U.S. patent application number 14/882582 was filed with the patent office on 2016-02-04 for hydroprocessing catalyst and hydroprocessing catalyst of making the same.
The applicant listed for this patent is CHEVRON U.S.A. INC.. Invention is credited to Theodorus Ludovicus Michael MAESEN, Hye Kyung Cho TIMKEN, Bi-Zeng ZHAN.
Application Number | 20160030934 14/882582 |
Document ID | / |
Family ID | 43411699 |
Filed Date | 2016-02-04 |
United States Patent
Application |
20160030934 |
Kind Code |
A1 |
ZHAN; Bi-Zeng ; et
al. |
February 4, 2016 |
HYDROPROCESSING CATALYST AND HYDROPROCESSING CATALYST OF MAKING THE
SAME
Abstract
The present invention is directed to a hydroprocessing catalyst
containing at least one catalyst support, one or more metals,
optionally one or more molecular sieves, optionally one or more
promoters, wherein deposition of at least one of the metals is
achieved in the presence of a modifying agent.
Inventors: |
ZHAN; Bi-Zeng; (Albany,
CA) ; MAESEN; Theodorus Ludovicus Michael; (Moraga,
CA) ; TIMKEN; Hye Kyung Cho; (Albany, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CHEVRON U.S.A. INC. |
San Ramon |
CA |
US |
|
|
Family ID: |
43411699 |
Appl. No.: |
14/882582 |
Filed: |
October 14, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12496442 |
Jul 1, 2009 |
9187702 |
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14882582 |
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Current U.S.
Class: |
502/62 |
Current CPC
Class: |
B01J 31/0238 20130101;
B01J 35/1038 20130101; B01J 2229/42 20130101; B01J 35/1066
20130101; B01J 31/04 20130101; B01J 35/1042 20130101; B01J 2229/34
20130101; B01J 29/146 20130101; C10G 45/12 20130101; B01J 31/0237
20130101; B01J 31/0207 20130101; C10G 49/04 20130101; B01J 37/0203
20130101; C10G 45/04 20130101; C10G 45/00 20130101; C10G 45/54
20130101; B01J 2229/20 20130101; C10G 2400/04 20130101; B01J
31/0201 20130101; B01J 35/1047 20130101; C10G 49/06 20130101; C10G
2300/4018 20130101; B01J 29/084 20130101; C10G 47/06 20130101; B01J
29/126 20130101; B01J 35/1019 20130101; B01J 31/0249 20130101; B01J
31/0244 20130101; B01J 31/0209 20130101; B01J 29/166 20130101; B01J
29/106 20130101; C10G 47/12 20130101; B01J 21/12 20130101; C10G
49/08 20130101; B01J 35/1023 20130101; B01J 35/1061 20130101; B01J
2231/641 20130101; C10G 47/14 20130101 |
International
Class: |
B01J 31/02 20060101
B01J031/02; B01J 35/10 20060101 B01J035/10; B01J 29/16 20060101
B01J029/16 |
Claims
1. A hydroprocessing catalyst, comprising: at least one molecular
sieve which is a Y zeolite with a unit cell size of between 24.15
.ANG. and 24.45 .ANG.; and at least one metal deposited on an
amorphous silica-alumina catalyst support containing SiO.sub.2 in
an amount of 10 wt. % to 70 wt. % of the dry bulk weight of the
carrier as determined by ICP elemental analysis, a BET surface area
of between 450 m.sup.2/g and 550 m.sup.2/g, a total pore volume of
between 0.75 mL/g and 1.05 mL/g, and a mean mesopore diameter of
between 70 .ANG. and 130 .ANG.; wherein deposition of the metal is
achieved in the presence of a modifying agent and with the catalyst
support after the deposition subjected to drying for a period of
time ranging from 1 to 5 hours and at a temperature sufficient to
remove impregnation solution solvent but below the decomposition
temperature of the modifying agent.
2. The hydroprocessing catalyst of claim 1, wherein the Y zeolite
has a silica-to-alumina ratio of greater than 10, a micropore
volume of from 0.15 mL/g to 0.27 mL/g, a BET surface area of from
700 m.sup.2/g to 825 m.sup.2/g, and a unit cell size of from 24.15
.ANG. to 24.45 .ANG..
3. The hydroprocessing catalyst of claim 1, wherein Y zeolite has a
silica-to-alumina ratio of greater than 10, a micropore volume of
from 0.15 mL/g to 0.27 mL/g, a BET surface area of from 700
m.sup.2/g to 825 m.sup.2/g, and a unit cell size of from 24.15
.ANG. to 24.35 .ANG., and a low-acidity, highly dealuminated
ultrastable Y zeolite having an Alpha value of less than about 5
and Bronsted acidity of from 1 to 40 micro-mole/g.
4. The hydroprocessing catalyst of claim 1, wherein the modifying
agent is selected from the group consisting of compounds
represented by structures (1) through (4), and condensated forms
thereof: ##STR00002## wherein: (1) R.sub.1, R.sub.2 and R.sub.3 are
independently selected from the group consisting of hydrogen;
hydroxyl; methyl; amine; and linear or branched, substituted or
unsubstituted C.sub.1-C.sub.3 alkyl groups, C.sub.1-C.sub.3 alkenyl
groups, C.sub.1-C.sub.3 hydroxyalkyl groups, C.sub.1-C.sub.3
alkoxyalkyl groups, C.sub.1-C.sub.3 aminoalkyl groups,
C.sub.1-C.sub.3 oxoalkyl groups, C.sub.1-C.sub.3 carboxyalkyl
groups, C.sub.1-C.sub.3 aminocarboxyalkyl groups and
C.sub.1-C.sub.3 hydroxycarboxyalkyl groups; (2) R.sub.4 through
R.sub.10 are independently selected from the group consisting of
hydrogen; hydroxyl; and linear or branched, substituted or
unsubstituted C.sub.2-C.sub.3 carboxyalkyl groups; and (3) R.sub.11
is selected from the group consisting of linear or branched,
saturated and unsaturated, substituted or unsubstituted
C.sub.1-C.sub.3 alkyl groups, C.sub.1-C.sub.3 hydroxyalkyl groups,
and C.sub.1-C.sub.3 oxoalkyl groups.
5. The hydroprocessing catalyst of claim 1, wherein the modifying
agent selected from the group consisting of
N,N'-bis(2-aminoethyl)-1,2-ethane-diamine,
2-amino-3-(1H-indol-3-yl)-propanoic acid, benzaldehyde,
[[(carboxymethyl)imino]bis(ethylenenitrilo)]-tetra-acetic acid,
1,2-cyclohexanediamine, 2-hydroxybenzoic acid, thiocyanate,
thiosulfate, thiourea, pyridine, and quinoline.
6. The hydroprocessing catalyst of claim 1, wherein the at least
one metal is selected from the group consisting of elements from
Group 6 and Groups 8 through 10 of the Periodic Table.
7. The hydroprocessing catalyst of claim 6, wherein the at least
one metal is selected from the group consisting of nickel (Ni),
palladium (Pd), platinum (Pt), cobalt (Co), iron (Fe), chromium
(Cr), molybdenum (Mo), tungsten (W), and mixtures thereof.
8. The hydroprocessing catalyst of claim 6, wherein the at least
one metal is at least one metal selected from Group 6 of the
Periodic Table and at least one metal selected from Groups 8
through 10 of the periodic table.
9. A method for making a hydroprocessing catalyst comprising at
least one metal deposited on an amorphous silica-alumina catalyst
support containing SiO.sub.2 in an amount of 10 wt. % to 70 wt. %
of the dry bulk weight of the carrier as determined by ICP
elemental analysis, the hydroprocessing catalyst made by a method
comprising the steps of: (a) forming an extrudable mass comprising
the amorphous silica-alumina catalyst support, (b) extruding then
calcining the mass to form a calcined extrudate, (c) exposing the
calcined extrudate to an impregnation solution comprising the at
least one metal and a modifying agent to form an impregnated
extrudate, and (d) drying the impregnated extrudate for a period of
time ranging from 1 to 5 hours and at a temperature sufficient to
remove impregnation solution solvent but below the decomposition
temperature of the modifying agent.
10. The method of claim 10, wherein the amorphous silica-alumina
catalyst support has a BET surface area of between 450 m.sup.2/g
and 550 m.sup.2/g, a total pore volume of between 0.75 mL/g and
1.05 mL/g, and a mean mesopore diameter of between 70 .ANG. and 130
.ANG.
11. The hydroprocessing catalyst of claim 10, further comprising
the step of calcining the dried impregnated extrudate at a
temperature high enough to remove the modifying agent and
impregnation solution solvent and to convert the at least one metal
to a metal oxide.
12. The hydroprocessing catalyst of claim 10, wherein the
extrudable mass further comprises at least one molecular sieve.
13. The hydroprocessing catalyst of claim 12, wherein the molecular
sieve is a Y zeolite with a unit cell size of between 24.15 .ANG.
and 24.45 .ANG..
14. The hydroprocessing catalyst of claim 12, wherein the at least
one molecular sieve is a Y zeolite having a silica-to-alumina ratio
of greater than 10, a micropore volume of from 0.15 mL/g to 0.27
mL/g, a BET surface area of from 700 m.sup.2/g to 825 m.sup.2/g,
and a unit cell size of from 24.15 .ANG. to 24.45 .ANG..
14. The hydroprocessing catalyst of claim 10, wherein the
extrudable mass further comprises a Y zeolite having a
silica-to-alumina ratio of greater than 10, a micropore volume of
from 0.15 mL/g to 0.27 mL/g, a BET surface area of from 700
m.sup.2/g to 825 m.sup.2/g, and a unit cell size of from 24.15
.ANG. to 24.35 .ANG., and a low-acidity, highly dealuminated
ultrastable Y zeolite having an Alpha value of less than about 5
and Bronsted acidity of from 1 to 40 micro-mole/g.
15. The hydroprocessing catalyst of claim 10, wherein the modifying
agent is selected from the group consisting of compounds
represented by structures (1) through (4), an condensated forms
thereof: ##STR00003## wherein: (1) R.sub.1, R.sub.2 and R.sub.3 are
independently selected from the group consisting of hydrogen;
hydroxyl; methyl; amine; and linear or branched, substituted or
unsubstituted C.sub.1-C.sub.3 alkyl groups, C.sub.1-C.sub.3 alkenyl
groups, C.sub.1-C.sub.3 hydroxyalkyl groups, C.sub.1-C.sub.3
alkoxyalkyl groups, C.sub.1-C.sub.3 aminoalkyl groups,
C.sub.1-C.sub.3 oxoalkyl groups, C.sub.1-C.sub.3 carboxyalkyl
groups, C.sub.1-C.sub.3 aminocarboxyalkyl groups and
C.sub.1-C.sub.3 hydroxycarboxyalkyl groups; (2) R.sub.4 through
R.sub.10 are independently selected from the group consisting of
hydrogen; hydroxyl; and linear or branched, substituted or
unsubstituted C.sub.2-C.sub.3 carboxyalkyl groups; and (3) R.sub.11
is selected from the group consisting of linear or branched,
saturated and unsaturated, substituted or unsubstituted
C.sub.1-C.sub.3 alkyl groups, C.sub.1-C.sub.3 hydroxyalkyl groups,
and C.sub.1-C.sub.3 oxoalkyl groups.
Description
FIELD OF THE INVENTION
[0001] The present invention is directed to a catalyst for
hydroprocessing a carbonaceous feedstock under hydroprocessing
conditions, hydroprocessing catalysts for making the catalyst, and
hydroprocessing processes using the catalyst of the present
invention.
BACKGROUND OF THE INVENTION
[0002] Catalytic hydroprocessing refers to petroleum refining
processes in which a carbonaceous feedstock is brought into contact
with hydrogen and a catalyst, at a higher temperature and pressure,
for the purpose of removing undesirable impurities and/or
converting the feedstock to an improved product. Examples of
hydroprocessing processes include hydrotreating,
hydrodemetalization, hydrocracking and hydroisomerization
processes.
[0003] A hydroprocessing catalyst typically consists of one or more
metals deposited on a support or carrier consisting of an amorphous
oxide and/or a crystalline microporous material (e.g. a zeolite).
The selection of the support and metals depend upon the particular
hydroprocessing process for which the catalyst is employed.
[0004] Petroleum refiners continue to seek out catalysts of
improved activity, selectivity and/or stability. Increasing the
activity of a catalyst increases the rate at which a chemical
reaction proceeds under a given set of conditions, increasing the
selectivity of the catalysts decreases unwanted by-products of the
reaction, and increasing the stability of a catalyst increases its
resistance to deactivation, that is, the useful life of the
catalyst is extended. In general, as the activity of the catalyst
is increased, the conditions required to produce a given end
product, such as a hydrocarbon of a particular sulfur or nitrogen
content, becomes more mild (e.g. decreased temperature). Milder
conditions require less energy to achieve a desired product, and
the catalyst's life is extended due to such factors as lower coke
formation and the like.
[0005] It is well known in the art that modest or slight variations
in compositional characteristics or hydroprocessing catalysts of
preparing hydroprocessing catalysts have been known to have highly
unpredictable activity, selectivity and/or stability effects on
hydroprocessing reactions (such as denitrogenation and/or
desulfurization reactions). Accordingly, because of this
unpredictability in the art, there continues to be new and
surprising improvements in activity, selectivity and/or stability
of hydroprocessing catalysts.
SUMMARY OF THE INVENTION
[0006] The present invention is directed to a hydroprocessing
catalyst containing at least one catalyst support, one or more
metals, optionally one or more molecular sieves, and optionally one
or more promoters, wherein deposition of at least one of the metals
is achieved in the presence of a modifying agent.
[0007] The present invention is also directed to hydroprocessing
catalysts for making the catalyst, and hydroprocessing processes
using the catalyst of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 shows the polycyclic aromatics build up as a function
of time-on-stream for the catalyst compositions synthesized per the
teachings of Examples 1 and 3 herein.
DETAILED DESCRIPTION OF THE INVENTION
Introduction
[0009] The term "Periodic Table" refers to the version of IUPAC
Periodic Table of the Elements dated Jun. 22, 2007, and the
numbering scheme for the Periodic Table Groups is as described in
Chemical and Engineering News, 63(5), 27 (1985).
[0010] The term "bulk dry weight" to the weight of a material after
calcination at elevated temperature of over 1000.degree. C. for 30
minutes.
[0011] The term "hydroprocessing" refers to a process in which a
carbonaceous feedstock is brought into contact with hydrogen and a
catalyst, at a higher temperature and pressure, for the purpose of
removing undesirable impurities and/or converting the feedstock to
a desired product.
[0012] The term "hydrotreating" refers to a process that converts
sulfur- and/or nitrogen-containing hydrocarbon feeds into
hydrocarbon products with reduced sulfur and/or nitrogen content,
typically in conjunction with a hydrocracking function, and which
generates hydrogen sulfide and/or ammonia (respectively) as
byproducts.
[0013] The term "hydrocracking" refers to a process in which
hydrogenation and dehydrogenation accompanies the
cracking/fragmentation of hydrocarbons, e.g., converting heavier
hydrocarbons into lighter hydrocarbons, or converting aromatics
and/or cycloparaffins (naphthenes) into non-cyclic branched
paraffins
[0014] The term "hydroisomerization" refers to a process in which
normal paraffins are isomerized to their more branched counterparts
in the presence of hydrogen over a catalyst.
[0015] The term "hydrodemetalization" refers to a process that
removes undesirable metals from hydrocarbon feeds into hydrocarbon
products with reduced metal content.
[0016] The term "gas-to-liquid" (GTL) refers to a process in which
gas-phase hydrocarbons such as natural gas are converted to
longer-chain hydrocarbons such as diesel fuel via direct conversion
or via syngas as an intermediate, for example using the
Fischer-Tropsch process.
[0017] The term "framework topology" and its preceding three-letter
framework code refers to the Framework Type data provided for the
framework code in "Atlas of Zeolite Types" 6th Edition, 2007.
[0018] The term "alkenyl," as used herein, represents a straight or
branched chain group of one to twelve carbon atoms derived from a
straight or branched chain hydrocarbon containing at least one
carbon-carbon double bond.
[0019] The term "hydroxyalkyl," as used herein, represents one or
more hydroxyl groups attached to the parent molecular moiety
through an alkyl group.
[0020] The term "alkoxyalkyl," as used herein, represents one or
more alkoxy groups attached to the parent molecular moiety through
an alkyl group.
[0021] The term "aminoalkyl," as used herein, represents one or
more amino groups attached to the parent molecular moiety through
an alkyl group.
[0022] The term "oxoalkyl," as used herein, represents one or more
ether groups attached to the parent molecular moiety through an
alkyl group.
[0023] The term "carboxyalkyl," as used herein, represents one or
more carboxyl groups attached to the parent molecular moiety
through an alkyl group.
[0024] The term "aminocarboxyalkyl," as used herein, represents one
or more carboxyl groups and one or more amino groups attached to
the parent molecular moiety through an alkyl group.
[0025] The term "hydroxycarboxyalkyl," as used herein, represents
one or more carboxyl groups and one or more hydroxyl groups
attached to the parent molecular moiety through an alkyl group.
[0026] Where permitted, all publications, patents and patent
applications cited in this application are herein incorporated by
reference in their entirety; to the extent such disclosure is not
inconsistent with the present invention.
[0027] Unless otherwise specified, the recitation of a genus of
elements, materials or other components, from which an individual
component or mixture of components can be selected, is intended to
include all possible sub-generic combinations of the listed
components and mixtures thereof. Also, "include" and its variants
are intended to be non-limiting, such that recitation of items in a
list is not to the exclusion of other like items that may also be
useful in the materials, compositions and hydroprocessing catalysts
of this invention.
[0028] Properties for the materials described herein are determined
as follows:
[0029] (a) Constrained index (CI): indicates the total cracking
conversion of a 50/50 mixture of n-hexane and 3-methyl-pentane by a
sample catalyst at 900.degree. F. (482.degree. C.), 0.68 WHSV.
Samples are prepared according to the hydroprocessing catalyst
described in U.S. Pat. No. 7,063,828 to Zones and Burton, issued
Jun. 20, 2006.
[0030] (b) Bronsted acidity: determined by
isopropylamine-temperature-programmed desorption (IPam TPD) adapted
from the published descriptions by T. J. Gricus Kofke, R. K. Gorte,
W. E. Farneth, J. Catal. 114, 34-45, 1988; T. J. Gricus Kifke, R.
J. Gorte, G. T. Kokotailo, J. Catal. 115, 265-272, 1989; J. G.
Tittensor, R. J. Gorte and D. M. Chapman, J. Catal. 138, 714-720,
1992.
[0031] (c) SiO.sub.2/Al.sub.2O.sub.3 Ratio (SAR): determined by ICP
elemental analysis. A SAR of infinity (.infin.) represents the case
where there is no aluminum in the zeolite, i.e., the mole ratio of
silica to alumina is infinity. In that case the molecular sieve is
comprised of essentially all of silica.
[0032] (d) Surface area: determined by N.sub.2 adsorption at its
boiling temperature. BET surface area is calculated by the 5-point
hydroprocessing catalyst at P/P.sub.0=0.050, 0.088, 0.125, 0.163,
and 0.200. Samples are first pre-treated at 400.degree. C. for 6
hours in the presence of flowing, dry N.sub.2 so as to eliminate
any adsorbed volatiles like water or organics.
[0033] (e) Micropore volume: determined by N.sub.2 adsorption at
its boiling temperature. Micropore volume is calculated by the
t-plot hydroprocessing catalyst at P/P.sub.0=0.050, 0.088, 0.125,
0.163, and 0.200. Samples are first pre-treated at 400.degree. C.
for 6 hours in the presence of flowing, dry N.sub.2 so as to
eliminate any adsorbed volatiles like water or organics.
[0034] (f) Mesopore pore diameter: determined by N.sub.2 adsorption
at its boiling temperature. Mesopore pore diameter is calculated
from N.sub.2 isotherms by the BJH hydroprocessing catalyst
described in E. P. Barrett, L. G. Joyner and P. P. Halenda, "The
determination of pore volume and area distributions in porous
substances. I. Computations from nitrogen isotherms." J. Am. Chem.
Soc. 73, 373-380, 1951. Samples are first pre-treated at
400.degree. C. for 6 hours in the presence of flowing, dry N.sub.2
so as to eliminate any adsorbed volatiles like water or
organics.
[0035] (g) Total pore volume: determined by N.sub.2 adsorption at
its boiling temperature at P/P.sub.0=0.990. Samples are first
pre-treated at 400.degree. C. for 6 hours in the presence of
flowing, dry N.sub.2 so as to eliminate any adsorbed volatiles like
water or organics.
[0036] (h) Unit cell size: determined by X-ray powder
diffraction.
[0037] (i) Alpha value: determined by an Alpha test adapted from
the published descriptions of the Mobil Alpha test (P. B. Weisz and
J. N. Miale, J. Catal., 4, 527-529, 1965; J. N. Miale, N. Y. Chen,
and P. B. Weisz, J. Catal., 6, 278-87, 1966). The "Alpha Value" is
calculated as the cracking rate of the sample in question divided
by the cracking rate of a standard silica alumina sample. The
resulting "Alpha" is a measure of acid cracking activity which
generally correlates with number of acid sites.
Hydroprocessing Catalyst Composition
[0038] The present invention is directed to a hydroprocessing
catalyst containing at least one catalyst support, one or more
metals, optionally one or more molecular sieves, and optionally one
or more promoters, wherein deposition of at least one of the metals
is achieved in the presence of a modifying agent.
[0039] For each embodiment described herein, the catalyst support
is selected from the group consisting of alumina, silica, zirconia,
titanium oxide, magnesium oxide, thorium oxide, beryllium oxide,
alumina-silica, alumina-titanium oxide, alumina-magnesium oxide,
silica-magnesium oxide, silica-zirconia, silica-thorium oxide,
silica-beryllium oxide, silica-titanium oxide, titanium
oxide-zirconia, silica-alumina-zirconia, silica-alumina-thorium
oxide, silica-alumina-titanium oxide or silica-alumina-magnesium
oxide, preferably alumina, silica-alumina, and combinations
thereof.
[0040] In one subembodiment, the catalyst support is an alumina
selected from the group consisting of .gamma.-alumina,
.eta.-alumina, .theta.-alumina, .delta.-alumina, .chi.-alumina, and
mixtures thereof.
[0041] In another subembodiment, the catalyst support is an
amorphous silica-alumina material in which the mean mesopore
diameter is between 70 .ANG. and 130 .ANG..
[0042] In another subembodiment, the catalyst support is an
amorphous silica-alumina material containing SiO.sub.2 in an amount
of 10 to 70 wt. % of the bulk dry weight of the carrier as
determined by ICP elemental analysis, a BET surface area of between
450 and 550 m.sup.2/g and a total pore volume of between 0.75 and
1.05 mL/g.
[0043] In another subembodiment, the catalyst support is an
amorphous silica-alumina material containing SiO.sub.2 in an amount
of 10 to 70 wt. % of the bulk dry weight of the carrier as
determined by ICP elemental analysis, a BET surface area of between
450 and 550 m.sup.2/g, a total pore volume of between 0.75 and 1.05
mL/g, and a mean mesopore diameter is between 70 .ANG. and 130
.ANG..
[0044] In another subembodiment, the catalyst support is a highly
homogeneous amorphous silica-alumina material having a surface to
bulk silica to alumina ratio (S/B ratio) of 0.7 to 1.3, and a
crystalline alumina phase present in an amount no more than about
10 wt. %.
S / B Ratio = ( Si / Al atomic ratio of the surface measured by XPS
) ( Si / Al atomic of the bulk measured by elemental analysis )
##EQU00001##
[0045] To determine the S/B ratio, the Si/Al atomic ratio of the
silica-alumina surface is measured using x-ray photoelectron
spectroscopy (XPS). XPS is also known as electron spectroscopy for
chemical analysis (ESCA). Since the penetration depth of XPS is
less than 50 .ANG., the Si/Al atomic ratio measured by XPS is for
the surface chemical composition.
[0046] Use of XPS for silica-alumina characterization was published
by W. Daneiell et al. in Applied Catalysis A, 196, 247-260, 2000.
The XPS technique is, therefore, effective in measuring the
chemical composition of the outer layer of catalytic particle
surface. Other surface measurement techniques, such as Auger
electron spectroscopy (AES) and Secondary-ion mass spectroscopy
(SIMS), could also be used for measurement of the surface
composition.
[0047] Separately, the bulk Si/Al ratio of the composition is
determined from ICP elemental analysis. Then, by comparing the
surface Si/Al ratio to the bulk Si/Al ratio, the S/B ratio and the
homogeneity of silica-alumina are determined. How the SB ratio
defines the homogeneity of a particle is explained as follows. An
S/B ratio of 1.0 means the material is completely homogeneous
throughout the particles. An S/B ratio of less than 1.0 means the
particle surface is enriched with aluminum (or depleted with
silicon), and aluminum is predominantly located on the external
surface of the particles. The S/B ratio of more than 1.0 means the
particle surface is enriched with silicon (or depleted with
aluminum), and aluminum is predominantly located on the internal
area of the particles.
[0048] For each embodiment described herein, the amount of catalyst
support in the hydroprocessing catalyst is from 5 wt. % to 80 wt. %
based on the bulk dry weight of the hydroprocessing catalyst.
[0049] For each embodiment described herein, the hydroprocessing
catalyst may optionally contain one or more molecular sieves
selected from the group consisting of BEA-, ISV-, BEC-, IWR-, MTW-,
*STO-, OFF-, MAZ-, MOR-, MOZ-, AFI-, *NRE-, SSY-, FAU-, EMT-,
ITQ-21-, ERT-, ITQ-33-, and ITQ-37-type molecular sieves, and
mixtures thereof.
[0050] In one subembodiment, the one or more molecular sieves
selected from the group consisting of molecular sieves having a FAU
framework topology, molecular sieves having a BEA framework
topology, and mixtures thereof.
[0051] The amount of molecular sieve material in the
hydroprocessing catalyst is from 0 wt. % to 60 wt. % based on the
bulk dry weight of the hydroprocessing catalyst. In one
subembodiment, the amount of molecular sieve material in the
hydroprocessing catalyst is from 0.5 wt. % to 40% wt. %.
[0052] In one subembodiment, the molecular sieve is a Y zeolite
with a unit cell size of 24.15 .ANG.-24.45 .ANG.. In another
subembodiment, the molecular sieve is a Y zeolite with a unit cell
size of 24.15 .ANG.-24.35 .ANG.. In another subembodiment, the
molecular sieve is a low-acidity, highly dealuminated ultrastable Y
zeolite having an Alpha value of less than 5 and a Bronsted acidity
of from 1 to 40. In one subembodiment, the molecular sieve is a Y
zeolite having the properties described in Table 1 below.
TABLE-US-00001 TABLE 1 Alpha value 0.01-5 CI 0.05-5% Bronsted
acidity 1-40 .mu.mole/g SAR 80-150 surface area 650-750 m.sup.2/g
micropore volume 0.25-0.30 mL/g total pore volume 0.51-0.55 mL/g
unit cell size 24.15-24.35 .ANG.
[0053] In another subembodiment, the molecular sieve is a Y zeolite
having the properties described in Table 2 below.
TABLE-US-00002 TABLE 2 SAR 10-.infin. micropore volume 0.15-0.27
mL/g BET surface area 700-825 m.sup.2/g unit cell size 24.15-24.45
.ANG.
[0054] In another subembodiment, the catalyst contains from 0.1 wt.
% to 40 wt. % (based on the bulk dry weight of the catalyst) of a Y
zeolite having the properties described Table 2 above, and from 1
wt. % to 60 wt. % (based on the bulk dry weight of the catalyst) of
a low-acidity, highly dealuminated ultrastable Y zeolite having an
Alpha value of less than about 5 and Bronsted acidity of from 1 to
40 micro-mole/g.
[0055] As described herein above, the hydroprocessing catalyst of
the present invention contains one or more metals. For each
embodiment described herein, each metal employed is selected from
the group consisting of elements from Group 6 and Groups 8 through
10 of the Periodic Table, and mixtures thereof. In one
subembodiment, each metal is selected from the group consisting of
nickel (Ni), palladium (Pd), platinum (Pt), cobalt (Co), iron (Fe),
chromium (Cr), molybdenum (Mo), tungsten (W), and mixtures thereof.
In another subembodiment, the hydroprocessing catalyst contains at
least one Group 6 metal and at least one metal selected from Groups
8 through 10 of the periodic table. Exemplary metal combinations
include Ni/Mo/W, Ni/Mo, Ni/W, Co/Mo, Co/W, Co/W/Mo and
Ni/Co/W/Mo.
[0056] The total amount of metal oxide material in the
hydroprocessing catalyst is from 0.1 wt. % to 90 wt. % based on the
bulk dry weight of the hydroprocessing catalyst. In one
subembodiment, the hydroprocessing catalyst contains from 2 wt. %
to 10 wt. % of nickel oxide and from 8 wt. % to 40 wt. % of
tungsten oxide based on the bulk dry weight of the hydroprocessing
catalyst.
[0057] A diluent may be employed in the formation of the
hydroprocessing catalyst. Suitable diluents include inorganic
oxides such as aluminum oxide and silicon oxide, titanium oxide,
clays, ceria, and zirconia, and mixture of thereof. The amount of
diluent in the hydroprocessing catalyst is from 0 wt. % to 35 wt. %
based on the bulk dry weight of the hydroprocessing catalyst. In
one subembodiment, the amount of diluent in the hydroprocessing
catalyst is from 0.1 wt. % to 25 wt. % based on the bulk dry weight
of the hydroprocessing catalyst.
[0058] The hydroprocessing catalyst of the present invention may
contain one or more promoters selected from the group consisting of
phosphorous (P), boron (B), fluorine (F), silicon (Si), aluminum
(Al), zinc (Zn), manganese (Mn), and mixtures thereof. The amount
of promoter in the hydroprocessing catalyst is from 0 wt. % to 10
wt. % based on the bulk dry weight of the hydroprocessing catalyst.
In one subembodiment, the amount of promoter in the hydroprocessing
catalyst is from 0.1 wt. % to 5 wt. % based on the bulk dry weight
of the hydroprocessing catalyst.
Preparation of the Hydroprocessing Catalyst
[0059] In the present invention, deposition of at least one of the
metals on the catalyst is achieved in the presence of a modifying
agent. In one embodiment, a shaped hydroprocessing catalyst is
prepared by:
[0060] (a) forming an extrudable mass containing at least the
amorphous silica-alumina catalyst support,
[0061] (b) extruding then calcining the mass to form a calcined
extrudate,
[0062] (c) exposing the calcined extrudate to an impregnation
solution containing at least one metal and a modifying agent to
form an impregnated extrudate, and
[0063] (d) drying the impregnated extrudate at a temperature below
the decomposition temperature of the modifying agent and sufficient
to remove the impregnation solution solvent, to form a dried
impregnated extrudate.
The diluent, promoter and/or molecular sieve (if employed) may be
combined with the carrier when forming the extrudable mass. In
another embodiment, the carrier and (optionally) the diluent,
promoter and/or molecular sieve can be impregnated before or after
being formed into the desired shapes.
[0064] In one embodiment, deposition of at least one of the metals
is achieved in the presence of a modifying agent is selected from
the group consisting of compounds represented by structures (1)
through (4), including condensated forms thereof:
##STR00001##
wherein:
[0065] (1) R.sub.1, R.sub.2 and R.sub.3 are independently selected
from the group consisting of hydrogen; hydroxyl; methyl; amine; and
linear or branched, substituted or unsubstituted C.sub.1-C.sub.3
alkyl groups, C.sub.1-C.sub.3 alkenyl groups, C.sub.1-C.sub.3
hydroxyalkyl groups, C.sub.1-C.sub.3 alkoxyalkyl groups,
C.sub.1-C.sub.3 aminoalkyl groups, C.sub.1-C.sub.3 oxoalkyl groups,
C.sub.1-C.sub.3 carboxyalkyl groups, C.sub.1-C.sub.3
aminocarboxyalkyl groups and C.sub.1-C.sub.3 hydroxycarboxyalkyl
groups;
[0066] (2) R.sub.4 through R.sub.10 are independently selected from
the group consisting of hydrogen; hydroxyl; and linear or branched,
substituted or unsubstituted C.sub.2-C.sub.3 carboxyalkyl groups;
and
[0067] (3) R.sub.11 is selected from the group consisting of linear
or branched, saturated and unsaturated, substituted or
unsubstituted C.sub.1-C.sub.3 alkyl groups, C.sub.1-C.sub.3
hydroxyalkyl groups, and C.sub.1-C.sub.3 oxoalkyl groups.
[0068] Representative examples of modifying agents useful in this
embodiment include 2,3-dihydroxy-succinic acid, ethanedioic acid,
2-hydroxyacetic acid, 2-hydroxy-propanoic acid,
2-hydroxy-1,2,3-propanetricarboxylic acid, methoxyacetic acid,
cis-1,2-ethylene dicarboxylic acid, hydroethane-1,2-dicarboxyic
acid, ethane-1,2-diol, propane-1,2,3-triol, propanedioic acid, and
.alpha.-hydro-.omega.-hydroxypoly(oxyethylene).
[0069] In an alternate embodiment, deposition of at least one of
the metals is achieved in the presence of a modifying agent
selected from the group consisting of
N,N'-bis(2-aminoethyl)-1,2-ethane-diamine,
2-amino-3-(1H-indol-3-yl)-propanoic acid, benzaldehyde,
[[(carboxymethyl)imino]bis(ethylenenitrilo)]-tetra-acetic acid,
1,2-cyclohexanediamine, 2-hydroxybenzoic acid, thiocyanate,
thiosulfate, thiourea, pyridine, and quinoline.
[0070] The modifying agent impedes metal aggregation, thereby
enhancing the activity and selectivity of the catalyst.
[0071] For each embodiment described herein, the amount of
modifying agent in the pre-calcined hydroprocessing catalyst is
from 2 wt. % to 18 wt. % based on the bulk dry weight of the
hydroprocessing catalyst.
[0072] The calcination of the extruded mass will vary depending on
the particular support selected. Typically, the extruded mass can
be calcined at a temperature between 752.degree. F. (400.degree.
C.) and 1200.degree. F. (650.degree. C.) for a period of between 1
and 3 hours.
[0073] Non-limiting examples of suitable solvents include water and
C.sub.1 to C.sub.3 alcohols. Other suitable solvents can include
polar solvents such as alcohols, ethers, and amines Water is a
preferred solvent. It is also preferred that the metal compounds be
water soluble and that a solution of each be formed, or a single
solution containing both metals be formed. The modifying agent can
be prepared in a suitable solvent, preferably water. The three
solvent components can be mixed in any sequence. That is, all three
can be blended together at the same time, or they can be
sequentially mixed in any order. In an embodiment, it is preferred
to first mix the one or more metal components in an aqueous media,
than add the modifying agent.
[0074] The amount of metal precursors and modifying agent in the
impregnation solution should be selected to achieve preferred
ratios of metal to modifying agent in the catalyst precursor after
drying.
[0075] The calcined extrudate is exposed to the impregnation
solution until incipient wetness is achieved, typically for a
period of between 1 and 100 hours (more typically between 1 and 5
hours) at room temperature to 212.degree. F. (100.degree. C.) while
tumbling the extrudates, following by aging for from 0.1 to 10
hours, typically from about 0.5 to about 5 hours.
[0076] The drying step is conducted at a temperature sufficient to
remove the impregnation solution solvent, but below the
decomposition temperature of the modifying agent. In another
embodiment, the dried impregnated extrudate is then calcined at a
temperature above the decomposition temperature of the modifying
agent, typically from about 500.degree. F. (260.degree. C.) to
1100.degree. F. (590.degree. C.), for an effective amount of time,
to convert the metals to metal oxides. The present invention
contemplates that when the impregnated extrudate is to be calcined,
it will undergo drying during the period where the temperature is
being elevated or ramped to the intended calcination temperature.
This effective amount of time will range from about 0.5 to about 24
hours, typically from about 1 to about 5 hours. The calcination can
be carried out in the presence of a flowing oxygen-containing gas
such as air, a flowing inert gas such as nitrogen, or a combination
of oxygen-containing and inert gases.
[0077] The dried and calcined hydroprocessing catalysts of the
present invention can be sulfided to form an active catalyst.
Sulfiding of the catalyst precursor to form the catalyst can be
performed prior to introduction of the catalyst into a reactor
(thus ex-situ presulfiding), or can be carried out in the reactor
(in-situ sulfiding).
[0078] Suitable sulfiding agents include elemental sulfur, ammonium
sulfide, ammonium polysulfide ([(NH.sub.4).sub.2S.sub.x), ammonium
thiosulfate ((NH.sub.4).sub.2S.sub.2O.sub.3), sodium thiosulfate
(Na.sub.2S.sub.2O.sub.3), thiourea CSN.sub.2H.sub.4, carbon
disulfide, dimethyl disulfide (DMDS), dimethyl sulfide (DMS),
dibutyl polysulfide (DBPS), mercaptanes, tertiarybutyl polysulfide
(PSTB), tertiarynonyl polysulfide (PSTN), aqueous ammonium
sulfide.
[0079] Generally, the sulfiding agent is present in an amount in
excess of the stoichiometric amount required to form the sulfided
catalyst. In another embodiment, the amount of sulfiding agent
represents a sulphur to metal mole ratio of at least 3 to 1 to
produce a sulfided catalyst.
[0080] The catalyst is converted into an active sulfided catalyst
upon contact with the sulfiding agent at a temperature of
150.degree. F. to 900.degree. F. (66.degree. C. to 482.degree. C.),
from 10 minutes to 15 days, and under a H.sub.2-containing gas
pressure of 101 kPa to 25,000 kPa. If the sulfidation temperature
is below the boiling point of the sulfiding agent, the process is
generally carried out at atmospheric pressure. Above the boiling
temperature of the sulfiding agent/optional components, the
reaction is generally carried out at an increased pressure. As used
herein, completion of the sulfidation process means that at least
95% of stoichiometric sulfur quantity necessary to convert the
metals into for example, Co.sub.9S.sub.8, MoS.sub.2, WS.sub.2,
Ni.sub.3S.sub.2, etc., has been consumed.
[0081] In one embodiment, the sulfiding can be carried out to
completion in the gaseous phase with hydrogen and a
sulfur-containing compound which is decomposable into H.sub.2S.
Examples include mercaptanes, CS.sub.2, thiophenes, DMS, DMDS and
suitable S-containing refinery outlet gasses. The gaseous mixture
of H.sub.2 and sulfur containing compound can be the same or
different in the steps. The sulfidation in the gaseous phase can be
done in any suitable manner, including a fixed bed process and a
moving bed process (in which the catalyst moves relative to the
reactor, e.g., ebullated process and rotary furnace).
[0082] The contacting between the catalyst precursor with hydrogen
and a sulfur-containing compound can be done in one step at a
temperature of 68.degree. F. to 700.degree. F. (20.degree. C. to
371.degree. C.) at a pressure of 101 kPa to 25,000 kPa for a period
of 1 to 100 hrs. Typically, sulfidation is carried out over a
period of time with the temperature being increased or ramped in
increments and held over a period of time until completion.
[0083] In another embodiment of sulfidation in the gaseous phase,
the sulfidation is done in two or more steps, with the first step
being at a lower temperature than the subsequent step(s).
[0084] In one embodiment, the sulfidation is carried out in the
liquid phase. At first, the catalyst precursor is brought in
contact with an organic liquid in an amount in the range of 20% to
500% of the catalyst total pore volume. The contacting with the
organic liquid can be at a temperature ranging from ambient to
248.degree. F. (120.degree. C.). After the incorporation of an
organic liquid, the catalyst precursor is brought into contact with
hydrogen and a sulfur-containing compound.
[0085] In one embodiment, the organic liquid has a boiling range of
200.degree. F. to 1200.degree. F. (93.degree. C. to 649.degree.
C.). Exemplary organic liquids include petroleum fractions such as
heavy oils, lubricating oil fractions like mineral lube oil,
atmospheric gas oils, vacuum gas oils, straight run gas oils, white
spirit, middle distillates like diesel, jet fuel and heating oil,
naphthas, and gasoline. In one embodiment, the organic liquid
contains less than 10 wt. % sulfur, and preferably less than 5 wt.
%.
Hydroprocessing Processes and Feeds
[0086] The catalyst composition according to the invention can be
used in the dry or calcined form, in virtually all hydroprocessing
processes to treat a plurality of feeds under wide-ranging reaction
conditions, e.g., at temperatures in the range of 200.degree. to
450.degree. C., hydrogen pressures in the range of 5 to 300 bar,
and space velocities (LHSV) in the range of 0.05 to 10 h.sup.-1.
The hydroprocessing catalyst composition of the invention is
particularly suitable for hydrotreating hydrocarbon feedstocks such
as middle distillates, kero, naphtha, vacuum gas oils, and heavy
gas oils.
[0087] Using the catalyst of the present invention, heavy petroleum
residual feedstocks, cyclic stocks and other hydrocrackate charge
stocks can be hydrocracked using the process conditions and
catalyst components disclosed in U.S. Pat. No. 4,910,006 and U.S.
Pat. No. 5,316,753. Typically, hydrocracking can be carried out
using the catalyst of the present invention by contacting the
feedstock with hydrogen and the catalyst at a temperature in the
range of 175-485.degree. C., hydrogen pressures in the range of 5
to 300 bar, and LHSV in the range of 0.1-30 h.sup.-1.
[0088] During hydrotreatment, oxygen, sulfur and nitrogen present
in the hydrocarbonaceous feed is reduced to low levels. Aromatics
and olefins, if present in the feed, may also have their double
bonds saturated. In some cases, the hydrotreating catalyst and
hydrotreating conditions are selected to minimize cracking
reactions, which can reduce the yield of the most desulfided
product (typically useful as a fuel).
[0089] Hydrotreating conditions typically include a reaction
temperature between 204-482.degree. C., for example 315-454.degree.
C.; a pressure between 3.5-34.6 Mpa, for example 7.0-20.8 MPa; a
feed rate (LHSV) of 0.5 hr.sup.-1 to 20 hr.sup.-1 (v/v); and
overall hydrogen consumption of 300 to 2000 scf per barrel of
liquid hydrocarbon feed (53.4-356 m.sup.3 H.sub.2/m.sup.3
feed).
[0090] Hydroisomerization conditions are dependent in large measure
on the feed used and upon the desired product. The hydrogen to feed
ratio is typically between 0.089 to 5.34 SCM/liter (standard cubic
meters/liter), for example between 0.178 to 3.56 SCM/liter.
Generally, hydrogen will be separated from the product and recycled
to the reaction zone. Typical feedstocks include light gas oil,
heavy gas oils and reduced crudes boiling above about 177.degree.
C.
[0091] Lube oil may be prepared using the catalyst. For example, a
C.sub.20+ lube oil may be made by hydroisomerizing the paraffin
fraction of the feed. Alternatively, the lubricating oil may be
made by hydrocracking in a hydrocracking zone a hydrocarbonaceous
feedstock to obtain an effluent comprising a hydrocracked oil, and
catalytically dewaxing the effluent at a temperature of at least
about 200.degree. C. and at a pressure between 0.103 and 20.7 Mpa
gauge, in the presence of added hydrogen gas.
[0092] Using the catalyst of the present invention, a FT wax feed
generated from a GTL process can be hydrocracked to diesel and jet
fuels using by contacting the catalyst of the present invention by
the process with hydrogen and the catalyst at a temperature in the
range of 175-485.degree. C., hydrogen pressures in the range of 5
to 300 bar, and LHSV in the range of 0.1-30 h.sup.-1.
[0093] The following examples will serve to illustrate, but not
limit this invention.
Catalyst Preparations
Example 1
Catalyst A--Comparative Hydrocracking Catalyst
[0094] A comparative hydrocracking catalyst was prepared per the
following procedure: 67 parts by weight silica-alumina powder
(obtained from Sasol), 25 parts by weight pseudo boehmite alumina
powder (obtained from Sasol), and 8 parts by weight of zeolite Y
(from Tosoh) were mixed well. A diluted HNO.sub.3 acid aqueous
solution (1 wt. %) was added to the mix powder to form an
extrudable paste. The paste was extruded in 1/16'' asymmetric
quadrilobe shape, and dried at 250.degree. F. (121.degree. C.)
overnight. The dried extrudates were calcined at 1100.degree. F.
(593.degree. C.) for 1 hour with purging excess dry air, and cooled
down to room temperature.
[0095] Impregnation of Ni and W was done using a solution
containing ammonium metatungstate and nickel nitrate in
concentrations equal to the target metal loadings of 4 wt. % NiO
and 28 wt. % WO.sub.3 based on the bulk dry weight of the finished
catalyst. The total volume of the solution matched the 103% water
pore volume of the base extrudate sample (incipient wetness
hydroprocessing catalyst). The metal solution was added to the base
extrudates gradually while tumbling the extrudates. When the
solution addition was completed, the soaked extrudates were aged
for 2 hours. Then the extrudates were dried at 250.degree. F.
(121.degree. C.) overnight. The dried extrudates were calcined at
842.degree. F. (450.degree. C.) for 1 hour with purging excess dry
air, and cooled down to room temperature. This catalyst is named
Catalyst A and its physical properties are summarized in Table
3.
Example 2
Catalyst B--Modified Hydrocracking Catalyst
[0096] A modified Ni/W hydrocracking catalyst was prepared using
extrudates prepared with the same formulation as that for Catalyst
A. Impregnation of Ni and W was done using a solution containing
ammonium metatungstate and nickel nitrate in concentrations equal
to the target metal loadings of 4 wt. % NiO and 28 wt. % WO.sub.3
based on the bulk dry weight of the finished catalyst. 2-Hydroxy
1,2,3-propanetricarboxylic (used as a modifying agent), in an
amount equal to 10 wt. % of the bulk dry weight of the finished
catalyst, was added to the Ni/W solution. The solution was heated
to above 120.degree. F. (49.degree. C.) to ensure a completed
dissolved (clear) solution. The total volume of the metal solution
matched the 103% water pore volume of the base extrudates
(incipient wetness hydroprocessing catalyst). The metal solution
was added to the base extrudates gradually while tumbling the
extrudates. When the solution addition was completed, the soaked
extrudates were aged for 2 hours. Then the extrudates were dried at
400.degree. F. (205.degree. C.) for 2 hour with purging excess dry
air, and cooled down to room temperature.
Example 3
Catalyst C--Modified Hydrocracking Catalyst
[0097] Catalyst C was prepared by further calcination of a sampling
of Catalyst B at 842.degree. F. (450.degree. C.) for 1 hour.
Example 4
Catalyst D--Modified Hydrocracking Catalyst
[0098] Catalyst D was prepared per following procedure: 55 parts
silica-alumina powder, 25 parts pseudo boehmite alumina powder, and
20 parts of zeolite Y were mixed well. To the mix, a diluted
HNO.sub.3 acid (1 wt. %) solution was added to form an extrudable
paste. The paste was extruded in 1/16'' asymmetric quadrilobe, and
dried at 250.degree. F. (121.degree. C.) overnight. The dried
extrudates were calcined at 1100.degree. F. (593.degree. C.) for 1
hour with purging excess dry air, and cooled down to room
temperature.
[0099] Impregnation of Ni and W was done using a solution
containing ammonium metatungstate and nickel nitrate in
concentrations equal to the target metal loadings of 4 wt. % NiO
and 28 wt. % WO.sub.3 based on the bulk dry weight of the finished
catalyst. 2-Hydroxy 1,2,3-propanetricarboxylic (used as a modifying
agent), in an amount equal to 10 wt. % of the bulk dry weight of
the finished catalyst, was added to the Ni/W solution. The solution
was heated to above 120.degree. F. (49.degree. C.) to ensure a
clear solution. The total volume of the metal solution matched the
103% water pore volume of the base extrudates (incipient wetness
hydroprocessing catalyst). The metal solution was added to the base
extrudates gradually while tumbling the extrudates. When the
solution addition was completed, the soaked extrudates were aged
for 2 hours. Then the extrudates were dried at 400.degree. F.
(205.degree. C.) for 2 hour with purging excess dry air, and cooled
down to room temperature.
Example 5
Catalyst E--Modified Hydrocracking Catalyst
[0100] Catalyst E was prepared by further calcination of a sampling
of Catalyst D at 842.degree. F. (450.degree. C.) for 1 hour.
Example 6
Catalyst F--Modified Hydrocracking Catalyst
[0101] Catalyst F was prepared per following procedure: 69 parts
silica-alumina powder and 31 parts pseudo boehmite alumina powder
were mixed well. To the mix, a diluted HNO.sub.3 acid (1 wt. %)
solution was added to form an extrudable paste. The paste was
extruded in 1/16'' asymmetric quadrilobe, and dried at 250.degree.
F. (121.degree. C.) overnight. The dried extrudates were calcined
at 1100.degree. F. (593.degree. C.) for 1 hour with purging excess
dry air, and cooled down to room temperature.
[0102] Impregnation of Ni and W was done using a solution
containing ammonium metatungstate and nickel nitrate in
concentrations equal to the target metal loadings of 4 wt. % NiO
and 28 wt. % WO.sub.3 based on the bulk dry weight of the finished
catalyst. 2-Hydroxy 1,2,3-propanetricarboxylic (used as a modifying
agent), in an amount equal to 10 wt. % of the bulk dry weight of
the finished catalyst, was added to the Ni/W solution. The solution
was heated to above 120.degree. F. (49.degree. C.) to ensure a
clear solution. The total volume of the metal solution matched the
103% water pore volume of the base extrudates (incipient wetness
hydroprocessing catalyst). The metal solution was added to the base
extrudates gradually while tumbling the extrudates. When the
solution addition was completed, the soaked extrudates were aged
for 2 hours. Then the extrudates were dried at 400.degree. F.
(205.degree. C.) for 2 hour with purging excess dry air, and cooled
down to room temperature.
Example 7
Catalyst G--Modified Hydrocracking Catalyst
[0103] Catalyst G was prepared by further calcination of a sampling
of Catalyst F at 842.degree. F. (450.degree. C.) for 1 hour.
TABLE-US-00003 TABLE 3 CATALYST A B C D E F G Base Zeolite, wt. % 8
8 8 20 20 0 0 Silica Alumina, wt. % 67 67 67 55 55 69 69 Alumina,
wt. % 25 25 25 25 25 31 31 Porosity by N.sub.2 uptake Surface area,
m.sup.2/g 413 413 413 451 451 398 398 Mean mesopore diameter, .ANG.
90 90 90 80 80 94 94 Total pore volume, cc/g 0.69 0.69 0.69 0.67
0.67 0.69 0.69 CI test n-C.sub.6 conversion, wt. % 1.3 1.3 1.3 2.0
2.0 0.4 0.4 i-C.sub.6 conversion % 7.0 7.0 7.0 8.5 8.5 3.6 3.6
Finished Catalysts Metal content, wt. % NiO, wt. % 4 4 4 4
WO.sub.3, wt. % 28 28 28 28 Porosity by N.sub.2 uptake Surface
area, m.sup.2/g 231 243 314 235 Mean mesopore diameter, .ANG. 89 98
71 112 Micropore pore volume, cc/g 0.0059 0.0096 -- Total pore
volume, cc/g 0.40 0.42 0.41 0.44
Example 8
Hydrocracking Performance
[0104] A variety of feeds were used to evaluate the hydrocracking
performances of the catalysts. In each test, the catalyst was
subjected to the following process conditions for feed 1: 2300 PSIG
total pressure (2100 PSIA H.sub.2 at the reactor inlet), 5000 SCFB
H.sub.2, 1.0 LHSV, 60 LV % per pass conversion. For feed 2, the
testing conditions were: 1000 psig total pressure (900 psia H.sub.2
at the reactor inlet), 5000 scfb H.sub.2, 1.0 LHSV, 65 LV % per
pass conversion. Table 4 summarizes the physical properties of two
feeds used in the tests. Feed 1 is a hydrotreated VGO comprising
high concentrations of polycyclic aromatics. Feed 2 is a FT wax
generated from a GTL process.
TABLE-US-00004 TABLE 4 Feed 1 Feed 2 API Gravity 33.4 40.4 Sulfur,
ppm wt. 14.3 <2 Nitrogen, ppm wt. 0.5 7.9 Oxygen, wt. % 0 0.7
PCI 333 -- Components Paraffins, LV % 25.5 100 Naphthenes, LV %
66.5 0 Aromatics, LV % 8.0 0 ASTM D2887 SimDis, -.degree. F.
(.degree. C.) 0.5 wt. %/5 wt. % 771/819 437/572 (381/437) (225/300)
10 wt. %/30 wt. % 840/886 624/734 (449/474) (329/390) 50 wt. %/--
925/-- 809/-- (496)/-- (432)/-- 70 wt. %/90 wt. % 970/1045 898/1002
(521/563) (481/539) 95 wt. %/99.5 wt. % 1087/1213 1038/1094
(586/656) (559/590)
[0105] Tables 5 and 6 compare the hydrocracking performance over
catalysts prepared with and without a modifying agent.
TABLE-US-00005 TABLE 5 Hydrocracking Performance with Feed 1
Catalyst A Catalyst C Catalyst Activity, .degree. F. (.degree. C.)
Base Base No Loss Yields, wt. % C.sub.4- 4.7 4.0
C.sub.5-250.degree. F. (121.degree. C.) 19.0 17.7
C.sub.5-250-550.degree. F. (121-288.degree. C.) 54.0 53.4
C.sub.5-550-700.degree. F. (288-371.degree. C.) 23.7 26.1
TABLE-US-00006 TABLE 6 Hydrocracking Performance with Feed 2
Catalyst B Catalyst B* Catalyst D Base Base Base Catalyst Catalyst
A +1.degree. F. -13.degree. F. -16.degree. F. Activity, .degree. F.
(.degree. C.) Base (+0.55.degree. C.) (-7.2.degree. C.)
(-8.9.degree. C.) No Loss Yields, wt. % C.sub.4- 1.8 1.5 1.5 1.3
C.sub.5-290.degree. F. 15.4 12.7 13.4 13.4 (143.degree. C.)
C.sub.5-290-700.degree. F. 82.9 85.8 85.1 85.1 (143-371.degree. C.)
*with NH.sub.3 scrubbing
[0106] Catalyst C shows superior HCR performance over Catalyst A.
Catalyst C gave a diesel yield at least 2 wt % higher than base
case in expensive of low gas yield (C.sub.4-) and naphtha yield
(C.sub.5-250.degree. F./121.degree. C.). Catalyst C reduced the low
gas yield from 4.7 to 4.0 wt % and naphtha yield from 19.0 to 17.7
wt. % in comparison with A. Catalyst C made about 2.5 wt % more
heavy diesel (550-700.degree. F./288-371.degree. C.) than Catalyst
A with a very comparable jet yield (250-550.degree.
F./121-288.degree. C.). The use of
2-hydroxyl-1,2,3-propanetricarboxylic does not affect the catalyst
activity.
[0107] For Feed 2 (Table 6), both catalysts B and D showed higher
diesel yields than Catalyst A by at least 2 wt. % at the expensive
of low gas and naphtha, similar to the findings with the petroleum
feeds. Also observed was a significant improvement in catalyst
activity for Catalyst B and D by more than 10.degree. F.
(5.5.degree. C.) as compared to comparative Catalyst A.
[0108] Further, the modifying agent enhanced catalytic
hydrogenation activity with respect to saturate polycyclic
aromatics in the feed. FIG. 1 shows the polycyclic aromatics
concentration (measured by polycyclic aromatics index, PCI) in a
recycle liquid (e.g. >700.degree. F. (371.degree. C.) fraction)
for Feed 1 over Catalysts A and C. Their initial concentration in
the feed is also given for comparison. For Catalyst A, FIG. 1
clearly shows that polycyclic aromatics build up in the recycle
liquid linearly with time-on-stream over Catalyst A. For Catalyst
C, the PCI value in the recycle liquid was much lower than that in
the feed and in the recycle liquid with Catalyst A. Also, the PCI
value maintained at the same level with time on stream on Catalyst
C. This provides direct evidence for the improved hydrogenation
activity by the use of modifying agent. It is beneficial for
catalyst lifetime as the polycyclic aromatics are considered as
precursors of coke formation on catalyst surfaces blocking
catalytically active sites inaccessible to reactant molecules.
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