U.S. patent number 3,772,184 [Application Number 05/209,304] was granted by the patent office on 1973-11-13 for reforming petroleum hydrocarbons with catalysts promoted with gallium and rhenium.
This patent grant is currently assigned to Standard Oil Company. Invention is credited to Ralph J. Bertolacini, Dae K. Kim.
United States Patent |
3,772,184 |
Bertolacini , et
al. |
November 13, 1973 |
**Please see images for:
( Certificate of Correction ) ** |
REFORMING PETROLEUM HYDROCARBONS WITH CATALYSTS PROMOTED WITH
GALLIUM AND RHENIUM
Abstract
The catalyst comprises a hydrogenation component, a small amount
of rhenium, and a small amount of gallium on a solid catalytic
support comprising a porous refractory inorganic oxide. The rhenium
and the gallium may be present either in the elemental form or as
compounds. The preferred hydrogenation component is a Group VIII
noble metal and the preferred porous refractory inorganic oxide is
a catalytically active alumina. The reforming process comprises
contacting a petroleum hydrocarbon stream in a reforming zone under
reforming conditions and in the presence of hydrogen with the
above-described catalyst. In one embodiment, the process comprises
contacting a partially-reformed hydrocarbon stream in a reforming
zone under reforming conditions and in the presence of hydrogen
with the above catalyst. In another embodiment, the process
comprises contacting a naphtha in a reforming zone under reforming
conditions and in the presence of hydrogen with the above catalyst.
In a third embodiment, the process comprises contacting the
petroleum hydrocarbon stream in a first reforming zone under
reforming conditions and in the presence of hydrogen with a first
reforming catalyst to produce a first reformate and subsequently
contacting the first reformate in a second reforming zone under
reforming conditions and in the presence of hydrogen with a second
reforming catalyst, said second reforming catalyst being the
catalyst described in the preceding paragraph.
Inventors: |
Bertolacini; Ralph J.
(Chesterton, IN), Kim; Dae K. (Evanston, IL) |
Assignee: |
Standard Oil Company (Chicago,
IL)
|
Family
ID: |
22778237 |
Appl.
No.: |
05/209,304 |
Filed: |
December 17, 1971 |
Current U.S.
Class: |
208/65; 208/139;
208/138; 502/228 |
Current CPC
Class: |
C10L
7/02 (20130101); C10G 35/06 (20130101); C10G
35/09 (20130101); B01J 23/6567 (20130101); C10G
59/02 (20130101); C09K 8/64 (20130101) |
Current International
Class: |
C09K
8/64 (20060101); C10L 7/00 (20060101); C10L
7/02 (20060101); C10G 35/09 (20060101); C10G
35/00 (20060101); C10G 35/06 (20060101); B01J
23/54 (20060101); B01J 23/656 (20060101); C10G
59/02 (20060101); C10G 59/00 (20060101); C09K
8/60 (20060101); C10g 035/08 (); C10g 039/00 ();
B01j 011/78 (); B01j 011/08 () |
Field of
Search: |
;208/65,139US
;252/442,466PT |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Gantz; Delbert E.
Assistant Examiner: Berger; S.
Claims
What is claimed is:
1. A catalytic composition comprising about 0.05 wt.% to about 2
wt.% Group VIII noble metal as a hydrogenation component, a small
amount of rhenium, and a small amount of gallium on a solid
catalytic support comprising a porous refractory inorganic oxide,
said small amount rhenium being within the range of about 0.05 wt.%
to about 3 wt.% and said small amount of gallium being within the
range of about 0.05 wt.% to about 3 wt.%, each amount being
calculated as the element and based upon the total weight of said
catalytic composition.
2. The catalytic composition of claim 1 wherein said porous
refractory inorganic oxide is a catalytically active alumina.
3. The catalytic composition of claim 1 wherein said catalytic
composition is further characterized by a halide, said halide being
present in an amount of about 0.1 wt.% to about 2 wt.%, based upon
the total weight of said catalytic composition.
4. A process for reforming a petroleum hydrocarbon stream, which
process comprises contacting said hydrocarbon stream in a reforming
zone under reforming conditions and in the presence of hydrogen
with the catalytic composition of claim 1.
5. A process for reforming a petroleum hydrocarbon stream, which
process comprises contacting said hydrocarbon stream in a first
reforming zone under reforming conditions and in the presence of
hydrogen with a catalyst consisting essentially of a platinum group
metal, 0 wt.% to about 2 wt.% rhenium, and a halide on a
catalytically active alumina to produce a first reformate and
subsequently contacting said first reformate in a second reforming
zone under reforming conditions in the presence of hydrogen with
the catalytic composition of claim 1.
6. A process for reforming a petroleum hydrocarbon stream that has
been partially reformed, which process comprises contacting said
hydrocarbon stream in a reforming zone under reforming conditions
and in the presence of hydrogen with the catalytic composition of
claim 1.
7. The catalytic composition of claim 2 wherein said catalytic
composition is further characterized by a halide, said halide being
present in an amount of about 0.1 wt.% to about 2 wt.%, based upon
the total weight of said catalytic composition.
8. The catalytic composition of claim 3 wherein said halide is
chloride.
9. The process of claim 4 wherein said petroleum hydrocarbon stream
is a member selected from the group consisting of a virgin naphtha,
a cracked naphtha, a hydrocarbon fraction boiling in the gasoline
boiling range, a partially-reformed naphtha, and mixtures
thereof.
10. The process of claim 5 wherein said petroleum hydrocarbon
stream is a member selected from the group consisting of a virgin
naphtha, a cracked naphtha, a hydrocarbon fraction boiling in the
gasoline boiling range, a partially-reformed naphtha, and mixtures
thereof.
11. The catalytic composition of claim 1 wherein said Group VIII
noble metal is platinum.
12. The catalytic composition of claim 2 wherein said Group VIII
noble metal is platinum.
13. The catalytic composition of claim 11 wherein said catalytic
composition is further characterized by a halide, said halide being
present in an amount of about 0.1 wt.% to about 2 wt.%, based upon
the total weight of said catalytic composition.
14. The catalytic composition of claim 12 wherein said catalytic
composition is further characterized by a halide, said halide being
present in an amount of about 0.1 wt.% to about 2 wt.%, based upon
the total weight of said catalytic composition.
15. The catalytic composition of claim 13 wherein said halide is
chloride.
16. The catalytic composition of claim 14 wherein said halide is
chloride.
17. The catalytic composition of claim 7 wherein said halide is
chloride.
18. A process for reforming a petroleum hydrocarbon stream, which
process comprises contacting said hydrocarbon stream in a reforming
zone under reforming conditions and in the presence of hydrogen
with the catalytic composition of claim 15.
19. A process for reforming a petroleum hydrocarbon stream, which
process comprises contacting said hydrocarbon stream in a first
reforming zone under reforming conditions and in the presence of
hydrogen with a catalyst consisting essentially of a platinum group
metal, 0 wt.% to about 2 wt.% rhenium, and a halide on a
catalytically active alumina to produce a first reformate and
subsequently contacting said first reformate in a second reforming
zone under reforming conditions in the presence of hydrogen with
the catalytic composition of claim 15.
20. A process for reforming a petroleum hydrocarbon stream that has
been partially reformed, which process comprises contacting said
hydrocarbon stream in a reforming zone under reforming conditions
and in the presence of hydrogen with the catalytic composition of
claim 15.
21. A process for reforming a petroleum hydrocarbon stream, which
process comprises contacting said hydrocarbon stream in a reforming
zone under reforming conditions and in the presence of hydrogen
with the catalytic composition of claim 16.
22. A process for reforming a petroleum hydrocarbon stream, which
process comprises contacting said hydrocarbon stream in a first
reforming zone under reforming conditions and in the presence of
hydrogen with a catalyst consisting essentially of a platinum group
metal, 0 wt.% to about 2 wt.% rhenium, and a halide on a
catalytically active alumina to produce a first reformate and
subsequently contacting said first reformate in a second reforming
zone under reforming conditions in the presence of hydrogen with
the catalytic composition of claim 16.
23. A process for reforming a petroleum hydrocarbon stream that has
been partially reformed, which process comprises contacting said
hydrocarbon stream in a reforming zone under reforming conditions
and in the presence of hydrogen with the catalytic composition of
claim 16.
24. A process for reforming a petroleum hydrocarbon stream, which
process comprises contacting said hydrocarbon stream in a reforming
zone under reforming conditions and in the presence of hydrogen
with the catalytic composition of claim 17.
25. A process for reforming a petroleum hydrocarbon stream, which
process comprises contacting said hydrocarbon stream in a first
reforming zone under reforming conditions and in the presence of
hydrogen with a catalyst consisting essentially of a platinum group
metal, 0 wt.% to about 2 wt.% rhenium, and a halide on a
catalytically active alumina to produce a first reformate and
subsequently contacting said first reformate in a second reforming
zone under reforming conditions in the presence of hydrogen with
the catalytic composition of claim 17.
26. A process for reforming a petroleum hydrocarbon stream that has
been partially reformed, which process comprises contacting said
hydrocarbon stream in a reforming zone under reforming conditions
and in the presence of hydrogen with the catalytic composition of
claim 17.
27. The process of claim 18 wherein said petroleum hydrocarbon
stream is a member selected from the group consisting of a virgin
naphtha, a cracked naphtha, a hydrocarbon fraction boiling in the
gasoline boiling range, a partially-reformed naphtha, and mixtures
thereof.
28. The process of claim 18 wherein said reforming conditions
comprise an average catalyst temperature of about 700.degree.F. to
about 1,050.degree.F., a pressure of about 50 psig to about 1,000
psig, a WHSV of about 0.5 to about 15 weight units of hydrocarbon
per hour per weight unit of catalyst, and a hydrogen addition rate
of about 1,500 SCFB to about 15,000 SCFB.
29. The process of claim 19 wherein said petroleum hydrocarbon
stream is a member selected from the group consisting of a virgin
naphtha, a cracked naphtha, a hydrocarbon fraction boiling in the
gasoline boiling range, a partially-reformed naphtha, and mixtures
thereof.
30. The process of claim 19 wherein said reforming conditions
comprise an average catalyst temperature of about 700.degree.F. to
about 1,050.degree.F., a pressure of about 50 psig to about 1,000
psig, a WSHV of about 0.5 to about 15 weight units of hydrocarbon
per hour per weight unit of catalyst, and a hydrogen addition rate
of about 1,500 SCFB to about 15,000 SCFB.
31. The process of claim 21 wherein said petroleum hydrocarbon
stream is a member selected from the group consisting of a virgin
naphtha, a cracked naphtha, a hydrocarbon fraction boiling in the
gasoline boiling range, a partially-reformed naphtha, and mixtures
thereof.
32. The process of claim 21 wherein said reforming conditions
comprise an average catalyst temperature of about 700.degree.F. to
about 1,050.degree.F., a pressure of about 50 psig to about 1,000
psig, a WHSV of about 0.5 to about 15 weight units of hydrocarbon
per hour per weight unit of catalyst, and a hydrogen addition rate
of about 1,500 SCFB to about 15,000 SCFB.
33. The process of claim 22 wherein said petroleum hydrocarbon
stream is a member selected from the group consisting of a virgin
naphtha, a cracked naphtha, a hydrocarbon fraction boiling in the
gasoline boiling range, a partially-reformed naphtha, and mixtures
thereof.
34. The process of claim 22 wherein said reforming conditions
comprise an average catalyst temperature of about 700.degree.F. to
about 1,050.degree.F., a pressure of about 50 psig to about 1,000
psig, a WHSV of about 0.5 to about 15 weight units of hydrocarbon
per hour per weight unit of catalyst, and a hydrogen addition rate
of about 1,500 SCFB to about 15,000 SCFB.
35. The process of claim 24 wherein said petroleum hydrocarbon
stream is a member selected from the group consisting of a virgin
naphtha, a cracked naphtha, a hydrocarbon fraction boiling in the
gasoline boiling range, a partially-reformed naphtha, and mixtures
thereof.
36. The process of claim 24 wherein said reforming conditions
comprise an average catalyst temperature of about 700.degree.F. to
about 1,050.degree.F., a pressure of about 50 psig to about 1,000
psig, a WHSV of about 0.5 to about 15 weight units of hydrocarbon
per hour per weight unit of catalyst, and a hydrogen addition rate
of about 1,500 SCFB to about 15,000 SCFB.
37. The process of claim 25 wherein said petroleum hydrocarbon
stream is a member selected from the group consisting of a virgin
naphtha, a cracked naphtha, a hydrocarbon fraction boiling in the
gasoline boiling range, a partially-reformed naphtha, and mixtures
thereof.
38. The process of claim 25 wherein said reforming conditions
comprise an average catalyst temperature of about 700.degree.F. to
about 1,050.degree.F., a pressure of about 50 psig to about 1,000
psig, a WHSV of about 0.5 to about 15 weight units of hydrocarbon
per hour per weight unit of catalyst, and a hydrogen addition rate
of about 1,500 SCFB to about 15,000 SCFB.
39. The process of claim 28 wherein said petroleum hydrocarbon
stream is a member selected from the group consisting of a virgin
naphtha, a cracked naphtha, a hydrocarbon fraction boiling in the
gasoline boiling range, a partially-reformed naphtha, and mixtures
thereof.
40. The process of claim 30 wherein said petroleum hydrocarbon
stream is a member selected from the group consisting of a virgin
naphtha, a cracked naphtha, a hydrocarbon fraction boiling in the
gasoline boiling range, a partially-reformed naphtha, and mixtures
thereof.
41. The process of claim 32 wherein said petroleum hydrocarbon
stream is a member selected from the group consisting of a virgin
naphtha, a cracked naphtha, a hydrocarbon fraction boiling in the
gasoline boiling range, a partially-reformed naphtha, and mixtures
thereof.
42. The process of claim 34 wherein said petroleum hydrocarbon
stream is a member selected from the group consisting of a virgin
naphtha, a cracked naphtha, a hydrocarbon fraction boiling in the
gasoline boiling range, a partially-reformed naphtha, and mixtures
thereof.
43. The process of claim 36 wherein said petroleum hydrocarbon
stream is a member selected from the group consisting of a virgin
naphtha, a cracked naphtha, a hydrocarbon fraction boiling in the
gasoline boiling range, a partially-reformed naphtha, and mixtures
thereof.
44. The process of claim 38 wherein said petroleum hydrocarbon
stream is a member selected from the group consisting of a virgin
naphtha, a cracked naphtha, a hydrocarbon fraction boiling in the
gasoline boiling range, a partially-reformed naphtha, and mixtures
thereof.
Description
BACKGROUND OF THE INVENTION
The reforming of petroleum hydrocarbon streams is one of the
important petroleum refining processes that may be employed to
provide high-octane-number hydrocarbon blending components for
gasoline. In the typical reforming process, the reactions comprise
dehydrogenation reactions, isomerization reactions, and
hydrocracking reactions. The dehydrogenation reactions include the
dehydrogenation of cyclohexanes to aromatics, the
dehydroisomerization of alkylcyclopentanes to aromatics, the
dehydrogenation of paraffins to olefins, and the dehydrocyclization
of paraffins and olefins to aromatics. The isomerization reactions
include isomerization of n-paraffins to isoparaffins, the
hydroisomerization of olefins to isoparaffins, the isomerization of
alkylcyclopentanes to cyclohexanes, and the isomerization of
substituted aromatics. The hydrocracking reactions include
hydrocracking of paraffins and hydrodesulfurization. Adequate
discussion of the reactions occurring in a reforming reaction zone
are presented in CATALYSIS, Vol. VI, P. H. Emmett, editor, Reinhold
Publishing Corporation, 1958, pages 497-498, and PETROLEUM
PROCESSING, R. J. Hengstebeck, McGraw-Hill Book Cmpany, Inc., 1959,
pages 179-184.
It is well known by those skilled in the art that several catalysts
are capable of reforming petroleum naphthas and hydrocarbons that
boil in the gasoline boiling rnage. Although reforming may be
carried out through the use of molybdena-on-alumina catalysts,
chromium-oxides-on-alumina catalysts, platinum-halogen-on-alumina
catalysts, and platinum-aluminosilicate-material-alumina catalysts,
the catalysts employing platinum as a hydrogenation component are
generally employed today in the reforming processes of the
petroleum industry.
Moreover, it is now known that a reforming catalyst may be promoted
by a small amount of gallium and there are disclosed in our
co-pending aplication, U.S. Ser. No. 209,303 filed on Dec. 17,
1971, several embodiments of a process for reforming petroleum
hydrocarbon streams wherein such a catayst is employed.
It has now been found that a catalyst comprising a hydrogenation
component, a small amount of rhenium, and a small amount of gallium
on a solid catalytic support comprising a porous refractory
inorganic oxide may be suitably employed to reform petroleum
hydrocarbon streams.
Embodiments of a reforming process employing this catalytic
composition, i.e., the process of the present invention, provide
high-octance-number blending material for unleaded and/or low-lead
motor fuels.
SUMMARY OF THE INVENTION
Broadly, according to the present invention, there is provided a
catalytic composition for reforming a petroleum hydrocarbon stream,
which catalytic composition comprises a hydrogenation component, a
small amount of rhenium, and a small amount of gallium on a solid
catalytic support comprising a porous refractory inorganic oxide.
The catalytic composition may contain a halide, preferably,
chloride.
The preferred hydrogenation component is a Group VIII noble metal.
The preferred porous refractory inorganic oxide is a catalytically
active alumina.
In one embodiment of the process of the present invention, there is
provided a process for reforming a petroleum hydrocarbon stream.
This embodiment comprises contacting the petroleum hydrocarbon
stream in a reforming zone under reforming conditions and in the
presence of hydrogen with the catalytic composition of the present
invention. The petroleum hydrocarbon stream may be naphtha, or it
may be a partially-reformed hydrocarbon stream.
In another embodiment of the process of the present invention,
there is provided a process for reforming a petroleum hydrocarbon
stream, which process comprises contacting said hydrocarbon stream
in a first reforming zone under reforming conditions and in the
presence of hydrogen with a first reforming catalyst to produce a
first reformate and subsequently contacting said first reformate in
a second reforming zone under reforming conditions and in the
presence of hydrogen with the catalytic composition of the present
invention.
Accordingly, the process may employ the catalytic composition of
the present invention either as the sole catalyst in the reforming
process or as the final catalyst in a multiple-catalyst reforming
system. Preferably, the process employs the catalyst of the
invention in the last reactor, or tail reactor, of a
multiple-reactor reforming system. The selection of the particular
embodiment of the process of the present invention will be dictated
by the feedstock to be reformed. If the hydrocarbon stream has
already been partially reformed, the embodiment of the process
employing the catalytic composition of the present invention as the
sole catalyst is suitable.
BRIEF DESCRIPTION OF THE DRAWINGS
Two figures accompany this document.
FIG. 1 presents a simplified schematic flow diagram of a preferred
embodiment of the process of the present invention, wherein the
catalytic composition of the present invention is employed in the
last reactor, or tail reactor, of a multiple-reactor reforming
system.
FIG. 2 provides a comparison of several catalysts, when each is
employed in a test simultaing a tail-reactor operation.
DESCRIPTION AND PREFERRED EMBODIMENTS
The highly mechanized society of today requires an increasing
demand for very-high-octane-number motor fuels. The process of this
invention is especially advantageous for the production of
high-octane-number blending components for motor fuels by means of
the reforming of petroleum naphthas and petroleum hydrocarbon
streams boiling in the gasoline boiling range. It may be employed
suitably to produce high-octane-number blending components for
unleaded and/or low-lead motor fuels.
The embodiments of the process of the present invention may be used
to reform a feedstock which is a member selected from the group
consisting of a virgin naphtha, a cracked naphtha, a hydrocarbon
fraction boiling in the gasoline boiling range, and mixtures
thereof. It may also be used to reform partially-reformed naphthas
and other hydrocarbon streams. A naphtha will exhibit a boiling
range of about 70.degree.F. to about 500.degree.F., preferably,
about 180.degree.F. to about 400.degree.F. The gasoline boiling
range comprises temperatures of about 120.degree.F. to about
420.degree.F., preferably, about 140.degree.F. to about
380.degree.F. The partially-reformed hydrocarbon streams will
exhibit an unleaded research octane number within the range of
about 75 to about 95. As used herein, the terms "mildly-reformed"
and "partially-reformed" refer to such streams as have been
reformed to an unleaded research octane number of about 75 to about
95.
Since many of the above feedstocks may contain appreciable amounts
of nitrogen and sulfur compounds, which are deleterious to the
first catalyst of that embodiment of the present invention which
employs a multiple-catalyst reforming system, it is preferred that
the feedstock in this case be subjected to a suitable
hydrodesulfurization and/or hydrodenitrogenation treatment, such as
hydrofining, prior to use in the embodiment of the process of the
present invention in order to reduce both the nitrogen and sulfur
levels to tolerable limits.
According to the process of the present invention, there is
provided a process for reforming a petroleum hydrocarbon stream.
One embodiment of this process comprises contacting said
hydrocarbon stream in a first reforming zone under reforming
conditions and in the presence of hydrogen with a first reforming
catalyst to produce a first reformate and subsequently contacting
said first reformate in a second reforming zone under reforming
conditions and in the presence of hydrogen with a second reforming
catalyst comprising a hydrogenation component, a small amount of
rhenium, and a small amount of gallium on a solid catalytic support
comprising a porous refractory inorganic oxide. In another
embodiment, the process comprises contacting a partially-reformed
hydrocarbon stream in a reforming zone under reforming conditions
and in the presence of hydrogen with a catalytic composition
comprising a hydrogenation component, a small amount of rhenium,
and a small amount of gallium on a solid catalytic support
comprising a refractory inorganic oxide.
The first reforming catalyst, i.e., the catalyst that is employed
in the first reforming zone of the
multiple-reforming-zone-embodiment of the process of the present
invention, may be typically a reforming catalyst comprising a
platinum group metal and a halide supported on a catalytically
active alumina. It is contemplated that such catalyst may be
promoted with a small amount of rhenium. It is to be understood
that any suitable reforming catalyst in the art may be employed as
the first catalyst in the first reforming zone, for example, a
molybdena-on-alumina catalyst. A particular first catalyst is a
catalyst consisting essentially of a platinum group metal, rhenium,
and a halide on a catalytically active alumina. A preferred first
catalyst is a catalyst which comprises about 0.1 wt.% to about 2
wt.% platinum, about 0.05 wt.% to about 2 wt.% chloride, and about
0.05 wt.% to about 2 wt.% rhenium on a catalytically active alumina
and which does not contain gallium. The catalytically active
alumina that is employed as the support material for the first
catalyst may be any catalytically active alumina, such as
gamma-alumina or eta-alumina. Such alumina should have an average
pore diameter of about 70 A to about 200 A, or larger. The alumina
should have a surface area of at least 150 square meters per gram.
Suitably, the surface area should be within the range of about 200
to about 800 square meters per gram, or larger.
The second reforming catalyst, i.e., the catalyst that is employed
in the second reforming zone of this multi-zoned embodiment of the
process of the present invention, is the catalytic composition of
the present invention. It comprises a hydrogenation component, a
small amount of rhenium, and a small amount of gallium on a solid
catalytic support comprising a porous refractory inorganic
oxide.
Suitable hydrogenation components that are employed in a typical
reforming catalyst, and that may be employed in the catalyst of the
present invention, include Group VI metals of the Periodic Table of
Elements, particularly, molybdenum and chromium, the oxides of
Group VI metals, and Group VIII metals, particularly, the Group
VIII noble metals. The Group VIII noble metals include ruthenium,
rhodium, palladium, osmium, iridium, and platinum. The preferred
Group VIII noble metal is platinum.
When the hydrogenation component for the catalyst of the present
invention is a Group VIII noble metal, the hydrogenation component
may be present in an amount of about 0.05 wt.%, calculated as the
element and based upon the total weight of the catalyst.
Preferably, the Group VIII noble metal is present in an amount of
about 0.1 wt.% to about 1 wt.%, calculated as the element and based
upon the total weight of the catalyst.
Another essential component of the catalyst of the present
invention is gallium, a member of Group III of the Periodic Table
of Elements. Gallium may be present in an amount of about 0.05 wt.%
to about 3 wt.%, calculated as the element and based upon the total
weight of the catalytic composition. Preferably, gallium is present
in an amount of about 0.1 wt.% to about 1 wt.%.
Rhenium is also an essential component of the catalyst of the
present invention. It may be present in an amount of about 0.05
wt.% to about 3 wt.%, calculated as the element and based upon the
total weight of said catalytic composition.
The solid catalytic support of the catalyst of the present
invention comprises a porous refractory inorganic oxide. The
preferred refractory inorganic oxide is a catalytically active
alumina, such as gamma-alumina, eta-alumina, or mixtures thereof.
The properties of such alumina are presented hereinabove. The solid
catalytic support may also contain a crystalline aluminosilicate
material. Such aluminosilicate material is a large-pore
aluminosilicate material and preferably possesses pores within the
range of about 5 A to about 20 A. A preferred aluminosilicate
material is mordenite or faujasite. Suitably, the aluminosilicate
material is suspended in and distributed throughout a matrix of the
porous refractory inorganic oxide. The aluminosilicate material may
be present in an amount of about 0.5 wt.% to about 25 wt.%, based
upon the weight of the catalytic support. Preferably, the
large-pore crystalline aluminosilicate material has been
cation-exchanged with a member selected from the group consisting
of an alkaline earth metal, a rare earth metal, hydrogen, and a
hydrogen precursor, such as ammonium, to reduce the alkali-metal
content of the aluminosilicate material to a level that is less
than 1 wt.%, calculated as the metal.
The catalyst of the present invention may also contain a halide.
Suitable halides are chlorides and fluorides. The preferred halide
is a chloride. The halide may be present in an amount of about 0.1
wt.% to about 2 wt.%, based upon the total weight of the catalyst.
Preferably, the halide is present in an amount of about 0.1 wt.% to
about 1 wt.%, based upon the weight of the catalyst.
The catalyst of the present invention may be prepared in various
ways. For example, a soluble compound of the hydrogenation metal
and soluble compounds of rhenium and gallium may be added to a sol
or gel of the refractory inorganic oxide. This composition may be
thoroughly blended and the sol or gel mixture may be subsequently
co-gelled by the addition of dilute ammonia. The resulting
co-gelled material may then be dried and calcined. If an
aluminosilicate material is to be a component of the catalytic
composition, it may be added in a finely divided form to the sol or
gel of the refractory inorganic oxide and suitable compounds of the
hydrogenation component, rhenium, and gallium may be added thereto,
and the resulting composition may then be thoroughly blended prior
to co-gelling, drying, and calcining. In another method of
preparation, the refractory inorganic oxide is gelled, dried,
pelleted, calcined, and cooled, and the resulting composition is
then impregnated with one or more solutions of the hydrogenation
component, rhenium, and gallium. Suitable calcination conditions
comprise a temperature in the range of about 900.degree.F. to about
1,100.degree.F. and a calcination time of about 1 to about 20
hours. Suitable drying conditions comprise a temperature in the
range of about 200.degree.F. to about 400.degree.F. and a drying
time of about 3 to about 30 hours. Preferably, drying conditions
comprise a temperature of about 250.degree.F. for about 8 to about
16 hours and calcination conditions comprise a temperature of about
1,000.degree.F. for about 2 to about 6 hours. The halide may be
incorporated into the catalytic composition as a halide of the
hydrogenation metal, or as a halogen acid or a halide salt.
The catalyst of the present invention, that is, the catalyst
comprising a hydrogenation component, a small amount of rhenium,
and a small amount of gallium on a solid catalytic support
comprising a porous refractory inorganic oxide, is suitable for the
conversion of petroleum hydrocarbon streams. In particular, it is
employed for the reforming of petroleum hydrocarbon naphthas and
those petroleum hydrocarbon streams boiling in the gasoline boiling
range. This catalyst is effective for converting the heavy
paraffins remaining in a reformate. Therefore, a preferred
embodiment of the process of the present invention is a process
which employs a first reforming catalyst in a first reforming zone
and the catalyst of the present invention as a second reforming
catalyst in a second reforming zone. Still more particularly, the
first reforming catalyst is employed in all of the reactors except
tha tail reactor and the second reforming catalyst is employed in
the tail reactor. For selected conditions and selected feedstocks,
it is contemplated that the first reforming zone could constitute
two or more reactors and the second reforming zone could constitute
at least one reactor. In an alternative embodiment of the process
of the present invention, the reforming system could comprise one
or more reactors containing the catalyst of the present invention
as a catalyst and making up a sole reaction zone. To this latter
embodiment, a partially-reformed naphtha would be the preferred
feedstock.
Therefore, according to one embodiment of the process of the
present invention, there is provided a process for reforming a
petroleum hydrocarbon stream, which process comprises contacting a
partially-reformed hydrocarbon stream in a reforming zone under
reforming conditions and in the presence of hydrogen with a
catalyst comprising a hydrogenation component, a small amount of
rhenium, and a small amount of gallium on a solid catalytic support
comprising a porous refractory inorganic oxide. In another
embodiment of the process of the present invention, the process
comprises contacting a petroleum hydrocarbon stream in a first
reforming zone under reforming conditions and in the presence of
hydrogen with a first reforming catalyst to produce a first
reformate and subsequently contacting said first reformate in a
second reforming zone under reforming conditions and in the
presence of hydrogen with a second reforming catalyst comprising a
hydrogenation component, a small amount of rhenium, and a small
amount of gallium on a solid catalytic support comprising a porous
refractory inorganic oxide. This latter embodiment is a process
wherein the first reforming zone comprises two or more reactors and
the second reforming zone comprises at least one reactor.
Typical operating conditions of the reforming process of the
present invention comprise an average catalyst temperature of about
700.degree.F. to about 1,050.degree.F., a pressure of about 50 psig
to about 1,000 psig, a weight hourly space velocity (WHSV) of about
0.5 to about 10 weight units of hydrocarbon per hour per weight
unit of catalyst, and a hydrogen addition rate of about 1,500
standard cubic feet per barrel (SCFB) to about 15,000 SCFB.
Preferred reforming conditions comprise an average catalyst
temperature of about 850.degree.F. to about 950.degree.F., a
pressure of about 50 psig to about 300 psig, a WHSV of about 1 to
about 8 weight units of hydrocarbon per hour per weight unit of
catalyst, and a hydrogen addition rate of about 3,000 SCFB to about
10,000 SCFB. These operating conditions are appropriate for each
reforming zone of the multiple-zone embodiment of the process of
the present invention.
The process of the present invention can be carried out in any of
the conventional types of equipment known to the art. One may, for
example, employ catalysts in the form of pills, pellets, granules,
broken fragments, or various special shapes, disposed as one or
more fixed beds within one or more reaction zones, and the charging
stock may be passed therethrough in the liquid, vapor, or mixed
phase, and in either upward or downward flow. Alternatively, the
catalysts may be in a suitable form for use in moving beds, in
which the charging stock and catalyst are preferably passed in
countercurrent flow; or in fluidized-solid processes, in which the
charging stock is passed upward through a turbulent bed of finely
divided catalyst; or in the suspensoid process, in which the
catalyst is slurried in the charging stock and the resulting
mixture is conveyed into the reaction zone. A fixed-bed reforming
process is exemplified by Ultra-forming (Petroleum Engineer, Vol.
XXVI, No. 4, April 1954, at page C-35). In a six-reactor unit with
the five fixed-bed reactors on oil and one fixed-bed reactor under
regeneration, when employing the multiple-zone embodiment, it is
convenient to employ the second reforming catalyst in the last
reactor and a mixture (or layers) of the first reforming catalyst
and the second reforming catalyst in the swing reactor. The
reaction products from any of the foregoing processes are removed
from the reaction zones and fractionated to recover the various
components thereof. The hydrogen and unconverted materials are
recycled as desired, the excess hydrogen produced in the reformer
conveniently being utilized in the hydrodesulfurization of the
feed.
Unwanted products in the reforming of petroleum hydrocarbon streams
are light hydrocarbon gases and coke. Such products and other
compounds, such as polynuclear aromatics and heavy hydrocarbons,
may result in coke. As the operation progresses, a substantial
amount of coke accumulates on the surface of each of the catalysts
resulting in an increasingly rapid rate of catalyst deactivation.
Consequently, the coke must be removed periodically from the
surface. Such coke removal may be accomplished through a coke-burn
treatment wherein the coked catalyst is contacted with an
oxygen-containing gas at selected temperatures. Typically, the gas
will contain oxygen within the range of about 1.0 volume percent to
about 21 volume percent. The concentration of oxygen in the gas
should be maintained at a level which will not result in the
production of temperatures that will be in excess of
1,100.degree.F., preferably, in excess of 1,050.degree.F.
The process of the present invention may be employed typically as a
semi-regenerative reforming process or as a regenerative or cyclic
process.
In a semi-regnerative reforming system, the flow of hydrocarbons is
stopped to all of the reactors and the catalyst in each of the
reactors is regenerated. In a regenerative or cyclic reforming
system, one of the reactors is removed from the system and is
replaced by an auxiliary reactor. Reforming of petroleum
hydrocarbons continues in such a system while catalyst in the
reactor that has been removed from the system is regenerated. The
auxiliary reactor is known as a swing reactor. It is contemplated
in the process of the present invention that the multiple-reactor
system may include either one swing reactor or two swing reactors.
When two swing reactors are being employed, one will contain the
catalyst that is employed in the first reforming zone of the
process and will be used to replace a reactor in the first
reforming zone. The other will contain the catalyst that is
employed in the second reforming zone and will be used to replace a
reactor in the second reforming zone.
Either the first reforming catalyst or the second reforming
catalyst that is employed in the multiple-zone embodiment of the
process of the present invention is capable of being regenerated
and is capable of withstanding the conditions employed in the
regeneration treatment.
A preferred embodiment of the process of the present invention is
depicted in the accompanying FIG. 1. This figure is a simplified
schematic flow diagram of the preferred embodiment. It does not
include certain auxiliary equipment, such as heat exchangers,
valves pumps, compressors, and associated equipment, which would be
needed in various places along the flow path of the process in
addition to the pump and compressor that are depicted in the
drawing. Such additional auxiliary equipment and its location
requirements would be quickly recognized by one having ordinary
skill in the art. Therefore, such equipment is not shown in the
figure.
In the embodiment represented in FIG. 1, a naphtha heart cut,
having a boiling range of about 160.degree.F. to about
400.degree.F., preferably, about 180.degree.F. to about
380.degree.F., is obtained from source 10. This feedstock is passed
through line 11 into pump 12, which pumps the hydrocarbons through
line 13. Hydrogen-containing recycle gas is introduced into line 13
via line 14 to be mixed with the hydrocarbons in line 13. The
resulting hydrogen-hydrocarbon mixture passes through line 13,
furnace 15, and line 16 into the top of reactor 17. The material is
introduced into reactor 17 at a temperature of about 940.degree.F.
to about 980.degree.F. The outlet temperature of reactor 17 is
approximately 800.degree.F. and the pressure in reactor 17 is
within the range of about 160 psig to about 320 psig.
The effluent from reactor 17 passes through line 18, furnace 19,
and line 20 into the top of reactor 21. Sufficient heat is
introduced into this hydrogen-hydrocarbon stream by furnace 19 so
that the temperature at the inlet of reactor 21 is about
960.degree.F. to about 1,000.degree.F. The outlet temperature of
reactor 21 is approximately 855.degree.F. and the pressure in
reactor 21 is within the range of about 140 psig to about 300
psig.
The effluent from reactor 21 passes through line 22, furnace 23,
and line 24 into the top of reactor 25. This effluent is heated in
furnace 23 so that the inlet temperature of reactor 25 is about
960.degree.F. to about 1,000.degree.F. The outlet temperature of
reactor 25 is approximately 940.degree.F. and the pressure in
reactor 25 is within the range of about 120 psig to about 280
psig.
The effluent from reactor 25 passes through line 26, furnace 27,
and line 28 into the top of reactor 29. This hydrocarbon effluent
is heated in furnace 27 so that the inlet temperature of reactor 29
is about 980.degree.F. to about 1,020.degree.F. The outlet
temperature of reactor 29 is about 950.degree.F. and the pressure
in reactor 29 is within the range of about 100 psig to about 260
psig.
Reactors 17, 21, and 25 all contain a catalyst comprising platinum
and chloride on a support of catalytically active alumina. The
catalyst may be promoted by a small amount of rhenium. In general,
the catalyst contains 0.1 to about 2 wt.% platinum and 0.1 to 5
wt.% chloride, preferably, 0.4 to 1 wt.% chloride. The fourth
reactor, or tail reactor, in the system contains a second reforming
catalyst comprising about 0.1 wt.% to about 1 wt.% platinum, about
0.1 wt.% to about 1 wt.% rhenium, about 0.1 wt.% to about 1 wt.%
gallium, and about 0.1 wt.% to about 1 wt.% chloride on a
gamma-alumina, each amount being based upon the weight of the
second reforming catalyst.
Not shown in the figure is a fifth reactor, which reactor contains
a mixture or layers of the two catalysts. This additional reactor
is employed as a swing reactor for each of the four reactors in
this system when the catalyst in a particular reactor has become
deactivated and must be regenerated. The reactor containing this
deactivated catalyst is removed from the system and is replaced by
the swing reactor in order that the reforming system may be
operated continuously, even though the deactivated catalyst has
been removed from the system and is being regenerated.
The hydrogen-to-hydrocarbon ratio and the WHSV employed in the
various reactors fall within the respective ranges of values as
expressed hereinabove.
The effluent from reactor 29 passes through line 30, water cooler
31, and line 32 into gas-liquid separator 33. Gas-liquid separator
33 is operated at a pressure of about 80 psig to about 240 psig and
at temperatures of about 100.degree.F. Liquid product is removed
from separator 33 through line 34 to be sent to a suitable product
recovery system from which a high-octane-number product is
obtained. Gaseous material is removed from separator 33 through
line 35. A portion of this gas is removed from the system through
line 36 to be used at other refinery units. The remainder of the
hydrogen-hydrocarbon gas in line 35 is compressed by compressor 37
to be sent through lines 38 and 14 as hydrogen-hydrocarbon recycle
gas. When necessary, make-up hydrogen gas may be introduced into
the system from source 39 via line 40.
A second embodiment of the process of the present invention may be
represented also by the simplified schematic flow diagram depicted
in FIG. 1. In this second embodiment, each of the four reactors,
including reactor 29, contains the catalytic composition of the
present invention. Even the swing reactor (not shown) employs this
catalyst, which comprises about 0.1 wt.% to about 1 wt.% platinum,
about 0.1 wt.% to about 1 wt.% rhenium, about 0.1 wt.% to about 1
wt.% gallium, and about 0.1 wt.% to about 1 wt.% chloride on a
gamma-alumina, each amount being based upon the weight of the
catalyst. The operating conditions employed in this embodiment fall
within the ranges of values set froth hereinabove. In this latter
embodiment, either a virgin naphtha or a mildly-reformed or
partially-reformed hydrocarbon stream may be employed as the
hydrocarbon feedstock.
The above-described embodiments and the following examples are
presented herein to facilitate the understanding of the present
invention. These are presented for the purpose of illustration only
and are not intended to limit the scope of the present
invention.
EXAMPLE I
Representative samples of two commerically-prepared reforming
catalysts were obtained from the American Cyanamid Company. The
first of these, hereinafter identified as Catalyst A, contained
0.74 wt.% platinum and 0.77 wt.% chloride on a gamma-alumina. The
second, hereinafter identified as Catalyst B, contained 0.56 wt.%
platinum, 0.51 wt.% rhenium, and 0.79 wt.% chloride on a
gamma-alumina support.
Catalyst C was prepared in the laboratory to contain 1 wt.%
gallium, based upon the total weight of the catalytic composition.
A 50-gram smaple of Catalyst A was impregnated with 50 cc of a
solution that had been prepared by dissolving 3 grams of gallium
nitrate, Ga(NO.sub.3).sub.3.sup.. 9H.sub.2 O, in distilled water.
The impregnated material was then dried in air for 3 hours at a
temperature of 250.degree.F. and subsequently calcined in air for 3
hours at a temperature of 1,000.degree.F. For this catalyst
preparation and for those described hereinafter, the material to be
impregnated had been pulverized previously to a 20-to-40-mesh
material, that is, the material was of a particle size that would
pass through a 20-mesh screen but would be retained upon a 40-mesh
screen (U.S. Sieve Series). Unless otherwise stated, for each
catalyst preparation described herein, the drying and calcining
were carried out under the above-described conditions and at an air
rate of 1.5 cubic feet per hour. Catalyst C was found to contain
0.34 wt.% chloride.
Catalyst D was prepared in the laboratory to contain 1 wt.%
gallium. A 50-gram portion of a commercially-prepared reforming
catalyst, obtained from the American Cyanamid Company and
containing 0.43 wt.% platinum and 0.42 wt.% chloride on a
gamma-alumina, was impregnated with 50 cc of a solution of gallium
nitrate. This solution had been prepared by dissolving 3 grams of
gallium nitrate in sufficient distilled water to make 50 cc of
solution. The impregnated material was dried and calcined. Catalyst
D contained 0.30 wt.% chloride.
Catalyst E was prepared to contain 1 wt.% gallium. A 50-gram
portion of the commercially-prepared catalyst that was employed in
the preparation of Catalyst D was impregnated with a solution that
had been prepared by dissolving 3 grams of gallium nitrate and
1.345 grams of 37.5% hydrochloric acid in 50 ml. of distilled
water. The impregnated material was dried and calcined. Catalyst E
was found to contain 0.61 wt.% chloride.
Catalyst F was prepared to contain 1 wt.% gallium and about 0.58
wt.% rhenium. A 50-gram portion of Catalyst B was impregnated with
50 cc of a solution prepared by dissolving 3 grams of gallium
nitrate in sufficient distilled water to make 50 cc of solution.
The impregnated material was dried overnight at a temperature pf
250.degree.F. and was subsequently calcined. The catalyst contained
0.41 wt.% chloride.
EXAMPLE II
Each of the catalysts that was prepared or obtained in Example I
was tested for its ability to reform a partially-reformed naphtha.
The various properties of this feedstock are presented hereinbelow
in Table I.
TABLE I
FEEDSTOCK PROPERTIES
Gravity, .degree.API 48.9 Specific Gravity 0.7844 Research Octane
No. 87.4 ASTM Distillation .degree.F. IBP 118 10% 188 30 230 50 256
70 284 90 324 FBP 398 Composition, Vol.% Paraffins 43.8 Naphthenes
3.0 Aromatics 53.2 Sulfur, ppm 0.3 Nitrogen, ppm 0.4
The testing was carried out in a bench-scale test unit employing an
isothermal fixed bed of catalyst. The hydrocarbon feedstock and
bottled hydrogen (once-through) were mixed and the resulting
hydrogen-hydrocarbon mixture was charged to a reactor having an
inside diameter of 0.622 inch. The reactor, which was 20 inches
long, was immersed in a heating bath containing DuPont HITEC. The
hydrocarbon feed was pumped by a positive-displacement Ruska pump.
The effluent from the reactor was sent to conventional product
handling and recovery equipment. Liquid sampels for octane analysis
were collected overnight (for 17 hours) at ambient temperature.
Material balances were obtained from smaples collected for one hour
with a dry ice knock-back and such samples were analyzed by gas
chromatographic techniques.
Each catalyst sample that was charged to the reactor was in the
form of 20-40-mesh material (U.S. Sieve Series). After the reactor
was placed in the test unit the catalyst was pretreated by being
subjected to an air soak for one-half hour at an air rate of about
2 cubic feet per hour, a temperature of about 900.degree.F., and a
pressure of 200 psig. Subsequently, the catalyst was purged with
nitrogen and then reduced with hydrogen for one hour at the test
temperature and pressure. For the catalysts containing rhenium,
Catalyst B, and Catalyst F, a pre-sulfiding technique was also
employed. These catalysts were pre-sulfided with a gas mixture of 8
volume percent hydrogen sulfide in hydrogen at test temperature and
pressure before they were tested.
These tests were conducted at a pressure of 200 psig, a WHSV of
3.62, a kinetic average temperature of about 900.degree.F., and a
hydrogen addition rate of about 3,000 SCFB. In each case, 13 grams
of catalyst were employed. When the unit was placed on test, no
sampling was performed for the first 5 hours to permit the test to
line out.
The test results are presented in FIG. 2. The unleaded
C.sup.+.sub.5 research octane numbers which were obtained in the
tests were corrected to a temperature of 900.degree.F. and to an
initial chloride level on the catalyst of 0.74 wt.% chloride. These
corrections were made by use of emperical correlations. Please note
that the average performance of the catalysts that were promoted
with gallium is represented by a solid line, while the performances
of each of those catalysts are represented by broken lines. The
difference in platinum level between two catalysts would not
appreciably affect the performances of the two catalysts.
The results in FIG. 2 show that the test which employed Catalyst F,
i.e., an embodiment of the process of the present invention,
provided C.sup.+.sub.5 research octane numbers that were superior
to those tests which employed the other catalysts, namely,
Catalysts A, B, C, D, and E. These latter tests represented other
reforming processes. The C.sup.+.sub.5 liquid yield data obtained
from these tests in this bench-scale unit did not provide
sufficient differences between the tests to distinguish the yields
obtained with one catalyst from those obtained with another.
* * * * *