Molecular sieve abstract
The present invention relates to new molecular sieve SSZ-71 prepared
using a N-benzyl-14-diazabicyclo[2.2.2]octane cation as a structure-directing
agent, methods for synthesizing SSZ-71 and processes employing SSZ-71
in a catalyst.
Molecular sieve claims
1. A process for converting hydrocarbons comprising contacting
a hydrocarbonaceous feed at hydrocarbon converting conditions with
a catalyst comprising a molecular sieve produced by the method comprising:
(1) preparing an as-synthesized molecular sieve having a composition,
as synthesized and in the anhydrous state, in terms of mole ratios
as follows: YO.sub.2/WO.sub.d 15-.infin.M.sub.2/nYO.sub.2 0-0.03
Q/YO.sub.2 0.02-0.05 wherein Y is silicon, germanium or a mixture
thereof; W is zinc, titanium or mixtures thereof; d is 1 or 2 (i.e.,
d is 1 when W is divalent or 2 when W is tetravalent); M is an alkali
metal cation, alkaline earth metal cation or mixtures thereof; n
is the valence of M (i.e., 1 or 2); and Q is a N-benzyl-14-diazabicyclo[2.2.2]octane
cation, the as-synthesized molecular sieve having the X-ray diffraction
lines of Table I; (2) thermally treating the as-synthesized molecular
sieve at a temperature and for a time sufficient to remove the N-benzyl-14-diazabicyclo[2.2.2]octane
cation from the molecular sieve; and (3) optionally, replacing at
least part of the zinc and/or titanium with a metal selected from
the group consisting of aluminum, gallium, iron, boron, indium,
vanadium and mixtures thereof.
2. The process of claim 1 wherein the molecular sieve is predominantly
in the hydrogen form.
3. The process of claim 1 wherein the molecular sieve is substantially
free of acidity.
4. The process of claim 1 wherein the process is a hydrocracking
process comprising contacting the catalyst with a hydrocarbon feedstock
under hydrocracking conditions.
5. The process of claim 4 wherein the molecular sieve is predominantly
in the hydrogen form.
6. The process of claim 1 wherein the process is a dewaxing process
comprising contacting the catalyst with a hydrocarbon feedstock
under dewaxing conditions.
7. The process of claim 6 wherein the molecular sieve is predominantly
in the hydrogen form.
8. The process of claim 1 wherein the process is a process for
improving the viscosity index of a dewaxed product of waxy hydrocarbon
feeds comprising contacting the catalyst with a waxy hydrocarbon
feed under isomerization dewaxing conditions.
9. The process of claim 8 wherein the molecular sieve is predominantly
in the hydrogen form.
10. The process of claim 1 wherein the process is a process for
producing a C.sub.20+ lube oil from a C.sub.20+ olefin feed comprising
isomerizing said olefin feed under isomerization conditions over
the catalyst.
11. The process of claim 10 wherein the molecular sieve is predominantly
in the hydrogen form.
12. The process of claim 10 wherein the catalyst further comprises
at least one Group VIII metal.
13. The process of claim 1 wherein the process is a process for
catalytically dewaxing a hydrocarbon oil feedstock boiling above
about 350.degree. F. (177.degree. C.) and containing straight chain
and slightly branched chain hydrocarbons comprising contacting said
hydrocarbon oil feedstock in the presence of added hydrogen gas
at a hydrogen pressure of about 15-3000 psi (0.103-20.7 MPa) under
dewaxing conditions with the catalyst.
14. The process of claim 13 wherein the molecular sieve is predominantly
in the hydrogen form.
15. The process of claim 13 wherein the catalyst further comprises
at least one Group VIII metal.
16. The process of claim 13 wherein said catalyst comprises a layered
catalyst comprising a first layer comprising the molecular sieve
and at least one Group VIII metal, and a second layer comprising
an aluminosilicate zeolite which is more shape selective than the
molecular sieve of said first layer.
17. The process of claim 1 wherein the process is a process for
preparing a lubricating oil which comprises: hydrocracking in a
hydrocracking zone a hydrocarbonaceous feedstock to obtain an effluent
comprising a hydrocracked oil; and catalytically dewaxing said effluent
comprising hydrocracked oil at a temperature of at least about 400.degree.
F. (204.degree. C.) and at a pressure of from about 15 psig to about
3000 psig (0.103 to 20.7 MPa gauge) in the presence of added hydrogen
gas with the catalyst.
18. The process of claim 17 wherein the molecular sieve is predominantly
in the hydrogen form.
19. The process of claim 17 wherein the catalyst further comprises
at least one Group VIII metal.
20. The process of claim 1 wherein the process is a process for
isomerization dewaxing a raffinate comprising contacting said raffinate
in the presence of added hydrogen under isomerization dewaxing conditions
with the catalyst.
21. The process of claim 20 wherein the molecular sieve is predominantly
in the hydrogen form.
22. The process of claim 20 wherein the catalyst further comprises
at least one Group VIII metal.
23. The process of claim 20 wherein the raffinate is bright stock.
24. The process of claim 1 wherein the process is a process for
increasing the octane of a hydrocarbon feedstock to produce a product
having an increased aromatics content comprising contacting a hydrocarbonaceous
feedstock which comprises normal and slightly branched hydrocarbons
having a boiling range above about 40.degree. C. and less than about
200.degree. C. under aromatic conversion conditions with the catalyst.
25. The process of claim 24 wherein the molecular sieve is substantially
free of acid.
26. The process of claim 24 wherein the molecular sieve contains
a Group VIII metal component.
27. The process of claim 1 wherein the process is a catalytic cracking
process comprising contacting a hydrocarbon feedstock in a reaction
zone under catalytic cracking conditions in the absence of added
hydrogen with the catalyst.
28. The process of claim 27 wherein the molecular sieve is predominantly
in the hydrogen form.
29. The process of claim 27 wherein the catalyst additionally comprises
a large pore crystalline cracking component.
30. The process of claim 1 wherein the process is an isomerization
process for isomerizing C.sub.4 to C.sub.7 hydrocarbons, comprising
contacting a feed having normal and slightly branched C.sub.4 to
C.sub.7 hydrocarbons under isomerizing conditions with the catalyst.
31. The process of claim 30 wherein the molecular sieve is predominantly
in the hydrogen form.
32. The process of claim 30 wherein the molecular sieve has been
impregnated with at least one Group VIII metal.
33. The process of claim 30 wherein the catalyst has been calcined
in a steam/air mixture at an elevated temperature after impregnation
of the Group VIII metal.
34. The process of claim 32 wherein the Group VIII metal is platinum.
35. The process of claim 1 wherein the process is a process for
alkylating an aromatic hydrocarbon which comprises contacting under
alkylation conditions at least a molar excess of an aromatic hydrocarbon
with a C.sub.2 to C.sub.20 olefin under at least partial liquid
phase conditions and in the presence of the catalyst.
36. The process of claim 35 wherein the molecular sieve is predominantly
in the hydrogen form.
37. The process of claim 35 wherein the olefin is a C.sub.2 to
C.sub.4 olefin.
38. The process of claim 37 wherein the aromatic hydrocarbon and
olefin are present in a molar ratio of about 4:1 to about 20:1
respectively.
39. The process of claim 37 wherein the aromatic hydrocarbon is
selected from the group consisting of benzene, toluene, ethylbenzene,
xylene, naphthalene, naphthalene derivatives, dimethyinaphthalene
or mixtures thereof.
40. The process of claim 1 wherein the process is a process for
transalkylating an aromatic hydrocarbon which comprises contacting
under transalkylating conditions an aromatic hydrocarbon with a
polyalkyl aromatic hydrocarbon under at least partial liquid phase
conditions and in the presence of the catalyst.
41. The process of claim 40 wherein the molecular sieve is predominantly
in the hydrogen form.
42. The process of claim 40 wherein the aromatic hydrocarbon and
the polyalkyl aromatic hydrocarbon are present in a molar ratio
of from about 1:1 to about 25:1 respectively.
43. The process of claim 40 wherein the aromatic hydrocarbon is
selected from the group consisting of benzene, toluene, ethylbenzene,
xylene, or mixtures thereof.
44. The process of claim 40 wherein the polyalkyl aromatic hydrocarbon
is a dialkylbenzene.
45. The process of claim 1 wherein the process is a process to
convert paraffins to aromatics which comprises contacting paraffins
under conditions which cause paraffins to convert to aromatics with
a catalyst comprising the molecular sieve and gallium, zinc, or
a compound of gallium or zinc.
46. The process of claim 1 wherein the process is a process for
isomerizing olefins comprising contacting said olefin under conditions
which cause isomerization of the olefin with the catalyst.
47. The process of claim 1 wherein the process is a process for
isomerizing an isomerization feed comprising an aromatic C.sub.8
stream of xylene isomers or mixtures of xylene isomers and ethylbenzene,
wherein a more nearly equilibrium ratio of ortho-, meta and para-xylenes
is obtained, said process comprising contacting said feed under
isomerization conditions with the catalyst.
48. The process of claim 1 wherein the process is a process for
oligomerizing olefins comprising contacting an olefin feed under
oligomerization conditions with the catalyst.
49. A process for converting oxygenated hydrocarbons comprising
contacting said oxygenated hydrocarbon under conditions to produce
liquid products with a catalyst comprising a molecular sieve having
a mole ratio greater than about 15 of an oxide of a first tetravalent
element to an oxide of a second tetravalent element which is different
from said first tetravalent element, trivalent element, pentavalent
element or mixture thereof and having, after calcination, the X-ray
diffraction lines of Table II.
50. The process of claim 49 wherein the oxygenated hydrocarbon
is a lower alcohol.
51. The process of claim 50 wherein the lower alcohol is methanol.
52. The process of claim 1 wherein the process is a process for
the production of higher molecular weight hydrocarbons from lower
molecular weight hydrocarbons comprising the steps of: (a) introducing
into a reaction zone a lower molecular weight hydrocarbon-containing
gas and contacting said gas in said zone under C.sub.2+ hydrocarbon
synthesis conditions with the catalyst and a metal or metal compound
capable of converting the lower molecular weight hydrocarbon to
a higher molecular weight hydrocarbon; and (b) withdrawing from
said reaction zone a higher molecular weight hydrocarbon-containing
stream.
53. The process of claim 52 wherein the metal or metal compound
comprises a lanthanide or actinide metal or metal compound.
54. The process of claim 52 wherein the lower molecular weight
hydrocarbon is methane.
55. A catalyst composition for promoting polymerization of 1-olefins,
said composition comprising (A) a molecular sieve produced by the
method comprising: (1) preparing an as-synthesized molecular sieve
having a composition, as synthesized and in the anhydrous state,
in terms of mole ratios as follows: YO.sub.2/WO.sub.d 15-.infin.M.sub.2/nYO.sub.2
0-0.03 Q/YO.sub.2 0.02-0.05 wherein Y is silicon, germanium or a
mixture thereof; W is zinc, titanium or mixtures thereof; d is 1
or 2 (i.e., d is 1 when W is divalent or 2 when W is tetravalent);
M is an alkali metal cation, alkaline earth metal cation or mixtures
thereof; n is the valence of M (i.e., 1 or 2); and Q is a N-benzyl-14-diazabicyclo[2.2.2]octane
cation, the as-synthesized molecular sieve having the X-ray diffraction
lines of Table I; (2) thermally treating the as-synthesized molecular
sieve at a temperature and for a time sufficient to remove the N-benzyl-14-diazabicyclo[2.2.2]octane
cation from the molecular sieve; and (3) optionally, replacing at
least part of the zinc and/or titanium with a metal selected from
the group consisting of aluminum, gallium, iron, boron, indium,
vanadium and mixtures thereof.; and (B) an organotitanium or organochromium
compound.
56. The process of claim 1 wherein the process is a process for
polymerizing 1-olefins, which process comprises contacting 1-olefin
monomer with a catalytically effective amount of a catalyst composition
comprising (A) a molecular sieve produced by the method comprising:
(1) preparing an as-synthesized molecular sieve having a composition,
as synthesized and in the anhydrous state, in terms of mole ratios
as follows: YO.sub.2/WO.sub.d 15-.infin.M.sub.2/nYO.sub.2 0-0.03
Q/YO.sub.2 0.02-0.05 wherein Y is silicon, germanium or a mixture
thereof; W is zinc, titanium or mixtures thereof; d is 1 or 2 (i.e.,
d is 1 when W is divalent or 2 when W is tetravalent); M is an alkali
metal cation, alkaline earth metal cation or mixtures thereof; n
is the valence of M (i.e., 1 or 2); and Q is a N-benzyl-14-diazabicyclo[2.2.2]octane
cation, the as-synthesized molecular sieve having the X-ray diffraction
lines of Table I; (2) thermally treating the as-synthesized molecular
sieve at a temperature and for a time sufficient to remove the N-benzyl-14-diazabicyclo[2.2.2]octane
cation from the molecular sieve; and (3) optionally, replacing at
least part of the zinc and/or titanium with a metal selected from
the group consisting of aluminum, gallium, iron, boron, indium,
vanadium and mixtures thereof.; and (B) an organotitanium or organochromium
compound under polymerization conditions which include a temperature
and pressure suitable for initiating and promoting the polymerization
reaction.
57. The process of claim 56 wherein the 1-olefin monomer is ethylene.
58. The process of claim 1 wherein the process is a process for
hydrogenating a hydrocarbon feed containing unsaturated hydrocarbons,
the process comprising contacting the feed with hydrogen under conditions
which cause hydrogenation with the catalyst.
59. The process of claim 58 wherein the catalyst contains metals,
salts or complexes wherein the metal is selected from the group
consisting of platinum, palladium, rhodium, iridium or combinations
thereof, or the group consisting of nickel, molybdenum, cobalt,
tungsten, titanium, chromium, vanadium, rhenium, manganese and combinations
thereof.
60. A process for hydrotreating a hydrocarbon feedstock comprising
contacting the feedstock with a hydrotreating catalyst and hydrogen
under hydrotreating conditions, wherein the catalyst comprises a
molecular sieve produced by the method comprising: (1) preparing
an as-synthesized molecular sieve having a composition, as synthesized
and in the anhydrous state, in terms of mole ratios as follows:
YO.sub.2/WO.sub.d 15-.infin.M.sub.2/nYO.sub.2 0-0.03 Q/YO.sub.2
0.02-0.05 wherein Y is silicon, germanium or a mixture thereof;
W is zinc, titanium or mixtures thereof; d is 1 or 2 (i.e., d is
1 when W is divalent or 2 when W is tetravalent); M is an alkali
metal cation, alkaline earth metal cation or mixtures thereof; n
is the valence of M (i.e., 1 or 2); and Q is a N-benzyl-14-diazabicyclo[2.2.2]octane
cation, the as-synthesized molecular sieve having the X-ray diffraction
lines of Table I; (2) thermally treating the as-synthesized molecular
sieve at a temperature and for a time sufficient to remove the N-benzyl-14-diazabicyclo[2.2.2]octane
cation from the molecular sieve; and (3) optionally, replacing at
least part of the zinc and/or titanium with a metal selected from
the group consisting of aluminum, gallium, iron, boron, indium,
vanadium and mixtures thereof.
61. The process of claim 60 wherein the catalyst contains a Group
VIII metal or compound, a Group VI metal or compound or combinations
thereof.
Molecular sieve description
[0001] This application claims the benefit under 35 USC 119 of
Provisional Application No. 60/639213 filed Dec. 23 2004.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to new molecular sieve SSZ-71
a method for preparing SSZ-71 using a N-benzyl-14-diazabicyclo[2.2.2]octane
cation as a structure directing agent and the use of SSZ-71 in catalysts
for, e.g., hydrocarbon conversion reactions.
[0004] 2. State of the Art
[0005] Because of their unique sieving characteristics, as well
as their catalytic properties, crystalline molecular sieves and
zeolites are especially useful in applications such as hydrocarbon
conversion, gas drying and separation. Although many different crystalline
molecular sieves have been disclosed, there is a continuing need
for new zeolites with desirable properties for gas separation and
drying, hydrocarbon and chemical conversions, and other applications.
New zeolites may contain novel internal pore architectures, providing
enhanced selectivities in these processes.
[0006] Crystalline aluminosilicates are usually prepared from aqueous
reaction mixtures containing alkali or alkaline earth metal oxides,
silica, and alumina. Crystalline borosilicates are usually prepared
under similar reaction conditions except that boron is used in place
of aluminum. By varying the synthesis conditions and the composition
of the reaction mixture, different zeolites can often be formed.
SUMMARY OF THE INVENTION
[0007] The present invention is directed to a family of molecular
sieves with unique properties, referred to herein as "molecular
sieve SSZ-71" or simply "SSZ-71". Preferably, SSZ-71
is in its silicate, zincosilicate, aluminosilicate, titanosilicate,
germanosilicate, vanadosilicate, ferrosilicate or borosilicate form.
The term "silicate" refers to a molecular sieve having
a high mole ratio of silicon oxide relative to aluminum oxide, preferably
a mole ratio greater than 100 including molecular sieves comprised
entirely of silicon oxide. As used herein, the term "zincosilicate"
refers to a molecular sieve containing both zinc oxide and silicon
oxide. The term "aluminosilicate" refers to a molecular
sieve containing both aluminum oxide and silicon oxide and the term
"borosilicate" refers to a molecular sieve containing
oxides of both boron and silicon.
[0008] In accordance with the present invention there is provided
a process for converting hydrocarbons comprising contacting a hydrocarbonaceous
feed at hydrocarbon converting conditions with a catalyst comprising
the molecular sieve of this invention. The molecular sieve may be
predominantly in the hydrogen form. It may also be substantially
free of acidity. The invention includes such a process wherein the
molecular sieve is a molecular sieve produced by the method comprising:
[0009] (1) preparing an as-synthesized molecular sieve having a
composition, as synthesized and in the anhydrous state, in terms
of mole ratios as follows: YO.sub.2/WO.sub.d 15-.infin.M.sub.2/nYO.sub.2
0-0.03 Q/YO.sub.2 0.02-0.05 wherein Y is silicon, germanium or a
mixture thereof; W is zinc, titanium or mixtures thereof; d is 1
or 2 (i.e., d is 1 when W is divalent or 2 when W is tetravalent);
M is an alkali metal cation, alkaline earth metal cation or mixtures
thereof; n is the valence of M (i.e., 1 or 2); and Q is a N-benzyl-14-diazabicyclo[2.2.2]octane
cation, the as-synthesized molecular sieve having the X-ray diffraction
lines of Table I; [0010] (2) thermally treating the as-synthesized
molecular sieve at a temperature (e.g., about 200.degree. C. to
about 800.degree. C.) and for a time sufficient to remove the N-benzyl-14-diazabicyclo[2.2.2]octane
cation from the molecular sieve; and [0011] (3) optionally, replacing
at least part of the zinc and/or titanium with a metal selected
from the group consisting of aluminum, gallium, iron, boron, indium,
vanadium and mixtures thereof.
[0012] Further provided by the present invention is a hydrocracking
process comprising contacting a hydrocarbon feedstock under hydrocracking
conditions with a catalyst comprising the molecular sieve of this
invention, preferably predominantly in the hydrogen form.
[0013] This invention also includes a dewaxing process comprising
contacting a hydrocarbon feedstock under dewaxing conditions with
a catalyst comprising the molecular sieve of this invention, preferably
predominantly in the hydrogen form.
[0014] The present invention also includes a process for improving
the viscosity index of a dewaxed product of waxy hydrocarbon feeds
comprising contacting the waxy hydrocarbon feed under isomerization
dewaxing conditions with a catalyst comprising the molecular sieve
of this invention, preferably predominantly in the hydrogen form.
[0015] The present invention further includes a process for producing
a C.sub.20+ lube oil from a C.sub.20+ olefin feed comprising isomerizing
said olefin feed under isomerization conditions over a catalyst
comprising the molecular sieve of this invention. The molecular
sieve may be predominantly in the hydrogen form. The catalyst may
contain at least one Group VIII metal.
[0016] In accordance with this invention, there is also provided
a process for catalytically dewaxing a hydrocarbon oil feedstock
boiling above about 350.degree. F. (177.degree. C.) and containing
straight chain and slightly branched chain hydrocarbons comprising
contacting said hydrocarbon oil feedstock in the presence of added
hydrogen gas at a hydrogen pressure of about 15-3000 psi (0.103-20.7
MPa) with a catalyst comprising the molecular sieve of this invention,
preferably predominantly in the hydrogen form. The catalyst may
contain at least one Group VIII metal. The catalyst may be a layered
catalyst comprising a first layer comprising the molecular sieve
of this invention, and a second layer comprising an aluminosilicate
zeolite which is more shape selective than the molecular sieve of
said first layer. The first layer may contain at least one Group
VIII metal.
[0017] Also included in the present invention is a process for
preparing a lubricating oil which comprises hydrocracking in a hydrocracking
zone a hydrocarbonaceous feedstock to obtain an effluent comprising
a hydrocracked oil, and catalytically dewaxing said effluent comprising
hydrocracked oil at a temperature of at least about 400.degree.
F. (204.degree. C.) and at a pressure of from about 15 psig to about
3000 psig (0.103-20.7 Mpa gauge)in the presence of added hydrogen
gas with a catalyst comprising the molecular sieve of this invention.
The molecular sieve may be predominantly in the hydrogen form. The
catalyst may contain at least one Group VIII metal.
[0018] Further included in this invention is a process for isomerization
dewaxing a raffinate comprising contacting said raffinate in the
presence of added hydrogen with a catalyst comprising the molecular
sieve of this invention. The raffinate may be bright stock, and
the molecular sieve may be predominantly in the hydrogen form. The
catalyst may contain at least one Group VIII metal.
[0019] Also included in this invention is a process for increasing
the octane of a hydrocarbon feedstock to produce a product having
an increased aromatics content comprising contacting a hydrocarbonaceous
feedstock which comprises normal and slightly branched hydrocarbons
having a boiling range above about 40.degree. C. and less than about
200.degree. C., under aromatic conversion conditions with a catalyst
comprising the molecular sieve of this invention made substantially
free of acidity by neutralizing said molecular sieve with a basic
metal. Also provided in this invention is such a process wherein
the molecular sieve contains a Group VIII metal component.
[0020] Also provided by the present invention is a catalytic cracking
process comprising contacting a hydrocarbon feedstock in a reaction
zone under catalytic cracking conditions in the absence of added
hydrogen with a catalyst comprising the molecular sieve of this
invention, preferably predominantly in the hydrogen form. Also included
in this invention is such a catalytic cracking process wherein the
catalyst additionally comprises a large pore crystalline cracking
component.
[0021] This invention further provides an isomerization process
for isomerizing C.sub.4 to C.sub.7 hydrocarbons, comprising contacting
a feed having normal and slightly branched C.sub.4 to C.sub.7 hydrocarbons
under isomerizing conditions with a catalyst comprising the molecular
sieve of this invention, preferably predominantly in the hydrogen
form. The molecular sieve may be impregnated with at least one Group
VIII metal, preferably platinum. The catalyst may be calcined in
a steam/air mixture at an elevated temperature after impregnation
of the Group VIII metal.
[0022] Also provided by the present invention is a process for
alkylating an aromatic hydrocarbon which comprises contacting under
alkylation conditions at least a molar excess of an aromatic hydrocarbon
with a C.sub.2 to C.sub.20 olefin under at least partial liquid
phase conditions and in the presence of a catalyst comprising the
molecular sieve of this invention, preferably predominantly in the
hydrogen form. The olefin may be a C.sub.2 to C.sub.4 olefin, and
the aromatic hydrocarbon and olefin may be present in a molar ratio
of about 4:1 to about 20:1 respectively. The aromatic hydrocarbon
may be selected from the group consisting of benzene, toluene, ethylbenzene,
xylene, naphthalene, naphthalene derivatives, dimethylnaphthalene
or mixtures thereof.
[0023] Further provided in accordance with this invention is a
process for transalkylating an aromatic hydrocarbon which comprises
contacting under transalkylating conditions an aromatic hydrocarbon
with a polyalkyl aromatic hydrocarbon under at least partial liquid
phase conditions and in the presence of a catalyst comprising the
molecular sieve of this invention, preferably predominantly in the
hydrogen form. The aromatic hydrocarbon and the polyalkyl aromatic
hydrocarbon may be present in a molar ratio of from about 1:1 to
about 25: 1 respectively.
[0024] The aromatic hydrocarbon may be selected from the group
consisting of benzene, toluene, ethylbenzene, xylene, or mixtures
thereof, and the polyalkyl aromatic hydrocarbon may be a dialkylbenzene.
[0025] Further provided by this invention is a process to convert
paraffins to aromatics which comprises contacting paraffins under
conditions which cause paraffins to convert to aromatics with a
catalyst comprising the molecular sieve of this invention, said
catalyst comprising gallium, zinc, or a compound of gallium or zinc.
[0026] In accordance with this invention there is also provided
a process for isomerizing olefins comprising contacting said olefin
under conditions which cause isomerization of the olefin with a
catalyst comprising the molecular sieve of this invention.
[0027] Further provided in accordance with this invention is a
process for isomerizing an isomerization feed comprising an aromatic
C.sub.8 stream of xylene isomers or mixtures of xylene isomers and
ethylbenzene, wherein a more nearly equilibrium ratio of ortho-,
meta- and para-xylenes is obtained, said process comprising contacting
said feed under isomerization conditions with a catalyst comprising
the molecular sieve of this invention.
[0028] The present invention further provides a process for oligomerizing
olefins comprising contacting an olefin feed under oligomerization
conditions with a catalyst comprising the molecular sieve of this
invention.
[0029] This invention also provides a process for converting oxygenated
hydrocarbons comprising contacting said oxygenated hydrocarbon with
a catalyst comprising the molecular sieve of this invention under
conditions to produce liquid products. The oxygenated hydrocarbon
may be a lower alcohol.
[0030] Further provided in accordance with the present invention
is a process for the production of higher molecular weight hydrocarbons
from lower molecular weight hydrocarbons comprising the steps of:
[0031] (a) introducing into a reaction zone a lower molecular weight
hydrocarbon-containing gas and contacting said gas in said zone
under C.sub.2+ hydrocarbon synthesis conditions with the catalyst
and a metal or metal compound capable of converting the lower molecular
weight hydrocarbon to a higher molecular weight hydrocarbon; and
[0032] (b) withdrawing from said reaction zone a higher molecular
weight hydrocarbon-containing stream.
[0033] The present invention further provides a process for hydrogenating
a hydrocarbon feed containing unsaturated hydrocarbons, the process
comprising contacting the feed and hydrogen under conditions which
cause hydrogenation with a catalyst comprising the molecular sieve
of this invention. The catalyst can also contain metals, salts or
complexes wherein the metal is selected from the group consisting
of platinum, palladium, rhodium, iridium or combinations thereof,
or the group consisting of nickel, molybdenum, cobalt, tungsten,
titanium, chromium, vanadium, rhenium, manganese and combinations
thereof.
[0034] The present invention also provides a catalyst composition
for promoting polymerization of 1-olefins, said composition comprising
[0035] (A) a molecular sieve produced by the method comprising:
[0036] (1) preparing an as-synthesized molecular sieve having a
composition, as synthesized and in the anhydrous state, in terms
of mole ratios as follows: YO.sub.2/WO.sub.d 15-.infin.M.sub.2/nYO.sub.2
0-0.03 Q/YO.sub.2 0.02-0.05 wherein Y is silicon, germanium or a
mixture thereof; W is zinc, titanium or mixtures thereof; d is 1
or 2 (i.e., d is 1 when W is divalent or 2 when W is tetravalent);
M is an alkali metal cation, alkaline earth metal cation or mixtures
thereof; n is the valence of M (i.e., 1 or 2); and Q is a N-benzyl-14-diazabicyclo[2.2.2]octane
cation, the as-synthesized molecular sieve having the X-ray diffraction
lines of Table I; [0037] (2) thermally treating the as-synthesized
molecular sieve at a temperature and for a time sufficient to remove
the N-benzyl-14-diazabicyclo[2.2.2]octane cation from the molecular
sieve; and [0038] (3) optionally, replacing at least part of the
zinc and/or titanium with a metal selected from the group consisting
of aluminum, gallium, iron, boron, indium, vanadium and mixtures
thereof.; and [0039] (B) an organotitanium or organochromium compound.
[0040] Also provided is a process for polymerizing 1-olefins, which
process comprises contacting 1-olefin monomer with a catalytically
effective amount of a catalyst composition comprising [0041] (A)
a molecular sieve produced by the method comprising: [0042] (1)
preparing an as-synthesized molecular sieve having a composition,
as synthesized and in the anhydrous state, in terms of mole ratios
as follows: YO.sub.2/WO.sub.d 15-.infin.M.sub.2/nYO.sub.2 0-0.03
Q/YO.sub.2 0.02-0.05 wherein Y is silicon, germanium or a mixture
thereof; W is zinc, titanium or mixtures thereof; d is 1 or 2 (i.e.,
d is 1 when W is divalent or 2 when W is tetravalent); M is an alkali
metal cation, alkaline earth metal cation or mixtures thereof; n
is the valence of M (i.e., 1 or 2); and Q is a N-benzyl-14-diazabicyclo[2.2.2]octane
cation, the as-synthesized molecular sieve having the X-ray diffraction
lines of Table I; [0043] (2) thermally treating the as-synthesized
molecular sieve at a temperature and for a time sufficient to remove
the N-benzyl-14-diazabicyclo[2.2.2]octane cation from the molecular
sieve; and [0044] (3) optionally, replacing at least part of the
zinc and/or titanium with a metal selected from the group consisting
of aluminum, gallium, iron, boron, indium, vanadium and mixtures
thereof.; and [0045] (B) an organotitanium or organochromium compound
under polymerization conditions which include a temperature and
pressure suitable for initiating and promoting the polymerization
reaction. The 1-olefin may be ethylene.
[0046] In accordance with this invention, there is also provided
a process for hydrotreating a hydrocarbon feedstock comprising contacting
the feedstock with a hydrotreating catalyst and hydrogen under hydrotreating
conditions, wherein the catalyst comprises the molecular sieve of
this invention.
DETAILED DESCRIPTION OF THE INVENTION
[0047] The present invention comprises a family of molecular sieves
designated herein "molecular sieve SSZ-71" or simply "SSZ-71".
In preparing SSZ-71 a N-benzyl-14-diazabicyclo[2.2.2]octane cation
(referred to herein as "benzyl DABCO") is used as a structure
directing agent ("SDA"), also known as a crystallization
template. The SDA useful for making SSZ-71 has the following structure:
[0048] The SDA cation is associated with an anion (X.sup.-) which
may be any anion that is not detrimental to the formation of the
molecular sieve. Representative anions include halogen, e.g., fluoride,
chloride, bromide and iodide, hydroxide, acetate, sulfate, tetrafluoroborate,
carboxylate, and the like. Hydroxide is the most preferred anion.
[0049] Benzyl DABCO and a method for making it are disclosed in
U.S. Pat. No. 5653956 issued Aug. 5 1997 to Zones.
[0050] SSZ-71 is prepared from a reaction mixture having the composition
shown in Table A below. TABLE-US-00001 TABLE A Reaction Mixture
Typical Preferred YO.sub.2/WO.sub.d >15 >30 OH--/YO.sub.2
0.10-0.50 0.20-0.30 Q/YO.sub.2 0.05-0.50 0.10-0.20 M.sub.2/n/YO.sub.2
0-0.40 0.10-0.25 H.sub.2O/YO.sub.2 10-80 15-45
where Y is silicon, germanium or a mixture thereof; W is zinc,
titanium or mixtures thereof; d is 1 or 2 (i.e., d is 1 when W is
divalent or 2 when W is tetravalent); M is an alkali metal cation,
alkaline earth metal cation or mixtures thereof; n is the valence
of M (i.e., 1 or 2); and Q is a N-benzyl-14-diazabicyclo[2.2.2]octane
cation.
[0051] In practice, SSZ-71 is prepared by a process comprising:
[0052] (a) preparing an aqueous solution containing sources of at
least one oxide capable of forming a molecular sieve and a benzyl
DABCO cation having an anionic counterion which is not detrimental
to the formation of SSZ-71; [0053] (b) maintaining the aqueous solution
under conditions sufficient to form SSZ-71; and [0054] (c) recovering
the SSZ-71.
[0055] SSZ-71 can be prepared as a zincosilicate or titanosilicate.
However, once the SSZ-71 is made, the zinc and/or titanium can be
replaced with other metals by techniques well known in the art.
Accordingly, SSZ-71 may comprise the molecular sieve and the SDA
in. combination with metallic and non-metallic oxides bonded in
tetrahedral coordination through shared oxygen atoms to form a cross-linked
three dimensional crystal structure. The metallic and non-metallic
oxides comprise one or a combination of oxides of (1) a first tetravalent
element(s), and (2) one or a combination of a divalent element(s),
trivalent element(s), pentavalent element(s), second tetravalent
element(s) different from the first tetravalent element(s) or mixture
thereof. The first tetravalent element(s) is preferably selected
from the group consisting of silicon, germanium and combinations
thereof. More preferably, the first tetravalent element is silicon.
The divalent element, trivalent element, pentavalent element and
second tetravalent element (which is different from the first tetravalent
element) is preferably selected from the group consisting of zinc,
aluminum, gallium, iron, boron, titanium, indium, vanadium and combinations
thereof. More preferably, the divalent or trivalent element or second
tetravalent element is zinc, aluminum, titanium or boron.
[0056] Silicon can be added as silicon oxide or Si(OC.sub.2H.sub.5).sub.4.
Zinc can be added as a zinc salt such as zinc acetate. Titanium
can be added as Ti(OC.sub.2H.sub.5).sub.4.
[0057] A source zeolite reagent may provide a source of metals.
In most cases, the source zeolite also provides a source of silica.
The source zeolite may also be used as a source of silica, with
additional silicon added using, for example, the conventional sources
listed above. Use of a source zeolite reagent is described in U.S.
Pat. No. 5225179 issued Jul. 6 1993 to Nakagawa entitled "Method
of Making Molecular Sieves", the disclosure of which is incorporated
herein by reference.
[0058] Typically, an alkali metal hydroxide and/or an alkaline
earth metal hydroxide, such as the hydroxide of sodium, potassium,
lithium, cesium, rubidium, calcium, strontium, barium and magnesium,
is used in the reaction mixture; however, this component can be
omitted so long as the equivalent basicity is maintained. The SDA
may be used to provide hydroxide ion. Thus, it may be beneficial
to ion exchange, for example, the halide to hydroxide ion, thereby
reducing or eliminating the alkali metal hydroxide quantity required.
The alkali metal cation or alkaline earth cation may be part of
the as-synthesized material, in order to balance valence electron
charges therein.
[0059] The reaction mixture is maintained at an elevated temperature
until the crystals of the SSZ-71 are formed. The hydrothermal crystallization
is usually conducted under autogenous pressure, at a temperature
between 100.degree. C. and 200.degree. C., preferably between 135.degree.
C. and 160.degree. C. The crystallization period is typically greater
than 1 day and preferably from about 3 days to about 20 days.
[0060] Optionally, the molecular sieve is prepared using mild stirring
or agitation.
[0061] During the hydrothermal crystallization step, the SSZ-71
crystals can be allowed to nucleate spontaneously from the reaction
mixture. The use of SSZ-71 or SSZ-42 (disclosed in U.S. Pat. No.
5653956 issued Aug. 5 1997 to Zones) crystals as seed material
can be advantageous in decreasing the time necessary for complete
crystallization to occur. In addition, seeding can lead to an increased
purity of the product obtained by promoting the nucleation and/or
formation of SSZ-71 over any undesired phases. When used as seeds,
as-synthesized SSZ-71 or SSZ-42 crystals (containing the SDA) are
added in an amount between 0.1 and 10% of the weight of first tetravalent
element oxide, e.g. silica, used in the reaction mixture.
[0062] Once the molecular sieve crystals have formed, the solid
product is separated from the reaction mixture by standard mechanical
separation techniques such as filtration. The crystals are water-washed
and then dried, e.g., at 90.degree. C. to 150.degree. C. for from
8 to 24 hours, to obtain the as-synthesized SSZ-71 crystals. The
drying step can be performed at atmospheric pressure or under vacuum.
[0063] SSZ-71 as prepared has a mole ratio of an oxide selected
from silicon oxide, germanium oxide and mixtures thereof to an oxide
selected from zinc oxide, titanium oxide and mixtures thereof greater
than about 15. SSZ-71 further has a composition, as synthesized
(i.e., prior to calcination of the SSZ-71) and in the anhydrous
state, in terms of mole ratios, shown in Table B below. TABLE-US-00002
TABLE B As-Synthesized SSZ-71 YO.sub.2/WO.sub.d >15 M.sub.2/n/YO.sub.2
0-0.03 Q/YO.sub.2 0.02-0.05
where Y, W, d, M, n and Q are as defined above.
[0064] SSZ-71 can be made with a mole ratio of YO.sub.2/WO.sub.d
of .infin., i.e., there is essentially no WO.sub.d present in the
SSZ-71. In this case, the SSZ-71 would be an all-silica material
or a germanosilicate. If SSZ-71 is prepared as a zincosilicate,
the zinc can be removed and replaced with metal atoms by techniques
known in the art. See, for example, U.S. Pat. No. 6117411 issued
Sep. 12 2000 to Takewaki et al. Metals such as aluminum, gallium,
iron, boron, titanium, indium, vanadium and mixtures thereof may
be added in this manner.
[0065] It is believed that SSZ-71 is comprised of a new framework
structure or topology which is characterized by its X-ray diffraction
pattern. SSZ-71 as-synthesized, has a structure whose X-ray powder
diffraction pattern exhibit the characteristic lines shown in Table
I and Table II and is thereby distinguished from other molecular
sieves. The XRD data shown in Table I and IA was obtained from a
sample of SSZ-71 prepared in the presence of sodium hydroxide. The
XRD data shown in Table II and IIA was obtained from a sample of
SSZ-71 prepared in the presence of strontium hydroxide. TABLE-US-00003
TABLE I As-Synthesized Zn-SSZ-71 Prepared with NaOH 2 Theta.sup.(a)
d-spacing (Angstroms) Relative Intensity.sup.(b) 5.64 15.7 S 8.65
10.2 S 13.65 6.49 M 17.06 5.20 M 20.32 4.37 M 20.64 4.30 VS 23.12
3.85 M 24.08 3.70 VS 26.15 3.41 M 26.57 3.35 M .sup.(a).+-.0.15
.sup.(b)The X-ray patterns provided are based on a relative intensity
scale in which the strongest line in the X-ray pattern is assigned
a value of 100: W(weak) is less than 20; M(medium) is between 20
and 40; S(strong) is between 40 and 60; VS(very strong) is greater
than 60.
[0066] Table IA below shows the X-ray powder diffraction lines
for as-synthesized Zn-SSZ-71 prepared with NaOH including actual
relative intensities. TABLE-US-00004 TABLE IA 2 Theta.sup.(a) d-spacing
(Angstroms) Relative Intensity (%) 5.64 15.7 60 8.65 10.2 57 11.40
7.8 5 11.95 7.4 7 13.11 6.75 7 13.65 6.49 21 14.34 6.18 5 17.06
5.20 29 17.84 4.97 4 18.23 4.87 10 18.84 4.71 12 19.49 4.55 18 20.32
4.37 37 20.64 4.30 100 21.55 4.12 16 22.03 4.03 16 23.12 3.85 34
24.08 3.70 62 25.29 3.52 20 25.52 3.49 20 26.15 3.41 29 26.57 3.35
33 27.15 3.28 9 28.55 3.13 18 30.00 2.98 8 30.80 2.90 5 31.68 2.82
10 32.45 2.76 5 33.16 2.70 7 34.92 2.57 11 35.61 2.52 14 36.90 2.44
12 38.82 2.32 14 40.26 2.24 12 .sup.(a).+-.0.15
[0067] TABLE-US-00005 TABLE II As-Synthesized Zn-SSZ-71 prepared
with Sr(OH).sub.2 2 Theta.sup.(a) d-spacing (Angstroms) Relative
Intensity.sup.(b) 5.65 15.6 VS 8.69 10.2 VS 16.99 5.22 S 19.52 4.55
M 20.60 4.31 VS 23.13 3.85 M 24.01 3.71 S 24.23 3.67 M 26.14 3.41
M 26.52 3.36 M .sup.(a).+-.0.15 .sup.(b)The X-ray patterns provided
are based on a relative intensity scale in which the strongest line
in the X-ray pattern is assigned a value of 100: W(weak) is less
than 20; M(medium) is between 20 and 40; S(strong) is between 40
and 60; VS(very strong) is greater than 60.
[0068] Table IIA below shows the X-ray powder diffraction lines
for as-synthesized SSZ-71 (Zn-SSZ-71 prepared with Sr(OH).sub.2)
including actual relative intensities. TABLE-US-00006 TABLE IIA
2 Theta.sup.(a) d-spacing (Angstroms) Relative Intensity (%) 5.65
15.6 84 8.69 10.2 67 11.36 7.8 5 11.94 7.4 5 13.17 6.7 7 13.68 6.5
20 14.34 6.18 6 15.31 5.79 2 16.99 5.22 42 18.24 4.86 8 18.79 4.72
17 19.52 4.55 26 20.34 4.37 23 20.60 4.31 100 21.59 4.12 13 22.06
4.03 16 23.13 3.85 37 24.01 3.71 41 24.23 3.67 25 25.25 3.53 20
25.52 3.49 23 26.14 3.41 36 26.52 3.36 30 27.10 3.29 12 28.52 3.13
22 29.85 2.99 6 30.24 2.96 2 30.84 2.90 3 31.64 2.83 11 32.44 2.76
5 33.11 2.71 5 34.86 2.57 6 35.63 2.52 14 36.10 2.49 6 .sup.(a).+-.0.15
[0069] The X-ray powder diffraction patterns were determined by
standard techniques. The radiation was the K-alpha/doublet of copper.
The peak heights and the positions, as a function of 20 where 0
is the Bragg angle, were read from the relative intensities of the
peaks, and d, the interplanar spacing in Angstroms corresponding
to the recorded lines, can be calculated.
[0070] The variation in the scattering angle (two theta) measurements,
due to instrument error and to differences between individual samples,
is estimated at .+-.0.15 degrees.
[0071] The X-ray diffraction pattern of Table I is representative
of "as-synthesized" or "as-made" SSZ-71 molecular
sieves. Minor variations in the diffraction pattern can result from
variations in the silica-to-zinc or silica-to-titanium mole ratio
of the particular sample due to changes in lattice constants. In
addition, sufficiently small crystals will affect the shape and
intensity of peaks, leading to significant peak broadening.
[0072] The molecular sieve produced by exchanging the metal or
other cations present in the molecular sieve with various other
cations (such as H.sup.+ or NH.sub.4.sup.+) yields essentially the
same diffraction pattern, although again, there may be minor shifts
in the interplanar spacing and variations in the relative intensities
of the peaks. Notwithstanding these minor perturbations, the basic
crystal lattice remains unchanged by these treatments.
[0073] SSZ-71 can be used as-synthesized, but preferably will be
thermally treated (calcined). Usually, it is desirable to remove
the alkali metal cation by ion exchange and replace it with hydrogen,
ammonium, or any desired metal ion. The molecular sieve can also
be steamed; steaming helps stabilize the molecular sieve to attack
from acids.
[0074] The molecular sieve can be used in intimate combination
with hydrogenating components, such as tungsten, vanadium, molybdenum,
rhenium, nickel, cobalt, chromium, manganese, or a noble metal,
such as palladium or platinum, for those applications in which a
hydrogenation-dehydrogenation function is desired.
[0075] Metals may also be introduced into the molecular sieve by
replacing some of the cations in the molecular sieve with metal
cations via standard ion exchange techniques (see, for example,
U.S. Pat. No. 3140249 issued Jul. 7 1964 to Plank et al.; U.S.
Pat. No. 3140251 issued Jul. 7 1964 to Plank et al.; and U.S.
Pat. No. 3140253 issued Jul. 7 1964 to Plank et al.). Typical
replacing cations can include metal cations, e.g., rare earth, Group
IA, Group IIA and Group VIII metals, as well as their mixtures.
Of the replacing metallic cations, cations of metals such as rare
earth, Mn, Ca, Mg, Zn, Cd, Pt, Pd, Ni, Co, Ti, Al, Sn, and Fe are
particularly preferred.
[0076] The hydrogen, ammonium, and metal components can be ion-exchanged
into the SSZ-71. The SSZ-71 can also be impregnated with the metals,
or the metals can be physically and intimately admixed with the
SSZ-71 using standard methods known to the art.
[0077] Typical ion-exchange techniques involve contacting the synthetic
molecular sieve with a solution containing a salt of the desired
replacing cation or cations. Although a wide variety of salts can
be employed, chlorides and other halides, acetates, nitrates, and
sulfates are particularly preferred. The molecular sieve is usually
calcined prior to the ion-exchange procedure to remove the organic
matter present in the channels and on the surface, since this results
in a more effective ion exchange. Representative ion exchange techniques
are disclosed in a wide variety of patents including U.S. Pat. No.
3140249 issued on Jul. 7 1964 to Plank et al.; U.S. Pat. No.
3140251 issued on Jul. 7 1964 to Plank et al.; and U.S. Pat.
No. 3140253 issued on Jul. 7 1964 to Plank et al.
[0078] Following contact with the salt solution of the desired
replacing cation, the molecular sieve is typically washed with water
and dried at temperatures ranging from 65.degree. C. to about 200.degree.
C. After washing, the molecular sieve can be calcined in air or
inert gas at temperatures ranging from about 200.degree. C. to about
800.degree. C. for periods of time ranging from 1 to 48 hours, or
more, to produce a catalytically active product especially useful
in hydrocarbon conversion processes.
[0079] Regardless of the cations present in the synthesized form
of SSZ-71 the spatial arrangement of the atoms which form the basic
crystal lattice of the molecular sieve remains essentially unchanged.
[0080] SSZ-71 can be formed into a wide variety of physical shapes.
Generally speaking, the molecular sieve can be in the form of a
powder, a granule, or a molded product, such as extrudate having
a particle size sufficient to pass through a 2-mesh (Tyler) screen
and be retained on a 400-mesh (Tyler) screen. In cases where the
catalyst is molded, such as by extrusion with an organic binder,
the SSZ-71 can be extruded before drying, or, dried or partially
dried and then extruded.
[0081] SSZ-71 can be composited with other materials resistant
to the temperatures and other conditions employed in organic conversion
processes. Such matrix materials include active and inactive materials
and synthetic or naturally occurring zeolites as well as inorganic
materials such as clays, silica and metal oxides. Examples of such
materials and the manner in which they can be used are disclosed
in U.S. Pat. No. 4910006 issued May 20 1990 to Zones et al.,
and U.S. Pat. No. 5316753 issued May 31 1994 to Nakagawa, both
of which are incorporated by reference herein in their entirety.
Hydrocarbon Conversion Processes
[0082] SSZ-71 molecular sieves are useful in hydrocarbon conversion
reactions. Hydrocarbon conversion reactions are chemical and catalytic
processes in which carbon containing compounds are changed to different
carbon containing compounds. Examples of hydrocarbon conversion
reactions in which SSZ-71 is expected to be useful include hydrocracking,
dewaxing, catalytic cracking and olefin and aromatics formation
reactions. The catalysts are also expected to be useful in other
petroleum refining and hydrocarbon conversion reactions such as
isomerizing n-paraffins and naphthenes, polymerizing and oligomerizing
olefinic or acetylenic compounds such as isobutylene and butene-1
polymerization of 1-olefins (e.g., ethylene), reforming, isomerizing
polyalkyl substituted aromatics (e.g., m-xylene), and disproportionating
aromatics (e.g., toluene) to provide mixtures of benzene, xylenes
and higher methylbenzenes and oxidation reactions. Also included
are rearrangement reactions to make various naphthalene derivatives,
and forming higher molecular weight hydrocarbons from lower molecular
weight hydrocarbons (e.g., methane upgrading).
[0083] The SSZ-71 catalysts may have high selectivity, and under
hydrocarbon conversion conditions can provide a high percentage
of desired products relative to total products.
[0084] For high catalytic activity, the SSZ-71 molecular sieve
should be predominantly in its hydrogen ion form. Generally, the
molecular sieve is converted to its hydrogen form by ammonium exchange
followed by calcination. If the molecular sieve is synthesized with
a high enough ratio of SDA cation to sodium ion, calcination alone
may be sufficient. It is preferred that, after calcination, at least
80% of the cation sites are occupied by hydrogen ions and/or rare
earth ions. As used herein, "predominantly in the hydrogen
form" means that, after calcination, at least 80% of the cation
sites are occupied by hydrogen ions and/or rare earth ions.
[0085] SSZ-71 molecular sieves can be used in processing hydrocarbonaceous
feedstocks. Hydrocarbonaceous feedstocks contain carbon compounds
and can be from many different sources, such as virgin petroleum
fractions, recycle petroleum fractions, shale oil, liquefied coal,
tar sand oil, synthetic paraffins from NAO, recycled plastic feedstocks
and, in general, can be any carbon containing feedstock susceptible
to zeolitic catalytic reactions. Depending on the type of processing
the hydrocarbonaceous feed is to undergo, the feed can contain metal
or be free of metals, it can also have high or low nitrogen or sulfur
impurities. It can be appreciated, however, that in general processing
will be more efficient (and the catalyst more active) the lower
the metal, nitrogen, and sulfur content of the feedstock.
[0086] The conversion of hydrocarbonaceous feeds can take place
in any convenient mode, for example, in fluidized bed, moving bed,
or fixed bed reactors depending on the types of process desired.
The formulation of the catalyst particles will vary depending on
the conversion process and method of operation.
[0087] Other reactions which can be performed using the catalyst
of this invention containing a metal, e.g., a Group VIII metal such
platinum, include hydrogenation-dehydrogenation reactions, denitrogenation
and desulfurization reactions.
[0088] The following table indicates typical reaction conditions
which may be employed when using catalysts comprising SSZ-71 in
the hydrocarbon conversion reactions of this invention. Preferred
conditions are indicated in parentheses. TABLE-US-00007 Process
Temp., .degree. C. Pressure LHSV Hydrocracking 175-485 0.5-350 bar
0.1-30 Dewaxing 200-475 15-3000 psig, 0.1-20 (250-450) 0.103-20.7
Mpa (0.2-10) gauge (200-3000 1.38-20.7 Mpa gauge) Aromatics 400-600
atm.-10 bar 0.1-15 formation (480-550) Cat. Cracking 127-885 subatm.-.sup.1
0.5-50 (atm.-5 atm.) Oligomerization .sup. 232-649.sup.2 0.1-50
atm..sup.23 .sup. 0.2-50.sup.2 .sup. 10-232.sup.4 -- 0.05-20.sup.5
.sup. (27-204).sup.4 -- .sup. (0.1-10).sup.5 Paraffins to 100-700
0-1000 psig .sup. 0.5-40.sup.5 aromatics Condensation 260-538 0.5-1000
psig, .sup. 0.5-50.sup.5 of alcohols 0.00345-6.89 Mpa gauge Isomerization
93-538 50-1000 psig, .sup. 1-10 (204-315) 0.345-6.89 (1-4) Mpa gauge
Xylene .sup. 260-593.sup.2 0.5-50 atm..sup.2 .sup. 0.1-100.sup.5
isomerization .sup. (315-566).sup.2 (1-5 atm).sup.2 .sup. (0.5-50).sup.5
.sup. 38-371.sup.4 1-200 atm..sup.4 0.5-50 .sup.1Several hundred
atmospheres .sup.2Gas phase reaction .sup.3Hydrocarbon partial pressure
.sup.4Liquid phase reaction .sup.5WHSV
Other reaction conditions and parameters are provided below.
Hydrocracking
[0089] Using a catalyst which comprises SSZ-71 preferably predominantly
in the hydrogen form, and a hydrogenation promoter, heavy petroleum
residual feedstocks, cyclic stocks and other hydrocrackate charge
stocks can be hydrocracked using the process conditions and catalyst
components disclosed in the aforementioned U.S. Pat. No. 4910006
and U.S. Pat. No. 5316753.
[0090] The hydrocracking catalysts contain an effective amount
of at least one hydrogenation component of the type commonly employed
in hydrocracking catalysts. The hydrogenation component is generally
selected from the group of hydrogenation catalysts consisting of
one or more metals of Group VIB and Group VIII, including the salts,
complexes and solutions containing such. The hydrogenation catalyst
is preferably selected from the group of metals, salts and complexes
thereof of the group consisting of at least one of platinum, palladium,
rhodium, iridium, ruthenium and mixtures thereof or the group consisting
of at least one of nickel, molybdenum, cobalt, tungsten, titanium,
chromium and mixtures thereof. Reference to the catalytically active
metal or metals is intended to encompass such metal or metals in
the elemental state or in some form such as an oxide, sulfide, halide,
carboxylate and the like. The hydrogenation catalyst is present
in an effective amount to provide the hydrogenation function of
the hydrocracking catalyst, and preferably in the range of from
0.05 to 25% by weight.
Dewaxing
[0091] SSZ-71 preferably predominantly in the hydrogen form, can
be used to dewax hydrocarbonaceous feeds by selectively removing
straight chain paraffins. Typically, the viscosity index of the
dewaxed product is improved (compared to the waxy feed) when the
waxy feed is contacted with SSZ-71 under isomerization dewaxing
conditions.
[0092] The catalytic dewaxing conditions are dependent in large
measure on the feed used and upon the desired pour point. Hydrogen
is preferably present in the reaction zone during the catalytic
dewaxing process. The hydrogen to feed ratio is typically between
about 500 and about 30000 SCF/bbl (standard cubic feet per barrel)
(0.089 to 5.34 SCM/liter (standard cubic meters/liter)), preferably
about 1000 to about 20000 SCF/bbl (0.178 to 3.56 SCM/liter). Generally,
hydrogen will be separated from the product and recycled to the
reaction zone. Typical feedstocks include light gas oil, heavy gas
oils and reduced crudes boiling above about 350.degree. F. (177.degree.
C.).
[0093] A typical dewaxing process is the catalytic dewaxing of
a hydrocarbon oil feedstock boiling above about 350.degree. F. (177.degree.
C.) and containing straight chain and slightly branched chain hydrocarbons
by contacting the hydrocarbon oil feedstock in the presence of added
hydrogen gas at a hydrogen pressure of about 15-3000 psi (0.103-20.7
Mpa) with a catalyst comprising SSZ-71 and at least one Group VIII
metal.
[0094] The SSZ-71 hydrodewaxing catalyst may optionally contain
a hydrogenation component of the type commonly employed in dewaxing
catalysts. See the aforementioned U.S. Pat. No. 4910006 and U.S.
Pat. No. 5316753 for examples of these hydrogenation components.
[0095] The hydrogenation component is present in an effective amount
to provide an effective hydrodewaxing and hydroisomerization catalyst
preferably in the range of from about 0.05 to 5% by weight. The
catalyst may be run in such a mode to increase isomerization dewaxing
at the expense of cracking reactions.
[0096] The feed may be hydrocracked, followed by dewaxing. This
type of two stage process and typical hydrocracking conditions are
described in U.S. Pat. No. 4921594 issued May 1 1990 to Miller,
which is incorporated herein by reference in its entirety.
[0097] SSZ-71 may also be utilized as a dewaxing catalyst in the
form of a layered catalyst. That is, the catalyst comprises a first
layer comprising molecular sieve SSZ-71 and at least one Group VIII
metal, and a second layer comprising an aluminosilicate zeolite
which is more shape selective than molecular sieve SSZ-71. The use
of layered catalysts is disclosed in U.S. Pat. No. 5149421 issued
Sep. 22 1992 to Miller, which is incorporated by reference herein
in its entirety. The layering may also include a bed of SSZ-71 layered
with a non-zeolitic component designed for either hydrocracking
or hydrofinishing.
[0098] SSZ-71 may also be used to dewax raffinates, including bright
stock, under conditions such as those disclosed in U.S. Pat. No.
4181598 issued Jan. 1 1980 to Gillespie et al., which is incorporated
by reference herein in its entirety.
[0099] It is often desirable to use mild hydrogenation (sometimes
referred to as hydrofinishing) to produce more stable dewaxed products.
The hydrofinishing step can be performed either before or after
the dewaxing step, and preferably after. Hydrofinishing is typically
conducted at temperatures ranging from about 190.degree. C. to about
340.degree. C. at pressures from about 400 psig to about 3000 psig
(2.76 to 20.7 Mpa gauge) at space velocities (LHSV) between about
0.1 and 20 and a hydrogen recycle rate of about 400 to 1500 SCF/bbl
(0.071 to 0.27 SCM/liter). The hydrogenation catalyst employed must
be active enough not only to hydrogenate the olefins, diolefins
and color bodies which may be present, but also to reduce the aromatic
content. Suitable hydrogenation catalyst are disclosed in U.S. Pat.
No. 4921594 issued May 1 1990 to Miller, which is incorporated
by reference herein in its entirety. The hydrofinishing step is
beneficial in preparing an acceptably stable product (e.g., a lubricating
oil) since dewaxed products prepared from hydrocracked stocks tend
to be unstable to air and light and tend to form sludges spontaneously
and quickly. Lube oil may be prepared using SSZ-71. For example,
a C.sub.20+ lube oil may be made by isomerizing a C.sub.20+ olefin
feed over a catalyst comprising SSZ-71 in the hydrogen form and
at least one Group VIII metal. Alternatively, the lubricating oil
may be made by hydrocracking in a hydrocracking zone a hydrocarbonaceous
feedstock to obtain an effluent comprising a hydrocracked oil, and
catalytically dewaxing the effluent at a temperature of at least
about 400.degree. F. (204.degree. C.) and at a pressure of from
about 15 psig to about 3000 psig (0.103-20.7 Mpa gauge) in the presence
of added hydrogen gas with a catalyst comprising SSZ-71 in the hydrogen
form and at least one Group VIII metal.
Aromatics Formation
[0100] SSZ-71 can be used to convert light straight run naphthas
and similar mixtures to highly aromatic mixtures. Thus, normal and
slightly branched chained hydrocarbons, preferably having a boiling
range above about 40.degree. C. and less than about 200.degree.
C., can be converted to products having a substantial higher octane
aromatics content by contacting the hydrocarbon feed with a catalyst
comprising SSZ-71. It is also possible to convert heavier feeds
into BTX or naphthalene derivatives of value using a catalyst comprising
SSZ-71.
[0101] The conversion catalyst preferably contains a Group VIII
metal compound to have sufficient activity for commercial use. By
Group VIII metal compound as used herein is meant the metal itself
or a compound thereof. The Group VIII noble metals and their compounds,
platinum, palladium, and iridium, or combinations thereof can be
used. Rhenium or tin or a mixture thereof may also be used in conjunction
with the Group VIII metal compound and preferably a noble metal
compound. The most preferred metal is platinum. The amount of Group
VIII metal present in the conversion catalyst should be within the
normal range of use in reforming catalysts, from about 0.05 to 2.0
weight percent, preferably 0.2 to 0.8 weight percent.
[0102] It is critical to the selective production of aromatics
in useful quantities that the conversion catalyst be substantially
free of acidity, for example, by neutralizing the molecular sieve
with a basic metal, e.g., alkali metal, compound. Methods for rendering
the catalyst free of acidity are known in the art. See the aforementioned
U.S. Pat. No. 4910006 and U.S. Pat. No. 5316753 for a description
of such methods.
[0103] The preferred alkali metals are sodium, potassium, rubidium
and cesium. The molecular sieve itself can be substantially free
of acidity only at very high silica:alumina mole ratios.
Catalytic Cracking
[0104] Hydrocarbon cracking stocks can be catalytically cracked
in the absence of hydrogen using SSZ-71 preferably predominantly
in the hydrogen form.
[0105] When SSZ-71 is used as a catalytic cracking catalyst in
the absence of hydrogen, the catalyst may be employed in conjunction
with traditional cracking catalysts, e.g., any aluminosilicate heretofore
employed as a component in cracking catalysts. Typically, these
are large pore, crystalline aluminosilicates. Examples of these
traditional cracking catalysts are disclosed in the aforementioned
U.S. Pat. No. 4910006 and U.S. Pat. No 5316753. When a traditional
cracking catalyst (TC) component is employed, the relative weight
ratio of the TC to the SSZ-71 is generally between about 1:10 and
about 500:1 desirably between about 1:10 and about 200:1 preferably
between about 1:2 and about 50:1 and most preferably is between
about 1:1 and about 20:1. The novel molecular sieve and/or the traditional
cracking component may be further ion exchanged with rare earth
ions to modify selectivity.
[0106] The cracking catalysts are typically employed with an inorganic
oxide matrix component. See the aforementioned U.S. Pat. No. 4910006
and U.S. Pat. No. 5316753 for examples of such matrix components.
Isomerization
[0107] The present catalyst is highly active and highly selective
for isomerizing C.sub.4 to C.sub.7 hydrocarbons. The activity means
that the catalyst can operate at relatively low temperature which
thermodynamically favors highly branched paraffins. Consequently,
the catalyst can produce a high octane product. The high selectivity
means that a relatively high liquid yield can be achieved when the
catalyst is run at a high octane.
[0108] The present process comprises contacting the isomerization
catalyst, i.e., a catalyst comprising SSZ-71 in the hydrogen form,
with a hydrocarbon feed under isomerization conditions. The feed
is preferably a light straight run fraction, boiling within the
range of 30.degree. F. to 250.degree. F. (-1.degree. C. to 121.degree.
C.) and preferably from 60.degree. F. to 200.degree. F. (16.degree.
C. to 93.degree. C.). Preferably, the hydrocarbon feed for the process
comprises a substantial amount of C.sub.4 to C.sub.7 normal and
slightly branched low octane hydrocarbons, more preferably C.sub.5
and C.sub.6 hydrocarbons.
[0109] It is preferable to carry out the isomerization reaction
in the presence of hydrogen. Preferably, hydrogen is added to give
a hydrogen to hydrocarbon ratio (H.sub.2/HC) of between 0.5 and
10 H.sub.2/HC, more preferably between 1 and 8 H.sub.2/HC. See the
aforementioned U.S. Pat. No. 4910006 and U.S. Pat. No. 5316753
for a further discussion of isomerization process conditions.
[0110] A low sulfur feed is especially preferred in the present
process. The feed preferably contains less than 10 ppm, more preferably
less than 1 ppm, and most preferably less than 0.1 ppm sulfur. In
the case of a feed which is not already low in sulfur, acceptable
levels can be reached by hydrogenating the feed in a presaturation
zone with a hydrogenating catalyst which is resistant to sulfur
poisoning. See the aforementioned U.S. Pat. No. 4910006 and U.S.
Pat. No. 5316753 for a further discussion of this hydrodesulfurization
process.
[0111] It is preferable to limit the nitrogen level and the water
content of the feed. Catalysts and processes which are suitable
for these purposes are known to those skilled in the art.
[0112] After a period of operation, the catalyst can become deactivated
by sulfur or coke. See the aforementioned U.S. Pat. No. 4910006
and U.S. Pat. No. 5316753 for a further discussion of methods
of removing this sulfur and coke, and of regenerating the catalyst.
[0113] The conversion catalyst preferably contains a Group VIII
metal compound to have sufficient activity for commercial use. By
Group VIII metal compound as used herein is meant the metal itself
or a compound thereof. The Group VIII noble metals and their compounds,
platinum, palladium, and iridium, or combinations thereof can be
used. Rhenium and tin may also be used in conjunction with the noble
metal. The most preferred metal is platinum. The amount of Group
VIII metal present in the conversion catalyst should be within the
normal range of use in isomerizing catalysts, from about 0.05 to
2.0 weight percent, preferably 0.2 to 0.8 weight percent.
Alkylation and Transalkylation
[0114] SSZ-71 can be used in a process for the alkylation or transalkylation
of an aromatic hydrocarbon. The process comprises contacting the
aromatic hydrocarbon with a C.sub.2 to C.sub.16 olefin alkylating
agent or a polyalkyl aromatic hydrocarbon transalkylating agent,
under at least partial liquid phase conditions, and in the presence
of a catalyst comprising SSZ-71.
[0115] SSZ-71 can also be used for removing benzene from gasoline
by alkylating the benzene as described above and removing the alkylated
product from the gasoline.
[0116] For high catalytic activity, the SSZ-71 molecular sieve
should be predominantly in its hydrogen ion form. It is preferred
that, after calcination, at least 80% of the cation sites are occupied
by hydrogen ions and/or rare earth ions.
[0117] Examples of suitable aromatic hydrocarbon feedstocks which
may be alkylated or transalkylated by the process of the invention
include aromatic compounds such as benzene, toluene and xylene.
The preferred aromatic hydrocarbon is benzene. There may be occasions
where naphthalene or naphthalene derivatives such as dimethylnaphthalene
may be desirable. Mixtures of aromatic hydrocarbons may also be
employed.
[0118] Suitable olefins for the alkylation of the aromatic hydrocarbon
are those containing 2 to 20 preferably 2 to 4 carbon atoms, such
as ethylene, propylene, butene-1 trans-butene-2 and cis-butene-2
or mixtures thereof. There may be instances where pentenes are desirable.
The preferred olefins are ethylene and propylene. Longer chain alpha
olefins may be used as well.
[0119] When transalkylation is desired, the transalkylating agent
is a polyalkyl aromatic hydrocarbon containing two or more alkyl
groups that each may have from 2 to about 4 carbon atoms. For example,
suitable polyalkyl aromatic hydrocarbons include di-, tri- and tetra-alkyl
aromatic hydrocarbons, such as diethylbenzene, triethylbenzene,
diethylmethylbenzene (diethyltoluene), di-isopropylbenzene, di-isopropyltoluene,
dibutylbenzene, and the like. Preferred polyalkyl aromatic hydrocarbons
are the dialkyl benzenes. A particularly preferred polyalkyl aromatic
hydrocarbon is di-isopropylbenzene.
[0120] When alkylation is the process conducted, reaction conditions
are as follows. The aromatic hydrocarbon feed should be present
in stoichiometric excess. It is preferred that molar ratio of aromatics
to olefins be greater than four-to-one to prevent rapid catalyst
fouling. The reaction temperature may range from 100.degree. F.
to 600.degree. F. (38.degree. C. to 315.degree. C.), preferably
250.degree. F. to 450.degree. F. (121.degree. C. to 232.degree.
C.). The reaction pressure should be sufficient to maintain at least
a partial liquid phase in order to retard catalyst fouling. This
is typically 50 psig to 1000 psig (0.345 to 6.89 Mpa gauge) depending
on the feedstock and reaction temperature. Contact time may range
from 10 seconds to 10 hours, but is usually from 5 minutes to an
hour. The weight hourly space velocity (WHSV), in terms of grams
(pounds) of aromatic hydrocarbon and olefin per gram (pound) of
catalyst per hour, is generally within the range of about 0.5 to
50.
[0121] When transalkylation is the process conducted, the molar
ratio of aromatic hydrocarbon will generally range from about 1:1
to 25:1 and preferably from about 2:1 to 20:1. The reaction temperature
may range from about 100.degree. F. to 600.degree. F. (38.degree.
C. to 315.degree. C.), but it is preferably about 250.degree. F.
to 450.degree. F. (121.degree. C. to 232.degree. C.). The reaction
pressure should be sufficient to maintain at least a partial liquid
phase, typically in the range of about 50 psig to 1000 psig (0.345
to 6.89 Mpa gauge), preferably 300 psig to 600 psig (2.07 to 4.14
Mpa gauge). The weight hourly space velocity will range from about
0.1 to 10. U.S. Pat. No. 5082990 issued on Jan. 21 1992 to Hsieh,
et al. describes such processes and is incorporated herein by reference.
Conversion of Paraffins to Aromatics
[0122] SSZ-71 can be used to convert light gas C.sub.2-C.sub.6
paraffins to higher molecular weight hydrocarbons including aromatic
compounds. Preferably, the molecular sieve will contain a catalyst
metal or metal oxide wherein said metal is selected from the group
consisting of Groups IB, IIB, VIII and IIIA of the Periodic Table.
Preferably, the metal is gallium, niobium, indium or zinc in the
range of from about 0.05 to 5% by weight.
Isomerization of Olefins
[0123] SSZ-71 can be used to isomerize olefins. The feed stream
is a hydrocarbon stream containing at least one C.sub.4-6 olefin,
preferably a C.sub.4-6 normal olefin, more preferably normal butene.
Normal butene as used in this specification means all forms of normal
butene, e.g., 1-butene, cis-2-butene, and trans-2-butene. Typically,
hydrocarbons other than normal butene or other C.sub.4-6 normal
olefins will be present in the feed stream. These other hydrocarbons
may include, e.g., alkanes, other olefins, aromatics, hydrogen,
and inert gases.
[0124] The feed stream typically may be the effluent from a fluid
catalytic cracking unit or a methyl-tert-butyl ether unit. A fluid
catalytic cracking unit effluent typically contains about 40-60
weight percent normal butenes. A methyl-tert-butyl ether unit effluent
typically contains 40-100 weight percent normal butene. The feed
stream preferably contains at least about 40 weight percent normal
butene, more preferably at least about 65 weight percent normal
butene. The terms iso-olefin and methyl branched iso-olefin may
be used interchangeably in this specification.
[0125] The process is carried out under isomerization conditions.
The hydrocarbon feed is contacted in a vapor phase with a catalyst
comprising the SSZ-71. The process may be carried out generally
at a temperature from about 625.degree. F. to about 950.degree.
F. (329-510.degree. C.), for butenes, preferably from about 700.degree.
F. to about 900.degree. F. (371-482.degree. C.), and about 350.degree.
F. to about 650.degree. F. (177-343.degree. C.) for pentenes and
hexenes. The pressure ranges from subatmospheric to about 200 psig
(1.38 Mpa gauge), preferably from about 15 psig to about 200 psig
(0.103 to 1.38 Mpa gauge), and more preferably from about 1 psig
to about 150 psig (0.00689 to 1.03 Mpa gauge).
[0126] The liquid hourly space velocity during contacting is generally
from about 0.1 to about 50 hr.sup.-1 based on the hydrocarbon feed,
preferably from about 0.1 to about 20 hr.sup.-1 more preferably
from about 0.2 to about 10 hr.sup.-1 most preferably from about
1 to about 5 hr.sup.-1. A hydrogen/hydrocarbon molar ratio is maintained
from about 0 to about 30 or higher. The hydrogen can be added directly
to the feed stream or directly to the isomerization zone. The reaction
is preferably substantially free of water, typically less than about
two weight percent based on the feed. The process can be carried
out in a packed bed reactor, a fixed bed, fluidized bed reactor,
or a moving bed reactor. The bed of the catalyst can move upward
or downward. The mole percent conversion of, e.g., normal butene
to iso-butene is at least 10 preferably at least 25 and more preferably
at least 35.
Xylene Isomerization
[0127] SSZ-71 may also be useful in a process for isomerizing one
or more xylene isomers in a C.sub.8 aromatic feed to obtain ortho-,
meta-, and para-xylene in a ratio approaching the equilibrium value.
In particular, xylene isomerization is used in conjunction with
a separate process to manufacture para-xylene. For example, a portion
of the para-xylene in a mixed C.sub.8 aromatics stream may be recovered
by crystallization and centrifugation. The mother liquor from the
crystallizer is then reacted under xylene isomerization conditions
to restore ortho-, meta- and para-xylenes to a near equilibrium
ratio. At the same time, part of the ethylbenzene in the mother
liquor is converted to xylenes or to products which are easily separated
by filtration. The isomerate is blended with fresh feed and the
combined stream is distilled to remove heavy and light by-products.
The resultant C.sub.8 aromatics stream is then sent to the crystallizer
to repeat the cycle.
[0128] Optionally, isomerization in the vapor phase is conducted
in the presence of 3.0 to 30.0 moles of hydrogen per mole of alkylbenzene
(e.g., ethylbenzene). If hydrogen is used, the catalyst should comprise
about 0.1 to 2.0 wt. % of a hydrogenation/dehydrogenation component
selected from Group VIII (of the Periodic Table) metal component,
especially platinum or nickel. By Group VIII metal component is
meant the metals and their compounds such as oxides and sulfides.
[0129] Optionally, the isomerization feed may contain 10 to 90
wt. of a diluent such as toluene, trimethylbenzene, naphthenes or
paraffins.
Oligomerization
[0130] It is expected that SSZ-71 can also be used to oligomerize
straight and branched chain olefins having from about 2 to 21 and
preferably 2-5 carbon atoms. The oligomers which are the products
of the process are medium to heavy olefins which are useful for
both fuels, i.e., gasoline or a gasoline blending stock and chemicals.
[0131] The oligomerization process comprises contacting the olefin
feedstock in the gaseous or liquid phase with a catalyst comprising
SSZ-71.
[0132] The molecular sieve can have the original cations associated
therewith replaced by a wide variety of other cations according
to techniques well known in the art. Typical cations would include
hydrogen, ammonium and metal cations including mixtures of the same.
Of the replacing metallic cations, particular preference is given
to cations of metals such as rare earth metals, manganese, calcium,
as well as metals of Group II of the Periodic Table, e.g., zinc,
and Group VIII of the Periodic Table, e.g., nickel. One of the prime
requisites is that the molecular sieve have a fairly low aromatization
activity, i.e., in which the amount of aromatics produced is not
more than about 20% by weight. This is accomplished by using a molecular
sieve with controlled acid activity [alpha value] of from about
0.1 to about 120 preferably from about 0.1 to about 100 as measured
by its ability to crack n-hexane.
[0133] Alpha values are defined by a standard test known in the
art, e.g., as shown in U.S. Pat. No. 3960978 issued on Jun. 1
1976 to Givens et al. which is incorporated totally herein by reference.
If required, such molecular sieves may be obtained by steaming,
by use in a conversion process or by any other method which may
occur to one skilled in this art.
Condensation of Alcohols
[0134] SSZ-71 can be used to condense lower aliphatic alcohols
having 1 to 10 carbon atoms to a gasoline boiling point hydrocarbon
product comprising mixed aliphatic and aromatic hydrocarbon. The
process disclosed in U.S. Pat. No. 3894107 issued Jul. 8 1975
to Butter et al., describes the process conditions used in this
process, which patent is incorporated totally herein by reference.
[0135] The catalyst may be in the hydrogen form or may be base
exchanged or impregnated to contain ammonium or a metal cation complement,
preferably in the range of from about 0.05 to 5% by weight. The
metal cations that may be present include any of the metals of the
Groups I through VIII of the Periodic Table. However, in the case
of Group IA metals, the cation content should in no case be so large
as to effectively inactivate the catalyst, nor should the exchange
be such as to eliminate all acidity. There may be other processes
involving treatment of oxygenated substrates where a basic catalyst
is desired.
Methane Upgrading
[0136] Higher molecular weight hydrocarbons can be formed from
lower molecular weight hydrocarbons by contacting the lower molecular
weight hydrocarbon with a catalyst comprising SSZ-71 and a metal
or metal compound capable of converting the lower molecular weight
hydrocarbon to a higher molecular weight hydrocarbon. Examples of
such reactions include the conversion of methane to C.sub.2+ hydrocarbons
such as ethylene or benzene or both. Examples of useful metals and
metal compounds include lanthanide and or actinide metals or metal
compounds.
[0137] These reactions, the metals or metal compounds employed
and the conditions under which they can be run are disclosed in
U.S. Pat. No. 4734537 issued Mar. 291988 to Devries et al.;
U.S. Pat. No. 4939311 issued Jul. 3 1990 to Washecheck et al.;
U.S. Pat. No. 4962261 issued Oct. 9 1990 to Abrevaya et al.;
U.S. Pat. No. 5095161 issued Mar. 10 1992 to Abrevaya et al.;
U.S. Pat. No. 5105044 issued Apr. 14 1992 to Han et al.; U.S.
Pat. No. 5105046 issued Apr. 14 1992 to Washecheck; U.S. Pat.
No. 5238898 issued Aug. 24 1993 to Han et al.; U.S. Pat. No.
5321185 issued Jun. 14 1994 to van der Vaart; and U.S. Pat.
No. 5336825 issued Aug. 9 1994 to Choudhary et al., each of
which is incorporated herein by reference in its entirety.
Polymerization of 1-Olefins
[0138] The molecular sieve of the present invention may be used
in a catalyst for the polymerization of 1-olefins, e.g., the polymerization
of ethylene. To form the olefin polymerization catalyst, the molecular
sieve as hereinbefore described is reacted with a particular type
of organometallic compound. Organometallic compounds useful in forming
the polymerization catalyst include trivalent and tetravalent organotitanium
and organochromium compounds having alkyl moieties and, optionally,
halo moieties. In the context of the present invention the term
"alkyl" includes both straight and branched chain alkyl,
cycloalkyl and alkaryl groups such as benzyl.
[0139] Examples of trivalent and tetravalent organochromium and
organotitanium compounds are disclosed in U.S. Pat. No. 4376722
issued Mar. 151983 to Chester et al., U.S. Pat. No. 4377497
issued Mar. 22 1983 to Chester et al., U.S. Pat. No. 4446243
issued May 1 1984 to Chester et al., and U.S. Pat. No. 4526942
issued Jul. 2 1985 to Chester et al. The disclosure of the aforementioned
patents are incorporated herein by reference in their entirety.
[0140] Examples of the organometallic compounds used to form the
polymerization catalyst include, but are not limited to, compounds
corresponding to the general formula: MY.sub.nX.sub.m-n wherein
M is a metal selected from titanium and chromium; Y is alkyl; X
is halogen (e.g., Cl or Br); n is 1-4; and m is greater than or
equal to n and is 3 or4.
[0141] Examples of organotitanium and organochromium compounds
encompassed by such a formula include compounds of the formula CrY.sub.4
CrY.sub.3 CrY.sub.3X, CrY.sub.2X, CrY.sub.2X.sub.2 CrYX.sub.2
CrYX.sub.3 TiY.sub.4 TiY.sub.3 TiY.sub.3X, TiY.sub.2X, TIY.sub.2X.sub.2
TiYX.sub.2 TiYX.sub.3 wherein X can be Cl or Br and Y can be methyl,
ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl,
pentyl, isopentyl, neopentyl, hexyl, isohexyl, neohexyl, 2-ethybutyl,
octyl, 2-ethylhexyl, 22-diethylbutyl, 2-isopropyl-3-methylbutyl,
etc., cyclohexylalkyls such as, for example, cyclohexylmethyl, 2-cyclohexylethyl,
3-cyclyhexylpropyl, 4-cyclohexylbutyl, and the corresponding alkyl-substituted
cyclohexyl radicals as, for example, (4-methylcyclohexyl)methyl,
neophyl, i.e., beta, beta-dimethyl-phenethyl, benzyl, ethylbenzyl,
and p-isopropylbenzyl. Preferred examples of Y include C.sub.1-5
alkyl, especially butyl.
[0142] The organotitanium and organochromium materials employed
in the catalyst can be prepared by techniques well known in the
art. See, for example the aforementioned Chester et al. patents.
[0143] The organotitanium or organochromium compounds can be with
the molecular sieve of the present invention, such as by reacting
the organometallic compound and the molecular sieve, in order to
form the olefin polymerization catalyst. Generally, such a reaction
takes place in the same reaction medium used to prepare the organometallic
compound under conditions which promote formation of such a reaction
product. The molecular sieve can simply be added to the reaction
mixture after formation of the organometallic compound has been
completed. Molecular sieve is added in an amount sufficient to provide
from about 0.1 to 10 parts by weight, preferably from about 0.5
to 5 parts by weight, of organometallic compound in the reaction
medium per 100 parts by weight of molecular sieve.
[0144] Temperature of the reaction medium during reaction of organometallic
compound with molecular sieve is also maintained at a level which
is low enough to ensure the stability of the organometallic reactant.
Thus, temperatures in the range of from about -150.degree. C. to
50.degree. C., preferably from about -80.degree. C. to 0.degree.
C. can be usefully employed. Reaction times of from about 0.01 to
10 hours, more preferably from about 0.1 to 1 hour, can be employed
in reacting the organotitanium or organochromium compound with the
molecular sieve.
[0145] Upon completion of the reaction, the catalyst material so
formed may be recovered and dried by evaporating the reaction medium
solvent under a nitrogen atmosphere. Alternatively, olefin polymerization
reactions can be conducted in this same solvent based reaction medium
used to form the catalyst.
[0146] The polymerization catalyst can be used to catalyze polymerization
of 1-olefins. The polymers produced using the catalysts of this
invention are normally solid polymers of at least one mono-i-olefin
containing from 2 to 8 carbon atoms per molecule. These polymers
are normally solid homopolymers of ethylene or copolymers of ethylene
with another mono-1-olefin containing 3 to 8 carbon atoms per molecule.
Exemplary copolymers include those of ethylene/propylene, ethylene/1-butene,
ethylene/1-hexane, and ethylene/1-octene and the like. The major
portion of such copolymers is derived from ethylene and generally
consists of about 80-99 preferably 95-99 mole percent of ethylene.
These polymers are well suited for extrusion, blow molding, injection
molding and the like.
[0147] The polymerization reaction can be conducted by contacting
monomer or monomers, e.g., ethylene, alone or with one or more other
olefins, and in the substantial absence of catalyst poisons such
as moisture and air, with a catalytic amount of the supported organometallic
catalyst at a temperature and at a pressure sufficient to initiate
the polymerization reaction. If desired, an inert organic solvent
may be used as a diluent and to facilitate materials handling if
the polymerization reaction is conducted with the reactants in the
liquid phase, e.g. in a particle form (slurry) or solution process.
The reaction may also be conducted with reactants in the vapor phase,
e.g., in a fluidized bed arrangement in the absence of a solvent
but, if desired, in the presence of an inert gas such as nitrogen.
[0148] The polymerization reaction is carried out at temperatures
of from about 30.degree. C. or less, up to about 200.degree. C.
or more, depending to a great extent on the operating pressure,
the pressure of the olefin monomers, and the particular catalyst
being used and its concentration. Naturally, the selected operating
temperature is also dependent upon the desired polymer melt index
since temperature is definitely a factor in adjusting the molecular
weight of the polymer. Preferably, the temperature used is from
about 30.degree. C. to about 100.degree. C. in a conventional slurry
or "particle forming" process or from 100.degree. C. to
150.degree. C. in a "solution forming" process. A temperature
of from about 70.degree. C to 110.degree. C. can be employed for
fluidized bed processes.
[0149] The pressure to be used in the polymerization reactions
can be any pressure sufficient to initiate the polymerization of
the monomer(s) to high molecular weight polymer. The pressure, therefore,
can range from subatmospheric pressures, using an inert gas as diluent,
to superatmospheric pressures of up to about 30000 psig or more.
The preferred pressure is from atmospheric (0 psig) up to about
1000 psig. As a general rule, a pressure of 20 to 800 psig is most
preferred.
[0150] The selection of an inert organic solvent medium to be employed
in the solution or slurry process embodiments of this invention
is not too critical, but the solvent should be inert to the supported
organometallic catalyst and olefin polymer produced, and be stable
at the reaction temperature used. It is not necessary, however,
that the inert organic solvent medium also serve as a solvent for
the polymer to be produced. Among the inert organic solvents applicable
for such purposes may be mentioned saturated aliphatic hydrocarbons
having from about 3 to 12 carbon atoms per molecule such as hexane,
heptane, pentane, isooctane, purified kerosene and the like, saturated
cycloaliphatic hydrocarbons having from about 5 to 12 carbon atoms
per molecule such as cyclohexane, cyclopentane, dimethylcyclopentane
and methylcyclohexane and the like and aromatic hydrocarbons having
from about 6 to 12 carbon atoms per molecule such as benzene, toluene,
xylene, and the like. Particularly preferred solvent media are cyclohexane,
pentane, hexane and heptane.
[0151] Hydrogen can be introduced into the polymerization reaction
zone in order to decrease the molecular weight of the polymers produced
(i.e., give a much higher Melt Index, MI). Partial pressure of hydrogen
when hydrogen is used can be within the range of 5 to 100 psig,
preferably 25 to 75 psig. The melt indices of the polymers produced
in accordance with the instant invention can range from about 0.1
to about 70 or even higher.
[0152] More detailed description of suitable polymerization conditions
including examples of particle form, solution and fluidized bed
polymerization arrangements are found in Karapinka; U.S. Pat. No.
3709853; Issued Jan. 9 1973 and Karol et al; U.S. Pat. No. 4086408;
Issued Apr. 25 1978. Both of these patents are incorporated herein
by reference.
Hydrotreating
[0153] SSZ-71 is useful in a hydrotreating catalyst. During hydrotreatment,
oxygen, sulfur and nitrogen present in the hydrocarbonaceous feed
is reduced to low levels. Aromatics and olefins, if present in the
feed, may also have their double bonds saturated. In some cases,
the hydrotreating catalyst and hydrotreating conditions are selected
to minimize cracking reactions, which can reduce the yield of the
most desulfided product (typically useful as a fuel).
[0154] Hydrotreating conditions typically include a reaction temperature
between 400-900.degree. F. (204-482.degree. C.), preferably 650-850.degree.
F. (343-454.degree. C.); a pressure between 500 and 5000 psig (3.5-34.6
Mpa), preferably 1000 to 3000 psig (7.0-20.8 MPa); a feed rate (LHSV)
of 0.5 hr.sup.-1 to 20 hr.sup.-1 (v/v); and overall hydrogen consumption
300 to 2000 scf per barrel of liquid hydrocarbon feed (53.4-356
m.sup.3 H.sub.2/m.sup.3 feed). The hydrotreating catalyst will typically
be a composite of a Group VI metal or compound thereof, and a Group
VIII metal or compound thereof supported on the molecular sieve
of this invention. Typically, such hydrotreating catalyst are presulfided.
[0155] Catalysts useful for hydrotreating hydrocarbon feeds are
disclosed in U.S. Pat. No. 4347121 issued Aug. 31 1982 to Mayer
et al, and U.S. Pat. No. 4810357 issued Mar. 7 1989 to Chester
et al, both of which are incorporated herein by reference in their
entirety. Suitable catalysts include noble metals from Group VIII,
such as Fe, Co, Ni, Pt or Pd, and/or Group VI metals, such as Cr,
Mo, Sn or W. Examples of combinations of Group VIII and Group VI
metals include Ni--Mo or Ni--Sn. Other suitable catalysts are described
in U.S. Pat. No.4157294 issued Jun. 5 1979 to Iwao et al, and
U.S. Pat. No. 3904513 issued Sep. 9 1975 to Fischer et al. U.S.
Pat. No. 3852207 issued Dec. 31974 to Strangeland et al, describes
suitable noble metal catalysts and mild hydrotreating conditions.
The contents of these patents are hereby incorporated by reference.
[0156] The amount of hydrogenation component(s) in the catalyst
suitably range from about 0.5% to about 10% by weight of Group VIII
component(s) and from 5% to about 25% by weight of Group VI metal
component(s), calculated as metal oxide(s) per 100 parts by weight
of total catalyst., where the percentages by weight are based on
the weight of the catalyst before sulfiding. The hydrogenation component(s)
in the catalyst may be in the oxidic and/or sulfidic form.
Hydrogenation
[0157] SSZ-71 can be used in a catalyst to catalyze hydrogenation
of a hydrocarbon feed containing unsaturated hydrocarbons. The unsaturated
hydrocarbons can comprise olefins, dienes, polyenes, aromatic compounds
and the like.
[0158] Hydrogenation is accomplished by contacting the hydrocarbon
feed containing unsaturated hydrocarbons with hydrogen in the presence
of a catalyst comprising SSZ-71. The catalyst can also contain one
or more metals of Group VIB and Group VIII, including salts, complexes
and solutions thereof. Reference to these catalytically active metals
is intended to encompass such metals or metals in the elemental
state or in some form such as an oxide, sulfide, halide, carboxylate
and the like. Examples of such metals include metals, salts or complexes
wherein the metal is selected from the group consisting of platinum,
palladium, rhodium, iridium or combinations thereof, or the group
consisting of nickel, molybdenum, cobalt, tungsten, titanium, chromium,
vanadium, rhenium, manganese and combinations thereof.
[0159] The hydrogenation component of the catalyst (i.e., the aforementioned
metal) is present in an amount effective to provide the hydrogenation
function of the catalyst, preferably in the range of from 0.05 to
25% by weight.
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