S and NH.sub.3, as well as
other light ends, can be removed from the effluent prior to second
hydrotreatment stage 120.
[0044] The types of configurations exemplified by FIG. 2 can
provide at least two types of benefits relative to a configuration
similar to FIG. 1. For configurations where contaminant gases are
removed prior to passing the hydrotreated effluent into the second
hydrotreatment stage, the removal of contaminant gases allows for
use of milder reaction conditions in the second hydrotreatment
stage while achieving a similar level of contaminant removal and/or
feed conversion. This can be due, for example, to the catalysts in
the second hydrotreatment stage having a higher effective catalytic
activity for desulfurization when catalyst suppressants or poisons
(such as contaminant gases) are removed. Additionally, for a given
level of reaction condition severity for desulfurization, the
amount of aromatic saturation performed can be increased due to
removal of contaminants that suppress aromatic saturation
activity.
[0045] In various alternative aspects, a mixed metal catalyst
formed from a suitable precursor can be used in one or more
reactors of a convenient reaction system, such as the reaction
system schematically represented in FIG. 1. A mixed metal catalyst
formed from a suitable precursor can be suitable for
hydroprocessing under sour conditions, such as for hydrotreating in
reactor 110, hydrotreating in reactor 120, or in a combination
thereof.
[0046] In this discussion, the severity of hydroprocessing
performed on a feed can be characterized based on an amount of
conversion of the feedstock. In various aspects, the reaction
conditions in the reaction system can be selected to generate a
desired level of conversion of a feed. Conversion of a feed is
defined in terms of conversion of molecules that boil above a
temperature threshold to molecules below that threshold. The
conversion temperature can be any convenient temperature. Unless
otherwise specified, the conversion temperature in this discussion
is a conversion temperature of 350.degree. F. (177.degree. C.).
[0047] The amount of conversion can correspond to the total
conversion of molecules within any stage of the reaction system
that is used to hydroprocess the lower boiling portion of the feed
from the vacuum distillation unit. The amount of conversion desired
for a suitable feedstock can depend on a variety of factors, such
as the boiling range of the feedstock, the amount of heteroatom
contaminants (such as sulfur and/or nitrogen) in the feedstock,
and/or the nature of the desired lubricant products. Suitable
amounts of conversion across all hydroprocessing stages can
correspond to about 15 wt % or less conversion of 350.degree.
F.+(177.degree. C.+) portions of the feedstock to portions boiling
below 350.degree. F., such as about 10 wt % or less, or about 5 wt
% or less, or about 3 wt % or less. It is noted that a conversion
temperature of 350.degree. F. (177.degree. C.) is an indicator of
preserving the distillate boiling range nature of compounds in a
feed. Portions of a feed that are converted relative to a
conversion temperature of 350.degree. F. (177.degree. C.) can tend
to correspond to compounds that are more suitable for inclusion in
a naphtha product as opposed to a distillate product. It is also
noted that sulfur and/or nitrogen in a distillate boiling range
feed can tend to be present primarily in heavier and/or higher
boiling compounds within a feed. During hydrodesulfurization, these
sulfur and/or nitrogen containing compounds may be altered when
sulfur and/or nitrogen is removed, and this alteration may lower
the boiling point. However, if the boiling point of the
desulfurized (or denitrogenated) product compound is still greater
than the conversion temperature, this is not considered
"conversion" of the feed relative to the conversion
temperature.
[0048] In this discussion, a stage can correspond to a single
reactor or a plurality of reactors. Optionally, multiple parallel
reactors can be used to perform one or more of the processes, or
multiple parallel reactors can be used for all processes in a
stage. Each stage and/or reactor can include one or more catalyst
beds containing hydroprocessing catalyst. Note that a "bed" of
catalyst in the discussion below can refer to a partial physical
catalyst bed. For example, a catalyst bed within a reactor could be
filled partially with a hydrocracking catalyst and partially with a
dewaxing catalyst. For convenience in description, even though the
two catalysts may be stacked together in a single catalyst bed, the
hydrocracking catalyst and dewaxing catalyst can each be referred
to conceptually as separate catalyst beds.
Process Conditions--Hydrotreatment
[0049] In various aspects, hydrotreating of a feed can be performed
by exposing the feed to a hydrotreating catalyst and/or a mixed
metal catalyst formed from a suitable precursor in the presence of
hydrogen. A hydrogen stream is, therefore, fed or injected into a
vessel or reaction zone or hydroprocessing zone in which the
hydroprocessing catalyst is located. Hydrogen, which is contained
in a hydrogen-containing "treat gas," is provided to the reaction
zone. Treat gas, as referred to in this invention, can be either
pure hydrogen or a hydrogen-containing gas, which is a gas stream
containing hydrogen in an amount that is sufficient for the
intended reaction(s), optionally including one or more other gases
(e.g., nitrogen and light hydrocarbons such as methane), and which
will not adversely interfere with or affect either the reactions or
the products. Impurities, such as H.sub.2S and NH.sub.3 are
undesirable and would typically be removed from the treat gas
before it is conducted to the reactor. The treat gas stream
introduced into a reaction stage will preferably contain at least
about 50 vol. % and more preferably at least about 75 vol. %
hydrogen.
[0050] Hydrotreating conditions can include temperatures of about
200.degree. C. to about 450.degree. C., or about 315.degree. C. to
about 425.degree. C.; pressures of about 250 psig (1.8 MPag) to
about 5000 psig (34.6 MPag) or about 300 psig (2.1 MPag) to about
3000 psig (20.8 MPag); liquid hourly space velocities (LHSV) of
about 0.1 hr.sup.-1 to about 10 hr.sup.-; and hydrogen treat rates
of about 200 scf/B (35.6 m.sup.3/m.sup.3) to about 10,000 scf/B
(1781 m.sup.3/m.sup.3), or about 500 (89 m.sup.3/m.sup.3) to about
10,000 scf, (1781 m.sup.3/m.sup.3).
[0051] The catalysts used for hydrotreatment can include
conventional hydroprocessing catalysts, such as those that comprise
at least one Group VIII non-noble metal (Columns 8-10 of IUPAC
periodic table), preferably Fe, Co, and/or Ni, such as Co and/or
Ni; and at least one Group VIB metal (Column 6 of IUPAC periodic
table), preferably Mo and/or W. Such hydroprocessing catalysts can
optionally include transition metal sulfides. These metals or
mixtures of metals are typically present as oxides or sulfides on
refractory metal oxide supports. Suitable metal oxide supports
include low acidic oxides such as silica, alumina, titania,
silica-titania, and titania-alumina. Suitable aluminas are porous
aluminas such as gamma or eta having average pore sizes from 50 to
200 .ANG., or 75 to 150 .ANG.; a surface area from 100 to 300
m.sup.2/g, or 150 to 250 m.sup.2/g; and a pore volume of from 0.25
to 1.0 cm.sup.3/g, or 0.35 to 0.8 cm.sup.3/g. The supports are
preferably not promoted with a halogen such as fluorine as this
generally increases the acidity of the support.
[0052] The at least one Group VIII non-noble metal, in oxide form,
can typically be present in an amount ranging from about 1 wt % to
about 40 wt %, preferably from about 4 wt % to about 15 wt %. The
at least one Group VIB metal, in oxide form, can typically be
present in an amount ranging from about 2 wt % to about 70 wt %,
preferably for supported catalysts from about 6 wt % to about 40 wt
% or from about 10 wt % to about 30 wt %. These weight percents are
based on the total weight of the catalyst. Suitable metal catalysts
include cobalt/molybdenum (1-10% Co as oxide, 10-40% Mo as oxide),
nickel/molybdenum (1-10% Ni as oxide, 10-40% Co as oxide), or
nickel/tungsten (1-10% Ni as oxide, 10-40% W as oxide) on alumina,
silica, silica-alumina, or titania.
[0053] Alternatively, the hydrotreating catalyst can be a bulk
metal catalyst, or a combination of stacked beds of supported and
bulk metal catalyst. By bulk metal, it is meant that the catalysts
are unsupported wherein the bulk catalyst particles comprise 30-100
wt. % of at least one Group VIII non-noble metal and at least one
Group VIB metal, based on the total weight of the bulk catalyst
particles, calculated as metal oxides and wherein the bulk catalyst
particles have a surface area of at least 10 m.sup.2/g. It is
furthermore preferred that the bulk metal hydrotreating catalysts
used herein comprise about 50 to about 100 wt %, and even more
preferably about 70 to about 100 wt %, of at least one Group VIII
non-noble metal and at least one Group VIB metal, based on the
total weight of the particles, calculated as metal oxides. The
amount of Group VIB and Group VIII non-noble metals can easily be
determined VIB TEM-EDX.
[0054] Bulk catalyst compositions comprising one Group VIII
non-noble metal and two Group VIB metals are preferred. It has been
found that in this case, the bulk catalyst particles are
sintering-resistant. Thus the active surface area of the bulk
catalyst particles is maintained during use. The molar ratio of
Group VIB to Group VIII non-noble metals ranges generally from
10:1-1:10 and preferably from 3:1-1:3. In the case of a core-shell
structured particle, these ratios of course apply to the metals
contained in the shell. If more than one Group VIB metal is
contained in the bulk catalyst particles, the ratio of the
different Group VIB metals is generally not critical. The same
holds when more than one Group VIII non-noble metal is applied. In
the case where molybdenum and tungsten are present as Group VIB
metals, the molybdenum:tungsten ratio preferably lies in the range
of 9:1-1:9. Preferably the Group VIII non-noble metal comprises
nickel and/or cobalt. It is further preferred that the Group VIB
metal comprises a combination of molybdenum and tungsten.
Preferably, combinations of nickelmolybdenum/tungsten and
cobalt/molybdenum/tungsten and nickel/cobalt/molybdenum/tungsten
are used. These types of precipitates appear to be
sinter-resistant. Thus, the active surface area of the precipitate
is maintained during use. The metals are preferably present as
oxidic compounds of the corresponding metals, or if the catalyst
composition has been sulfided, sulfidic compounds of the
corresponding metals.
[0055] It is also preferred that the bulk metal hydrotreating
catalysts used herein have a surface area of at least 50 m.sup.2/g
and more preferably of at least 100 m.sup.2/g. It is also desired
that the pore size distribution of the bulk metal hydrotreating
catalysts be approximately the same as the one of conventional
hydrotreating catalysts. Bulk metal hydrotreating catalysts have a
pore volume of 0.05-5 ml/g, or of 0.1-4 ml/g, or of 0.1-3 ml/g, or
of 0.1-2 ml/g determined by nitrogen adsorption. Preferably, pores
smaller than 1 nm are not present. The bulk metal hydrotreating
catalysts can have a median diameter of at least 50 nm, or at least
100 nm. The bulk metal hydrotreating catalysts can have a median
diameter of not more than 5000 .mu.m, or not more than 3000 .mu.m.
In an embodiment, the median particle diameter lies in the range of
0.1-50 .mu.m and most preferably in the range of 0.5-50 .mu.m.
Process Conditions--Dewaxing
[0056] In some aspects, a dewaxing catalyst may also be included in
a reaction system for dewaxing a hydrotreated effluent or liquid
product. Typically, the dewaxing catalyst is located in a bed
downstream from any hydrotreating catalyst stages and/or any
hydrotreating catalyst present in a stage. This can allow the
dewaxing to occur on molecules that have already been hydrotreated
to remove a significant fraction of organic sulfur- and
nitrogen-containing species. In some configurations, the effluent
from a reactor containing hydrotreating catalyst, optionally after
a gas-liquid separation, can be fed into a separate stage or
reactor containing the dewaxing catalyst.
[0057] Suitable dewaxing catalysts can include molecular sieves
such as crystalline aluminosilicates (zeolites). In an embodiment,
the molecular sieve can comprise, consist essentially of, or be
ZSM-5, ZSM-22, ZSM-23, ZSM-35, ZSM-48, zeolite Beta. ZSM-57, or a
combination thereof, for example ZSM-23 and/or ZSM-48, or ZSM-48
and/or zeolite Beta. Optionally but preferably, molecular sieves
that are selective for dewaxing by isomerization as opposed to
cracking can be used, such as ZSM-48, zeolite Beta, ZSM-23, or a
combination thereof. Additionally or alternately, the molecular
sieve can comprise, consist essentially of, or be a 10-member ring
1-D molecular sieve. Examples include EU-1, ZSM-35 (or ferrierite),
ZSM-1, ZSM-57, NU-87, SAPO-11, ZSM-48, ZSM-23, and ZSM-22.
Preferred materials are EU-2, EU-11, ZBM-30, ZSM-48, or ZSM-23.
ZSM-48 is most preferred. Note that a zeolite having the ZSM-23
structure with a silica to alumina ratio of from about 20:1 to
about 40:1 can sometimes be referred to as SSZ-32. Other molecular
sieves that are isostructural with the above materials include
Theta-1, NU-10, EU-13, KZ-1, and NU-23. Optionally but preferably,
the dewaxing catalyst can include a binder for the molecular sieve,
such as alumina, titania, silica, silica-alumina, zirconia, or a
combination thereof, for example alumina and/or titania or silica
and/or zirconia and/or titania.
[0058] Preferably, the dewaxing catalysts used in processes
according to the invention are catalysts with a low ratio of silica
to alumina. For example, for ZSM-48, the ratio of silica to alumina
in the zeolite can be less than 200:1, or less than 110:1, or less
than 100:1, or less than 90:1, or less than 80:1. In various
embodiments, the ratio of silica to alumina can be from 30:1 to
200:1, 60:1 to 110:1, or 70:1 to 100:1.
[0059] In various embodiments, the catalysts according to the
invention further include a metal hydrogenation component. The
metal hydrogenation component is typically a Group VI and/or a
Group VIII metal. Preferably, the metal hydrogenation component is
a Group VIII noble metal. Preferably, the metal hydrogenation
component is Pt, Pd, or a mixture thereof. In an alternative
preferred embodiment, the metal hydrogenation component can be a
combination of a non-noble Group VIII metal with a Group VI metal.
Suitable combinations can include Ni, Co, or Fe with Mo or W,
preferably Ni with Mo or W.
[0060] The metal hydrogenation component may be added to the
catalyst in any convenient manner. One technique for adding the
metal hydrogenation component is by incipient wetness. For example,
after combining a zeolite and a binder, the combined zeolite and
binder can be extruded into catalyst particles. These catalyst
particles can then be exposed to a solution containing a suitable
metal precursor. Alternatively, metal can be added to the catalyst
by ion exchange, where a metal precursor is added to a mixture of
zeolite (or zeolite and binder) prior to extrusion.
[0061] The amount of metal in the catalyst can be at least 0.1 wt %
based on catalyst, or at least 0.15 wt %, or at least 0.2 wt %, or
at least 0.25 wt %, or at least 0.3 wt %, or at least 0.5 wt %
based on catalyst. The amount of metal in the catalyst can be 20 wt
% or less based on catalyst, or 10 wt % or less, or 5 wt % or less,
or 2.5 wt % or less, or 1 wt % or less. For embodiments where the
metal is Pt, Pd, another Group VIII noble metal, or a combination
thereof, the amount of metal can be from 0.1 to 5 wt %, preferably
from 0.1 to 2 wt %, or 0.25 to 1.8 wt %, or 0.4 to 1.5 wt %. For
embodiments where the metal is a combination of a non-noble Group
VIII metal with a Group VI metal, the combined amount of metal can
be from 0.5 wt % to 20 wt %, or 1 wt % to 15 wt %, or 2.5 wt % to
10 wt %.
[0062] Dewaxing catalysts can also include a binder. In some
embodiments, the dewaxing catalysts used in process according to
the invention are formulated using a low surface area binder, a low
surface area binder represents a binder with a surface area of 100
m.sup.2/g or less, or 80 m.sup.2/g or less, or 70 m.sup.2/g or
less.
[0063] A zeolite can be combined with binder in any convenient
manner. For example, a bound catalyst can be produced by starting
with powders of both the zeolite and binder, combining and mulling
the powders with added water to form a mixture, and then extruding
the mixture to produce a bound catalyst of a desired size.
Extrusion aids can also be used to modify the extrusion flow
properties of the zeolite and binder mixture. The amount of
framework alumina in the catalyst may range from 0.1 to 3.33 wt %,
or 0.1 to 2.7 wt %, or 0.2 to 2 wt %, or 0.3 to 1 wt %.
[0064] In yet another embodiment, a binder composed of two or more
metal oxides can also be used. In such an embodiment, the weight
percentage of the low surface area binder is preferably greater
than the weight percentage of the higher surface area binder.
Alternatively, if both metal oxides used for forming a mixed metal
oxide binder have a sufficiently low surface area, the proportions
of each metal oxide in the binder are less important. When two or
more metal oxides are used to form a binder, the two metal oxides
can be incorporated into the catalyst by any convenient method. For
example, one binder can be mixed with the zeolite during formation
of the zeolite powder, such as during spray drying. The spray dried
zeolite/binder powder can then be mixed with the second metal oxide
binder prior to extrusion. In yet another embodiment, the dewaxing
catalyst is self-bound and does not contain a binder.
[0065] A bound dewaxing catalyst can also be characterized by
comparing the micropore (or zeolite) surface area of the catalyst
with the total surface area of the catalyst. These surface areas
can be calculated based on analysis of nitrogen porosimetry data
using the BET method for surface area measurement. Previous work
has shown that the amount of zeolite content versus binder content
in catalyst can be determined from BET measurements (see, e.g.,
Johnson, M. F. L., Jour. Catal., (1978) 52, 425). The micropore
surface area of a catalyst refers to the amount of catalyst surface
area provided due to the molecular sieve and/or the pores in the
catalyst in the BET measurements. The total surface area represents
the micropore surface plus the external surface area of the bound
catalyst. In one embodiment, the percentage of micropore surface
area relative to the total surface area of a bound catalyst can be
at least about 35%, for example at least about 38%, at least about
40%, or at least about 45%. Additionally or alternately, the
percentage of micropore surface area relative to total surface area
can be about 65% or less, for example about 60% or less, about 55%
or less, or about 50% or less.
[0066] Additionally or alternately, the dewaxing catalyst can
comprise, consist essentially of, or be a catalyst that has not
been dealuminated. Further additionally or alternately, the binder
for the catalyst can include a mixture of binder materials
containing alumina.
[0067] Process conditions in a catalytic dewaxing zone can include
a temperature of about 200.degree. C. to about 450.degree. C.,
preferably about 270.degree. C. to about 400.degree. C., a hydrogen
partial pressure of about 1.8 MPag to about 34.6 MPag (250 psig to
5000 psig), preferably about 4.8 MPag to about 20.8 MPag, and a
hydrogen treat gas rate of about 35.6 m.sup.3/m.sup.3 (200 SCF/B)
to about 1781 m.sup.3/m.sup.3 (10,000 scf/B), preferably about 178
m.sup.3/m.sup.3 (1000 SCF/B) to about 890.6 m.sup.3/m.sup.3 (5000
SCF/B). In still other embodiments, the conditions can include
temperatures in the range of about 600.degree. F. (343.degree. C.)
to about 815.degree. F. (435.degree. C.), hydrogen partial
pressures of from about 500 psig to about 3000 psig (3.5 MPag-20.9
MPag), and hydrogen treat gas rates of from about 213
m.sup.3/m.sup.3 to about 1068 m.sup.3/m.sup.3 (1200 SCF. The LHSV
can be from about 0.1 h.sup.-1 to about 10 h.sup.-1, such as from
about 0.5 h.sup.-1 to about 5 h.sup.-1 and/or from about 1 h.sup.-1
to about 4 h.sup.-1.
Process Conditions--Hydrofinishing and/or Aromatic Saturation
Processes
[0068] In various aspects, a hydrofinishing stage, an aromatic
saturation stage, or a hydrofinishing and an aromatic saturation
stage may also be provided. The hydrofinishing and/or aromatic
saturation stage(s) or reaction zones can occur after the last
hydrotreating stage, and before and/or after any hydrocracking or
dewaxing stages. The hydrofinishing and/or aromatic saturation can
occur either before or after fractionation. If hydrofinishing
and/or aromatic saturation occurs after fractionation, the
hydrofinishing can be performed on one or more portions of the
fractionated product, such as being performed on one or more
lubricant base oil portions. Alternatively, the entire effluent
from the last hydrocracking or dewaxing process can be
hydrofinished and/or undergo aromatic saturation.
[0069] In some situations, a hydrofinishing process and an aromatic
saturation process can refer to a single process performed using
the same catalyst. Alternatively, one type of catalyst or catalyst
system can be provided to perform aromatic saturation, while a
second catalyst or catalyst system can be used for hydrofinishing.
As still another alternative, aromatic saturation sometimes refers
to a higher temperature range of processing than a hydrofinishing
process. In such an alternative, a hydrofinishing process may be
suitable for removing (for example) color bodies from a product,
but otherwise result in a lower amount of aromatic saturation than
an aromatic saturation process. Typically a hydrofinishing and/or
aromatic saturation process will be performed in a separate reactor
from dewaxing or hydrocracking processes for practical reasons,
such as facilitating use of a lower temperature for the
hydrofinishing or aromatic saturation process.
[0070] Hydrofinishing and/or aromatic saturation catalysts can
include catalysts containing Group VI metals, Group VIII metals,
and mixtures thereof. In an embodiment, preferred metals include at
least one metal sulfide having a strong hydrogenation function. In
another embodiment, the hydrofinishing catalyst can include a Group
VIII noble metal, such as Pt, Pd, or a combination thereof. The
mixture of metals may also be present as bulk metal catalysts
wherein the amount of metal is about 30 wt. % or greater based on
catalyst. Suitable metal oxide supports include low acidic oxides
such as silica, alumina, silica-aluminas or titania, preferably
alumina. The preferred hydrofinishing catalysts for aromatic
saturation can comprise at least one metal having relatively strong
hydrogenation function on a porous support. The support materials
may also be modified, such as by halogenation, or in particular
fluorination. The metal content of the catalyst is often as high as
about 20 weight percent for non-noble metals. In some optional
aspects, hydrotreating catalysts as described above can be used as
hydrotreating catalysts. In other optional aspects, a preferred
hydrofinishing catalyst can include a crystalline material
belonging to the M41S class or family of catalysts. The M41S family
of catalysts are mesoporous materials having high silica content.
Examples include MCM-41, MCM-48 and MCM-50. A preferred member of
this class is MCM-41. If separate catalysts are used for aromatic
saturation and hydrofinishing, an aromatic saturation catalyst can
be selected based on activity and/or selectivity for aromatic
saturation, while a hydrofinishing catalyst can be selected based
on activity for improving product specifications, such as product
color and polynuclear aromatic reduction.
[0071] Hydrofinishing conditions can include temperatures from
about 125.degree. C. to about 425.degree. C., preferably about
180.degree. C. to about 280.degree. C., total pressures from about
500 psig (3.4 MPa) to about 3000 psig (20.7 MPa), preferably about
1500 psig (10.3 MPa) to about 2500 psig (17.2 MPa), and liquid
hourly space velocity from about 0.1 hr.sup.-1 to about 5 hr.sup.-1
LHSV, preferably about 0.5 h.sup.-1 to about 1.5 hr.sup.-1.
[0072] In aspects where aromatic saturation is contemplated as a
distinct process from hydrofinishing, aromatic saturation
conditions can include temperatures from about 175.degree. C. to
about 425.degree. C., or about 200.degree. C. to about 425.degree.
C., preferably about 225.degree. C. to about 325.degree. C., or
about 225.degree. C. to about 280.degree. C., total pressures from
about 500 psig (3.4 MPa) to about 3000 psig (20.7 MPa), preferably
about 1500 psig (10.3 MPa) to about 2500 psig (17.2 MPa), and
liquid hourly space velocity from about 0.1 hr.sup.-1 to about 5
hr.sup.-1 LHSV, preferably about 0.5 hr.sup.-1 to about 1.5
hr.sup.-1.
Alternative Configurations--Hydrocracking Conditions
[0073] In some alternative configurations, the plurality of
hydrotreating stages described above, including separation between
the stages, can be used to prepare a feed for subsequent
hydrocracking for further conversion of the feed. Hydrocracking
catalysts typically contain sulfided base metals on acidic
supports, such as amorphous silica alumina, cracking zeolites or
other cracking molecular sieves such as USY, or acidified alumina.
In some preferred aspects, a hydrocracking catalyst can include at
least one molecular sieve, such as a zeolite. Often these acidic
supports are mixed or bound with other metal oxides such as
alumina, titania or silica. Non-limiting examples of supported
catalytic metals for hydrocracking catalysts include nickel,
nickel-cobalt-molybdenum, cobalt-molybdenum, nickel-tungsten,
nickel-molybdenum, and/or nickel-molybdenum-tungsten. Additionally
or alternately, hydrocracking catalysts with noble metals can also
be used. Non-limiting examples of noble metal catalysts include
those based on platinum and/or palladium. Support materials which
may be used for both the noble and non-noble metal catalysts can
comprise a refractory oxide material such as alumina, silica,
alumina-silica, kieselguhr, diatomaceous earth, magnesia, zirconia,
or combinations thereof, with alumina, silica, alumina-silica being
the most common (and preferred, in one embodiment).
[0074] In some aspects, a hydrocracking catalyst can include a
large pore molecular sieve that is selective for cracking of
branched hydrocarbons and/or cyclic hydrocarbons. Zeolite Y, such
as ultrastable zeolite Y (USY) is an example of a zeolite molecular
sieve that is selective for cracking of branched hydrocarbons and
cyclic hydrocarbons. Depending on the aspect, the silica to alumina
ratio in a USY zeolite can be at least about 10, such as at least
about 15, or at least about 25, or at least about 50, or at least
about 100. Depending on the aspect, the unit cell size for a USY
zeolite can be about 24.50 Angstroms or less, such as about 24.45
Angstroms or less, or about 24.40 Angstroms or less, or about 24.35
Angstroms or less, such as about 24.30 Angstroms.
[0075] In various embodiments, the conditions selected for
hydrocracking can depend on the desired level of conversion, the
level of contaminants in the input feed to the hydrocracking stage,
and potentially other factors. A hydrocracking process performed
under sour conditions, such as conditions where the sulfur content
of the input feed to the hydrocracking stage is at least 500 wppm,
can be carried out at temperatures of about 550.degree. F.
(288.degree. C.) to about 840.degree. F. (449.degree. C.), hydrogen
partial pressures of from about 250 psig to about 5000 psig (1.8
MPag to 34.6 MPag), liquid hourly space velocities of from 0.05
h.sup.-1 to 10 h.sup.-1, and hydrogen treat gas rates of from 35.6
m.sup.3/m.sup.3 to 1781 m.sup.3/m.sup.3 (200 SCF/B to 10,000
SCF/B). In other embodiments, the conditions can include
temperatures in the range of about 600.degree. F. (343.degree. C.)
to about 815.degree. F. (435.degree. C.), hydrogen partial
pressures of from about 500 psig to about 3000 psig (3.5 MPag-20.9
MPag), liquid hourly space velocities of from about 0.2 h.sup.-1 to
about 2 h.sup.-1 and hydrogen treat gas rates of from about 213
m.sup.3/m.sup.3 to about 1068 m.sup.3/m.sup.3 (1200 SCF/B to 6000
SCF/B).
[0076] A hydrocracking process performed under non-sour conditions
can be performed under conditions similar to those used for sour
conditions, or the conditions can be different. Alternatively, a
non-sour hydrocracking stage can have less severe conditions than a
similar hydrocracking stage operating under sour conditions.
Suitable hydrocracking conditions can include temperatures of about
550.degree. F. (288.degree. C.) to about 840.degree. F.
(449.degree. C.), hydrogen partial pressures of from about 250 psig
to about 5000 psig (1.8 MPag to 34.6 MPag), liquid hourly space
velocities of from 0.05 h.sup.-1 to 10 h.sup.-1, and hydrogen treat
gas rates of from 35.6 m.sup.3/m.sup.3 to 1781 m.sup.3/m.sup.3 (200
SCF/B to 10,000 SCF/B). In other embodiments, the conditions can
include temperatures in the range of about 600.degree. F.
(343.degree. C.) to about 815.degree. F. (435.degree. C.), hydrogen
partial pressures of from about 500 psig to about 3000 psig (3.5
MPag-20.9 MPag), liquid hourly space velocities of from about 0.2
h.sup.-1 to about 2 h.sup.-1 and hydrogen treat gas rates of from
about 213 m.sup.3/m.sup.3 to about 1068 m.sup.3/m.sup.3 (1200 SCF/B
to 6000 SCF/B).
[0077] After such a hydrocracking process, a suitable feed can
undergo further additional processing, such as dewaxing and/or
hydrofinishing and/or aromatic saturation. This type of process can
be suitable for formation of both distillate fuel and lubricant
base oil products with increased yield.
Multimetallic Catalyst and Forming Multimetallic Catalyst from a
Precursor
[0078] As used herein, the term "bulk", when describing a mixed
metal oxide catalyst composition, indicates that the catalyst
composition is self-supporting in that it does not require a
carrier or support. It is well understood that bulk catalysts may
have some minor amount of carrier or support material in their
compositions (e.g., about 20 wt % or less, about 15 wt % or less,
about 10 wt % or less, about 5 wt % or less, or substantially no
carrier or support, based on the total weight of the catalyst
composition); for instance, bulk hydroprocessing catalysts may
contain a minor amount of a binder, e.g., to improve the physical
and/or thermal properties of the catalyst. In contrast,
heterogeneous or supported catalyst systems typically comprise a
carrier or support onto which one or more catalytically active
materials are deposited, often using an impregnation or coating
technique. Nevertheless, heterogeneous catalyst systems without a
carrier or support (or with a minor amount of carrier or support)
are generally referred to as bulk catalysts and are frequently
formed by co-precipitation or solid-solid reactions in
slurries.
[0079] In some aspects, the methods described herein can include
use of a catalyst formed from a catalyst precursor composition
comprising at least one metal from Group 6 of the Periodic Table of
the Elements, at least one metal from Groups 8-10 of the Periodic
Table of the Elements, and a reaction product formed from (i) a
first organic compound containing at least one amine group and at
least 10 carbons or (ii) a second organic compound containing at
least one carboxylic acid group and at least 10 carbons, but not
both (i) and (ii), wherein the reaction product contains additional
unsaturated carbon atoms, relative to (i) the first organic
compound or (ii) the second organic compound, wherein the metals of
the catalyst precursor composition are arranged in a crystal
lattice, and wherein the reaction product is not located within the
crystal lattice. This catalyst precursor composition can be a bulk
metal catalyst precursor composition or a supported metal catalyst
precursor composition. When it is a bulk mixed metal catalyst
precursor composition, the reaction product can be obtained by
heating the composition (though specifically the amine-containing
compound or the carboxylic acid-containing compound) to a
temperature from about 195.degree. C. to about 260.degree. C. for a
time sufficient for the first or second organic compounds to react
to form additional in situ unsaturated carbon atoms and/or become
more oxidized than the first or second organic compounds, but not
for so long that more than 50% by weight of the first or second
organic compound is volatilized, thereby forming a catalyst
precursor composition that contains in situ formed unsaturated
carbon atoms and/or that is further oxidized.
[0080] Other aspects can relate to using a catalyst formed from a
catalyst precursor composition containing in situ formed
unsaturated carbon atoms. The catalyst can be formed from the
precursor by a process comprising: (a) treating a catalyst
precursor composition comprising at least one metal from Group 6 of
the Periodic Table of the Elements, at least one metal from Groups
8-10 of the Periodic Table of the Elements, with a first organic
compound containing at least one amine group and at least 10 carbon
atoms or a second organic compound containing at least one
carboxylic acid group and at least 10 carbon atoms, to form an
organically treated precursor catalyst composition; and (b) heating
said organically treated precursor catalyst composition at a
temperature from about 195.degree. C. to about 260.degree. C. for a
time sufficient for the first or second organic compounds to react
to form additional in situ unsaturated carbon atoms and/or become
more oxidized, but not for so long that more than 50% by weight of
the first or second organic compound is volatilized, thereby
forming a catalyst precursor composition that contains in situ
formed unsaturated carbon atoms and/or that is further oxidized.
This process can be used to make a bulk metal catalyst precursor
composition or a supported metal catalyst precursor composition.
When used to make a bulk mixed metal catalyst precursor
composition, the catalyst precursor composition containing in situ
formed unsaturated carbon atoms can, in one embodiment, consist
essentially of the reaction product, an oxide form of the at least
one metal from Group 6, an oxide form of the at least one metal
from Groups 8-10, and optionally about 20 wt % or less of a
binder.
[0081] As an example, when the catalyst precursor is a bulk mixed
metal catalyst precursor composition, the reaction product can be
obtained by heating the composition (though specifically the first
or second organic compounds, or the amine-containing or carboxylic
acid-containing compound) to a temperature from about 195.degree.
C. to about 260.degree. C. for a time sufficient to effectuate a
dehydrogenation, and/or an at least partial decomposition, of the
first or second organic compound to form an additional unsaturation
and/or additional oxidation in the reaction product in situ.
Accordingly, a bulk mixed metal hydroprocessing catalyst
composition can be produced from this bulk mixed metal catalyst
precursor composition by sulfiding it under sufficient sulfiding
conditions, which sulfiding should begin in the presence of the in
situ additionally unsaturated reaction product (which may result
from at least partial decomposition, e.g., via oxidative
dehydrogenation in the presence of oxygen and/or via non-oxidative
dehydrogenation in the absence of an appropriate concentration of
oxygen, of typically-unfunctionalized organic portions of the first
or second organic compounds, e.g., of an aliphatic portion of an
organic compound and/or through conjugation/aromatization of
unsaturations expanding upon an unsaturated portion of an organic
compound).
[0082] In still other aspects, a feed can be processed in a
reaction system that includes a catalyst formed from a catalyst
precursor composition comprising at least one metal from Group 6 of
the Periodic Table of the Elements, at least one metal from Groups
8-10 of the Periodic Table of the Elements, and a reaction product
formed from (i) a first organic compound containing at least one
amine group, and (ii) a second organic compound separate from said
first organic compound and containing at least one carboxylic acid
group. When this reaction product is an amide, the presence of the
reaction product in any intermediate or final composition can be
determined by methods well known in the art, e.g., by infrared
spectroscopy (FTIR) techniques. When this reaction product contains
additional unsaturation(s) not present in the first and second
organic compounds, e.g., from at least partial
decomposition/dehydrogenation at conditions including elevated
temperatures, the presence of the additional unsaturation(s) in any
intermediate or final composition can be determined by methods well
known in the art, e.g., by FTIR and/or nuclear magnetic resonance
(.sup.13C NMR) techniques. This catalyst precursor composition can
be a bulk metal catalyst precursor composition or a heterogeneous
(supported) metal catalyst precursor composition.
[0083] More broadly, this type of aspect relates to use of a
catalyst formed from a catalyst precursor composition comprising at
least one metal from Group 6 of the Periodic Table of the Elements,
at least one metal from Groups 8-10 of the Periodic Table of the
Elements, and a condensation reaction product formed from (i) a
first organic compound containing at least one first functional
group, and (ii) a second organic compound separate from said first
organic compound and containing at least one second functional
group, wherein said first functional group and said second
functional group are capable of undergoing a condensation reaction
and/or a (decomposition) reaction causing an additional
unsaturation to form an associated product. Though the description
above and herein often refers specifically to the condensation
reaction product being an amide, it should be understood that any
in situ condensation reaction product formed can be substituted for
the amide described herein. For example, if the first functional
group is a hydroxyl group and the second functional group is a
carboxylic acid or an acid chloride or an organic ester capable of
undergoing transesterification with the hydroxyl group, then the in
situ condensation reaction product formed would be an ester.
[0084] As an example, when the catalyst precursor is a bulk mixed
metal catalyst precursor composition, the reaction product can be
obtained by heating the composition (such as the condensation
reactants, or the amine-containing compound and/or the carboxylic
acid-containing compound) to a temperature from about 195.degree.
C. to about 260.degree. C. for a time sufficient for the first and
second organic compounds to form a condensation product, such as an
amide, and/or an additional (decomposition) unsaturation in situ.
Accordingly, a bulk mixed metal hydroprocessing catalyst
composition can be produced from this bulk mixed metal catalyst
precursor composition by sulfiding it under sufficient sulfiding
conditions, which sulfiding should begin in the presence of the in
situ product, e.g., the amide (i.e., when present, the condensation
product moiety, or amide, can be substantially present and/or can
preferably not be significantly decomposed by the beginning of the
sulfiding step), and/or containing additional unsaturations (which
may result from at least partial decomposition, e.g., via oxidative
dehydrogenation in the presence of oxygen and/or via non-oxidative
dehydrogenation in the absence of an appropriate concentration of
oxygen, of typically-unfunctionalized organic portions of the first
and/or second organic compounds, e.g., of an aliphatic portion of
an organic compound and/or through conjugation/aromatization of
unsaturations expanding upon an unsaturated portion of an organic
compound or stemming from an interaction of the first and second
organic compounds at a site other than their respective functional
groups).
[0085] In yet other aspects, a feed can be processed using a
catalyst formed from a catalyst precursor composition containing an
ex-situ formed reaction product. The catalyst can be formed from
the precursor by a process comprising: (a) treating a catalyst
precursor composition comprising at least one metal from Group 6 of
the Periodic Table of the Elements, at least one metal from Groups
8-10 of the Periodic Table of the Elements, with an
amide-containing reaction product formed from a first organic
compound containing at least one amine group and at least 10 carbon
atoms or a second organic compound containing at least one
carboxylic acid group and at least 10 carbon atoms, to form an
organically treated precursor catalyst composition; and (b) heating
said organically treated precursor catalyst composition at a
temperature from about 195.degree. C. to about 260.degree. C. for a
time sufficient for the amide-containing reaction product to form
additional in situ unsaturated carbon atoms and/or become more
oxidized, but not for so long that more than 50% by weight of the
first or second organic compound is volatilized, thereby forming a
catalyst precursor composition that contains in situ formed
unsaturated carbon atoms and/or that is further oxidized. This
process can be used to make a bulk metal catalyst precursor
composition or a supported metal catalyst precursor composition.
When used to make a bulk mixed metal catalyst precursor
composition, the catalyst precursor composition can, in one
embodiment, consist essentially of the reaction product containing
further unsaturated carbon atoms and/or further oxidation, an oxide
form of the at least one metal from Group 6, an oxide form of the
at least one metal from Groups 8-10, and optionally about 20 wt %
or less of a binder.
[0086] When the catalyst precursor is a bulk mixed metal catalyst
precursor composition, the thermal treatment of the
amide-impregnated metal oxide component is carried out by heating
the impregnated composition to a temperature and for a time which
does not result in gross decomposition of the amide, although
additional unsaturation may arise from partial in situ
decomposition; the temperature is typically from about 195.degree.
C. to about 250.degree. C. (or optionally about 195.degree. C. to
about 260.degree. C.), but higher temperatures, e.g. in the range
of 250 to 280.degree. C., can be used in order to abbreviate the
duration of the heating although due care is required to avoid the
gross decomposition of the pre-formed amide, as discussed further
below. The bulk mixed metal hydroprocessing catalyst can be
produced from this precursor by sulfiding it with the sulfiding
taking place with the amide present on the metal oxide component
(i.e., when the thermally treated amide, is substantially present
and/or preferably not significantly decomposed by the beginning of
the sulfiding step). Additional unsaturation may be present in the
organic component of the catalyst precursor resulting from a
variety of mechanisms including partial decomposition, (e.g., via
oxidative dehydrogenation in the presence of oxygen and/or via
non-oxidative dehydrogenation in the absence of an appropriate
concentration of oxygen), of typically-unfunctionalized organic
portions of the amide and/or through conjugation/aromatization of
unsaturations expanding upon an unsaturated portion the amide. The
treated organic component may also contain additional oxygen in
addition to the unsaturation when the treatment is carried out in
an oxidizing atmosphere.
[0087] Catalyst precursor compositions and hydroprocessing catalyst
compositions useful in various aspects of the present invention can
advantageously comprise (or can have metal components that consist
essentially of) at least one metal from Group 6 of the Periodic
Table of Elements and at least one metal from Groups 8-10 of the
Periodic Table of Elements, and optionally at least one metal from
Group 5 of the Periodic Table of Elements. Generally, these metals
are present in their substantially fully oxidized form, which can
typically take the form of simple metal oxides, but which may be
present in a variety of other oxide forms, e.g., such as
hydroxides, oxyhydroxides, oxycarbonates, carbonates, oxynitrates,
oxysulfates, or the like, or some combination thereof. In one
preferred embodiment, the Group 6 metal(s) can be Mo and/or W, and
the Group 8-10 metal(s) can be Co and/or Ni. Generally, the atomic
ratio of the Group 6 metal(s) to the metal(s) of Groups 8-10 can be
from about 2:1 to about 1:3, for example from about 5:4 to about
1:2, from about 5:4 to about 2:3, from about 5:4 to about 3:4, from
about 10:9 to about 1:2, from about 10:9 to about 2:3, from about
10:9 to about 3:4, from about 20:19 to about 2:3, or from about
20:19 to about 3:4. When the composition further comprises at least
one metal from Group 5, that at least one metal can be V and/or Nb.
When present, the amount of Group 5 metal(s) can be such that the
atomic ratio of the Group 6 metal(s) to the Group 5 metal(s) can be
from about 99:1 to about 1:1, for example from about 99:1 to about
5:1, from about 99:1 to about 10:1, or from about 99:1 to about
20:1. Additionally or alternately, when Group 5 metal(s) is(are)
present, the atomic ratio of the sum of the Group 5 metal(s) plus
the Group (6) metal(s) compared to the metal(s) of Groups 8-10 can
be from about 2:1 to about 1:3, for example from about 5:4 to about
1:2, from about 5:4 to about 2:3, from about 5:4 to about 3:4, from
about 10:9 to about 1:2, from about 10:9 to about 2:3, from about
10:9 to about 3:4, from about 20:19 to about 2:3, or from about
20:19 to about 3:4.
[0088] The metals in the catalyst precursor compositions and in the
hydroprocessing catalyst compositions according to the invention
can be present in any suitable form prior to sulfiding, but can
often be provided as metal oxides. When provided as bulk mixed
metal oxides, such bulk oxide components of the catalyst precursor
compositions and of the hydroprocessing catalyst compositions
according to the invention can be prepared by any suitable method
known in the art, but can generally be produced by forming a
slurry, typically an aqueous slurry, comprising (1) (a) an oxyanion
of the Group 6 metal(s), such as a tungstate and/or a molybdate, or
(b) an insoluble (oxide, acid) form of the Group 6 metal(s), such
as tungstic acid and/or molybdenum trioxide, (2) a salt of the
Group 8-10 metal(s), such as nickel carbonate, and optionally, when
present, (3) (a) a salt or oxyanion of a Group 5 metal, such as a
vanadate and/or a niobate, or (b) insoluble (oxide, acid) form of a
Group 5 metal, such as niobic acid and/or diniobium pentoxide. The
slurry can be heated to a suitable temperature, such as from about
60.degree. C. to about 150.degree. C., at a suitable pressure,
e.g., at atmospheric or autogenous pressure, for an appropriate
time, e.g., about 4 hours to about 24 hours.
[0089] Non-limiting examples of suitable mixed metal oxide
compositions can include, but are not limited to, nickel-tungsten
oxides, cobalt-tungsten oxides, nickel-molybdenum oxides,
cobalt-molybdenum oxides, nickel-molybdenum-tungsten oxides,
cobalt-molybdenum-tungsten oxides, cobalt-nickel-tungsten oxides,
cobalt-nickel-molybdenum oxides, cobalt-nickel-tungsten-molybdenum
oxides, nickel-tungsten-niobium oxides, nickel-tungsten-vanadium
oxides, cobalt-tungsten-vanadium oxides, cobalt-tungsten-niobium
oxides, nickel-molybdenum-niobium oxides,
nickel-molybdenum-vanadium oxides,
nickel-molybdenum-tungsten-niobium oxides,
nickel-molybdenum-tungsten-vanadium oxides, and the like, and
combinations thereof.
[0090] Suitable mixed metal oxide compositions can advantageously
exhibit a specific surface area (as measured via the nitrogen BET
method using a Quantachrome Autosorb.TM. apparatus) of at least
about 20 m.sup.2/g, for example at least about 30 m.sup.2/g, at
least about 40 m.sup.2/g, at least about 50 m.sup.2/g, at least
about 60 m.sup.2/g, at least about 70 m.sup.2/g, or at least about
80 m.sup.2/g. Additionally or alternately, the mixed metal oxide
compositions can exhibit a specific surface area of not more than
about 500 m.sup.2/g, for example not more than about 400 m.sup.2/g,
not more than about 300 m.sup.2/g, not more than about 250
m.sup.2/g, not more than about 200 m.sup.2/g, not more than about
175 m.sup.2/g, not more than about 150 m.sup.2/g, not more than
about 125 m.sup.2/g, or not more than about 100 m.sup.2/g.
[0091] In some aspects, after separating and drying the mixed metal
oxide (slurry) composition, it can be treated, generally by
impregnation, with (i) an effective amount of a first organic
compound containing at least one amine group or (ii) an effective
amount of a second organic compound separate from the first organic
compound and containing at least one carboxylic acid group, but not
both (i) and (ii).
[0092] In other aspects, after separating and drying the mixed
metal oxide (slurry) composition, it can be treated, generally by
impregnation, with (i) an effective amount of a first organic
compound containing at least one amine group, and (ii) an effective
amount of a second organic compound separate from the first organic
compound and containing at least one carboxylic acid group.
[0093] In still other aspects, after separating and drying the
mixed metal oxide (slurry) composition, it can be treated,
generally by impregnation, with the pre-formed amide derived from
(i) an effective amount of a first organic compound containing at
least one amine group, and (ii) an effective amount of a second
organic compound separate from the first organic compound and
containing at least one carboxylic acid group. The amide is formed
by a condensation reaction between the amine reactant and the
carboxylic acid reactant; this reaction, carried out ex situ, is
usually accomplished at mildly elevated temperatures.
[0094] In aspects where either a first or second organic compound
is used, the first organic compound can comprise at least 10 carbon
atoms, for example can comprise from 10 to 20 carbon atoms or can
comprise a primary monoamine having from 10 to 30 carbon atoms.
Additionally or alternately, the second organic compound can
comprise at least 10 carbon atoms, for example can comprise from 10
to 20 carbon atoms or can comprise only one carboxylic acid group
and can have from 10 to 30 carbon atoms.
[0095] In other aspects where both a first and second organic
compound are used (including aspects where a first and second
organic compound are reacted ex situ to form an amide), the first
organic compound can comprise at least 10 carbon atoms, for example
can comprise from 10 to 20 carbon atoms or can comprise a primary
monoamine having from 10 to 30 carbon atoms. Additionally or
alternately, the second organic compound can comprise at least 10
carbon atoms, for example can comprise from 10 to 20 carbon atoms
or can comprise only one carboxylic acid group and can have from 10
to 30 carbon atoms. Further additionally or alternately, the total
number of carbon atoms comprised among both the first and second
organic compounds can be at least 15 carbon atoms, for example at
least 20 carbon atoms, at least 25 carbon atoms, at least 30 carbon
atoms, or at least 35 carbon atoms. Although in such embodiments
there may be no practical upper limit on total carbon atoms from
both organic compounds, in some embodiments, the total number of
carbon atoms comprised among both the first and second organic
compounds can be 100 carbon atoms or less, for example 80 carbon
atoms or less, 70 carbon atoms or less, 60 carbon atoms or less, or
50 carbon atoms or less.
[0096] Representative examples of organic compounds containing
amine groups can include, but are not limited to, primary and/or
secondary, linear, branched, and/or cyclic amines, such as
triacontanylamine, octacosanylamine, hexacosanylamine,
tetracosanylamine, docosanylamine, erucylamine, eicosanylamine,
octadecylamine, oleylamine, linoleylamine, hexadecylamine,
sapienylamine, palmitoleylamine, tetradecylamine, myristoleylamine,
dodecylamine, decylamine, nonylamine, cyclooctylamine, octylamine,
cycloheptylamine, heptylamine, cyclohexylamine, n-hexylamine,
isopentylamine, n-pentylamine, t-butylamine, n-butylamine,
isopropylamine, n-propylamine, adamantanamine,
adamantanemethylamine, pyrrolidine, piperidine, piperazine,
imidazole, pyrazole, pyrrole, pyrrolidine, pyrroline, indazole,
indole, carbazole, norbornylamine, aniline, pyridylamine,
benzylamine, aminotoluene, alanine, arginine, aspartic acid,
glutamic acid, glutamine, glycine, histidine, isoleucine, leucine,
lysine, phenylalanine, serine, threonine, valine,
1-amino-2-propanol, 2-amino-1-propanol, diaminoeicosane,
diaminooctadecane, diaminohexadecane, diaminotetradecane,
diaminododecane, diaminodecane, 1,2-diaminocyclohexane,
1,3-diaminocyclohexane, 1,4-diaminocyclohexane, ethylenediamine,
ethanolamine, p-phenylenediamine, o-phenylenediamine,
m-phenylenediamine, 1,2-propylenediamine, 1,3-propylenediamine,
1,4-diaminobutane, 1,3diamino-2-propanol, and the like, and
combinations thereof. In an embodiment, the molar ratio of the
Group 6 metal(s) in the composition to the first organic compound
during treatment can be from about 1:1 to about 20:1.
[0097] Additionally or alternately, in some aspects the amine
portion of the first organic compound can be a part of a larger
functional group in that compound, so long as the amine portion
(notably the amine nitrogen and the constituents attached thereto)
retains its operability as a Lewis base. For instance, the first
organic compound can comprise a urea, which functional group
comprises an amine portion attached to the carbonyl portion of an
amide group. In such an instance, the urea can be considered
functionally as an "amine-containing" functional group for the
purposes of the present invention herein, except in situations
where such inclusion is specifically contradicted. Aside from
ureas, other examples of such amine-containing functional groups
that may be suitable for satisfying the at least one amine group in
the first organic compound can generally include, but are not
limited to, hydrazides, sulfonamides, and the like, and
combinations thereof.
[0098] The amine functional group from the first organic compound
can include primary or secondary amines, as mentioned above, but
generally does not include quaternary amines, and in some instances
does not include tertiary amines either. Furthermore, the first
organic compound can optionally contain other functional groups
besides amines. For instance, the first organic compound can
comprise an aminoacid, which possesses an amine functional group
and a carboxylic acid functional group simultaneously. Aside from
carboxylic acids, other examples of such secondary functional
groups in amine-containing organic compounds can generally include,
but are not limited to, hydroxyls, aldehydes, anhydrides, ethers,
esters, imines, imides, ketones, thiols (mercaptans), thioesters,
and the like, and combinations thereof.
[0099] Additionally or alternately, in other aspects involving
formation of a condensation product (including aspects involving ex
situ formation of an amide), the amine functional group from the
first organic compound can include primary or secondary amines, as
mentioned above, but generally does not include tertiary or
quaternary amines, as tertiary and quaternary amines tend not to be
able to form amides. Furthermore, the first organic compound can
contain other functional groups besides amines, whether or not they
are capable of participating in forming an amide or other
condensation reaction product with one or more of the functional
groups from second organic compound. For instance, the first
organic compound can comprise an aminoacid, which possesses an
amine functional group and a carboxylic acid functional group
simultaneously. In such an instance, the aminoacid would qualify as
only one of the organic compounds, and not both; thus, in such an
instance, either an additional amine-containing (first) organic
compound would need to be present (in the circumstance where the
aminoacid would be considered the second organic compound) or an
additional carboxylic acid-containing (second) organic compound
would need to be present (in the circumstance where the aminoacid
would be considered the first organic compound). Aside from
carboxylic acids, other examples of such secondary functional
groups in amine-containing organic compounds can generally include,
but are not limited to, hydroxyls, aldehydes, anhydrides, ethers,
esters, imines, imides, ketones, thiols (mercaptans), thioesters,
and the like, and combinations thereof.
[0100] Additionally or alternately, the amine portion of the first
organic compound can be a part of a larger functional group in that
compound, so long as the amine portion (notably the amine nitrogen
and the constituents attached thereto) retains the capability of
participating in forming an amide or other condensation reaction
product with one or more of the functional groups from second
organic compound. For instance, the first organic compound can
comprise a urea, which functional group comprises an amine portion
attached to the carbonyl portion of an amide group. In such an
instance, provided the amine portion of the urea functional group
of the first organic compound would still be able to undergo a
condensation reaction with the carboxylic acid functional group of
the second organic compound, then the urea can be considered
functionally as an "amine-containing" functional group for the
purposes of the present invention herein, except in situations
where such inclusion is specifically contradicted. Aside from
ureas, other examples of such amine-containing functional groups
that may be suitable for satisfying the at least one amine group in
the first organic compound can generally include, but are not
limited to, hydrazides, sulfonamides, and the like, and
combinations thereof.
[0101] Representative examples of organic compounds containing
carboxylic acids can include, but are not limited to, primary
and/or secondary, linear, branched, and/or cyclic amines, such as
triacontanoic acid, octacosanoic acid, hexacosanoic acid,
tetracosanoic acid, docosanoic acid, erucic acid, docosahexanoic
acid, eicosanoic acid, eicosapentanoic acid, arachidonic acid,
octadecanoic acid, oleic acid, elaidic acid, stearidonic acid,
linoleic acid, alpha-linolenic acid, hexadecanoic acid, sapienic
acid, palmitoleic acid, tetradecanoic acid, myristoleic acid,
dodecanoic acid, decanoic acid, nonanoic acid, cyclooctanoic acid,
octanoic acid, cycloheptanoic acid, heptanoic acid, cyclohexanoic
acid, hexanoic acid, adamantanecarboxylic acid, norbornaneacetic
acid, benzoic acid, salicylic acid, acetylsalicylic acid, citric
acid, maleic acid, malonic acid, glutaric acid, lactic acid, oxalic
acid, tartaric acid, cinnamic acid, vanillic acid, succinic acid,
adipic acid, phthalic acid, isophthalic acid, terephthalic acid,
ethylenediaminetetracarboxylic acids (such as EDTA), fumaric acid,
alanine, arginine, aspartic acid, glutamic acid, glutamine,
glycine, histidine, isoleucine, leucine, lysine, phenylalanine,
serine, threonine, valine, 1,2-cyclohexanedicarboxylic acid,
1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid,
and the like, and combinations thereof. In an embodiment, the molar
ratio of the Group 6 metal(s) in the composition to the second
organic compound during treatment can be from about 3:1 to about
20:1.
[0102] In some aspects, the second organic compound can optionally
contain other functional groups besides carboxylic acids. For
instance, the second organic compound can comprise an aminoacid,
which possesses a carboxylic acid functional group and an amine
functional group simultaneously. Aside from amines, other examples
of such secondary functional groups in carboxylic acid-containing
organic compounds can generally include, but are not limited to,
hydroxyls, aldehydes, anhydrides, ethers, esters, imines, imides,
ketones, thiols (mercaptans), thioesters, and the like, and
combinations thereof. In some embodiments, the second organic
compound can contain no additional amine or alcohol functional
groups in addition to the carboxylic acid functional group(s).
[0103] Additionally or alternately, the reactive portion of the
second organic compound can be a part of a larger functional group
in that compound and/or can be a derivative of a carboxylic acid
that behaves similarly enough to a carboxylic acid, such that the
reactive portion and/or derivative retains its operability as a
Lewis acid. One example of a carboxylic acid derivative can include
an alkyl carboxylate ester, where the alkyl group does not
substantially hinder (over a reasonable time scale) the Lewis acid
functionality of the carboxylate portion of the functional
group.
[0104] In other aspects involving formation of a condensation
product (including aspects involving ex situ formation of an
amide), the second organic compound can contain other functional
groups besides carboxylic acids, whether or not they are capable of
participating in forming an amide or other condensation reaction
product with one or more of the functional groups from first
organic compound. For instance, the second organic compound can
comprise an aminoacid, which possesses a carboxylic acid functional
group and an amine functional group simultaneously. In such an
instance, the aminoacid would qualify as only one of the organic
compounds, and not both; thus, in such an instance, either an
additional amine-containing (first) organic compound would need to
be present (in the circumstance where the aminoacid would be
considered the second organic compound) or an additional carboxylic
acid-containing (second) organic compound would need to be present
(in the circumstance where the aminoacid would be considered the
first organic compound). Aside from amines, other examples of such
secondary functional groups in carboxylic acid-containing organic
compounds can generally include, but are not limited to, hydroxyls,
aldehydes, anhydrides, ethers, esters, imines, imides, ketones,
thiols (mercaptans), thioesters, and the like, and combinations
thereof.
[0105] Additionally or alternately, the reactive portion of the
second organic compound can be a part of a larger functional group
in that compound and/or can be a derivative of a carboxylic acid
that behaves similarly enough to a carboxylic acid in the presence
of the amine functional group of the first organic compound, such
that the reactive portion and/or derivative retains the capability
of participating in forming an amide or other desired condensation
reaction product with one or more of the functional groups from
first organic compound. One example of a carboxylic acid derivative
can include an alkyl carboxylate ester, where the alkyl group does
not substantially hinder (over a reasonable time scale) the
condensation reaction between the amine and the carboxylate portion
of the ester to form an amide.
[0106] For aspects involving formation of a condensation product
(including aspects involving ex situ formation of an amide), while
there is not a strict limit on the ratio between the first organic
compound and the second organic compound, because the goal of the
addition of the first and second organic compounds is to attain a
condensation reaction product, it may be desirable to have a ratio
of the reactive functional groups within the first and second
organic compounds, respectively, from about 1:4 to about 4:1, for
example from about 1:3 to about 3:1 or from about 1:2 to about
2:1.
[0107] In certain aspects, the organic compound(s)/additive(s)
and/or the reaction product(s) are not located/incorporated within
the crystal lattice of the mixed metal oxide precursor composition,
e.g., instead being located on the surface and/or within the pore
volume of the precursor composition and/or being associated with
(bound to) one or more metals or oxides of metals in a manner that
does not significantly affect the crystalline lattice of the mixed
metal oxide precursor composition, as observed through XRD and/or
other crystallographic spectra. It is noted that, in these certain
embodiments, a sulfided version of the mixed metal oxide precursor
composition can still have its sulfided form affected by the
organic compound(s)/additive(s) and/or the reaction product(s),
even though the oxide lattice is not significantly affected.
[0108] In some aspects, one way to attain a catalyst precursor
composition containing a decomposition/dehydrogenation reaction
product, such as one containing additional unsaturations, includes:
(a) treating a catalyst precursor composition, which comprises at
least one metal from Group 6 of the Periodic Table of the Elements
and at least one metal from Groups 8-10 of the Periodic Table of
the Elements, with a first organic compound containing at least one
amine group or a second organic compound separate from said first
organic compound and containing at least one carboxylic acid group,
but not both, to form an organically treated precursor catalyst
composition; and (b) heating the organically treated precursor
catalyst composition at a temperature sufficient and for a time
sufficient for the first or second organic compounds to react to
form an in situ product containing additional unsaturation (for
example, depending upon the nature of the first or second organic
compound, the temperature can be from about 195.degree. C. to about
260.degree. C., such as from about 200.degree. C. to about
250.degree. C.), thereby forming the additionally-unsaturated
and/or additionally oxidized catalyst precursor composition.
[0109] In certain advantageous embodiments, the heating step (b)
above can be conducted for a sufficiently long time so as to form
additional unsaturation(s), which may result from at least partial
decomposition (e.g., oxidative and/or non-oxidative dehydrogenation
and/or aromatization) of some (typically-unfunctionalized organic)
portions of the first or second organic compounds, but generally
not for so long that the at least partial decomposition volatilizes
more than 50% by weight of the first or second organic compounds.
Without being bound by theory, it is believed that additional
unsaturation(s) formed in situ and present at the point of
sulfiding the catalyst precursor composition to form a sulfided
(hydroprocessing) catalyst composition can somehow assist in
controlling one or more of the following: the size of sulfided
crystallites; the coordination of one or more of the metals during
sulfidation, such that a higher proportion of the one or more types
of metals are in appropriate sites for promoting desired
hydroprocessing reactions (such as hydrotreating,
hydrodenitrogenation, hydrodesulfurization, hydrodeoxygenation,
hydrodemetallation, hydrocracking including selective
hydrocracking, hydroisomerization, hydrodewaxing, and the like, and
combinations thereof, and/or for reducing/minimizing undesired
hydroprocessing reactions, such as aromatic saturation,
hydrogenation of double bonds, and the like, and combinations
thereof) than for sulfided catalysts made in the absence of the in
situ formed reaction product having additional unsaturation(s); and
coordination/catalysis involving one or more of the metals after
sulfidation, such that a higher proportion (or each) of the one or
more types of metals are more efficient at promoting desired
hydroprocessing reactions (e.g., because the higher proportion of
metal sites can catalyze more hydrodesulfurization reactions of the
same type in a given timescale and/or because the higher proportion
of the metal sites can catalyze more difficult hydrodesulfurization
reactions in a similar timescale) than for sulfided catalysts made
in the absence of the in situ formed reaction product having
additional unsaturation(s).
[0110] In other aspects, one way to attain a catalyst precursor
composition containing a condensation reaction product, such as an
amide, and/or a reaction product containing additional
unsaturations includes: (a) treating a catalyst precursor
composition, which comprises at least one metal from Group 6 of the
Periodic Table of the Elements and at least one metal from Groups
8-10 of the Periodic Table of the Elements, with a first organic
compound containing at least one amine group and a second organic
compound separate from said first organic compound and containing
at least one carboxylic acid group to form an organically treated
precursor catalyst composition; and (b) heating the organically
treated precursor catalyst composition at a temperature sufficient
and for a time sufficient for the first and second organic
compounds to react to form an in situ condensation product and/or
an in situ product containing additional unsaturation (for amides
made from amines and carboxylic acids, for example, the temperature
can be from about 195.degree. C. to about 260.degree. C., such as
from about 200.degree. C. to about 250.degree. C.), thereby forming
the amide-containing and/or additionally-unsaturated and/or
additionally oxidized catalyst precursor composition.
[0111] Practically, the treating step (a) above can comprise one
(or more) of three methods: (1) first treating the catalyst
precursor composition with the first organic compound and second
with the second organic compound; (2) first treating the catalyst
precursor composition with the second organic compound and second
with the first organic compound; and/or (3) treating the catalyst
precursor composition simultaneously with the first organic
compound and with the second organic compound.
[0112] In certain advantageous embodiments, the heating step (b)
above can be conducted for a sufficiently long time so as to form
the amide, but not for so long that the amide so formed
substantially decomposes. Additionally or alternately in such
advantageous embodiments, the heating step (b) above can be
conducted for a sufficiently long time so as to form additional
unsaturation(s), which may result from at least partial
decomposition (e.g., oxidative and/or non-oxidative dehydrogenation
and/or aromatization) of some (typically-unfunctionalized organic)
portions of the organic compounds, but generally not for so long
that the at least partial decomposition (i) substantially
decomposes any condensation product, such as amide, and/or (ii)
volatilizes more than 50% by weight of the combined first and
second organic compounds. Without being bound by theory, it is
believed that in situ formed amide and/or additional
unsaturation(s) present at the point of sulfiding the catalyst
precursor composition to form a sulfided (hydroprocessing) catalyst
composition can somehow assist in controlling one or more of the
following: the size of sulfided crystallites; the coordination of
one or more of the metals during sulfidation, such that a higher
proportion of the one or more types of metals are in appropriate
sites for promoting desired hydroprocessing reactions (such as
hydrotreating, hydrodenitrogenation, hydrodesulfurization,
hydrodeoxygenation, hydrodemetallation, hydrocracking including
selective hydrocracking, hydroisomerization, hydrodewaxing, and the
like, and combinations thereof, and/or for reducing/minimizing
undesired hydroprocessing reactions, such as aromatic saturation,
hydrogenation of double bonds, and the like, and combinations
thereof) than for sulfided catalysts made in the absence of the in
situ formed reaction product having an amide (condensation reaction
product of functional groups) and/or additional unsaturation(s);
and coordination/catalysis involving one or more of the metals
after sulfidation, such that a higher proportion (or each) of the
one or more types of metals are more efficient at promoting desired
hydroprocessing reactions (e.g., because the higher proportion of
metal sites can catalyze more hydrodesulfurization reactions of the
same type in a given timescale and/or because the higher proportion
of the metal sites can catalyze more difficult hydrodesulfurization
reactions in a similar timescale) than for sulfided catalysts made
in the absence of the in situ formed reaction product having an
amide (condensation reaction product of functional groups) and/or
additional unsaturation(s).
[0113] When used to make a bulk mixed metal catalyst precursor
composition, the in situ reacted catalyst precursor composition
can, in one embodiment, consist essentially of the reaction
product, an oxide form of the at least one metal from Group 6, an
oxide form of the at least one metal from Groups 8-10, and
optionally about 20 wt % or less of a binder (e.g., about 10 wt %
or less).
[0114] After treatment of the catalyst precursor containing the at
least one Group 6 metal and the at least one Group 8-10 metal with
the first and/or second organic compounds, the organically treated
catalyst precursor composition can be heated to a temperature high
enough to form the reaction product and optionally but preferably
high enough to enable any
dehydrogenation/decomposition/condensation byproduct to be easily
removed (e.g., in order to drive the reaction equilibrium to the at
least partially dehydrogenated/decomposed product and/or
condensation product). Additionally or alternately, the organically
treated catalyst precursor composition can be heated to a
temperature low enough so as to substantially retain the reaction
product containing the additional unsaturations and/or the
condensation product, so as not to significantly decompose the
reaction product, and/or so as not to significantly volatilize
(more than 50% by weight of) the first and/or second organic
compounds (whether reacted or not).
[0115] It is contemplated that the specific lower and upper
temperature limits based on the above considerations can be highly
dependent upon a variety of factors that can include, but are not
limited to, the atmosphere under which the heating is conducted,
the chemical and/or physical properties of the first organic
compound, the second organic compound, the reaction product, and/or
any reaction byproduct, or a combination thereof. In one
embodiment, the heating temperature can be at least about
120.degree. C., for example at least about 150.degree. C., at least
about 165.degree. C., at least about 175.degree. C., at least about
185.degree. C., at least about 195.degree. C., at least about
200.degree. C., at least about 210.degree. C., at least about
220.degree. C., at least about 230.degree. C., at least about
240.degree. C., or at least about 250.degree. C. Additionally or
alternately, the heating temperature can be not greater than about
400.degree. C., for example not greater than about 375.degree. C.,
not greater than about 350.degree. C., not greater than about
325.degree. C., not greater than about 300.degree. C., not greater
than about 275.degree. C., not greater than about 250.degree. C.,
not greater than about 240.degree. C., not greater than about
230.degree. C., not greater than about 220.degree. C., not greater
than about 210.degree. C., or not greater than about 200.degree.
C.
[0116] In one embodiment, the heating can be conducted in a low- or
non-oxidizing atmosphere (and conveniently in an inert atmosphere,
such as nitrogen). In an alternate embodiment, the heating can be
conducted in a moderately- or highly-oxidizing environment. In
another alternate embodiment, the heating can include a multi-step
process in which one or more heating steps can be conducted in the
low- or non-oxidizing atmosphere, in which one or more heating
steps can be conducted in the moderately- or highly-oxidizing
environment, or both. Of course, the period of time for the heating
in the environment can be tailored to the first or second organic
compound, but can typically extend from about 5 minutes to about
168 hours, for example from about 10 minutes to about 96 hours,
from about 10 minutes to about 48 hours, from about 10 minutes to
about 24 hours, from about 10 minutes to about 18 hours, from about
10 minutes to about 12 hours, from about 10 minutes to about 8
hours, from about 10 minutes to about 6 hours, from about 10
minutes to about 4 hours, from about 20 minutes to about 96 hours,
from about 20 minutes to about 48 hours, from about 20 minutes to
about 24 hours, from about 20 minutes to about 18 hours, from about
20 minutes to about 12 hours, from about 20 minutes to about 8
hours, from about 20 minutes to about 6 hours, from about 20
minutes to about 4 hours, from about 30 minutes to about 96 hours,
from about 30 minutes to about 48 hours, from about 30 minutes to
about 24 hours, from about 30 minutes to about 18 hours, from about
30 minutes to about 12 hours, from about 30 minutes to about 8
hours, from about 30 minutes to about 6 hours, from about 30
minutes to about 4 hours, from about 45 minutes to about 96 hours,
from about 45 minutes to about 48 hours, from about 45 minutes to
about 24 hours, from about 45 minutes to about 18 hours, from about
45 minutes to about 12 hours, from about 45 minutes to about 8
hours, from about 45 minutes to about 6 hours, from about 45
minutes to about 4 hours, from about 1 hour to about 96 hours, from
about 1 hour to about 48 hours, from about 1 hour to about 24
hours, from about 1 hour to about 18 hours, from about 1 hour to
about 12 hours, from about 1 hour to about 8 hours, from 1 hour
minutes to about 6 hours, or from about 1 hour to about 4
hours.
[0117] Additionally or alternately, in aspects where an ex situ
formed amide is used, the amide can be formed prior to impregnation
into the metal oxide component of the catalyst precursor by
reaction of the amine component and the carboxylic acid component.
Reaction typically takes place readily at mildly elevated
temperatures up to about 200.degree. C. with liberation of water as
a by-product of the reaction at temperatures above 100.degree. C.
and usually above 150.degree. C. The reactants can usually be
heated together to form a melt in which the reaction takes place
and the melt impregnated directly into the metal oxide component
which is preferably pre-heated to the same temperature as the melt
in order to assist penetration into the structure of the metal
oxide component. The reaction can also be carried out in the
presence of a solvent if desired and the resulting solution used
for the impregnation step. In certain embodiments, the amide and
its heat treated derivative may not be located/incorporated within
the crystal lattice of the mixed metal oxide precursor, e.g., may
instead be located on the surface and/or within the pore volume of
the precursor and/or be associated with (bound to) one or more
metals or oxides of metals in a manner that does not significantly
affect the crystalline lattice of the mixed metal oxide precursor
composition, as observed through XRD and/or other crystallographic
spectra. A sulfided version of the mixed metal oxide precursor
composition can still have its sulfided form affected by the
organic compound(s)/additive(s) and/or the reaction product(s),
even though the oxide lattice is not significantly affected.
[0118] There is not a strict limit on the ratio between the amine
reactant and the carboxylic reactant, and accordingly, the ratio of
the reactive amine and carboxylic acid groups in the two reactants
may vary, respectively, from about 1:4 to about 4:1, for example
from about 1:3 to about 3:1 or from about 1:2 to about 2:1. It has
been observed that catalysts made with amides from equimolar
quantities of the amine and carboxylic acid reactants compounds
show performance improvements in hydroprocessing certain feeds and
for this reason, amides made with an equimolar ratio are
preferred.
[0119] The pre-formed amide is suitably impregnated into the metal
oxide precursor by incipient wetness impregnation with the amount
determined according to the pore volume of the metal oxide
component. Following impregnation, a heat treatment is carried out
which first removes any residual water and/or solvent but also
creates a reaction product containing additional unsaturation sites
and possibly additional oxygen. The amide-impregnated metal oxide
component is then heated at a temperature sufficient and for a time
sufficient to form a product containing the additional unsaturation
which is characteristic of the desired organic component; this
treatment with the pre-formed amide is typically from about
195.degree. C. to about 280.degree. C., for example from about
200.degree. C. to about 250.degree. C.).
[0120] The heating step should not be conducted for so long that
the amide becomes substantially decomposed but is continued for a
sufficiently long time to form additional unsaturation(s), which
may result from at least partial decomposition (e.g., oxidative
and/or non-oxidative dehydrogenation and/or aromatization) of some
(typically-unfunctionalized organic) portions of the organic
compounds. On the other hand, the heating should not be conducted
for so long that the decomposition substantially results in gross
decomposition of the amide or any condensation product. The
impregnated catalyst precursor composition can be heated to a
temperature high enough to form the unsaturated reaction product
and typically high enough to enable any byproducts such as water to
be removed. The temperature to which the impregnated precursor
composition is heated should, however, maintained low enough so as
to substantially retain the amide reaction product with the
additional unsaturations and any oxygen, and so as not to
significantly decompose the functionalized reaction product, and/or
so as not to significantly volatilize (more than 50% by weight of)
the amide.
[0121] The specific lower and upper temperature limits based on the
above considerations can be dependent upon a variety of factors
that can include, but are not limited to, the atmosphere under
which the heating is conducted, the chemical and/or physical
properties of the amide, the amide reaction product, and/or any
functionalized reaction byproduct as well as the desired duration
of the heating with higher temperatures, e.g. over the optimal
temperature range up to 250.degree. C., enabling shorter heating
durations to be utilized. The minimum heating temperature can, for
example, suitably be at least about 120.degree. C., for example at
least about 150.degree. C., at least about 165.degree. C., at least
about 175.degree. C., at least about 185.degree. C., at least about
195.degree. C., at least about 200.degree. C., at least about
210.degree. C., at least about 220.degree. C., at least about
230.degree. C., at least about 240.degree. C., or at least about
250.degree. C. The maximum heating temperature should not be
greater than about 400.degree. C., for example, not greater than
about 375.degree. C., not greater than about 350.degree. C., not
greater than about 325.degree. C., not greater than about
300.degree. C., not greater than about 275.degree. C., not greater
than about 250.degree. C., not greater than about 240.degree. C.,
not greater than about 230.degree. C., not greater than about
220.degree. C., not greater than about 210.degree. C., or not
greater than about 200.degree. C. Resort to temperatures above the
preferred maximum of 250.degree. C. should be made with due care to
avoid the gross decomposition of the amide as noted above but a
slightly higher range, for example, 250-280.degree. C., e.g. 260 or
275.degree. C. may permit usefully shorter heating steps in
commercial scale operation. The temperature to be used should
therefore be selected on an empirical basis depending on the nature
of the amide used in the impregnation. The progress of the heating
can be monitored according to the properties of the treated
product, including analysis by GC-MS and by its infrared spectrum
as described below.
[0122] In an embodiment, the organically treated catalyst precursor
composition and/or the catalyst precursor composition containing
the reaction product can contain from about 4 wt % to about 20 wt
%, for example from about 5 wt % to about 15 wt %, carbon resulting
from the first and second organic compounds and/or from the
condensation product, as applicable, based on the total weight of
the relevant composition.
[0123] Additionally or alternately, as a result of the heating
step, the reaction product from the organically treated catalyst
precursor can exhibit a content of unsaturated carbon atoms (which
includes aromatic carbon atoms), as measured according to peak area
comparisons using .sup.13C NMR techniques, of at least 29%, for
example at least about 30%, at least about 31%, at least about 32%,
or at least about 33%. Further additionally or alternately, the
reaction product from the organically treated catalyst precursor
can optionally exhibit a content of unsaturated carbon atoms (which
includes aromatic carbon atoms), as measured according to peak area
comparisons using .sup.13C NMR techniques, of up to about 70%, for
example up to about 65%, up to about 60%, up to about 55%, up to
about 50%, up to about 45%, up to about 40%, or up to about 35%.
Still further additionally or alternately, as a result of the
heating step, the reaction product from the organically treated
catalyst precursor can exhibit an increase in content of
unsaturated carbon atoms (which includes aromatic carbon atoms), as
measured according to peak area comparisons using .sup.13C NMR
techniques, of at least about 17%, for example at least about 18%,
at least about 19%, at least about 20%, or at least about 21%
(e.g., in an embodiment where the first organic compound is
oleylamine and the second organic compound is oleic acid, such that
the combined unsaturation level of the unreacted compounds is about
11.1% of carbon atoms, an about 17% increase in unsaturated carbons
upon heating corresponds to about 28.1% content of unsaturated
carbon atoms in the reaction product). Yet further additionally or
alternately, the reaction product from the organically treated
catalyst precursor can optionally exhibit an increase in content of
unsaturated carbon atoms (which includes aromatic carbon atoms), as
measured according to peak area comparisons using .sup.13C NMR
techniques, of up to about 60%, for example up to about 55%, up to
about 50%, up to about 45%, up to about 40%, up to about 35%, up to
about 30%, or up to about 25%.
[0124] Again further additionally or alternately, as a result of
the heating step, the reaction product from the organically treated
catalyst precursor can exhibit a ratio of unsaturated carbon atoms
to aromatic carbon atoms, as measured according to peak area ratios
using infrared spectroscopic techniques of a deconvoluted peak
centered from about 1700 cm.sup.-1 to about 1730 cm.sup.-1 (e.g.,
at about 1715 cm.sup.-1), compared to a deconvoluted peak centered
from about 1380 cm.sup.-1 to about 1450 cm.sup.-1 (e.g., from about
1395 cm.sup.-1 to about 1415 cm.sup.-1), of at least 0.9, for
example at least 1.0, at least 1.1, at least 1.2, at least 1.3, at
least 1.4, at least 1.5, at least 1.7, at least 2.0, at least 2.2,
at least 2.5, at least 2.7, or at least 3.0. Again still further
additionally or alternately, the reaction product from the
organically treated catalyst precursor can exhibit a ratio of
unsaturated carbon atoms to aromatic carbon atoms, as measured
according to peak area ratios using infrared spectroscopic
techniques of a deconvoluted peak centered from about 1700
cm.sup.-1 to about 1730 cm.sup.-1 (e.g., at about 1715 cm.sup.-1),
compared to a deconvoluted peak centered from about 1380 cm.sup.-1
to about 1450 cm.sup.-1 (e.g., from about 1395 cm.sup.-1 to about
1415 cm.sup.-1), of up to 15, for example up to 10, up to 8.0, up
to 7.0, up to 6.0, up to 5.0, up to 4.5, up to 4.0, up to 3.5, or
up to 3.0.
[0125] A (sulfided) hydroprocessing catalyst composition can then
be produced by sulfiding the catalyst precursor composition
containing the reaction product. Sulfiding is generally carried out
by contacting the catalyst precursor composition containing the
reaction product with a sulfur-containing compound (e.g., elemental
sulfur, hydrogen sulfide, polysulfides, or the like, or a
combination thereof, which may originate from a fossil/mineral oil
stream, from a biocomponent-based oil stream, from a combination
thereof, or from a sulfur-containing stream separate from the
aforementioned oil stream(s)) at a temperature and for a time
sufficient to substantially sulfide the composition and/or
sufficient to render the sulfided composition active as a
hydroprocessing catalyst. For instance, the sulfidation can be
carried out at a temperature from about 300.degree. C. to about
400.degree. C., e.g., from about 310.degree. C. to about
350.degree. C., for a period of time from about 30 minutes to about
96 hours, e.g., from about 1 hour to about 48 hours or from about 4
hours to about 24 hours. The sulfiding can generally be conducted
before or after combining the metal (oxide) containing composition
with a binder, if desired, and before or after forming the
composition into a shaped catalyst. The sulfiding can additionally
or alternately be conducted in situ in a hydroprocessing reactor.
Obviously, to the extent that a reaction product of the first or
second organic compounds contains additional unsaturations formed
in situ, it would generally be desirable for the sulfidation
(and/or any catalyst treatment after the organic treatment) to
significantly maintain the in situ formed additional unsaturations
of said reaction product.
[0126] The sulfided catalyst composition can exhibit a layered
structure comprising a plurality of stacked YS.sub.2 layers, where
Y is the Group 6 metal(s), such that the average number of stacks
(typically for bulk organically treated catalysts) can be from
about 1.5 to about 3.5, for example from about 1.5 to about 3.0,
from about 2.0 to about 3.3, from about 2.0 to about 3.0, or from
about 2.1 to about 2.8. For instance, the treatment of the metal
(oxide) containing precursor composition according to the invention
can afford a decrease in the average number of stacks of the
treated precursor of at least about 0.8, for example at least about
1.0, at least about 1.2, at least about 1.3, at least about 1.4, or
at least about 1.5, as compared to an untreated metal (oxide)
containing precursor composition. As such, the number of stacks can
be considerably less than that obtained with an equivalent sulfided
mixed metal (oxide) containing precursor composition produced
without the first or second organic compound treatment. The
reduction in the average number of stacks can be evidenced, e.g.,
via X-ray diffraction spectra of relevant sulfided compositions, in
which the (002) peak appears significantly broader (as determined
by the same width at the half-height of the peak) than the
corresponding peak in the spectrum of the sulfided mixed metal
(oxide) containing precursor composition produced without the
organic treatment (and/or, in certain cases, with only a single
organic compound treatment using an organic compound having less
than 10 carbon atoms) according to the present invention.
Additionally or alternately to X-ray diffraction, transmission
electron microscopy (TEM) can be used to obtain micrographs of
relevant sulfided compositions, including multiple microcrystals,
within which micrograph images the multiple microcrystals can be
visually analyzed for the number of stacks in each, which can then
be averaged over the micrograph visual field to obtain an average
number of stacks that can evidence a reduction in average number of
stacks compared to a sulfided mixed metal (oxide) containing
precursor composition produced without the organic treatment
(and/or, in certain cases, with only a single organic compound
treatment) according to the present invention.
[0127] The sulfided catalyst composition described above can be
used as a hydroprocessing catalyst, either alone or in combination
with a binder. If the sulfided catalyst composition is a bulk
catalyst, then only a relatively small amount of binder may be
added. However, if the sulfided catalyst composition is a
heterogeneous/supported catalyst, then usually the binder is a
significant portion of the catalyst composition, e.g., at least
about 40 wt %, at least about 50 wt %, at least about 60 wt %, or
at least about 70 wt %; additionally or alternately for
heterogeneous/supported catalysts, the binder can comprise up to
about 95 wt % of the catalyst composition, e.g., up to about 90 wt
%, up to about 85 wt %, up to about 80 wt %, up to about 75 wt %,
or up to about 70 wt %. Non-limiting examples of suitable binder
materials can include, but are not limited to, silica,
silica-alumina (e.g., conventional silica-alumina, silica-coated
alumina, alumina-coated silica, or the like, or a combination
thereof), alumina (e.g., boehmite, pseudo-boehmite, gibbsite, or
the like, or a combination thereof), titania, zirconia, cationic
clays or anionic clays (e.g., saponite, bentonite, kaoline,
sepiolite, hydrotalcite, or the like, or a combination thereof),
and mixtures thereof. In some preferred embodiments, the binder can
include silica, silica-alumina, alumina, titania, zirconia, and
mixtures thereof. These binders may be applied as such or after
peptization. It may also be possible to apply precursors of these
binders that, during precursor synthesis, can be converted into any
of the above-described binders. Suitable precursors can include,
e.g., alkali metal aluminates (alumina binder), water glass (silica
binder), a mixture of alkali metal aluminates and water glass
(silica-alumina binder), a mixture of sources of a di-, tri-,
and/or tetravalent metal, such as a mixture of water-soluble salts
of magnesium, aluminum, and/or silicon (cationic clay and/or
anionic clay), chlorohydrol, aluminum sulfate, or mixtures
thereof.
[0128] Generally, the binder material to be used can have lower
catalytic activity than the remainder of the catalyst composition,
or can have substantially no catalytic activity at all (less than
about 5%, based on the catalytic activity of the bulk catalyst
composition being about 100%). Consequently, by using a binder
material, the activity of the catalyst composition may be reduced.
Therefore, the amount of binder material to be used, at least in
bulk catalysts, can generally depend on the desired activity of the
final catalyst composition. Binder amounts up to about 25 wt % of
the total composition can be suitable (when present, from above 0
wt % to about 25 wt %), depending on the envisaged catalytic
application. However, to take advantage of the resulting unusual
high activity of bulk catalyst compositions according to the
invention, binder amounts, when added, can generally be from about
0.5 wt % to about 20 wt % of the total catalyst composition.
[0129] If desired in bulk catalyst cases, the binder material can
be composited with a source of a Group 6 metal and/or a source of a
non-noble Group 8-10 metal, prior to being composited with the bulk
catalyst composition and/or prior to being added during the
preparation thereof. Compositing the binder material with any of
these metals may be carried out by any known means, e.g.,
impregnation of the (solid) binder material with these metal(s)
sources.
[0130] A cracking component may also be added during catalyst
preparation. When used, the cracking component can represent from
about 0.5 wt % to about 30 wt %, based on the total weight of the
catalyst composition. The cracking component may serve, for
example, as an isomerization enhancer. Conventional cracking
components can be used, e.g., a cationic clay, an anionic clay, a
zeolite (such as ZSM-5, zeolite Y, ultra-stable zeolite Y, zeolite
X, an AlPO, a SAPO, or the like, or a combination thereof),
amorphous cracking components (such as silica-alumina or the like),
or a combination thereof. It is to be understood that some
materials may act as a binder and a cracking component at the same
time. For instance, silica-alumina may simultaneously have both a
cracking and a binding function.
[0131] If desired, the cracking component may be composited with a
Group 6 metal and/or a Group 8-10 non-noble metal, prior to being
composited with the catalyst composition and/or prior to being
added during the preparation thereof. Compositing the cracking
component with any of these metals may be carried out by any known
means, e.g., impregnation of the cracking component with these
metal(s) sources. When both a cracking component and a binder
material are used and when compositing of additional metal
components is desired on both, the compositing may be done on each
component separately or may be accomplished by combining the
components and doing a single compositing step.
[0132] The selection of particular cracking components, if any, can
depend on the intended catalytic application of the final catalyst
composition. For instance, a zeolite can be added if the resulting
composition is to be applied in hydrocracking or fluid catalytic
cracking. Other cracking components, such as silica-alumina or
cationic clays, can be added if the final catalyst composition is
to be used in hydrotreating applications. The amount of added
cracking material can depend on the desired activity of the final
composition and the intended application, and thus, when present,
may vary from above 0 wt % to about 80 wt %, based on the total
weight of the catalyst composition. In a preferred embodiment, the
combination of cracking component and binder material can comprise
less than 50 wt % of the catalyst composition, for example, less
than about 40 wt %, less than about 30 wt %, less than about 20 wt
%, less than about 15 wt %, or less than about 10 wt %.
[0133] If desired, further materials can be added, in addition to
the metal components already added, such as any material that would
be added during conventional hydroprocessing catalyst preparation.
Suitable examples of such further materials can include, but are
not limited to, phosphorus compounds, boron compounds,
fluorine-containing compounds, sources of additional transition
metals, sources of rare earth metals, fillers, or mixtures
thereof.
Additional Embodiments
Embodiment 1
[0134] A hydrotreatment process comprising: reacting a feedstream,
the feedstream having a sulfur content of about 500 wppm to about
50000 wppm and an aromatics content of at least about 60 wt %, or
at least about 70 wt %, in the presence of a hydrogen-containing
treat gas and in the presence of a mixed metal catalyst under
effective hydrotreating conditions for converting about 5 wt % or
less of the feedstream relative to a conversion temperature of
350.degree. F. (177.degree. C.); and separating the first liquid
effluent to produce a vapor phase stream and a liquid product
stream, the liquid product stream having a sulfur content of about
500 wppm or less, wherein the mixed metal catalyst comprises a
sulfided mixed metal catalyst formed by sulfiding a mixed metal
catalyst precursor composition, the mixed metal catalyst precursor
composition being produced by a) heating a composition comprising
at least one metal from Group 6 of the Periodic Table of the
Elements, at least one metal from Groups 8-10 of the Periodic Table
of the Elements, and a reaction product formed from (i) a first
organic compound containing at least one amine group, and (ii) a
second organic compound separate from said first organic compound
and containing at least one carboxylic acid group to a temperature
from about 195.degree. C. to about 260.degree. C. for a time
sufficient for the first and second organic compounds to form a
reaction product in situ that contains an amide moiety, unsaturated
carbon atoms not present in the first or second organic compounds,
oxygen atoms not present in the first or second organic compounds,
or a combination thereof; b) heating a composition comprising one
metal from Group 6 of the Periodic Table of the Elements, at least
one metal from Groups 8-10 of the Periodic Table of the Elements,
and a reaction product formed from (iii) a first organic compound
containing at least one amine group and at least 10 carbon atoms or
(iv) a second organic compound containing at least one carboxylic
acid group and at least 10 carbon atoms, but not both (iii) and
(iv), wherein the reaction product contains additional unsaturated
carbon atoms, relative to (iii) the first organic compound or (iv)
the second organic compound, wherein the metals of the catalyst
precursor composition are arranged in a crystal lattice, and
wherein the reaction product is not located within the crystal
lattice, to a temperature from about 195.degree. C. to about
260.degree. C. for a time sufficient for the first or second
organic compounds to form a reaction product in situ that contains
unsaturated carbon atoms not present in the first or second organic
compounds, oxygen atoms not present in the first or second organic
compounds, or a combination thereof; or c) heating a composition
comprising at least one metal from Group 6 of the Periodic Table of
the Elements, at least one metal from Groups 8-10 of the Periodic
Table of the Elements, and a pre-formed amide formed from (v) a
first organic compound containing at least one amine group, and
(vi) a second organic compound separate from said first organic
compound and containing at least one carboxylic acid group, to form
at least one of additional in situ unsaturated carbon atoms or in
situ added oxygen atoms not present in the first organic compound,
the second organic compound, or both, but not for so long that the
pre-formed amide substantially decomposes, thereby forming a
catalyst precursor containing at least one of in situ formed
unsaturated carbon atoms or in situ added oxygen atoms.
Embodiment 2
[0135] The process of Embodiment 1, wherein reacting the feedstream
in the presence of a mixed metal catalyst further comprises
reacting the feedstream in the presence of one or more additional
hydrotreating catalysts, the one or more additional hydrotreating
catalysts and the mixed metal catalyst optionally comprising a
catalyst mixture, or the one or more additional hydrotreating
catalysts and the mixed metal catalyst optionally comprising a
stacked bed of catalysts, or the one or more additional
hydrotreating catalysts and the mixed metal catalyst optionally
being located in separate catalyst beds, or a combination
thereof.
Embodiment 3
[0136] The process of Embodiments 1 or 2, wherein the effective
hydrotreating conditions comprise temperatures of about 200.degree.
C. to about 450.degree. C.; pressures of about 250 psig (1.8 MPag)
to about 5000 psig (34.6 MPag); liquid hourly space velocities
(LHSV) of about 0.1 hr.sup.-1 to about 10 hr.sup.-1; and hydrogen
treat rates of about 200 scf/B (35.6 m.sup.3/m.sup.3) to about
10,000 scf/B (1781 m.sup.3/m.sup.3).
Embodiment 4
[0137] A multistage hydroprocessing process comprising: reacting a
feedstream having a sulfur content of at least about 3000 wppm in a
first hydroprocessing stage in the presence of a
hydrogen-containing treat gas and in the presence of at least one
first stage hydroprocessing catalyst, the first hydroprocessing
stage being operated at first stage hydroprocessing conditions,
thereby resulting in a first liquid effluent having a sulfur
content of about 3000 wppm or less; separating at least a portion
of the first liquid effluent to produce a first vapor phase stream
and a first liquid product stream; reacting at least a portion of
the first liquid product stream in a second hydroprocessing stage
in the presence of a hydrogen-containing treat gas and a mixed
metal catalyst, the second hydroprocessing stage being operated at
second stage hydroprocessing conditions to produce a second liquid
effluent; and separating at least a portion of the second liquid
effluent to produce a second vapor phase stream and a second liquid
product stream having a sulfur content of about 500 wppm or less,
wherein the mixed metal catalyst comprises a sulfided mixed metal
catalyst formed by sulfiding a mixed metal catalyst precursor
composition, the mixed metal catalyst precursor composition being
produced by a) heating a composition comprising at least one metal
from Group 6 of the Periodic Table of the Elements, at least one
metal from Groups 8-10 of the Periodic Table of the Elements, and a
reaction product formed from (i) a first organic compound
containing at least one amine group, and (ii) a second organic
compound separate from said first organic compound and containing
at least one carboxylic acid group to a temperature from about
195.degree. C. to about 260.degree. C. for a time sufficient for
the first and second organic compounds to form a reaction product
in situ that contains an amide moiety, unsaturated carbon atoms not
present in the first or second organic compounds, oxygen atoms not
present in the first or second organic compounds, or a combination
thereof; b) heating a composition comprising one metal from Group 6
of the Periodic Table of the Elements, at least one metal from
Groups 8-10 of the Periodic Table of the Elements, and a reaction
product formed from (iii) a first organic compound containing at
least one amine group and at least 10 carbon atoms or (iv) a second
organic compound containing at least one carboxylic acid group and
at least 10 carbon atoms, but not both (iii) and (iv), wherein the
reaction product contains additional unsaturated carbon atoms,
relative to (iii) the first organic compound or (iv) the second
organic compound, wherein the metals of the catalyst precursor
composition are arranged in a crystal lattice, and wherein the
reaction product is not located within the crystal lattice, to a
temperature from about 195.degree. C. to about 260.degree. C. for a
time sufficient for the first or second organic compounds to form a
reaction product in situ that contains unsaturated carbon atoms not
present in the first or second organic compounds, oxygen atoms not
present in the first or second organic compounds, or a combination
thereof; or c) heating a composition comprising at least one metal
from Group 6 of the Periodic Table of the Elements, at least one
metal from Groups 8-10 of the Periodic Table of the Elements, and a
pre-formed amide formed from (v) a first organic compound
containing at least one amine group, and (vi) a second organic
compound separate from said first organic compound and containing
at least one carboxylic acid group, to form at least one of
additional in situ unsaturated carbon atoms or in situ added oxygen
atoms not present in the first organic compound, the second organic
compound, or both, but not for so long that the pre-formed amide
substantially decomposes, thereby forming a catalyst precursor
containing at least one of in situ formed unsaturated carbon atoms
or in situ added oxygen atoms.
Embodiment 5
[0138] The process of Embodiment 4, wherein the first liquid
effluent has a sulfur content of at least about 1000 wppm, or at
least about 1500 wppm, or at least about 2000 wppm.
Embodiment 6
[0139] A multistage hydroprocessing process comprising: reacting a
feedstream in a first hydroprocessing stage in the presence of a
hydrogen-containing treat gas, the first stage containing one or
more reaction zones, each reaction zone operated at first stage
hydroprocessing conditions and in the presence of a first
hydroprocessing catalyst, thereby resulting in a first liquid
effluent; separating at least a portion of the first liquid
effluent to produce a first vapor phase stream and a first liquid
product stream, the first liquid product stream having a sulfur
content of about 1000 wppm to about 5000 wppm; reacting at least a
portion of the first liquid product stream in a second
hydroprocessing stage in the presence of a hydrogen-containing
treat gas, the second hydroprocessing stage containing at least one
reaction zone operated at second stage hydroprocessing conditions,
the at least one reaction zone containing a mixed metal
hydroprocessing catalyst, thereby resulting in a second liquid
effluent; and separating at least a portion of the second liquid
effluent to produce a second vapor phase stream and a second liquid
product stream, the second liquid product stream having a sulfur
content of about 100 wppm or less; wherein the mixed metal catalyst
comprises a sulfided mixed metal catalyst formed by sulfiding a
mixed metal catalyst precursor composition, the mixed metal
catalyst precursor composition being produced by a) heating a
composition comprising at least one metal from Group 6 of the
Periodic Table of the Elements, at least one metal from Groups 8-10
of the Periodic Table of the Elements, and a reaction product
formed from (i) a first organic compound containing at least one
amine group, and (ii) a second organic compound separate from said
first organic compound and containing at least one carboxylic acid
group to a temperature from about 195.degree. C. to about
260.degree. C. for a time sufficient for the first and second
organic compounds to form a reaction product in situ that contains
an amide moiety, unsaturated carbon atoms not present in the first
or second organic compounds, oxygen atoms not present in the first
or second organic compounds, or a combination thereof; b) heating a
composition comprising one metal from Group 6 of the Periodic Table
of the Elements, at least one metal from Groups 8-10 of the
Periodic Table of the Elements, and a reaction product formed from
(iii) a first organic compound containing at least one amine group
and at least 10 carbon atoms or (iv) a second organic compound
containing at least one carboxylic acid group and at least 10
carbon atoms, but not both (iii) and (iv), wherein the reaction
product contains additional unsaturated carbon atoms, relative to
(iii) the first organic compound or (iv) the second organic
compound, wherein the metals of the catalyst precursor composition
are arranged in a crystal lattice, and wherein the reaction product
is not located within the crystal lattice, to a temperature from
about 195.degree. C. to about 260.degree. C. for a time sufficient
for the first or second organic compounds to form a reaction
product in situ that contains unsaturated carbon atoms not present
in the first or second organic compounds, oxygen atoms not present
in the first or second organic compounds, or a combination thereof;
or c) heating a composition comprising at least one metal from
Group 6 of the Periodic Table of the Elements, at least one metal
from Groups 8-10 of the Periodic Table of the Elements, and a
pre-formed amide formed from (v) a first organic compound
containing at least one amine group, and (vi) a second organic
compound separate from said first organic compound and containing
at least one carboxylic acid group, to form at least one of
additional in situ unsaturated carbon atoms or in situ added oxygen
atoms not present in the first organic compound, the second organic
compound, or both, but not for so long that the pre-formed amide
substantially decomposes, thereby forming a catalyst precursor
containing at least one of in situ formed unsaturated carbon atoms
or in situ added oxygen atoms.
Embodiment 7
[0140] The process of any of Embodiments 4 to 6, further comprising
hydroprocessing at least a portion of the first liquid product
stream in an intermediate hydrotreating stage.
Embodiment 8
[0141] The process of any of Embodiments 4 to 7, wherein the
feedstream has an aromatics content of at least about 60 wt %, or
at least about 70 wt %.
Embodiment 9
[0142] The process of any of the above embodiments, wherein the
feedstream has a multi-ring aromatics content of at least about 40
wt %, or at least about 45 wt %, or at least about 50 wt %.
Embodiment 10
[0143] The process of any of the above embodiments, wherein the
catalyst precursor composition is treated first with said first
organic compound and second with said second organic compound, or
wherein the catalyst precursor composition is treated first with
said second organic compound and second with said first organic
compound, or wherein the catalyst precursor composition is treated
simultaneously with said first organic compound and with said
second organic compound.
Embodiment 11
[0144] The process of any of the above embodiments, wherein said at
least one metal from Group 6 is Mo, W, or a combination thereof,
and wherein said at least one metal from Groups 8-10 is Co, Ni, or
a combination thereof.
Embodiment 12
[0145] The process of any of the above embodiments, wherein the
mixed metal catalyst precursor composition is a bulk metal
hydroprocessing catalyst precursor composition consisting
essentially of the reaction product, an oxide form of the at least
one metal from Group 6, an oxide form of the at least one metal
from Groups 8-10, and optionally about 20 wt % or less of a
binder.
Embodiment 13
[0146] The process of any of Embodiments 4-12, wherein the first
stage hydroprocessing conditions, the second stage hydroprocessing
conditions, or both the first stage and the second stage
hydroprocessing conditions comprise effective hydroprocessing
conditions, the effective hydroprocessing conditions comprising
temperatures of about 200.degree. C. to about 450.degree. C.;
pressures of about 250 psig (1.8 MPag) to about 5000 psig (34.6
MPag); liquid hourly space velocities (LHSV) of about 0.1 hr.sup.1
to about 10 hr.sup.-1; and hydrogen treat rates of about 200 scf/B
(35.6 m.sup.3/m.sup.3) to about 10,000 scf/B (1781
m.sup.3/m.sup.3), the first stage and second stage hydroprocessing
conditions optionally but preferably being selected
independently.
Embodiment 14
[0147] The process of any of the above embodiments, wherein a T10
boiling point of the feedstream is at least about 350.degree. F.
(177.degree. C.), or at least about 400.degree. F. (204.degree.
C.), or at least about 450.degree. F. (232.degree. C.); or wherein
the T90 boiling point of the feedstream is about 850.degree. F.
(454.degree. C.) or less, or about 800.degree. F. (427.degree. C.)
or less, or about 750.degree. F. (399.degree. C.) or less, or about
700.degree. F. (371.degree. C.) or less; or a combination
thereof.
Embodiment 15
[0148] The process of any of the above embodiments, further
comprising performing catalytic dewaxing, hydrofinishing, aromatic
saturation, or a combination thereof on at least a portion of the
second liquid product stream.
Embodiment 16
[0149] The process of Embodiment 15, wherein the catalytic dewaxing
is performed at effective catalytic dewaxing conditions comprising
temperatures of about 200.degree. C. to about 450.degree. C.,
hydrogen partial pressures of about 1.8 MPag to about 34.6 MPag
(250 psig to 5000 psig), liquid hourly space velocities of from
0.05 h.sup.-1 to 10 h.sup.-1, and hydrogen treat gas rates of about
35.6 m.sup.3/m.sup.3 (200 SCF/B) to about 1781 m.sup.3/m.sup.3
(10,000 scf/B).
Embodiment 17
[0150] The process of Embodiment 15 or 16, wherein the
hydrofinishing is performed at effective hydrofinishing conditions
comprise temperatures from about 125.degree. C. to about
425.degree. C., total pressures from about 500 psig (3.4 MPa) to
about 3000 psig (20.7 MPa), liquid hourly space velocities from
about 0.1 hr.sup.-1 to about 5 hr.sup.-1 LHSV, and hydrogen treat
gas rates of from 500 to 5000 scf/B (89 to 890
m.sup.3/m.sup.3).
Embodiment 18
[0151] The process of Embodiment 15 or 16 or 17, wherein the
aromatic saturation is performed at effective aromatic saturation
conditions comprising temperatures from about 200.degree. C. to
about 425.degree. C., total pressures from about 500 psig (3.4 MPa)
to about 3000 psig (20.7 MPa), liquid hourly space velocities from
about 0.1 hr.sup.-1 to about 5 hr.sup.-1 LHSV, and hydrogen treat
gas rates of from 500 to 5000 sc/B (89 to 890 m.sup.3/m.sup.3).
Embodiment 19
[0152] The process of any of Embodiments 4-18, wherein the first
stage hydrotreating conditions are effective for conversion of
about 10 wt %/o or less of the feedstream relative to a conversion
temperature of about 350.degree. F. (177.degree. C.), or wherein
the second stage hydrotreating conditions are effective for
conversion of about 10 wt % or less of the feedstream relative to a
conversion temperature of about 350.degree. F. (177.degree. C.), or
wherein about 10 wt % or less of the feedstream is converted
relative to a conversion temperature of 350.degree. F. (177.degree.
C.) during the reacting in the first hydrotreating stage and the
second hydrotreating stage, or a combination thereof.
Embodiment 20
[0153] The process of any of the above embodiments, wherein the T90
boiling point of the first liquid product stream is about
800.degree. F. (427.degree. C.) or less, or about 750.degree. F.
(399.degree. C.) or less, or about 700.degree. F. (371.degree. C.)
or less.
Embodiment 21
[0154] A hydrotreatment process comprising: reacting a naphtha
boiling range feedstream comprising a cracked naphtha portion in
the presence of a hydrogen-containing treat gas and in the presence
of a mixed metal catalyst under effective hydrotreating conditions;
and separating the first liquid effluent to produce a vapor phase
stream and a liquid product stream, the liquid product stream
having a sulfur content of about 100 wppm or less, wherein the
mixed metal catalyst comprises a sulfided mixed metal catalyst
formed by sulfiding a mixed metal catalyst precursor composition,
the mixed metal catalyst precursor composition being produced by a)
heating a composition comprising at least one metal from Group 6 of
the Periodic Table of the Elements, at least one metal from Groups
8-10 of the Periodic Table of the Elements, and a reaction product
formed from (i) a first organic compound containing at least one
amine group, and (ii) a second organic compound separate from said
first organic compound and containing at least one carboxylic acid
group to a temperature from about 195.degree. C. to about
260.degree. C. for a time sufficient for the first and second
organic compounds to form a reaction product in situ that contains
an amide moiety, unsaturated carbon atoms not present in the first
or second organic compounds, oxygen atoms not present in the first
or second organic compounds, or a combination thereof; b) heating a
composition comprising one metal from Group 6 of the Periodic Table
of the Elements, at least one metal from Groups 8-10 of the
Periodic Table of the Elements, and a reaction product formed from
(iii) a first organic compound containing at least one amine group
and at least 10 carbon atoms or (iv) a second organic compound
containing at least one carboxylic acid group and at least 10
carbon atoms, but not both (iii) and (iv), wherein the reaction
product contains additional unsaturated carbon atoms, relative to
(iii) the first organic compound or (iv) the second organic
compound, wherein the metals of the catalyst precursor composition
are arranged in a crystal lattice, and wherein the reaction product
is not located within the crystal lattice, to a temperature from
about 195.degree. C. to about 260.degree. C. for a time sufficient
for the first or second organic compounds to form a reaction
product in situ that contains unsaturated carbon atoms not present
in the first or second organic compounds, oxygen atoms not present
in the first or second organic compounds, or a combination thereof;
or c) heating a composition comprising at least one metal from
Group 6 of the Periodic Table of the Elements, at least one metal
from Groups 8-10 of the Periodic Table of the Elements, and a
pre-formed amide formed from (v) a first organic compound
containing at least one amine group, and (vi) a second organic
compound separate from said first organic compound and containing
at least one carboxylic acid group, to form at least one of
additional in situ unsaturated carbon atoms or in situ added oxygen
atoms not present in the first organic compound, the second organic
compound, or both, but not for so long that the pre-formed amide
substantially decomposes, thereby forming a catalyst precursor
containing at least one of in situ formed unsaturated carbon atoms
or in situ added oxygen atoms.
Embodiment 22
[0155] The process of any of Embodiments 4 to 21, wherein reacting
the feedstream or a naphtha boiling range feedstream in the
presence of a mixed metal catalyst further comprises reacting the
feedstream in the presence of one or more additional hydrotreating
catalysts, the one or more additional hydrotreating catalysts and
the mixed metal catalyst optionally comprising a catalyst mixture,
or the one or more additional hydrotreating catalysts and the mixed
metal catalyst optionally comprising a stacked bed of catalysts, or
the one or more additional hydrotreating catalysts and the mixed
metal catalyst optionally being located in separate catalyst beds,
or a combination thereof.
EXAMPLES
[0156] The following examples illustrate various methods for
increasing distillate yield based in part on additional aromatic
saturation of an appropriate feed. In some examples, distillate
yield can be improved based on use of a catalyst with improved
activity for aromatic saturation at a desired level of severity for
removal of heteroatoms. In other examples, distillate yield can be
improved based on using interstage separation prior to a second (or
subsequent) hydrotreating stage.
Example 1
Distillate Hydrotreating with Interstage Separation
[0157] To demonstrate the benefits of using interstage separation
for distillate hydrotreating, a light cycle oil was hydrotreated
under a series of conditions. Various properties of the light cycle
oil feed prior to the initial hydrotreatment stage are shown in
Table 1. In addition to the properties in Table 1, the light cycle
oil had a T5 boiling point of about 412.degree. F. (211.degree.
C.), a T95 boiling point of about 724.degree. F. (384.degree. C.),
and a final boiling point of about 788.degree. F. (420.degree.
C.).
[0158] In an initial stage, the light cycle oil was hydrotreated to
reduce the sulfur content, nitrogen content, and specific gravity
of the liquid product. The effluent from the initial stage was
either cascaded into second hydrotreatment stage without stripping
or other intermediate separation as shown in process configuration
FIG. 1, or was separated to separate the liquid product from the
gas phase portion of the effluent and the liquid phase product was
then hydrotreated in a second reaction stage as shown in process
configuration FIG. 2. The hydrotreating catalyst in both stages was
a commercially available supported NiMo distillate hydrotreating
catalyst.
[0159] The liquid phase effluent from the first stage was
hydrotreated using a treat gas containing substantially no H.sub.2S
to simulate the two stage hydroprocessing with intermediate
separation, such as the configuration shown in FIG. 2, and a treat
gas containing about 2 vol % H.sub.2S to simulate the two stage
hydroprocessing without intermediate separation, such as the
configuration shown in FIG. 1. As shown in Table 1, the liquid
product from the second hydrotreating stage has a substantially
lower aromatics content than the feed to the initial hydrotreating
stage. Additionally, the aromatics present in the liquid product
from the second hydrotreating stage are primarily 1-ring aromatics.
This is in contrast to the initial feed, where the majority of the
aromatics are multi-ring aromatics.
[0160] The reduction in multi-ring aromatics in the final product
as H.sub.2S is removed from the treat gas (as shown in Table 1) is
believed to contribute to the reduced specific gravity (or
increased API gravity) of the liquid products formed during
hydrotreatment with lower concentrations of H.sub.2S and/or no
H.sub.2S in the treat gas. The change in specific gravity shown in
Table 1 corresponds to about a 0.44 vol % increase for the volume
of liquid product generated with no H.sub.2S in the second stage
treat gas relative to the volume of liquid product generated with 2
vol % H.sub.2S in the second stage treat gas. The reduction in
multi-ring aromatics also causes a corresponding increase in the
amount of H.sub.2 consumed during the second stage hydrotreatment.
It is noted that the net conversion of the distillate feed relative
to a conversion temperature of 350.degree. F. (177.degree. C.)
appears to be relatively unaffected by the amount of H.sub.2S
present in the second hydrotreating stage, at least for H.sub.2S
amounts of about 2 vol % or less. Thus, the increase in distillate
yield appears to be achieved at a substantially constant level of
process severity.
TABLE-US-00001 TABLE 1 Light Cycle Oil Feed and Hydrotreated
Product Properties Feed Product 1 Product 2 Process Conditions
Treat Gas H.sub.2S Content, vol % 0 2 Temperature, F. 655 656
Pressure, psig 1637 1632 LHSV, hr.sup.-1 0.76 0.77 Treat Gas Rate,
SCF/B 4431 4405 Treat Gas Purity, % H.sub.2 80 78 Product
Properties S, ppm 20100 9.5 19 N, wppm 708 0.4 0.4 API 16.5 28.4
27.7 SpGr, g/ml 0.9561 0.8849 0.8888 Aromatics, wt % 1 Ring 18.7
48.3 52.1 2 Ring 40.9 3.8 4.5 3+ Ring 13.1 0.5 0.4 Total 72.7 52.6
57 Hydrogen Consumption, scf/bbl 1708 1589 350+% conversion, wt %
2.22% 2.28%
[0161] As an example of the commercial benefit, an example of a
suitable feed for commercial distillate hydrotreater can be a feed
containing about 30 vol % light cycle oil, such as the light cycle
oil used for the processes shown in Table 1, with the remaining
portion of the feed corresponding to a virgin gas oil having a
roughly comparable boiling range. For this type of feed, a 0.44 vol
% increase in the product resulting from the light cycle oil
portion (30 vol %) of the feed can correspond to about 23,100
barrels of additional distillate product per year generated by a
50,000 barrel per day distillate hydrotreater under typical
operating conditions.
Example 2
Hydrotreating of Light Vacuum Gas Oil with Mixed Metal Catalyst
[0162] A mixed metal catalyst formed from a suitable precursor can
also be used to improve aromatic saturation during distillate
hydrotreating. In Examples 2 and 3, various feeds were hydrotreated
in a single processing stage (i.e., no separation to remove
H.sub.2S) using various catalysts or catalyst systems.
[0163] In a first distillate hydrotreating process, a straight run
light vacuum gas oil feed was hydrotreated in a single stage
distillate hydrotreating system. The catalyst in the reaction
system was a stacked bed of a commercial NiMo supported
hydrotreating catalyst, a mixed metal catalyst formed from a
suitable precursor, and the commercial NiMo supported hydrotreating
catalyst. About one third of the catalyst volume corresponded to
the mixed metal catalyst, with the mixed metal catalyst being
approximately in the middle of the catalyst bed. For comparison,
the straight run light vacuum gas oil was hydrotreated in a similar
reaction system with a catalyst bed composed only of the commercial
NiMo supported hydrotreating catalyst.
TABLE-US-00002 TABLE 2 Process Conditions for Distillate
Hydrotreating of Straight Run Feed Stacked Bed Commercial Including
Mixed HDT Straight Run Feed Metal Catalyst catalyst Feed Properties
S, wt % 0.856 N, wppm 242 SpGr 0.8756 1-ring aromatics (wt %) 19.5
2-ring aromatics (wt %) 12.4 3+ ring aromatics (wt %) 2.1 Total
aromatics (wt %) 34 Processing Conditions Temp, .degree. C. 340 340
Pressure, psig 840 840 TGR, SCF/B 560 560 TGR purity, vol % 80 80
LHSV, hr.sup.-1 0.85 0.85 300+ F. Conversion, % 2.2 2.3 Product
Properties Liquid yield, vol % Base + 0.29% Base
[0164] As shown in Table 2, the light vacuum gas oil had an initial
sulfur content of about 0.86 wt % and a specific gravity of about
0.876 g/ml. The light vacuum gas oil was exposed to the catalyst or
catalyst system at 340.degree. C. and at 840 psig (5800 kPa) of
pressure. The treat gas rate was about 560 sc/B (950
Nm.sup.3/m.sup.3) of a gas containing about 80 vol % hydrogen. The
LHSV was about 0.85 hr.sup.-1.
[0165] Under the hydrotreating conditions, the stacked bed catalyst
including the mixed metal catalyst resulted in a liquid product
yield with a volume increase of about 0.29 vol % relative to the
product yield from hydrotreating over just the commercial supported
NiMo catalyst. This increase in volume was achieved with similar
levels of conversion relative to a 300.degree. F. (149.degree. C.)
conversion temperature. This demonstrates the ability of the mixed
metal catalyst to improve yield (volume swell) for a feed having a
sulfur content of less than about 10000 wppm at a roughly constant
level of process severity.
Example 3
Hydrotreating of High Sulfur Content Feeds with a Mixed Metal
Catalyst
[0166] In this example, the impact of sulfur content on yield when
using a mixed metal catalyst is further investigated. Two different
feeds were hydrotreated over hydrotreating catalysts to demonstrate
the yield improvement of the mixed metal catalyst. One
hydrotreating catalyst was a mixed metal catalyst formed from a
suitable precursor, as described herein. A second catalyst was a
bulk NiMoW hydrotreating catalyst made according to the methods
described in U.S. Pat. No. 6,156,695, U.S. Pat. No. 6,582,590
and/or U.S. Pat. No. 6,929,738.
TABLE-US-00003 TABLE 3 Process Conditions for Distillate
Hydrotreating of Partially Cracked Feed Mixed Metal Comparative
Bulk 20% Cracked Feed (LCO) Feed Catalyst Catalyst Processing
Conditions Temp (.degree. C.) ~300 ~300 Pressure (kPa) ~5800 ~5800
Treat Gas Rate (Nm.sup.3/m.sup.3) ~250 ~250 Treat Gas Purity (vol
%) ~100 ~100 LHSV (hr.sup.-1) ~1.2 ~1.2 Product - Liquid Yield (vol
Base + ~0.37% Base %) Product - Sulfur (wppm) ~2600 ~3900 Product -
Nitrogen (wppm) ~80 ~160 Product - API ~30.6 ~30.0 Feed Aromatics
1-ring aromatics (wt %) 19.7 2-ring aromatics (wt %) 22.1 3+ ring
aromatics (wt %) 4.4 Total aromatics (wt %) 46.3
[0167] Table 3 shows the processing conditions used for single
stage hydrotreatment of a feed corresponding to about 20 wt % of a
light cycle oil similar to the feed in Example 1, with the
remainder of the feed corresponding to a straight run light vacuum
gas oil. The feed had an initial sulfur content of about 20,000
wppm, an initial nitrogen content of about 626 wppm, and an initial
API of 26.8. The process conditions for hydrotreatment are also
shown in Table 3.
[0168] As shown in Table 3, the mixed metal catalyst provided a
liquid product yield increase of about 0.37 vol % (roughly
corresponding to the increase in API gravity of 30.6 versus 30.0)
relative to the yield from the comparative bulk catalyst. The
amount of conversion of the feed was similar for both catalysts,
although the mixed metal catalyst also provided superior activity
for sulfur and nitrogen removal. Thus, based on the results in
Table 2 and Table 3, for a given level of process severity, the
mixed metal catalyst formed from a suitable precursor appears to
provide a yield advantage over various conventional catalysts.
[0169] The process conditions and results from processing a feed
composed of only the light cycle oil are shown in Table 4. As shown
in Table 4, the increase in yield using the mixed metal catalyst is
0.93 vol %. As indicated by the process conditions, this yield
increase was again achieved at roughly constant process
severity.
TABLE-US-00004 TABLE 4 Process Conditions for Distillate
Hydrotreating of Cracked Feed 100% Cracked Feed (LCO) Mixed Metal
Comparative Bulk Processing Conditions Temp (.degree. C.) ~295 ~295
Pressure (kPa) ~8300 ~8300 Treat Gas Rate (Nm.sup.3/m.sup.3) ~780
~780 Treat Gas Purity (vol %) ~100 ~100 LHSV (hr.sup.-1) ~2.1 ~2.1
Product - Liquid Yield (vol %) Base + ~0.93% Base
[0170] An additional set of processing runs were performed using a
feed composed of only the light cycle oil are shown in Table 4 but
with a stacked bed catalyst arrangement. The stacked bed included a
sequence of a commercial supported NiMo hydrotreating catalyst,
either the mixed metal catalyst or the comparative bulk catalyst,
and the commercial supported NiMo hydrotreating catalyst, with
about one third of the volume of the catalyst bed corresponding to
each layer. As shown in Table 5, using the mixed metal catalyst in
the stacked bed provided substantial additional API Gravity uplift
(about 0.75.degree.) relative to using the stacked bed with the
comparative bulk catalyst. This additional increase in API Gravity
indicates that the resulting yield also increased. As indicated by
the process conditions, this yield increase was again achieved at
roughly constant process severity.
TABLE-US-00005 TABLE 5 Process Conditions for Stacked Bed
Distillate Hydrotreating of Cracked Feed Stacked Bed Stacked Bed
Including 100% Cracked Feed Including Mixed Comparative Bulk (LCO)
Metal Catalyst Catalyst Feed Properties S, wt % 1.94 N, wppm 834
API Gravity 16.2 Aromatics, wt % 1 Ring 13.6 2 Ring 29.6 3+ Ring
30.9 Total 74.1 Processing Conditions Temp, .degree. C. ~340 ~340
Pressure, kPa ~11000 ~11000 TGR, SCF/B 4400 4400 LHSV, hr-1 0.94
0.94 Product Properties API Gravity 31.05 30.30 S, wppm 20 60 N,
wppm <1 <1
Example 4
Distillate Hydrotreating with Interstage Separation with Mixed
Metal Catalyst
[0171] A mixed metal catalyst formed from a suitable precursor can
also be used in conjunction with interstage separation to achieve
still larger increases in distillate yield. In this example, a
process configuration similar to Example 1 was used, so that a
light cycle oil feed could be processed with interstage separation.
In this Example, the initial hydrotreatment stage included a
conventional supported NiMo catalyst to produce a first stage
hydrotreated liquid product having the properties shown in Table 6.
The first stage hydrotreated liquid product was then hydrotreated
using either the mixed metal catalyst formed from a suitable
precursor or the comparative bulk NiMoW catalyst made according to
the methods described in U.S. Pat. No. 6,156,695, U.S. Pat. No.
6,582,590 and/or U.S. Pat. No. 6,929,738. The process conditions
and resulting product properties are shown in Table 6.
TABLE-US-00006 TABLE 6 Second Stage Distillate Hydrotreating of
Cracked Feed after Separation Total Liquid Product after
Comparative Bulk Mixed Metal Conditions first stage Catalyst
Catalyst LHSV (hr.sup.-1) ~1 ~1 Temp (.degree. C.) ~300 ~300 Treat
Gas Rate (Nm.sup.3/m.sup.3) ~820 ~820 H.sub.2 Pressure (kPa) ~8300
~8300 Product Sulfur (wppm) ~3940 ~140 ~25 Product Nitrogen (wppm)
~275 ~0.3 <0.2 API Gravity ~22.12 ~27.20 ~29.10
[0172] As shown in Table 6, at a similar level of conversion
relative to a conversion temperature of 350.degree. F. (177.degree.
C.), the mixed metal catalyst produced a liquid product with a
yield about 1.9 vol % greater than the liquid product from
hydrotreating with the comparative bulk catalyst. This is almost a
doubling of the volume swell benefit relative to the processing of
the cracked feed as shown in Table 4 of Example 3. Such a volume
swell benefit is unexpectedly larger than the benefit that would be
expected based on mere addition of the volume swell provided by the
mixed metal catalyst and the volume swell provided by two stage
hydrotreatment with interstage separation. This shows that the
benefits of interstage separation can be synergistically combined
with use of a mixed metal catalyst to provide an unexpectedly
larger yield increase during distillate hydrotreating of a high
sulfur distillate boiling range feed. This also demonstrates that
the benefits of interstage separation can be realized for a variety
of types of hydrotreating catalysts.
Example 5
Hydrocracker Pre-Treatment
[0173] A feed corresponding to about 70% of a cycle oil and about
30% of a gas oil was processed under the conditions shown in Table
7 in a fixed bed reactor over a stacked bed of catalyst. The
stacked bed included a sequence of a commercial supported NiMo
hydrotreating catalyst, either the mixed metal catalyst or the
comparative bulk catalyst, and the commercial supported NiMo
hydrotreating catalyst, with about one third of the volume of the
catalyst bed corresponding to each layer. Table 7 also shows
details regarding the feed and product quality from the processing
runs.
TABLE-US-00007 TABLE 7 Stacked Bed Hydroprocessing of Heavy
Partially Cracked Feed Stacked Bed Stacked Bed Including Including
Mixed Metal Comparative 70% Cycle Oil/30% VGO Catalyst Bulk
Catalyst Feed Properties S, wt % 3.32 N, wppm 905 SpGr 0.9616 API
Gravity 16.2 Processing Conditions Temp, .degree. C. ~325 ~325
Pressure, kPa ~9400 ~9400 TGR, SCF/B 5600 5600 Hydrogen Consumption
~1620 ~1430 (SCF/B) LHSV, hr.sup.-1 1.4 1.4 Product Properties SpGr
0.894 0.901 API Gravity 26.7 25.4 S, wppm ~390 ~970 N, wppm <1
<1
[0174] As shown in Table 7, at processing conditions with
comparable severity, the stacked bed including the mixed metal
catalyst produced an additional increase in API Gravity of more
than about 1.degree. relative to processing over the stacked bed
including the comparative bulk catalyst. Processing over the
stacked bed with the mixed metal catalyst also resulted in greater
consumption of hydrogen. Table 8 shows that this additional
hydrogen consumption appears to be correlated with an increase in
the number of aromatic compounds that were converted to naphthenes
during processing over the stacked bed with the mixed metal
catalyst.
TABLE-US-00008 TABLE 8 Total Liquid Product Composition from
Stacked Bed Hydroprocessing of Heavy Partially Cracked Feed Stacked
Bed Stacked Bed Including 70% Cycle Oil/30% VGO Including Mixed
Comparative Bulk Composition (wt %) Metal Catalyst Catalyst
Paraffins ~9.2 ~9.3 Naphthenes ~37.5 ~30.8 Total Aromatics ~53.3
~59.9 1-ring Aromatics ~40.5 ~43.7 2-ring Aromatics ~9.0 ~11.0
3-ring Aromatics ~3.9 ~5.3
Example 6
Naphtha Hydrotreatment
[0175] The mixed metal catalyst can also provide advantages when
used for hydrotreatment of naphtha boiling range feeds. A feed
corresponding to a catalytically cracked naphtha was processed
under the conditions shown in Table 9 in a fixed bed reactor over a
stacked bed of catalyst. The stacked bed included a sequence of a
commercial supported NiMo hydrotreating catalyst, either the mixed
metal catalyst or the comparative bulk catalyst, and the commercial
supported NiMo hydrotreating catalyst, with about one third of the
volume of the catalyst bed corresponding to each layer. It is noted
that the conditions for processing using the comparative bulk
catalyst were of higher severity due to the increased pressure of
3000 kPa. Table 9 also shows details regarding the feed and product
quality from the processing runs. As shown in Table 9, even at the
milder conditions associated with naphtha hydrotreating, the mixed
metal catalyst provided a benefit in activity for
hydrodesulfurization and aromatic saturation. Processing the
cracked naphtha feed over the stacked bed including the mixed metal
catalyst also provided some additional increase in API Gravity
relative to processing over the stacked bed including the
comparative bulk catalyst.
TABLE-US-00009 TABLE 9 Naphtha Hydrotreating Stacked Bed 100%
Catalytically Stacked Bed Including Cracked Naphtha Including Mixed
Comparative Bulk Conditions Feed Metal Catalyst Catalyst LHSV
(hr.sup.-1) ~4 ~4 Temp (.degree. C.) ~275 ~275 Treat Gas Rate
(SCF/B) ~1000 ~1000 H.sub.2 Pressure (kPa) ~2000 ~3000 Sulfur
(wppm) ~2330 ~19 ~42 API Gravity ~40.6 ~41.87 ~41.72
[0176] Although the present invention has been described in terms
of specific embodiments, it is not so limited. Suitable
alterations/modifications for operation under specific conditions
should be apparent to those skilled in the art. It is therefore
intended that the following claims be interpreted as covering all
such alterations/modifications as fall within the true spirit/scope
of the invention.
* * * * *