U.S. patent application number 15/085278 was filed with the patent office on 2016-09-15 for process for dechlorination of hydrocarbon streams and pyrolysis oils.
The applicant listed for this patent is Sabic Global Technologies, B.V.. Invention is credited to Mohammad JAVEED, Ravichander NARAYANASWAMY, Krishna Kumar RAMAMURTHY, Alexander STANISLAUS.
Application Number | 20160264880 15/085278 |
Document ID | / |
Family ID | 56879148 |
Filed Date | 2016-09-15 |
United States Patent
Application |
20160264880 |
Kind Code |
A1 |
NARAYANASWAMY; Ravichander ;
et al. |
September 15, 2016 |
Process for Dechlorination of Hydrocarbon Streams and Pyrolysis
Oils
Abstract
A process for dechlorination of a hydrocarbon stream includes
contacting the hydrocarbon stream with a hydroprocessing catalyst
in the presence of hydrogen to yield a hydrocarbon product which
meets steam cracker requirements for chloride content, and in
additional embodiments, requirements for olefin content.
Inventors: |
NARAYANASWAMY; Ravichander;
(Bengaluru, IN) ; RAMAMURTHY; Krishna Kumar;
(Bengaluru, IN) ; STANISLAUS; Alexander;
(Bangalore, IN) ; JAVEED; Mohammad; (Bengaluru,
IN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Sabic Global Technologies, B.V. |
BERGEN OP ZOOM |
|
NL |
|
|
Family ID: |
56879148 |
Appl. No.: |
15/085278 |
Filed: |
March 30, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
PCT/IB2016/051133 |
Mar 1, 2016 |
|
|
|
15085278 |
|
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62201655 |
Aug 6, 2015 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C10G 1/10 20130101; C10G
25/003 20130101; C10G 45/08 20130101; C10G 2300/202 20130101; C10G
69/06 20130101; C10G 9/36 20130101 |
International
Class: |
C10G 45/08 20060101
C10G045/08; C10G 69/06 20060101 C10G069/06 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 10, 2015 |
IN |
1163CHE2015 |
Claims
1. A process for dechlorination of a hydrocarbon stream comprising:
contacting the hydrocarbon stream with a hydroprocessing catalyst
in the presence of hydrogen to yield a hydrocarbon product, wherein
the hydrocarbon stream comprises one or more chloride compounds in
a concentration of 5 ppm or more based on a total weight of the
hydrocarbon stream; and recovering a treated hydrocarbon stream
from the hydrocarbon product, wherein the treated hydrocarbon
stream comprises the one or more chloride compounds in a
concentration of less than 5 ppm based on a total weight of the
treated hydrocarbon stream.
2. The process of claim 1, wherein the treated hydrocarbon stream
comprises the one or more chloride compounds in a concentration of
less than 1 ppm based on the total weight of the treated
hydrocarbon stream.
3. The process of claim 1, wherein the hydrocarbon stream comprises
the one or more chloride compounds in a concentration of greater
than 200 ppm based on a total weight of the hydrocarbon stream.
4. The process of claim 1, wherein the hydrocarbon stream further
comprises one or more olefins, wherein the treated hydrocarbon
stream further comprises the one or more olefins in a concentration
of less than 1 wt % based on the total weight of the treated
hydrocarbon stream.
5. The process of claim 4, wherein the one or more olefins are
present in the hydrocarbon stream in a concentration of 20 wt % or
more based on the total weight of the hydrocarbon stream.
6. The process of claim 1, wherein the hydrocarbon stream further
comprises paraffins.
7. The process of claim 6, wherein the hydrocarbon stream further
comprises one or more olefins, wherein the treated hydrocarbon
stream further comprises the paraffins and the one or more olefins,
wherein the one or more olefins of the treated hydrocarbon stream
are present in a concentration of less than 1 wt % based on the
total weight of the treated hydrocarbon stream.
8. The process of claim 1, wherein the hydrocarbon stream further
comprises one or more sulphides, wherein the one or more sulphides
of the hydrocarbon stream are present in an amount such that a
sulphur content of the hydrocarbon stream is about 0.5 wt % to
about 5 wt % based on the total weight of the hydrocarbon
stream.
9. The process of claim 1, wherein the hydroprocessing catalyst
comprises cobalt and molybdenum on an alumina support, nickel and
molybdenum on an alumina support, or nickel and molybdenum
sulphides, wherein contacting the hydrocarbon stream with the
hydroprocessing catalyst comprises: contacting one or more
sulphides contained in or added to the hydrocarbon stream with the
hydroprocessing catalyst, and wherein the one or more sulphides are
contained in or added to the hydrocarbon stream in an amount such
that a sulphur content of the hydrocarbon stream is about 2 wt %
based on the total weight of the hydrocarbon stream.
10. The process of claim 1, wherein the step of contacting is
performed at a temperature of 100.degree. C. to 450.degree. C.
11. The process of claim 1, wherein the step of contacting is
performed at a weight hourly space velocity of 0.1 to 10 hr.sup.-1,
at a hydrogen to hydrocarbon ratio of 10 to 3,000 NL/L, and at a
pressure of 1 to 200 barg.
12. The process of claim 1, wherein the treated hydrocarbon stream
comprises the one or more chloride compounds in a concentration of
less than 3 ppm based on a total weight of the treated hydrocarbon,
the process further comprising: feeding the treated hydrocarbon
stream to a steam cracker.
13. The process of claim 1, further comprising: blending the
treated hydrocarbon stream with a non-chlorinated hydrocarbon
stream to yield a blended hydrocarbon stream comprising the one or
more chloride compounds in a concentration of less than 3 ppm based
on a total weight of the blended hydrocarbon stream; and feeding
the blended hydrocarbon stream to a steam cracker.
14. The process of claim 1, wherein recovering a treated
hydrocarbon stream from the hydrocarbon product comprises:
separating a treated product from a chlorine-containing gas in a
separator; and flowing the treated product in the treated
hydrocarbon stream from the separator.
15. The process of claim 1, wherein no hydrogen halides and no
halogenated organic compounds are recycled to the hydroprocessing
reactor.
16. The process of claim 1, wherein the step of contacting is
performed without use of chlorine sorbents.
17. The process of claim 1, wherein the step of contacting is
performed without the presence of Na.sub.2CO.sub.3 in an effective
amount to function as a dechlorinating agent.
18. The process of claim 1, wherein the hydroprocessing reactor is
configured to operate in the slurry phase.
19. The process of claim 1, wherein the step of contacting includes
simultaneous dechlorination and hydrogenation of the hydrocarbon
stream such that the treated hydrocarbon stream comprises the one
or more chloride compounds in a concentration less than 1 ppm and
one or more olefins in a concentration less than 1 wt % based on
the total weight of the treated hydrocarbon stream.
20. The process of claim 1, wherein the one or more chloride
compounds include 1-chlorohexane, 2-chloropentane,
3-chloro-3-methyl pentane, (2-chloroethyl) benzene, chlorobenzene,
or combinations thereof.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a continuation of and claims
priority to International Application No. PCT/IB2016/051133 filed
Mar. 1, 2016, entitled "Process for Dechlorination of Hydrocarbon
Streams and Pyrolysis Oils," which claims priority to U.S.
Provisional Application No. 62/201,655 filed on Aug. 6, 2015,
entitled "Process for Dechlorination of Hydrocarbon Streams and
Pyrolysis Oils," and Indian Provisional Application No.
1163/CHE/2015 filed Mar. 10, 2015 entitled "Process for
Dechlorination of Hydrocarbon Streams and Pyrolysis Oils," which
applications are incorporated by reference herein in their
entirety.
TECHNICAL FIELD
[0002] This disclosure relates the treatment of hydrocarbon streams
via processes which include dechlorination.
BACKGROUND
[0003] Waste plastics contain polyvinylchloride (PVC). Through a
pyrolysis process, waste plastics can be converted to gas and
liquid products. These liquid products contain paraffins,
i-paraffins (iso-paraffins), olefins, naphthenes, and aromatic
components along with organic chlorides in concentrations of
hundreds of ppm. However, the liquid products of a pyrolysis
process (pyrolysis oils) are off-spec for use as a feedstock for
steam crackers because steam cracker feed specifications require
chloride levels less than 3 ppm and olefin content less than 1 wt
%.
SUMMARY
[0004] A process for dechlorination of a hydrocarbon stream
comprising contacting the hydrocarbon stream with a hydroprocessing
catalyst in the presence of hydrogen to yield a hydrocarbon
product, wherein the hydrocarbon stream comprises one or more
chloride compounds in a concentration of 5 ppm or more based on a
total weight of the hydrocarbon stream, and recovering a treated
hydrocarbon stream from the hydrocarbon product, wherein the
treated hydrocarbon stream comprises the one or more chloride
compounds in a concentration of less than 5 ppm based on a total
weight of the treated hydrocarbon stream.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 illustrates a hydroprocessing system which
dechlorinates chloride compounds, and in embodiments, additionally
hydrogenates olefins contained in a hydrocarbon stream to levels
suitable for introduction to a steam cracker.
[0006] FIG. 2 is a graph of a staged catalyst sulphiding protocol,
showing temperature versus time.
DETAILED DESCRIPTION
[0007] Other than in the operating examples or where otherwise
indicated, all numbers or expressions referring to quantities of
ingredients, reaction conditions, and the like, used in the
specification and claims are to be understood as modified in all
instances by the term "about." Various numerical ranges are
disclosed herein. Because these ranges are continuous, they include
every value between the minimum and maximum values. The endpoints
of all ranges reciting the same characteristic or component are
independently combinable and inclusive of the recited endpoint.
Unless expressly indicated otherwise, the various numerical ranges
specified in this application are approximations. The endpoints of
all ranges directed to the same component or property are inclusive
of the endpoint and independently combinable. The term "X or more"
means that the named component is present in an amount of the value
X, and values which are more than X.
[0008] The terms "a," "an," and "the" do not denote a limitation of
quantity, but rather denote the presence of at least one of the
referenced item. As used herein the singular forms "a," "an," and
"the" include plural referents.
[0009] As used herein, "combinations thereof" is inclusive of one
or more of the recited elements, optionally together with a like
element not recited, e.g., inclusive of a combination of one or
more of the named components, optionally with one or more other
components not specifically named that have essentially the same
function. As used herein, the term "combination" is inclusive of
blends, mixtures, alloys, reaction products, and the like.
[0010] Reference throughout the specification to "an embodiment,"
"embodiments," "another embodiment," "other embodiments,"
"alternative embodiments," "additional embodiments," "some
embodiments," and so forth (e.g., the use of "additionally" and/or
"alternatively" in the context of describing one or more
embodiments), means that a particular element (e.g., feature,
structure, property, and/or characteristic) described in connection
with the embodiment is included in at least an embodiment described
herein, and may or may not be present in other embodiments. In
addition, it is to be understood that the described element(s) can
be combined in any suitable manner in the various embodiments.
[0011] Disclosed herein are embodiments of a process for
dechlorination of a hydrocarbon stream which include contacting the
hydrocarbon stream with a hydroprocessing catalyst in the presence
of hydrogen to yield a hydrocarbon product. Embodiments of the
process include recovering a treated hydrocarbon stream from the
hydrocarbon product, where the treated hydrocarbon stream has a
reduced concentration of chloride compounds compared to the
concentration of chloride compounds in the hydrocarbon feed
stream.
[0012] Embodiments of the process are described in more detail with
reference to FIG. 1. FIG. 1 illustrates a hydroprocessing which
dechlorinates chloride compounds, and in embodiments, additionally
hydrogenates olefins contained in a hydrocarbon stream 1 to levels
suitable for introduction to a steam cracker 30. The system 100
includes a hydroprocessing reactor 10, a separator 20, and a steam
cracker 30. The hydrocarbon stream 1 feeds to the hydroprocessing
reactor 10, and the reaction product effluent flows from the
hydroprocessing reactor 10 in the hydrocarbon product stream 2 to
the separator 20. In separator 20, a treated product (e.g., in gas
or liquid form) is recovered from the hydrocarbon product stream 2
and flows from the separator 20 via treated hydrocarbon stream 4,
with one or more sulphur-containing gases and/or
chlorine-containing gases flowing from the separator 20 in stream
3. Embodiments of the disclosure contemplate a second
hydroprocessing reactor and a second separator may be placed in
between separator 20 and treated hydrocarbon stream 4. The treated
product flowing from the separator 20, in such embodiments, may
contain residual sulphur, and the second hydroprocessing
reactor/second separator combination may treat the treated product
flowing from the separator 20 to completely remove the sulphur such
that a second treated product flowing in the treated hydrocarbon
stream 4 from the second separator contains less than 200, 100, 90,
80, 70, 60, 50, 40, 30, 20, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0.5, 0.1
ppmw S based on total weight of the treated hydrocarbon stream
4.
[0013] The treated product in the treated hydrocarbon stream 4 may
flow directly (e.g., without any separations or fractionations of
the treated hydrocarbon stream 4) or via blended hydrocarbon stream
4' (e.g., without any separations or fractionations of the treated
hydrocarbon stream 4 and blended hydrocarbon stream 4') to a steam
cracker 30, from which high value products flow in stream 6.
[0014] The hydrocarbon stream 1 generally includes one or more
hydrocarbons and one or more chloride compounds. In embodiments,
the hydrocarbon stream 1 may additionally include one or more
sulphides, hydrogen, or combinations thereof. The hydrocarbon
stream 1 is generally in a liquid phase. A hydrogen (H.sub.2)
stream can be added to hydrocarbon stream 1 before entering the
hydroprocessing reactor 10. Optionally, a H.sub.2 stream is
additionally added in between various catalyst beds in a multi-bed
arrangement in the hydroprocessing reactor 10 to enrich the reactor
environment with H.sub.2.
[0015] The hydrocarbon stream 1 may be a stream from an upstream
process, such as a pyrolysis process, which contains one or more
chloride compounds, and optionally, also one or more sulphides, for
example, from the pyrolysis of waste plastics. In an embodiment
wherein the stream from the upstream process does not contain the
one or more sulphides, the hydrocarbon stream 1 may be doped with
the one or more sulphides, via a doping stream 7.
[0016] Examples of the one or more hydrocarbons which may be
included in the hydrocarbon stream 1 include paraffins (n-paraffin,
i-paraffin, or both), olefins, naphthenes, aromatic hydrocarbons,
or combinations thereof. When the one or more hydrocarbons includes
all the listed hydrocarbons, the group of hydrocarbons may be
collectively referred to as a PONA feed (paraffin, olefin,
naphthene, aromatics) or PIONA feed (n-paraffin, i-paraffin,
olefin, naphthene, aromatics). A particular embodiment of the
hydrocarbon stream 1 is a plastic pyrolysis oil, discussed in more
detail below.
[0017] Any paraffin may be included in the hydrocarbon stream 1.
Examples of paraffins which may be included in the hydrocarbon
stream 1 include, but are not limited to, C.sub.1 to C.sub.22
n-paraffins and i-paraffins. In an embodiment, the concentration of
paraffins in the hydrocarbon stream 1 may be less than 10 wt %
based on the total weight of the hydrocarbon stream 1.
Alternatively, the concentration of paraffins in the hydrocarbon
stream 1 may be 10 wt %, 20 wt %, 30 wt %, 40 wt %, 50 wt %, 60 wt
%, or more based on the total weight of the hydrocarbon stream 1.
While embodiments include paraffins of carbon numbers up to 22, the
disclosure is not limited to carbon number 22 as an upper end-point
of the suitable range of paraffins, and the paraffins can include
higher carbon numbers, e.g., 23, 24, 25, 26, 27, 28, 29, 30, 31,
32, 33, 34, 35, 36, 37, 38, 39, 40, and higher.
[0018] Any olefin may be included in the hydrocarbon stream 1.
Examples of olefins which may be included in hydrocarbon stream 1
include, but are not limited to, C.sub.2 to C.sub.10 olefins and
combinations thereof. In an embodiment, the concentration of
olefins in the hydrocarbon stream 1 may be less than 10 wt % based
on the total weight of the hydrocarbon stream 1. Alternatively, the
concentration of olefins in the hydrocarbon stream 1 may be 10 wt
%, 20 wt %, 30 wt %, 40 wt % or more based on the total weight of
the hydrocarbon stream 1. While embodiments include olefins of
carbon numbers up to 10, the disclosure is not limited to carbon
number 10 as an upper end-point of the suitable range of olefins,
and the olefins can include higher carbon numbers, e.g., 11, 12,
13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29,
30, and higher.
[0019] In an embodiment, the hydrocarbon stream 1 comprises no
olefins.
[0020] Any naphthene may be included in the hydrocarbon stream 1.
Examples of naphthenes include, but are not limited to,
cyclopentane, cyclohexane, cycloheptane, and cyclooctane. In an
embodiment, the concentration of naphthenes in the hydrocarbon
stream 1 may be less than 10 wt % based on the total weight of the
hydrocarbon stream 1. Alternatively, the concentration of
naphthenes in the hydrocarbon stream 1 may be 10 wt %, 20 wt %, 30
wt %, 40 wt % or more based on the total weight of the hydrocarbon
stream 1. While embodiments include naphthenes of carbon numbers up
to 8, the disclosure is not limited to carbon number 8 as an upper
end-point of the suitable range of naphthenes, and the naphthenes
can include higher carbon numbers, e.g., 9, 10, 11, 12, 13, 14, 15,
16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, and
higher.
[0021] Any aromatic hydrocarbon may be included in the hydrocarbon
stream 1. Aromatic hydrocarbons suitable for use in the hydrocarbon
stream 1 include, but are not limited to, benzene, toluene,
xylenes, ethyl benzene, or combinations thereof. In an embodiment,
the concentration of aromatic hydrocarbons in the hydrocarbon
stream 1 may be less than 10 wt % based on the total weight of the
hydrocarbon stream 1. Alternatively, the concentration of aromatic
hydrocarbons in the hydrocarbon stream 1 may be 10 wt %, 20 wt %,
30 wt %, 40 wt % or more based on the total weight of the
hydrocarbon stream 1. While embodiments include aromatic
hydrocarbons of carbon numbers up to 8, the disclosure is not
limited to carbon number 8 as an upper end-point of the suitable
range of aromatic hydrocarbons, and the aromatic hydrocarbons can
include higher carbon numbers, e.g., 9, 10, 11, 12, 13, 14, 15, 16,
17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, and higher.
In an embodiment, the aromatic hydrocarbons carbon number is as
high as 22.
[0022] In an embodiment, the hydrocarbon stream 1 comprises no
aromatic hydrocarbons.
[0023] Chloride compounds which may be included in the hydrocarbon
stream 1 include, but are not limited to, aliphatic
chlorine-containing hydrocarbons, aromatic chlorine-containing
hydrocarbons, and other chlorine-containing hydrocarbons. Examples
of chlorine-containing hydrocarbons include, but are not limited
to, 1-chlorohexane (C.sub.6H.sub.13Cl), 2-chloropentane
(C.sub.5H.sub.11Cl), 3-chloro-3-methyl pentane (C.sub.6H.sub.13Cl),
(2-chloroethyl) benzene (C.sub.8H.sub.9Cl), chlorobenzene
(C.sub.6H.sub.5Cl), or combinations thereof. The concentration of
chloride compounds in the hydrocarbon stream 1 may be 5 ppm, 6 ppm,
7 ppm, 8 ppm, 9 ppm, 10 ppm, 15 ppm, 20 ppm, 30 ppm, 40 ppm, 50
ppm, 100 ppm, 200 ppm, 300 ppm, 400 ppm, 500 ppm, 600 ppm, 700 ppm,
800 ppm, 900 ppm, 1,000 ppm, 1,100 ppm, 1,200 ppm, 1,300 ppm, 1,400
ppm, 1,500 ppm, 1,600 ppm, 1,700 ppm, 1,800 ppm, 1,900 ppm, 2,000
ppm or more based on the total weight of the hydrocarbon stream
1.
[0024] Sulphides which may be included in the hydrocarbon stream 1
include sulphur-containing compounds. For example, a sulphiding
agent such as dimethyl disulphide (C.sub.2H.sub.6S.sub.2), dimethyl
sulphide (C.sub.2H.sub.6S), mercaptans (R--SH), carbon disulphide
(CS.sub.2), hydrogen sulphide (H.sub.2S), or combinations thereof
may be used as the sulphide in the hydrocarbon stream 1.
[0025] In an embodiment, one or more sulphides (e.g., dimethyl
disulphide (C.sub.2H.sub.6S.sub.2), dimethyl sulphide
(C.sub.2H.sub.6S), mercaptans (R--SH), carbon disulphide
(CS.sub.2), hydrogen sulphide (H.sub.2S), or combinations thereof)
are added to the hydrocarbon stream 1 (e.g., the hydrocarbon stream
1 is "doped" with one or more sulphides), for example, via a doping
stream 7, before the hydrocarbon stream 1 is introduced to the
hydroprocessing reactor 10. In such embodiments, the one or more
sulphides are added to the hydrocarbon stream 1 in an amount such
that a sulphur content of the hydrocarbon stream 1, after sulphide
addition, is about 0.5 wt %, 1 wt %, 1.5 wt %, 2 wt %, 2.5 wt %, 3
wt %, 3.5 wt %, 4 wt %, 4.5 wt %, 5 wt % or more based on the total
weight of the hydrocarbon stream 1. In embodiments, the doping
stream 7 may include components tailored for doping such as
hexadecane and dimethyl disulphide; alternatively, the doping
stream 7 may be a heavier oil (e.g., naphtha, diesel, or both)
which already contains sulphide compounds (or to which sulphides
are doped to achieve the sulphur content disclosed herein) and
which is blended with the hydrocarbon stream 1 to achieve the
sulphur content described above.
[0026] In alternative embodiments, one or more sulphides are
present in the hydrocarbon stream as a result of upstream
processing from which the hydrocarbon stream 1 flows. In such
embodiments, the hydrocarbon stream 1 may contain one or more
sulphides in an amount such that a sulphur content of the
hydrocarbon stream 1, without sulphide doping, is about 0.5 wt %, 1
wt %, 1.5 wt %, 2 wt %, 2.5 wt %, 3 wt %, 3.5 wt %, 4 wt %, 4.5 wt
%, 5 wt % or more based on the total weight of the hydrocarbon
stream 1.
[0027] In yet other embodiments, the hydrocarbon stream 1 may
contain one or more sulphides in an amount insufficient for
sulphiding (e.g., less than 5,000, 4,000, 3,000, 2,000, 1,000, 900,
800, 700, 600, 500, 400, 300, 200, 100, 90, 80, 70, 60, 50, 40, 30,
20, 10, 5, or 1 ppm) the hydroprocessing catalyst contained in the
hydroprocessing reactor 10 (the catalyst is discussed in more
detail below), and doping stream 7 is utilized to raise the
concentration of the one or more sulphides in the hydrocarbon
stream 1 to such that a sulphur content of the hydrocarbon stream
1, after sulphide addition, is about 0.5 wt %, 1 wt %, 1.5 wt %, 2
wt %, 2.5 wt %, 3 wt %, 3.5 wt %, 4 wt %, 4.5 wt %, 5 wt % or more
based on the total weight of the hydrocarbon stream 1.
[0028] In an embodiment, the sulphur content of the hydrocarbon
stream 1, after sulphide addition using doping stream 7, is up to
about 3 wt % based on the total weight of the hydrocarbon stream 1.
In another embodiment, the sulphur content of the hydrocarbon
stream 1, without sulphide addition using doping stream 7, is up to
about 3 wt % based on the total weight of the hydrocarbon stream
1.
[0029] In embodiments, the hydrocarbon stream 1 may be one or more
plastic pyrolysis oils which contain any of the paraffins,
i-paraffins, olefins, naphthenes, aromatic hydrocarbons, chloride
compounds, sulphides, or combinations thereof as disclosed herein.
The one or more plastic pyrolysis oils may be obtained from
pyrolysis of waste plastics (for example, from a high severity
process as disclosed in U.S. Pat. No. 8,895,790, which is
incorporated by reference in its entirety, or from any low
temperature severity pyrolysis process known in the art with the
aid of this disclosure).
[0030] Other streams which may comprise at least a portion of the
hydrocarbon stream 1 include a reformate stream from catalytic
naphtha reformer, tire pyrolysis oil, and any other chloride
containing hydrocarbon stream.
[0031] In embodiments, the hydrocarbon stream 1 may be one or more
pyrolysis oils as described above which is blended with a heavier
oil (e.g., a naphtha or diesel, via doping stream 7). In such
embodiments, blending the treated hydrocarbon stream 4 with a
non-chlorinated stream 5 as described for embodiments below may
additionally occur; alternatively, the subsequent blending may not
occur.
[0032] The hydroprocessing reactor 10 is configured to
dechlorinate, and in some embodiments, additionally hydrogenate
components of the hydrocarbon stream 1 fed to the hydroprocessing
reactor 10. In the hydroprocessing reactor 10, the hydrocarbon
stream 1 is contacted with the hydroprocessing catalyst in the
presence of hydrogen to yield a hydrocarbon product in stream 2. It
is contemplated the hydrocarbon stream 1 may be contacted with the
hydroprocessing catalyst in upward flow, downward flow, radial
flow, or combinations thereof, with or without a staged addition of
hydrocarbon stream 1, doping stream 7, a H.sub.2 stream, or
combinations thereof. It is further contemplated the components of
the hydrocarbon stream 1 may be in the liquid phase, a liquid-vapor
phase, or a vapor phase while in the hydroprocessing reactor
10.
[0033] The hydroprocessing reactor 10 may facilitate any reaction
of the components of the hydrocarbon stream 1 in the presence of,
or with, hydrogen. Reactions may occur as the addition of hydrogen
atoms to double bonds of unsaturated molecules (e.g., olefins,
aromatic compounds), resulting in saturated molecules (e.g.,
paraffins, i-paraffins, naphthenes). Additionally or alternatively,
reactions in the hydroprocessing reactor 10 may cause a rupture of
a bond of an organic compound, with a subsequent reaction and/or
replacement of a heteroatom with hydrogen. Examples of reactions
which may occur in the hydroprocessing reactor 10 include, but are
not limited to, the hydrogenation of olefins, removal of
heteroatoms from heteroatom-containing hydrocarbons (e.g.,
dechlorination), conversion of one or more aromatics to one or more
cycloparaffins, isomerization of one or more normal paraffins to
one or more i-paraffins, selective ring opening of one or more
cycloparaffins to one or more i-paraffins, or combinations
thereof.
[0034] In embodiments, the hydroprocessing reactor 10 may be any
vessel configured to contain the hydroprocessing catalyst disclosed
herein. The vessel may be configured for gas phase, liquid phase,
vapor-liquid phase, or slurry phase operation. The hydroprocessing
reactor 10 may include one or more beds of the hydroprocessing
catalyst in fixed bed, fluidized bed, moving bed, ebullated bed,
slurry bed, or combinations thereof, configuration. The
hydroprocessing reactor 10 may be operated adiabatically,
isothermally, nonadiabatically, non-isothermally, or combinations
thereof. The reactions of this disclosure may be carried out in a
single stage or in multiple stages. For example, the
hydroprocessing reactor 10 can be two reactor vessels fluidly
connected in series, each having one or more catalyst beds of the
hydroprocessing catalyst. Alternatively, two or more stages for
hydroprocessing may be contained in a single reactor vessel. In
embodiments having multiple stages, the first stage may
dechlorinate and hydrogenate components of the hydrocarbon stream 1
to yield a first hydrocarbon product having a first level of
chloride compounds and olefins. The first hydrocarbon product may
flow from the first stage to the second stage, where other
components of the first hydrocarbon product are dechlorinated and
hydrogenated to yield a second hydrocarbon product stream (stream 2
in FIG. 1) having a second level of chloride compounds and olefins.
The second hydrocarbon product stream may then be treated as
described herein for stream 2.
[0035] In an embodiment, the hydroprocessing reactor 10 may
comprise one or more vessels.
[0036] In embodiments of a single vessel or multiple vessels, the
sulphur present in the hydrocarbon stream 1 is removed as H.sub.2S
to provide a reduced level of sulphur acceptable for downstream
processing in steam crackers and refinery units.
[0037] In an embodiment, hydrogen may feed to the hydroprocessing
reactor 10 in stream 8. The rate of hydrogen addition to the
hydroprocessing reactor 10 is generally sufficient to achieve the
hydrogen-to-hydrocarbon ratios disclosed herein.
[0038] The disclosed hydroprocessing reactor 10 may operate at
various process conditions. For example, contacting the hydrocarbon
stream 1 with the hydroprocessing catalyst in the presence of
hydrogen may occur in the hydroprocessing reactor 10 at a
temperature of 100.degree. C. to 450.degree. C.; alternatively,
100.degree. C. to 350.degree. C.; or alternatively, 260.degree. C.
to 350.degree. C. Contacting the hydrocarbon stream 1 with the
hydroprocessing catalyst in the presence of hydrogen may occur in
the hydroprocessing reactor 10 at a pressure of 1 barg to 200 barg;
or alternatively, 20 barg to 60 barg. Contacting the hydrocarbon
stream 1 with the hydroprocessing catalyst in the presence of
hydrogen may occur in the hydroprocessing reactor 10 at a weight
hourly space velocity (WHSV) of between 0.1 hr.sup.-1 to 10
hr.sup.-1; or alternatively, 1 hr.sup.-1 to 3 hr.sup.-1. Contacting
the hydrocarbon stream 1 with the hydroprocessing catalyst in the
presence of hydrogen may occur in the hydroprocessing reactor 10 at
a hydrogen-to-hydrocarbon (H.sub.2/HC) flow ratio of 10 to 3,000
NL/L; or alternatively, 200 to 800 NL/L.
[0039] It is contemplated that dechlorination using the
hydroprocessing catalyst as described herein is performed in the
hydroprocessing reactor 10 without the use of chlorine sorbents,
without addition of Na.sub.2CO.sub.3 in an effective amount to
function as a dechlorinating agent, or both.
[0040] The hydroprocessing catalyst may be any catalyst used for
hydrogenation (e.g., saturation) of olefins and aromatic
hydrocarbons (e.g., a commercially available hydrotreating
catalyst). In an embodiment, the hydroprocessing catalyst is a
cobalt and molybdenum catalyst (Co--Mo catalyst) on an alumina
support. In other embodiments, the hydroprocessing catalyst is a
nickel and molybdenum catalyst (Ni--Mo catalyst) on an alumina
support or tungsten and molybdenum catalyst (W--Mo catalyst) on an
alumina support. Other catalyst embodiments may include platinum
and palladium catalyst (Pt--Pd catalyst) on an alumina support,
nickel sulphides suitable for slurry processing, molybdenum
sulphides suitable for slurry processing, nickel and molybdenum
sulphides, or combinations thereof.
[0041] In embodiments, the hydroprocessing catalyst is activated
and/or the activity is maintained by sulphiding the hydroprocessing
catalyst. For example, the hydroprocessing catalyst may be
sulphided (i.e., activated) and/or sulphiding (i.e., maintaining of
the catalyst activity) of the hydroprocessing catalyst may be
performed (e.g., maintaining the hydroprocessing catalyst in
sulphided form is accomplished) by continuously contacting the
hydrocarbon stream 1 containing one or more sulphides with the
hydroprocessing catalyst. The one or more sulphides may be included
in the hydrocarbon stream 1 in an amount such that the sulphur
content of the hydrocarbon stream 1 is about 0.5 wt %, 1 wt %, 1.5
wt %, 2 wt %, 2.5 wt %, 3 wt %, 3.5 wt %, 4 wt %, 4.5 wt %, or 5 wt
% based on the total weight of the hydrocarbon stream 1. In an
embodiment, the sulphur content of the hydrocarbon stream 1 is up
to about 3 wt % based on the total weight of the hydrocarbon stream
1.
[0042] Alternatively, the hydroprocessing catalyst may be sulphided
(i.e., activated) by contacting a catalyst activating stream 9
containing one or more sulphides with the hydroprocessing catalyst
for a period of time (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9 or more
hours) sufficient to activate the hydroprocessing catalyst (before
contacting the hydrocarbon stream 1 with the hydroprocessing
catalyst). In such embodiments, the catalyst activating stream 9
may include a hydrocarbon carrier for the one or more sulphides,
such as hexadecane. The one or more sulphides may be included in
the catalyst activating stream 9 in an amount such that the sulphur
content of the catalyst activating stream 9 is about 0.5 wt %, 1 wt
%, 1.5 wt %, 2 wt %, 2.5 wt %, 3 wt %, 3.5 wt %, 4 wt %, 4.5 wt %,
5 wt % or more based on the total weight of the catalyst activating
stream 9. In an embodiment, the sulphur content of the catalyst
activating stream 9 is up to about 3 wt % based on the total weight
of the catalyst activating stream 9. After the hydroprocessing
catalyst is activated with the catalyst activating stream 9, flow
of the catalyst activating stream 9 may be discontinued, and
sulphiding (i.e., maintaining catalyst activity) of the
hydroprocessing catalyst may be maintained (e.g., maintaining the
hydroprocessing catalyst in sulphided form is accomplished) by
continuously contacting the hydrocarbon stream 1 containing one or
more sulphides with the hydroprocessing catalyst. The one or more
sulphides may be included in the hydrocarbon stream 1 in an amount
such that the sulphur content of the hydrocarbon stream 1 is about
0.5 wt %, 1 wt %, 1.5 wt %, 2 wt %, 2.5 wt %, 3 wt %, 3.5 wt %, 4
wt %, 4.5 wt %, or 5 wt % based on the total weight of the
hydrocarbon stream 1. In an embodiment, the sulphur content of the
hydrocarbon stream 1 is up to about 3 wt % based on the total
weight of the hydrocarbon stream 1.
[0043] In embodiments, catalyst activity is also maintained by
chloriding the hydroprocessing catalyst. The hydroprocessing
catalyst is chlorided using the one or more chloride compounds
provided to the hydroprocessing catalyst by the hydrocarbon stream
1. The one or more chloride compounds which contribute to
acidification of the hydroprocessing catalyst may be included in
the hydrocarbon stream 1 in concentrations disclosed herein.
[0044] Due to hydrogenation reactions in the hydroprocessing
reactor 10, in embodiments, the hydrocarbon product stream 2 may
contain one or more olefins in a concentration of less than 1 wt %
based on the total weight of the hydrocarbon product stream 2. It
is also contemplated that the concentration of aromatic
hydrocarbons in the hydrocarbon product stream 2 is less than the
concentration of aromatic hydrocarbons in the hydrocarbon stream 1
due to hydrogenation of at least a portion of the aromatic
hydrocarbons in the hydroprocessing reactor 10. For example,
aromatic hydrocarbons may be present in the hydrocarbon product
stream 2 in a concentration of less than 10, 9, 8, 7, 6, 5, 4, 3,
2, or 1 wt % based on the total weight of the hydrocarbon product
stream 2.
[0045] The reaction product flows as effluent from the
hydroprocessing reactor 10 in the hydrocarbon product stream 2 to
the separator 20. Separator 20 may be any vessel which can recover
a treated hydrocarbon stream 4 from the hydrocarbon product 2 which
is fed to the separator 20. In embodiments, the treated hydrocarbon
stream 4 may be recovered by separating a treated product (e.g.,
liquid product or gas product) from sulphur and chlorine-containing
gas in the separator 20, and by flowing the treated product in the
treated hydrocarbon stream 4 from the separator 20.
[0046] In an embodiment, the separator 20 is a condenser which
operates at conditions which condense a portion of the hydrocarbon
product stream 2 into the treated product (e.g., liquid product or
treated liquid product) while leaving sulphur and
chlorine-containing compounds in the gas phase. The treated liquid
product flows from the separator 20 in treated hydrocarbon stream
4, and the sulphur and chlorine-containing gas flows from the
separator 20 via stream 3.
[0047] In another embodiment, the separator 20 is a scrubbing unit
containing a caustic solution (e.g., a solution of sodium hydroxide
in water) which removes (e.g., via reaction, adsorption,
absorption, or combinations thereof) sulphur and
chlorine-containing gases from the hydrocarbon product stream 2 to
yield the treated product (e.g., gas product or treated gas
product) which flows from the separator 20 via treated hydrocarbon
stream 4 while the sulphur and chlorine-containing compounds in the
gas phase flow from the separator 20 via stream 3.
[0048] In yet another embodiment, the separator 20 is a condenser
in communication with a scrubbing unit containing a caustic
solution. As described above, the condenser may operate at
conditions which condense a portion of the hydrocarbon product
stream 2 into the mid-treated product (e.g., liquid product or
treated liquid product) while leaving sulphur and
chlorine-containing compounds in the gas phase. The mid-treated
liquid product flows from the condenser and experiences a pressure
reduction (e.g., via a valve or other pressure reducing device
known in the art with the aid of this disclosure) which creates an
effluent gas which flows from the scrubbing unit, leaving the
treated product flowing in treated hydrocarbon stream 4. Sulphur
and chlorine-containing compounds flow from the separator 20 in
stream 3.
[0049] In embodiments disclosed herein, no hydrogen halides and no
halogenated organic compounds are recycled to the hydroprocessing
reactor 10.
[0050] In embodiments, the treated hydrocarbon stream 4 includes
one or more chloride compounds in a concentration of less than 5
ppm, 4 ppm, 3 ppm, 2 ppm, 1 ppm, or 0.5 ppm based on a total weight
of the treated hydrocarbon stream 4. It is contemplated that the
one or more chloride compounds in the treated hydrocarbon stream 4
may be the same as some or all of the one or more chloride
compounds in the hydrocarbon stream 1; alternatively, it is
contemplated that only some of the one or more chloride compounds
in the treated hydrocarbon stream 4 are the same as only some of
the one or more chloride compounds in the hydrocarbon stream 1;
alternatively, it is contemplated that none of the one or more
chloride compounds in the treated hydrocarbon stream 4 are the same
as the one or more chloride compounds in the hydrocarbon stream
1.
[0051] In additional embodiments, the treated hydrocarbon stream 4
includes the one or more olefins in a concentration which is less
than a concentration of the one or more olefins in the hydrocarbon
stream 1 due to hydrogenation of at least a portion of the one or
more olefins from the hydrocarbon stream 1 while the hydrocarbon
stream 1 is contacted with the hydroprocessing catalyst in the
hydroprocessing reactor 10. In an embodiment, the one or more
olefins are present in the treated hydrocarbon stream 4 in a
concentration of less than 1 wt % based on the total weight of the
treated hydrocarbon stream 4.
[0052] In embodiments, the treated hydrocarbon stream 4 includes
one or more paraffins, and the concentration of the one or more
olefins is less than 1 wt % based on the total weight of the
treated hydrocarbon stream 4.
[0053] In embodiments where the treated hydrocarbon stream 4
includes one or more chloride compounds in a concentration of less
than 3 ppm, the treated hydrocarbon stream 4 may be fed directly to
the steam cracker 30. In alternative embodiments where the treated
hydrocarbon stream 4 includes one or more chloride compounds in a
concentration of 3 ppm or more (e.g., 3 ppm to 5 ppm), the treated
hydrocarbon stream 4 may be blended with a non-chlorinated
hydrocarbon stream 5 to yield a blended hydrocarbon stream 4'
(streams 4' and 5 having dashed lines to denote the alternative
embodiment) having a concentration of one or more chlorides which
is less than 3 ppm based on a total weight of the blended
hydrocarbon stream 4'. The blended hydrocarbon stream 4' may be fed
to the steam cracker 30.
[0054] Steam cracker 30 generally has feed specification
requirements. First, the steam cracker 30 requires the
concentration of chloride compounds in the feed to the steam
cracker 30 to be less than 3 ppm. Second, the steam cracker 30
requires the concentration of olefins in a stream fed to the steam
cracker 30 to be less than 1 wt %. The steam cracker 30 cracks
molecules or cleaves at elevated temperatures carbon-carbon bonds
of the components in the treated hydrocarbon stream 4 or blended
hydrocarbon stream 4' in the presence of steam to yield high value
products such as ethylene, propylene, butene, butadiene, aromatic
compounds, or combinations thereof. The high value products may
flow from the steam cracker 30 via stream 6.
[0055] As is demonstrated in the examples below, it has been found
that dechlorination according to the embodiments disclosed herein
can occur over the operating temperature ranges disclosed herein
for the hydroprocessing reactor 10, including operating
temperatures in the low-end of the temperature ranges disclosed
herein. Removal of chloride compounds to less than 1 ppm occurs at
temperatures below 350.degree. C. Moreover, achieving sub-ppm
chloride compound concentrations is possible with initial chloride
content in the hydrocarbon stream 1 of 1,000 ppm or more. Moreover
still, removal of chloride compounds is effective for different
types and classes of chlorides present in the hydrocarbon stream 1.
When the hydroprocessing reaction is conducted at temperatures at
or above 350.degree. C., it has been found that the treated
hydrocarbon product contains 3 ppm or higher chloride content. In
such cases, the treated hydrocarbon product stream can be blended
as described herein with a non-chlorinated stream 5 in such
proportions to make the combined blended hydrocarbon stream 4' meet
the steam cracker feed specifications.
[0056] Operation at low temperatures (e.g., less than 350.degree.
C.) also has an added advantage of corrosion mitigation of the
reactor metallurgy. For most metals and alloys used in the
commercial reactors, corrosion rates start to increase at reactor
temperatures over 300.degree. C. It has been found that the
efficiency of dechlorination according to the disclosed embodiments
is good at reactor temperatures below 350.degree. C., and the
dechlorination process works with a sulphided Co--Mo catalyst on an
alumina support even as low as 260.degree. C., with the chlorides
in the treated product being less than 1 ppm. Thus, the metallurgy
corrosion issue is mitigated and longer equipment life is possible
while achieving dechlorination to levels desirable for feed to
steam cracker 30. The processes disclosed herein have been
demonstrated to work at pressures as low as 20 barg, which is a
less severe condition than the conditions typically employed with a
commercial hydrotreating catalyst. Ability to operate at lower
pressures reduces the required pressure rating for process vessels
(e.g., the hydroprocessing reactor 10) and provides an opportunity
for reduced investment costs.
[0057] The disclosed embodiments also demonstrate olefins in the
hydrocarbon product are reduced typically to less than 1 wt % of
the treated hydrocarbon stream 4 from a feed olefin concentration
of 20 wt % or more in the hydrocarbon stream 1. Thus, the disclosed
processes achieve the requirements of chloride content and olefin
content of the feed for a steam cracker 30.
EXAMPLES
[0058] The subject matter having been generally described, the
following examples are given as particular embodiments of the
disclosure and to demonstrate the practice and advantages thereof.
It is understood that the examples are given by way of illustration
and are not intended to limit the specification of the claims to
follow in any manner.
[0059] Examples 1 to 5 were conducted in a fixed bed reactor
located inside a 3-zone split-tube furnace. The reactor internal
diameter was 13.8 mm and had concentrically located bed thermowell
of 3 mm outer diameter. The reactor was 48.6 cm long. Commercial
hydroprocessing catalyst of Co--Mo on alumina (8 g bone dry weight)
was broken along the length to particles of 1.5 mm long and diluted
with SiC in the ratio of 60% SiC to 40% catalyst to give a mean
particle diameter of 0.34 mm. This was done to avoid slip through
of the chlorides due to wall slip or channeling in the small
diameter reactor. Pre-heating bed and post-catalyst inert beds was
provided in the form of 1 mm glass beads. The catalyst bed
temperature was controlled to isothermal by varying the controlled
furnace zone skin temperatures. The hydroprocessing catalyst was
sulphided using 3 wt % S in hexadecane (S was introduced as
dimethyl disulphide). Liquid feed (i.e., the hydrocarbon stream)
was fed through a metering pump and H.sub.2 gas was fed using a
mass flow controller. The reactor effluent gases (i.e., hydrocarbon
product) were cooled to condense out the liquids (i.e., the treated
hydrocarbon stream in the form of a liquid product) under pressure
while allowing non-condensed gases (e.g., containing chloride(s),
chlorine, hydrogen sulphide, or combinations thereof) to separate.
Following liquid condensation, the pressure of the liquids was
reduced and effluent gas flow was scrubbed in a caustic scrubber
and measured using a drum-type wet gas meter. The effluent gas flow
was analyzed using a refinery gas analyzer (a custom gas analyzer
from M/s AC Analyticals BV). The liquid product olefin content was
determined using a Detailed Hydrocarbon Analyzer GC (DHA), and a
boiling point characterization was obtained using a SIMDIS GC. The
liquid product chloride content was measured using a Chlora
M-series analyzer (monochromatic wavelength dispersive X-ray
Fluorescence technique, ASTM D7536).
Example 1
[0060] In Example 1, a feed was prepared by mixing plastic
pyrolysis oil (36.3 g) with n-hexadecane (240 g), and then adding
dimethyl disulphide (the sulphide) and 1-chlorohexane (the chloride
compound) to give a sulphur content of 2.34 wt % and 836 ppm
chloride in the feed. This feed was used as a hydrocarbon stream
which was contacted with the sulphided hydroprocessing catalyst in
the packed bed reactor as mentioned above in the presence of
H.sub.2 under several operating conditions as provided in the table
below:
TABLE-US-00001 Cl, ppm in T, .degree. C. P, barg WHSV, hr.sup.-1
H.sub.2/HC, NL/L liquid product 300 60 0.92 414 0.32 300 40 0.92
414 0.87 350 40 0.92 414 3.42 400 40 0.92 414 3.15
[0061] Example 1 demonstrates it is possible to dechlorinate a
hydrocarbon stream containing plastic pyrolysis oil and having
chloride compounds from a chloride content of more than 800 ppm
chlorides to less than 5 ppm in the liquid product. As can be seen
from the above table, the chloride content of the liquid product
(i.e., the treated hydrocarbon stream) increases when the reactor
bed temperature is increased to at or above 350.degree. C. At
temperatures below 350.degree. C., Example 1 demonstrates removal
of chloride compounds to chloride contents less than 3 ppm, and
even sub-ppm levels.
Example 2
[0062] In Example 2, a feed was prepared by adding dimethyl
disulphide (the sulphide) and 2-chloropentane, 3-chloro-3-methyl
pentane, 1-chlorohexane, (2-chloroethyl) benzene, and chlorobenzene
(the chloride compounds) to n-hexadecane to give a sulphur content
of 2 wt % in the mixture and a chloride content of 1,095 ppm in the
mixture. Each of the chloride compounds contributed approximately
220 ppm to the feed mixture. This feed was used as a hydrocarbon
stream which was contacted with the hydroprocessing catalyst in the
packed bed reactor as mentioned above in the presence of H.sub.2 at
300.degree. C. reactor bed temperature, 40 barg reactor pressure,
414 NL/L H.sub.2/HC flow ratio, and 0.92 hr.sup.-1 weight hourly
space velocity (WHSV). The chloride content of the liquid product
(i.e., treated hydrocarbon stream) was 0.23 ppm.
[0063] Example 2 demonstrates it is possible to dechlorinate a
hydrocarbon stream containing no olefins and chloride compounds
from a chloride content of about 1,100 ppm chlorides to the sub-ppm
level in the in the liquid product.
Example 3
[0064] In Example 3, a hydrocarbon feed mixture was prepared to
contain 30 wt % n-hexadecane, 10 wt % i-octane, 20 wt % 1-decene,
20 wt % cyclohexane, and 20 wt % ethyl benzene. To this the organic
chlorides mentioned in Example 2 above were added along with
dimethyl disulphide to give 205 ppm organic chlorides and 2 wt % S
in the mixture. This feed was used as a hydrocarbon stream which
was contacted with the hydroprocessing catalyst in the packed bed
reactor as mentioned above in the presence of H.sub.2 at conditions
of 300.degree. C. reactor temperature, 60 barg reactor pressure,
0.92 hr.sup.-1 WHSV and 414 NL/L H.sub.2/HC flow ratio. The liquid
product (analyzed in DHA) contained 0.183 wt % olefins and 0.11
ppmw chlorides.
[0065] Example 3 demonstrates removal of olefins from a hydrocarbon
stream such that the liquid product has less than 1 wt % olefin
content needed in a steam cracker feed.
Example 4
[0066] In Example 4, a hydrocarbon feed mixture was prepared to
contain 30 wt % n-hexadecane, 10 wt % i-octane, 20 wt % 1-decene,
20 wt % cyclohexane, and 20 wt % ethyl benzene. To this the organic
chlorides mentioned in Example 2 above were added along with
dimethyl disulphide to give 205 ppm organic chlorides and 2 wt % S
in the mixture. This feed was used as a hydrocarbon stream which
was contacted with the hydroprocessing catalyst in the packed bed
reactor as mentioned above in the presence of H.sub.2 at conditions
of 260.degree. C. reactor temperature, 60 barg reactor pressure,
0.92 hr.sup.-1 WHSV and 414 NL/L H.sub.2/HC flow ratio. The liquid
product (i.e., the treated hydrocarbon stream) contained 0.1 ppm
chloride.
[0067] Example 4 demonstrates the effective removal of chloride
compounds from a hydrocarbon stream at very low temperatures.
Example 5
[0068] In Example 5, a hydrocarbon feed mixture was prepared to
contain 30 wt % n-hexadecane, 10 wt % i-octane, 20 wt % 1-decene,
20 wt % cyclohexane, and 20 wt % ethyl benzene. To this the organic
chlorides mentioned in Example 2 above were added along with
dimethyl disulphide to give 205 ppm organic chlorides and 2 wt % S
in the mixture. This feed was used as a hydrocarbon stream which
was contacted with the hydroprocessing catalyst in the packed bed
reactor as mentioned above in the presence of H.sub.2 at conditions
of 300.degree. C. reactor temperature, 20 barg reactor pressure,
0.92 hr.sup.-1 WHSV and 414 NL/L H.sub.2/HC flow ratio. The liquid
product (i.e., the treated hydrocarbon stream) contained 0.09 ppmw
chloride and 0.05 wt % olefins.
[0069] Example 5 demonstrates the effective removal of chloride
compounds from a hydrocarbon stream at low operating pressures.
Example 6
[0070] Example 6 demonstrates a process for sulphiding a
hydroprocessing catalyst. The particular steps of the process are
shown in FIG. 2. The time of 0 hours (zero time) in FIG. 2
corresponds to a time after the hydroprocessing catalyst is
introduced into the hydroprocessing reactor.
[0071] At ambient temperature, the hydroprocessing reactor (having
previously been loaded with the hydroprocessing catalyst) was
purged with hydrogen for 30 to 60 minutes at a set operating
pressure (e.g., 40 to 60 barg). The set operating pressure was
maintained by venting the reactor when the pressure of the reactor
during hydrogen purging increased above the set operating pressure
(e.g., due to a hydrogen source pressure greater than the set
operating pressure).
[0072] After purging the hydroprocessing reactor for 30-60 minutes
at ambient temperature, the hydrogen purge was stopped.
[0073] Still at the ambient temperature, the sulphiding feed was
then introduced into the reactor using a high pressure pump against
the set reactor pressure at a weight hourly space velocity (WHSV)
of 3 hr.sup.-1 (on bone-dry catalyst basis). The sulphiding feed
(e.g., for use in doping stream 7 of FIG. 1) was prepared by mixing
n-hexadecane with dimethyl disulphide in appropriate quantity to
give 3 wt % sulphur based on total weight of the sulphiding feed.
For the sulphiding feed, as per catalyst sulphiding protocol
followed, cracked feedstock cannot be used. Hence, n-hexadecane is
used. In place of n-hexadecane, straight-run naphtha, diesel, or
vacuum gas oils can also be used.
[0074] FIG. 2 indicates the hydroprocessing catalyst was soaked
with a sulphiding feed without a flow of hydrogen in the reactor
and at ambient temperature for a period of 3 hours (ending at time
3.5 hours after zero time in FIG. 2). Catalyst soaking provides for
complete wetting of the hydroprocessing catalyst; however, soaking
is optional. Liquid was drained from the bottom of a downstream gas
liquid separator.
[0075] After introducing the sulphiding feed to the reactor, the
hydroprocessing reactor bed temperature was raised to 250.degree.
C. at a rate of 30.degree. C. per hour with a flow of H.sub.2 at a
ratio of 200 NL H.sub.2/L liquid feed. As shown in FIG. 2, the
temperature was increased from a time of 3.5 hours to a time of
10.8 hours after zero time.
[0076] The hydroprocessing reactor bed temperature was then held at
250.degree. C. for a period of 8 hours. As shown in FIG. 2, the
temperature was held from a time of 10.8 hours to a time of 18.8
hours after zero time.
[0077] After holding the bed temperature, the bed temperature was
further increased to 320.degree. C. to 350.degree. C. at a rate of
20.degree. C. per hour without any temperature overshoot at the
final temperature. As shown in FIG. 2, the temperature was
increased from a time of 18.8 hours to a time of 22.3 hours after
zero time.
[0078] The hydroprocessing reactor bed temperature was then
maintained at 320.degree. C. to 350.degree. C. for a period of 8
hours. As shown in FIG. 2, the temperature was maintained at
320.degree. C. to 350.degree. C. from a time of 22.3 hours to a
time of 30.0 hours after zero time.
[0079] During the step of maintaining the temperature at
320.degree. C. to 350.degree. C. for 8 hours, after 5 hours of
maintaining the temperature at 320.degree. C. to 350.degree. C.,
gas sampling began, and a first gas sample was obtained from the
reactor effluent. A second gas sample was obtained close to 8 hours
while the bed temperature is maintained at 320.degree. C. to
350.degree. C. The first and second gas samples were analyzed in a
refinery gas analyzer (RGA) gas chromatograph and constancy of
H.sub.2S concentration in reactor effluent gases in the first and
second samples signified further uptake of sulphur on the catalyst
did not take place. This marked the completion of the catalyst
sulphiding process. If the first and second samples had not
exhibited constancy in H.sub.2S concentration, additional samples
would have been taken and the temperature maintained until two
successive samples exhibited constancy in H.sub.2S
concentration.
[0080] The present disclosure is further illustrated by the
following embodiments, which are not to be construed in any way as
imposing limitations upon the scope thereof. On the contrary, it is
to be clearly understood that resort can be had to various other
aspects, embodiments, modifications, and equivalents thereof which,
after reading the description herein, can be suggest to one of
ordinary skill in the art without departing from the spirit of the
present invention or the scope of the appended claims.
ADDITIONAL DISCLOSURE
[0081] The following are enumerated embodiments which are provided
as non-limiting examples:
[0082] A first embodiment, which is a process for dechlorination of
a hydrocarbon stream comprising:
[0083] contacting the hydrocarbon stream with a hydroprocessing
catalyst in the presence of hydrogen to yield a hydrocarbon
product, wherein the hydrocarbon stream comprises one or more
chloride compounds in a concentration of 5 ppm or more based on a
total weight of the hydrocarbon stream; and
[0084] recovering a treated hydrocarbon stream from the hydrocarbon
product, wherein the treated hydrocarbon stream comprises the one
or more chloride compounds in a concentration of less than 5 ppm
based on a total weight of the treated hydrocarbon stream.
[0085] A second embodiment, which is the process of the first
embodiment, wherein the treated hydrocarbon stream comprises the
one or more chloride compounds in a concentration of less than 1
ppm based on the total weight of the treated hydrocarbon
stream.
[0086] A third embodiment, which is the process of any one of the
first through the second embodiments, wherein the hydrocarbon
stream comprises the one or more chloride compounds in a
concentration of greater than 200 ppm based on a total weight of
the hydrocarbon stream.
[0087] A fourth embodiment, which is the process of any one of the
first through the third embodiments, wherein the hydrocarbon stream
further comprises one or more olefins, wherein the treated
hydrocarbon stream further comprises the one or more olefins in a
concentration of less than 1 wt % based on the total weight of the
treated hydrocarbon stream.
[0088] A fifth embodiment, which is the process of the fourth
embodiment, wherein the one or more olefins are present in the
hydrocarbon stream in a concentration of 20 wt % or more based on
the total weight of the hydrocarbon stream.
[0089] A sixth embodiment, which is the process of any one of the
fourth through the fifth embodiments, wherein the concentration of
the one or more olefins in the treated hydrocarbon stream is less
than the concentration of the one or more olefins in the
hydrocarbon stream due to hydrogenation of at least a portion of
the one or more olefins from the hydrocarbon stream during the step
of contacting.
[0090] A seventh embodiment, which is the process of any one of the
first through the sixth embodiments, wherein the hydrocarbon stream
is one or more of a plastic pyrolysis oil and a tire pyrolysis
oil.
[0091] An eighth embodiment, which is the process of any one of the
first through the seventh embodiments, wherein the hydrocarbon
stream further comprises paraffins.
[0092] A ninth embodiment, which is the process of the eighth
embodiment, wherein the hydrocarbon stream further comprises one or
more olefins, wherein the treated hydrocarbon stream further
comprises the paraffins and the one or more olefins, wherein the
one or more olefins of the treated hydrocarbon stream are present
in a concentration of less than 1 wt % based on the total weight of
the treated hydrocarbon stream.
[0093] A tenth embodiment, which is the process of any one of the
first through third and eighth embodiments, wherein the hydrocarbon
stream comprises no olefins.
[0094] An eleventh embodiment, which is the process of any one of
the first through the tenth embodiments, further comprising:
[0095] adding one or more sulphides to the hydrocarbon stream
before the step of contacting.
[0096] A twelfth embodiment, which is the process of the eleventh
embodiment, wherein the one or more sulphides are added to the
hydrocarbon stream in an amount such that a sulphur content in the
hydrocarbon stream is about 0.5 wt % to about 5 wt % based on the
total weight of the hydrocarbon stream.
[0097] A thirteenth embodiment, which is the process of any one of
the first through the twelfth embodiments, wherein the hydrocarbon
stream further comprises one or more sulphides.
[0098] A fourteenth embodiment, which is the process of the
thirteen embodiment, wherein the one or more sulphides of the
hydrocarbon stream are present in an amount such that a sulphur
content of the hydrocarbon stream is about 0.5 wt % to about 5 wt %
based on the total weight of the hydrocarbon stream.
[0099] A fifteenth embodiment, which is the process of any one of
the first through the fourteenth embodiments, wherein the
hydroprocessing catalyst comprises cobalt and molybdenum on an
alumina support, nickel and molybdenum on an alumina support, or
nickel and molybdenum sulphides.
[0100] A sixteenth embodiment, which is the process of any one of
the first through the fifteenth embodiments, wherein contacting the
hydrocarbon stream with the hydroprocessing catalyst comprises:
[0101] contacting one or more sulphides contained in or added to
the hydrocarbon stream with the hydroprocessing catalyst.
[0102] A seventeenth embodiment, which is the process of the
sixteenth embodiment, wherein the one or more sulphides are
contained in or added to the hydrocarbon stream in an amount such
that a sulphur content of the hydrocarbon stream is about 2 wt %
based on the total weight of the hydrocarbon stream.
[0103] An eighteenth embodiment, which is the process of any one of
the first through the seventeenth embodiments, wherein the step of
contacting is performed at a temperature of 100.degree. C. to
450.degree. C.
[0104] A nineteenth embodiment, which is the process of any one of
the first through the eighteenth embodiments, wherein the step of
contacting is performed at a temperature of 100.degree. C. to
350.degree. C.
[0105] A twentieth embodiment, which is the process of any one of
the first through the nineteenth embodiments, wherein the step of
contacting is performed at a temperature of 260.degree. C. to
350.degree. C.
[0106] A twenty-first embodiment, which is the process of any one
of the first through the twentieth embodiments, wherein the
hydrocarbon stream is in a liquid phase.
[0107] A twenty-second embodiment, which is the process of any one
of the first through the twenty-first embodiments, wherein the step
of contacting is performed at a weight hourly space velocity of 0.1
to 10 hr.sup.-1.
[0108] A twenty-third embodiment, which is the process of any one
of the first through the twenty-second embodiments, wherein the
step of contacting is performed at a hydrogen to hydrocarbon ratio
of 10 to 3,000 NL/L.
[0109] A twenty-fourth embodiment, which is the process of any one
of the first through the twenty-third embodiments, wherein the step
of contacting is performed at a pressure of 1 to 200 barg.
[0110] A twenty-fifth embodiment, which is the process of any one
of the first through the twenty-fourth embodiments, wherein the
treated hydrocarbon stream comprises the one or more chloride
compounds in a concentration of less than 3 ppm based on a total
weight of the treated hydrocarbon, the process further
comprising:
[0111] feeding the treated hydrocarbon stream to a steam
cracker.
[0112] A twenty-sixth embodiment, which is the process of any one
of the first through the twenty-fifth embodiments, further
comprising:
[0113] blending the treated hydrocarbon stream with a
non-chlorinated hydrocarbon stream to yield a blended hydrocarbon
stream comprising the one or more chloride compounds in a
concentration of less than 3 ppm based on a total weight of the
blended hydrocarbon stream; and
[0114] feeding the blended hydrocarbon stream to a steam
cracker.
[0115] A twenty-seventh embodiment, which is the process of any one
of the first through the twenty-sixth embodiments, wherein
recovering a treated hydrocarbon stream from the hydrocarbon
product comprises:
[0116] separating a treated product from a chlorine-containing gas
in a separator; and
[0117] flowing the treated product in the treated hydrocarbon
stream from the separator.
[0118] A twenty-eighth embodiment, which is the process of any one
of the first through the twenty-seventh embodiments, wherein no
hydrogen halides and no halogenated organic compounds are recycled
to the hydroprocessing reactor.
[0119] A twenty-ninth embodiment, which is the process of any one
of the first through the twenty-eighth embodiments, wherein the
step of contacting is performed without use of chlorine
sorbents.
[0120] A thirtieth embodiment, which is the process of any one of
the first through the twenty-ninth embodiments, wherein the step of
contacting is performed without the presence of Na.sub.2CO.sub.3 in
an effective amount to function as a dechlorinating agent.
[0121] A thirty-first embodiment, which is the process of any one
of the first through the thirtieth embodiments, wherein the
hydroprocessing reactor is configured to operate in the slurry
phase.
[0122] A thirty-second embodiment, which is the process of any one
of the first through the thirty-first embodiments, wherein the step
of contacting includes simultaneous dechlorination and
hydrogenation of the hydrocarbon stream such that the treated
hydrocarbon stream comprises the one or more chloride compounds in
a concentration less than 1 ppm and one or more olefins in a
concentration less than 1 wt % based on the total weight of the
treated hydrocarbon stream.
[0123] A thirty-third embodiment, which is the process of any one
of the first through the thirty-second embodiments, wherein the
hydroprocessing catalyst is sulphided.
[0124] A thirty-fourth embodiment, which is the process of any one
of the first through the thirty-third embodiments, wherein the one
or more chloride compounds include chlorine-containing
hydrocarbons.
[0125] A thirty-fifth embodiment, which is the process of the
thirty-fourth embodiment, wherein the chlorine-containing
hydrocarbons include aliphatic chlorine-containing hydrocarbons,
aromatic chlorine-containing hydrocarbons, other hydrocarbons
containing chlorides, or a combination of any of aliphatic
chlorine-containing hydrocarbons, aromatic chlorine-containing
hydrocarbons, and other hydrocarbons containing chlorides.
[0126] A thirty-sixth embodiment, which is the process of any one
of the thirty-fourth through the thirty-fifth embodiments, wherein
the chlorine-containing hydrocarbons include 1-chlorohexane,
2-chloropentane, 3-chloro-3-methyl pentane, (2-chloroethyl)
benzene, chlorobenzene, or combinations thereof.
[0127] While embodiments of the disclosure have been shown and
described, modifications thereof can be made without departing from
the spirit and teachings of the invention. The embodiments and
examples described herein are exemplary only, and are not intended
to be limiting. Many variations and modifications of the invention
disclosed herein are possible and are within the scope of the
invention.
[0128] Accordingly, the scope of protection is not limited by the
description set out above but is only limited by the claims which
follow, that scope including all equivalents of the subject matter
of the claims. Each and every claim is incorporated into the
specification as an embodiment of the present invention. Thus, the
claims are a further description and are an addition to the
detailed description of the present invention. The disclosures of
all patents, patent applications, and publications cited herein are
hereby incorporated by reference.
* * * * *