U.S. patent application number 14/134600 was filed with the patent office on 2015-06-25 for phosphorus-modified fcc catalysts.
This patent application is currently assigned to BASF Corporation. The applicant listed for this patent is BASF Corporation. Invention is credited to Robert McGuire, JR., Gary M. Smith, Bilge Yilmaz.
Application Number | 20150174559 14/134600 |
Document ID | / |
Family ID | 53399007 |
Filed Date | 2015-06-25 |
United States Patent
Application |
20150174559 |
Kind Code |
A1 |
Smith; Gary M. ; et
al. |
June 25, 2015 |
Phosphorus-Modified FCC Catalysts
Abstract
Described are fluid catalytic cracking (FCC) compositions,
methods of manufacture and use. FCC catalyst compositions comprise
catalytic microspheres containing a zeolite, a non-zeolitic
component, and a rare earth component. The microspheres are
modified with phosphorus. The FCC catalyst composition can be used
to crack hydrocarbon feeds, particularly resid feeds containing
high V and Ni, resulting in lower hydrogen and coke yields.
Inventors: |
Smith; Gary M.; (Verona,
NJ) ; McGuire, JR.; Robert; (Nanuet, NY) ;
Yilmaz; Bilge; (New York, NY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
BASF Corporation |
Florham Park |
NJ |
US |
|
|
Assignee: |
BASF Corporation
Florham park
NJ
|
Family ID: |
53399007 |
Appl. No.: |
14/134600 |
Filed: |
December 19, 2013 |
Current U.S.
Class: |
208/114 ; 502/10;
502/65 |
Current CPC
Class: |
B01J 37/0045 20130101;
B01J 2229/20 20130101; B01J 2229/36 20130101; B01J 35/08 20130101;
B01J 2229/26 20130101; B01J 37/0201 20130101; C10G 11/18 20130101;
B01J 29/088 20130101; B01J 35/023 20130101; B01J 2229/186 20130101;
B01J 37/28 20130101; B01J 37/04 20130101; B01J 35/0006 20130101;
B01J 29/146 20130101; B01J 21/04 20130101; C10G 11/05 20130101;
B01J 23/8472 20130101; B01J 37/0009 20130101; B01J 21/16 20130101;
B01J 2229/126 20130101 |
International
Class: |
B01J 29/08 20060101
B01J029/08; C10G 11/02 20060101 C10G011/02 |
Claims
1. A fluid catalytic cracking (FCC) catalyst composition for
processing resid feeds comprising: catalytic microspheres
containing a non-zeolitic component, 5 to 25% by weight of a
transition alumina, 20% to 65% by weight of a zeolite component
intergrown with the non-zeolitic component, a rare earth component
and 1% to 5% by weight of a phosphorus component on an oxide basis,
wherein the catalytic microspheres are obtained by forming rare
earth-containing microspheres containing the non-zeolitic
component, the transition alumina, the zeolite component intergrown
within the non-zeolitic component, and yttria or a rare earth
component, and further adding the phosphorus component to the rare
earth-containing microspheres to provide the catalytic
microspheres, and wherein the FCC catalyst composition is effective
in preventing at least one of nickel and vanadium from increasing
coke and hydrogen yields during cracking of a hydrocarbon.
2. The FCC catalyst composition of claim 1, wherein the
non-zeolitic component is selected from the group consisting of
kaolinite, halloysite, montmorillonite, bentonite, attapulgite,
kaolin, amorphous kaolin, metakaolin, mullite, spinel, hydrous
kaolin, clay, gibbsite (alumina trihydrate), boehmite, titania,
alumina, silica, silica-alumina, silica-magnesia, magnesia and
sepiolite.
3. The FCC catalyst composition of claim 2, wherein the phosphorus
component is in the range of 2 wt. % to about 4.0 wt. %
P.sub.2O.sub.5 on an oxide basis.
4. The FCC catalyst composition of claim 3, wherein the rare-earth
component is selected from one or more of ceria, lanthana,
praseodymia, and neodymia.
5. The FCC catalyst composition of claim 4, wherein the rare earth
component is lanthana, and the lanthana is present in a range of 1
wt. % to about 5.0 wt. % on an oxide basis.
6. The FCC catalyst composition of claim 5, wherein the phosphorus
component is present in a range of 2 wt. % and about 3.5 wt. %
P.sub.2O.sub.5 on an oxide basis.
7. The FCC catalyst composition of claim 6, wherein the microsphere
has a phosphorus level of about 2.5-3.5 wt. % P.sub.2O.sub.5 on an
oxide basis and the rare earth metal component is present in an
amount of about 2-3 wt. % on an oxide basis.
8. A method of cracking a hydrocarbon feed under fluid catalytic
cracking conditions, the method comprising contacting the
hydrocarbon feed with the catalyst of claim 1.
9. The method of claim 8, wherein the non-zeolitic matrix component
is selected from the group consisting of kaolinite, halloysite,
montmorillonite, bentonite, attapulgite, kaolin, amorphous kaolin,
metakaolin, mullite, spinel, hydrous kaolin, clay, gibbsite
(alumina trihydrate), boehmite, titania, alumina, silica,
silica-alumina, silica-magnesia, magnesia and sepiolite.
10. The method of claim 9, wherein the phosphorus component is in
the range of 1 wt. % to about 5.0 wt. % P.sub.2O.sub.5 on an oxide
basis.
11. The method of claim 10, wherein the rare-earth component is
selected from one or more of ceria, lanthana, praseodymia, and
neodymia.
12. The method of claim 11, wherein the rare earth component is
lanthana, and the lanthana is present in a range of 1 wt. % to
about 5.0 wt. % on an oxide basis.
13. The method of claim 12, wherein the microsphere has a
phosphorus level of about 2.5 to 3.5 wt. % P.sub.2O.sub.5 on an
oxide basis, and the rare-earth metal component is present in an
amount of about 2-3 wt. %, based on the weight of the catalyst.
14. A method of manufacturing an FCC catalyst comprising:
pre-forming a precursor microsphere comprising a non-zeolitic
material and alumina; in situ crystallizing a zeolite on the
pre-formed microsphere to provide a zeolite-containing microsphere;
adding a rare earth component to the zeolite-containing microsphere
to provide a rare-earth-containing microsphere; and adding a
phosphorus component to the rare earth-containing precursor
microsphere to provide a catalytic microsphere.
15. The method of claim 14, wherein the phosphorus component is
added by contact with diammonium phosphate.
16. The method of claim 15, wherein the rare earth component
comprises lanthana, wherein the lanthana is added by ion
exchange.
17. The method of claim 16, further comprising adding a phosphorus
component to the zeolite-containing microsphere.
18. The method of claim 16, wherein the rare earth component and
the phosphorus component are added sequentially in separate
steps.
19. The method of claim 28, wherein the method comprises adding a
portion of the phosphorus component, then ion exchanging the rare
earth component and then adding an additional phosphorus component.
Description
TECHNICAL FIELD
[0001] The present invention relates to a fluid catalytic cracking
catalyst and to a hydrocarbon catalytic cracking process using the
catalyst. More particularly, the invention relates to a
phosphorus-containing catalyst for processing metal contaminated
resid feeds.
BACKGROUND
[0002] Catalytic cracking is a petroleum refining process that is
applied commercially on a very large scale. Catalytic cracking, and
particularly fluid catalytic cracking (FCC), is routinely used to
convert heavy hydrocarbon feedstocks to lighter products, such as
gasoline and distillate range fractions. In FCC processes, a
hydrocarbon feedstock is injected into the riser section of a FCC
unit, where the feedstock is cracked into lighter, more valuable
products upon contacting hot catalyst circulated to the
riser-reactor from a catalyst regenerator.
[0003] It has been recognized that for a fluid catalytic cracking
catalyst to be commercially successful, it must have commercially
acceptable activity, selectivity, and stability characteristics. It
must be sufficiently active to give economically attractive yields,
have good selectivity towards producing products that are desired
and not producing products that are undesired, and it must be
sufficiently hydrothermally stable and attrition resistant to have
a commercially useful life.
[0004] Excessive coke and hydrogen are undesirable in commercial
catalytic cracking processes. Even small increases in the yields of
these products relative to the yield of gasoline can cause
significant practical problems. For example, increases in the
amount of coke produced can cause undesirable increases in the heat
that is generated by burning off the coke during the highly
exothermic regeneration of the catalyst. Conversely, insufficient
coke production can also distort the heat balance of the cracking
process. In addition, in commercial refineries, expensive
compressors are used to handle high volume gases, such as hydrogen.
Increases in the volume of hydrogen produced, therefore, can add
substantially to the capital expense of the refinery.
[0005] Improvements in cracking activity and gasoline selectivity
of cracking catalysts do not necessarily go hand in hand. Thus, a
cracking catalyst can have outstandingly high cracking activity,
but if the activity results in a high level of conversion to coke
and/or gas at the expense of gasoline the catalyst will have
limited utility. Catalytic cracking in current FCC catalyst is
attributable to both the zeolite and non-zeolite (e.g. matrix)
components. Zeolite cracking tends to be gasoline selective, while
matrix cracking tends to be less gasoline selective.
[0006] In recent years, the oil refining industry has shifted to
processing a larger quantity of residual (resid) and
resid-containing feeds due to changes in the price structure and
availability of crude oil. Many refiners have been processing at
least a portion of residual oil in their units and several now run
a full residual oil cracking program. Processing resid feeds can
drastically alter yields of valuable products in a negative
direction relative to a light feed. Aside from operational
optimizations, the catalyst has a large impact on product
distribution. Several factors are important to resid catalyst
design. It is highly favorable if the catalyst can minimize coke
and hydrogen formation, maximize catalyst stability, and minimize
deleterious contaminant selectivity due to metal contaminants in
resid feedstocks.
[0007] Resid feeds typically contain contaminant metals including
Ni, V, Fe, Na, Ca, and others. Resid FCC for converting heavy resid
feeds with high Ni and V contaminants constitutes the fastest
growing FCC segment globally. Both Ni and V catalyze unwanted
dehydrogenation reactions, but Ni is an especially active
dehydrogenation catalyst. Ni significantly increases H.sub.2 and
coke yields. In addition to taking part in unwanted dehydrogenation
reactions, V comes with other major concerns as it is highly mobile
under FCC conditions and its interaction with the zeolite destroys
its framework structure, which manifests itself as increased
H.sub.2 and coke yields, as well as lower zeolite surface area
retention. Even small amounts (e.g., 1-5 ppm) of contaminant metals
in the feed deposit cumulatively on the catalyst and can result in
high H.sub.2 and coke yields during FCC operation, which is a major
concern for the refining industry.
[0008] Since the 1960s, most commercial fluid catalytic cracking
catalysts have contained zeolites as an active component. Such
catalysts have taken the form of small particles, called
microspheres, containing both an active zeolite component and a
non-zeolite component in the form of a high alumina, silica-alumina
(aluminosilicate) matrix. The active zeolitic component is
incorporated into the microspheres of the catalyst by one of two
general techniques. In one technique, the zeolitic component is
crystallized and then incorporated into microspheres in a separate
step. In the second technique, the in situ technique, microspheres
are first formed and the zeolitic component is then crystallized in
the microspheres themselves to provide microspheres containing both
zeolitic and non-zeolitic components. For many years a significant
proportion of commercial FCC catalysts used throughout the world
have been made by in situ synthesis from precursor microspheres
containing kaolin that had been calcined at different severities
prior to formation into microspheres by spray drying. U.S. Pat. No.
4,493,902 ("the '902 patent"), incorporated herein by reference in
its entirety, discloses the manufacture of fluid cracking catalysts
comprising attrition-resistant microspheres containing high Y
zeolite, formed by crystallizing sodium Y zeolite in porous
microspheres composed of metakaolin and spinel. The microspheres in
the '902 patent contain more than about 40%, for example 50-70% by
weight Y zeolite. Such catalysts can be made by crystallizing more
than about 40% sodium Y zeolite in porous microspheres composed of
a mixture of two different forms of chemically reactive calcined
clay, namely, metakaolin (kaolin calcined to undergo a strong
endothermic reaction associated with dehydroxylation) and kaolin
clay calcined under conditions more severe than those used to
convert kaolin to metakaolin, i.e., kaolin clay calcined to undergo
the characteristic kaolin exothermic reaction, sometimes referred
to as the spinel form of calcined kaolin. This characteristic
kaolin exothermic reaction is sometimes referred to as kaolin
calcined through its "characteristic exotherm." The microspheres
containing the two forms of calcined kaolin clay are immersed in an
alkaline sodium silicate solution, which is heated, until the
maximum obtainable amount of Y zeolite with faujasite structure is
crystallized in the microspheres.
[0009] Fluid cracking catalysts which contain silica-alumina or
alumina matrices are termed catalysts with "active matrix."
Catalysts of this type can be compared with those containing
untreated clay or a large quantity of silica, which are termed
"inactive matrix" catalysts. In relation to catalytic cracking,
despite the apparent disadvantage in selectivity, the inclusion of
aluminas or silica-alumina has been beneficial in certain
circumstances. For instance when processing a
hydrotreated/demetallated vacuum gas oil (hydrotreated VGO) the
penalty in non-selective cracking is offset by the benefit of
cracking or "upgrading" the larger feed molecules which are
initially too large to fit within the rigorous confines of the
zeolite pores. Once "precracked" on the alumina or silica-alumina
surface, the smaller molecules may then be selectively cracked
further to gasoline material over the zeolite portion of the
catalyst. While one would expect that this precracking scenario
might be advantageous for resid feeds, they are, unfortunately,
characterized as being heavily contaminated with metals such as
nickel and vanadium and, to a lesser extent, iron. When a metal
such as nickel deposits on a high surface area alumina such as
those found in typical FCC catalysts, it is dispersed and
participates as highly active centers for the catalytic reactions
which result in the formation of contaminant coke (contaminant coke
refers to the coke produced discretely from reactions catalyzed by
contaminant metals). This additional coke exceeds that which is
acceptable by refiners. Loss of activity or selectivity of the
catalyst may also occur if the metal contaminants (e.g. Ni, V) from
the hydrocarbon feedstock deposit onto the catalyst. These metal
contaminants are not removed by standard regeneration (burning) and
contribute to high levels of hydrogen, dry gas and coke and reduce
significantly the amount of gasoline that can be made.
[0010] It would be desirable to provide FCC catalyst compositions,
methods of manufacture, and FCC processes that reduce coke and
hydrogen yields, in particular, in feeds containing high levels of
transition metals, for example, in a resid feed.
SUMMARY
[0011] One aspect of the invention is directed to a fluid catalytic
cracking (FCC) catalyst composition for processing resid feeds.
Various embodiments are listed below. It will be understood that
the embodiments listed below may be combined not only as listed
below, but in other suitable combinations in accordance with the
scope of the invention.
[0012] In embodiment one, the catalyst composition comprises:
catalytic microspheres containing a non-zeolitic component, 5 to
25% by weight of a transition alumina, 20% to 65% by weight of a
zeolite component intergrown with the non-zeolitic component, a
rare earth component and 1% to 5% by weight of a phosphorus
component on an oxide basis, wherein the catalytic microspheres are
obtained by forming rare earth-containing microspheres containing
the non-zeolitic component, the transition alumina, the zeolite
component intergrown within the non-zeolitic component, and yttria
or a rare earth component, and further adding the phosphorus
component to the rare earth-containing microspheres to provide the
catalytic microspheres, and wherein the FCC catalyst composition is
effective in preventing at least one of nickel and vanadium from
increasing coke and hydrogen yields during cracking of a
hydrocarbon.
[0013] Embodiment two is directed to a modification of catalyst
composition embodiment one, wherein the non-zeolitic component is
selected from the group consisting of kaolinite, halloysite,
montmorillonite, bentonite, attapulgite, kaolin, amorphous kaolin,
metakaolin, mullite, spinel, hydrous kaolin, clay, gibbsite
(alumina trihydrate), boehmite, titania, alumina, silica,
silica-alumina, silica-magnesia, magnesia and sepiolite.
[0014] Embodiment three is directed to a modification of catalyst
composition embodiment one or two, wherein the phosphorus component
is in the range of 2 wt. % to about 4.0 wt. % P.sub.2O.sub.5 on an
oxide basis.
[0015] Embodiment four is directed to a modification of any of
catalyst composition embodiments one through three, wherein the
rare-earth component is selected from one or more of ceria,
lanthana, praseodymia, and neodymia.
[0016] Embodiment five is directed to a modification of any of
catalyst composition embodiments one through four, wherein the rare
earth component is lanthana, and the lanthana is present in a range
of 1 wt. % to about 5.0 wt. % on an oxide basis.
[0017] Embodiment six is directed to a modification of any of
catalyst composition embodiments one through five, wherein the
phosphorus component is present in a range of 2 wt. % and about 3.5
wt. % P.sub.2O.sub.5 on an oxide basis.
[0018] Embodiment seven is directed to a modification of any of
catalyst composition embodiments one through six, wherein the
microsphere has a phosphorus level of about 2.5-3.5 wt. %
P.sub.2O.sub.5 on an oxide basis and the rare earth metal component
is present in an amount of about 2-3 wt. % on an oxide basis.
[0019] Another aspect of the invention is directed to a method of
cracking a hydrocarbon feed under fluid catalytic cracking
conditions. Therefore, an eighth embodiment of the invention is
directed to a method comprising contacting the hydrocarbon feed
with the catalyst composition of any of embodiments one through
seven.
[0020] Embodiment nine is directed to a modification of method
embodiment eight, wherein the non-zeolitic matrix component is
selected from the group consisting of kaolinite, halloysite,
montmorillonite, bentonite, attapulgite, kaolin, amorphous kaolin,
metakaolin, mullite, spinel, hydrous kaolin, clay, gibbsite
(alumina trihydrate), boehmite, titania, alumina, silica,
silica-alumina, silica-magnesia, magnesia and sepiolite.
[0021] Embodiment ten is directed to a modification of method
embodiment eight or nine, wherein the phosphorus component is in
the range of 1 wt. % to about 5.0 wt. % P.sub.2O.sub.5 on an oxide
basis.
[0022] Embodiment eleven is directed to a modification of any of
method embodiments eight through ten, wherein the rare-earth
component is selected from one or more of ceria, lanthana,
praseodymia, and neodymia.
[0023] Embodiment twelve is directed to a modification of any of
method embodiments eight through eleven, wherein the rare earth
component is lanthana, and the lanthana is present in a range of 1
wt. % to about 5.0 wt. % on an oxide basis.
[0024] Embodiment thirteen is directed to a modification of any of
method embodiments eight through twelve, wherein the microsphere
has a phosphorus level of about 2.5 to 3.5 wt. % P.sub.2O.sub.5 on
an oxide basis, and the rare-earth metal component is present in an
amount of about 2-3 wt. %, based on the weight of the catalyst.
[0025] Another aspect of the invention is directed to a method of
manufacturing an FCC catalyst. Therefore, a fourteenth embodiment
of the invention is directed to a method comprising pre-forming a
precursor microsphere comprising a non-zeolitic material and
alumina; in situ crystallizing a zeolite on the pre-formed
microsphere to provide a zeolite-containing microsphere; adding a
rare earth component to the zeolite-containing microsphere to
provide a rare-earth-containing microsphere; and adding a
phosphorus component to the rare earth-containing precursor
microsphere to provide a catalytic microsphere.
[0026] Embodiment fifteen is directed to a modification of method
embodiment fourteen, wherein the phosphorus component is added by
contact with diammonium phosphate.
[0027] Embodiment sixteen is directed to a modification of method
embodiment fourteen or fifteen, wherein the rare earth component
comprises lanthana, wherein the lanthana is added by ion
exchange.
[0028] Embodiment seventeen is directed to a modification of any of
method embodiments fourteen through sixteen, further comprising
adding a phosphorus component to the zeolite-containing
microsphere.
[0029] Embodiment eighteen is directed to a modification of any of
method embodiments fourteen through seventeen, wherein the rare
earth component and the phosphorus component are added sequentially
in separate steps.
[0030] Embodiment nineteen is directed to a modification of any of
method embodiments fourteen through eighteen, wherein the method
comprises adding a portion of the phosphorus component, then ion
exchanging the rare earth component and then adding an additional
phosphorus component.
BRIEF DESCRIPTION OF DRAWINGS
[0031] FIG. 1 is a graph comparing the hydrogen yields of cracking
catalysts according to one or more embodiments and comparative
catalysts upon cracking a heavy aromatic feed;
[0032] FIG. 2 is a graph comparing the contaminant coke yields of
cracking catalysts according to one or more embodiments and
comparative catalysts upon cracking a heavy aromatic feed;
[0033] FIG. 3 is a graph comparing the hydrogen yields of cracking
catalysts according one or more embodiments and comparative
catalysts upon cracking a light feed; and
[0034] FIG. 4 is a graph comparing the contaminant coke yields of
cracking catalysts according to one or more embodiments and
comparative catalysts upon cracking a light aromatic feed.
DETAILED DESCRIPTION
[0035] Before describing several exemplary embodiments of the
invention, it is to be understood that the invention is not limited
to the details of construction or process steps set forth in the
following description. The invention is capable of other
embodiments and of being practiced or being carried out in various
ways.
[0036] Embodiments of the present invention provide a FCC catalyst
using phosphorus-modified microspheres, which, according to one or
more embodiments, can be made by spray drying a mixture of mullite,
hydrous kaolin, boehmite, and a silicate binder, followed by the in
situ crystallization of zeolite Y, and then ion exchange,
phosphorus loading and calcination. Phosphorus modification of FCC
catalyst microspheres not only results in lower hydrogen and coke
yields but also results in higher zeolite surface area retention
rates when processing hydrocarbon feeds, particularly resid feeds
contaminated with transition metals, namely Ni and V.
[0037] According to one or more embodiments, a catalyst composition
is provided which exhibits higher performance due to the
interaction of the phosphate species with contaminant metals. The
phosphate species prevents contaminant metals from interfering with
catalyst selectivity, reducing coke and hydrogen yields, and
enhancing zeolite stability.
[0038] With respect to the terms used in this disclosure, the
following definitions are provided.
[0039] As used herein, the term "catalyst" or "catalyst
composition" or "catalyst material" refers to a material that
promotes a reaction.
[0040] As used herein, the term "fluid catalytic cracking" or "FCC"
refers to a conversion process in petroleum refineries wherein
high-boiling, high-molecular weight hydrocarbon fractions of
petroleum crude oils are converted to more valuable gasoline,
olefinic gases, and other products.
[0041] "Cracking conditions" or "FCC conditions" refers to typical
FCC process conditions. Typical FCC processes are conducted at
reaction temperatures of 450.degree. to 650.degree. C. with
catalyst regeneration temperatures of 600.degree. to 850.degree. C.
Hot regenerated catalyst is added to a hydrocarbon feed at the base
of a rise reactor. The fluidization of the solid catalyst particles
may be promoted with a lift gas. The catalyst vaporizes and
superheats the feed to the desired cracking temperature. During the
upward passage of the catalyst and feed, the feed is cracked, and
coke deposits on the catalyst. The coked catalyst and the cracked
products exit the riser and enter a solid-gas separation system,
e.g., a series of cyclones, at the top of the reactor vessel. The
cracked products are fractionated into a series of products,
including gas, gasoline, light gas oil, and heavy cycle gas oil.
Some heavier hydrocarbons may be recycled to the reactor.
[0042] As used herein, the term "feed" or "feedstock" refers to
that portion of crude oil that has a high boiling point and a high
molecular weight. In FCC processes, a hydrocarbon feedstock is
injected into the riser section of a FCC unit, where the feedstock
is cracked into lighter, more valuable products upon contacting hot
catalyst circulated to the riser-reactor from a catalyst
regenerator.
[0043] As used herein, the term "resid" refers to that portion of
crude oil that has a high boiling point and a high molecular weight
and typically contains contaminant metals including Ni, V, Fe, Na,
Ca, and others. The contaminant metals, particularly Ni and V, have
detrimental effects on catalyst activity and performance. In some
embodiments, in a resid feed operation one of Ni and V metals
accumulate on the catalyst, and the FCC catalyst composition is
effective to contact nickel and vanadium during cracking.
[0044] As used herein, the term "non-zeolitic component" refers to
the components of a FCC catalyst that are not zeolites or molecular
sieves. As used herein, the non-zeolitic component can comprise
binder and filler. A non-zeolitic component may be referred to as
the matrix. According to one or more embodiments, the "non-zeolitic
component" can be selected from the group consisting of clay,
kaolinite, halloysite, montmorillonite, bentonite, attapulgite,
kaolin, amorphous kaolin, metakaolin, mullite, spinel, hydrous
kaolin, clay, gibbsite (alumina trihydrate), boehmite, titania,
alumina, silica, silica-alumina, silica-magnesia, magnesia and
sepiolite. The non-zeolitic component can be an
aluminosilicate.
[0045] As used herein, the term "zeolite" refers to is a
crystalline aluminosilicate with a framework based on an extensive
three-dimensional network of oxygen ions and have a substantially
uniform pore distribution.
[0046] As used herein, the term "intergrown zeolite" refers to a
zeolite that is formed by an in situ crystallization process.
[0047] As used herein, the term "in situ crystallized" refers to
the process in which a zeolite is grown or intergrown directly
on/in a microsphere and is intimately associated with the matrix or
non-zeolitic material, for example, as described in U.S. Pat. Nos.
4,493,902 and 6,656,347. The zeolite is intergrown within the
macropores of the microsphere, such that the zeolite is uniformly
dispersed on the matrix or non-zeolitic material.
[0048] As used herein, the terms "preformed microspheres" or
"precursor microspheres" refer to microspheres obtained by spray
drying and calcining a non-zeolitic matrix component and a
transition alumina.
[0049] As used herein, the term "zeolite-containing microsphere"
refers to a microsphere obtained by in situ crystallizing a zeolite
material on pre-formed precursor microspheres. The zeolite is
intergrown directly on/in the macropores of the precursor
microsphere such that the zeolite is intimately associated and
uniformly dispersed on the matrix or non-zeolitic material.
[0050] As used herein, the term "rare-earth-containing microsphere"
refers to microspheres that include an in situ crystallized zeolite
(i.e. zeolite-containing microsphere) and are treated with a rare
earth component such that the rare earth component is intimately
associated with the matrix or non-zeolitic material.
[0051] As used herein, the term "catalytic microsphere" refers to
microspheres that are obtained by addition of a phosphorus
component to a rare-earth-containing microsphere. Catalytic
microspheres contain a non-zeolitic component (or matrix material),
a transition alumina, an in situ crystallized zeolite, a rare-earth
component, and a phosphorus component.
[0052] "Transition alumina" is defined as any alumina which is
intermediate between the thermodynamically stable phases of
gibbsite, bayerite, boehmite, pseudoboehmite and nordstrandite on
one end of the spectrum and alpha alumina or corundum on the other.
Such transition aluminas may be viewed as metastable phases. A
scheme of the transformation sequence can be found in the text:
Oxides and Hydroxides of Aluminum by K. Wefers and C. Misra; Alcoa
Technical Paper No. 19, revised; copyright Aluminum Company of
America Laboratories, 1987.
[0053] FCC catalyst compositions which include a zeolite component
have a catalytically active crystallized aluminosilicate material,
such as, for example, a large-pore zeolite crystallized on or in a
microsphere comprising non-zeolitic material. Large pore zeolite
cracking catalysts have pore openings of greater than about 7
Angstroms in effective diameter. Conventional large-pore molecular
sieves include zeolite X; REX; zeolite Y; Ultrastable Y (USY); Rare
Earth exchanged Y (REY); Rare Earth exchanged USY (REUSY);
Dealuminated Y (DeAl Y); Ultrahydrophobic Y (UHPY); and/or
dealuminated silicon-enriched zeolites, e.g., LZ-210. According to
one or more embodiments, the FCC catalyst comprises catalytic
microspheres comprising a crystalline aluminosilicate material
selected from zeolite Y, ZSM-20, ZSM-5, zeolite beta, zeolite L;
and naturally occurring zeolites such as faujasite, mordenite and
the like, and a non-zeolitic component. These materials may be
subjected to conventional treatments, such calcinations and ion
exchange with rare earths to increase stability.
[0054] Microspheres comprising hydrous kaolin clay and/or
metakaolin, a dispersible boehmite, optionally spinel and/or
mullite, and a sodium silicate or silica sol binder can be prepared
in accordance with the techniques described in U.S. Pat. No.
6,716,338, which is incorporated herein by reference. For example,
the catalysts can be made by crystallizing the desired amount of
sodium Y zeolite in porous microspheres composed of a mixture of
two different forms of chemically reactive calcined clay, namely,
metakaolin and spinel. The microspheres containing the two forms of
calcined kaolin clay are immersed in an alkaline sodium silicate
solution, which is heated, until the maximum obtainable amount of Y
zeolite is crystallized in the microspheres. The amount of zeolite
according to embodiments of the invention is in the range of 20% to
95%, or 30% to 60%, or 30% to 45% by weight based on the weight of
the FCC catalyst composition.
[0055] Preparation of Phosphorus Containing Microspheres
[0056] A first aspect of the invention is directed to a fluid
catalytic cracking (FCC) catalyst composition for resid feed
refining. In one or more embodiments, the FCC catalyst composition
comprises catalytic microspheres containing a non-zeolitic
component, 5 to 25% by weight of a transition alumina, 20% to 95%
by weight of a zeolite component intergrown with the non-zeolitic
component, a rare earth component and 1% to 5% by weight of a
phosphorus component on an oxide basis. In one or more embodiments,
the catalytic microspheres are obtained by forming rare-earth
containing microspheres containing the non-zeolitic component, the
transition alumina, the zeolite component intergrown within the
non-zeolitic component, and the rare earth component, and further
adding the phosphorus component to the rare earth-containing
microspheres to provide the catalytic microspheres. In one or more
embodiments, the FCC catalyst composition is effective to prevent
at least one of nickel and vanadium from increasing coke and
hydrogen yields during cracking of a hydrocarbon.
[0057] An aqueous slurry of finely divided hydrous kaolin, kaolin
that has been calcined through its characteristic exotherm, and
binder is prepared. The slurry can optionally contain boehmite. In
specific embodiments, the hydrous kaolin, calcined kaolin and
binder are premixed in one tank and fed to the spray drier from one
line. When present, an aqueous alumina slurry, peptized such as
with formic acid is introduced from a separate line immediately
prior to when the whole mix enters the spray drier. Other mixing
and injection protocols may also be useful. For example, a polymer
dispersed alumina, for example dispersed with Flosperse.RTM. can be
used in the process. The final slurry solids are about 30-70 wt. %.
The aqueous slurry is then spray dried to obtain microspheres
comprising a silica bonded mixture of hydrated kaolin, boehmite and
kaolin that has been calcined at least substantially through its
characteristic exotherm (spinel, or mullite, or both spinel and
mullite). The preformed microspheres have average particle
diameters that are typical of commercial fluid catalytic cracking
catalysts, e.g., 65-85 microns. Suitable spray drying conditions
are set forth in the '902 patent.
[0058] The reactive kaolin of the slurry to form the preformed
microspheres can be formed of hydrated kaolin or calcined hydrous
kaolin (metakaolin) or mixtures thereof. The hydrous kaolin of the
feed slurry can suitably be either one or a mixture of ASP.RTM. 600
or ASP.RTM. 400 kaolin, derived from coarse white kaolin crudes.
Finer particle size hydrous kaolins can also be used, including
those derived from gray clay deposits, such as LHT pigment.
Purified water-processed kaolin clays from Middle Ga. can also be
used. Calcined products of these hydrous kaolins can be used as the
metakaolin component of the feed slurry.
[0059] A commercial source of powdered kaolin calcined through the
exotherm may be used as the spinel component. Hydrated kaolin clay
is converted to this state by calcining the kaolin at least
substantially completely through its characteristic exotherm. (The
exotherm is detectable by conventional differential thermal
analysis, DTA). After completion of calcination, the calcined clay
is pulverized into finely divided particles before being introduced
into the slurry that is fed to a spray dryer. The spray dried
product is repulverized. The surface area (BET) of typical spinel
form kaolin is low, e.g., 5-10 m.sup.2/g; however, when this
material is placed in a caustic environment such as that used for
crystallization, silica is leached, leaving an alumina-rich residue
having a high surface area, e.g. 100-200 m.sup.2/g (BET).
[0060] Mullite can also be used as a matrix component. Mullite is
made by firing clay at temperatures above 2000.degree. F. For
example M93 mullite may be made from the same kaolin clay source as
Ansilex 93, used for the preparation of spinel component. Mullite
can also be made from other kaolin clays. Mullite may also be made
from Kyanite clay. Heating Kyanite clay to a high temperature of
3000.degree. F., provides a more crystalline, purer mullite in the
calcined product than that obtained from kaolin clay.
[0061] According to one or more embodiments, the alumina used to
prepare the preformed microspheres is a highly dispersible
boehmite. Dispersibility of the hydrated alumina is the property of
the alumina to disperse effectively in an acidic media such as
formic acid of pH less than about 3.5. Such acid treatment is known
as peptizing the alumina. High dispersion is when 90% or more of
the alumina disperses into particles less than about 1 micron. When
this dispersed alumina solution is spray dried with the kaolin and
binder, the resulting preformed microsphere contains uniformly
distributed alumina throughout the microsphere.
[0062] After spray drying, the preformed microspheres are washed
and calcined at a temperature and for a time (e.g., for two to four
hours in a muffle furnace at a chamber temperature of about
1500.degree. to 1550.degree. F.) sufficient to convert the hydrated
clay component of the microspheres to metakaolin, leaving the
spinel component of the microspheres essentially unchanged. In
specific embodiments, the calcined preformed microspheres comprise
about 30 to 70% by weight metakaolin, about 10 to 50% by weight
spinel and/or mullite and 5 to about 25% by weight transition phase
alumina. In one or more embodiments, the transition phase alumina
comprises one or more of gamma, delta, theta, eta, or chi phase. In
specific embodiments, the surface area (BET, nitrogen) of the
crystalline boehmite (as well as the transition alumina) is below
150 m.sup.2/g, specifically below 125 m.sup.2/g, and more
specifically, below 100 m.sup.2/g, for example, 30-80
m.sup.2/g.
[0063] When boehmite is incorporated into FCC catalysts, it can
serve as a trap for transition metals, especially Ni. Without
intending to be bound by theory, it is thought that boehmite
inhibits the dehydrogenation activity of Ni in hydrocarbon feeds by
converting it to Ni-aluminate (NiAl.sub.2O.sub.4). In one or more
embodiments, the catalyst comprises from about 0.5% to 20% by
weight of boehmite. The transition alumina phase that results from
the dispersible boehmite during the preparative procedure and which
forms a portion of the matrix of the final catalyst, passivates the
Ni and V that are deposited onto the catalyst during the cracking
process, especially during cracking of heavy resid feeds.
[0064] The preformed or precursor microspheres are reacted with
zeolite seeds and an alkaline sodium silicate solution,
substantially as described in U.S. Pat. No. 5,395,809, the
teachings of which are incorporated herein by cross-reference. The
zeolite component is intergrown with the matrix component. The
microspheres are crystallized to a desired zeolite content (for
example, 20-65% by weight, or 30-60% by weight, or 30-45% by
weight), filtered, washed, ammonium exchanged, exchanged with
rare-earth cations if required, calcined, exchanged a second time
with ammonium ions, and calcined a second time if required, and
optionally ion-exchanged. The silicate for the binder can be
provided by sodium silicates with SiO.sub.2 to Na.sub.2O ratios of
from 1.5 to 3.5, more specifically, ratios of from 2.00 to
3.22.
[0065] In specific embodiments, the crystallized aluminosilicate
material comprises from about 20 to about 65 wt. % zeolite Y, for
example, 30% to 65% by weight, or 30% to 45% by weight, expressed
on the basis of the as-crystallized sodium faujasite form zeolite.
In one or more embodiments, the Y-zeolite component of the
crystalline aluminosilicate, in their sodium form, have a
crystalline unit cell size range of between 24.64-24.73 .ANG.,
corresponding to a SiO.sub.2/Al.sub.2O.sub.3 molar ratio of the
Y-zeolite of about 4.1-5.2.
[0066] After crystallization by reaction in a seeded sodium
silicate solution, the preformed microspheres contain crystalline
Y-zeolite in the sodium form. Sodium cations in the microspheres
are replaced with more desirable cations. This may be accomplished
by contacting the microspheres with solutions containing ammonium,
yttrium cations, rare earth cations or combinations thereof. In one
or more embodiments, the ion exchange step or steps are carried out
so that the resulting catalyst contains less than about 0.7%, more
specifically less than about 0.5% and even more specifically less
than about 0.2%, by weight Na.sub.2O. After ion exchange, the
microspheres are dried. Rare earth levels in the range of 0.1% to
12% by weight, specifically 1-5% by weight, and more specifically
2-3% by weight are contemplated. More specifically, examples of
rare earth compounds are the nitrates of lanthanum, cerium,
praseodymium, and neodymium. Typically, the amount of rare earth
added to the catalyst as a rare earth oxide will range from about 1
to 5%, typically 2-3 wt. % rare earth oxide (REO).
[0067] Following ammonium and rare earth exchange, the rare-earth
containing microsphere catalyst composition is further modified
with phosphorus to provide a catalytic microsphere. The microsphere
catalyst composition can be contacted with a medium containing an
anion, for example, a dihydrogen phosphate anion
(H.sub.2PO.sub.4.sup.-), a dihydrogen phosphite anion
(H.sub.2PO.sub.3.sup.-) or mixtures thereof for a time sufficient
to composite phosphorus, with the catalyst. Suitable amounts of
phosphorus to be incorporated in the catalyst include at least
about 0.5 weight percent, specifically at least about 0.7 weight
percent, more specifically from about 1 to 4 weight percent,
calculated as P.sub.2O.sub.5, based on the weight of the zeolite
plus whatever matrix remains associated with the zeolite.
[0068] The anion is derived from a phosphorus-containing component
selected from inorganic acids of phosphorus, salts of inorganic
acids of phosphorus, and mixtures thereof. Suitable
phosphorus-containing components include phosphorus acid
(H.sub.3PO.sub.3), phosphoric acid (H.sub.3PO.sub.4), salts of
phosphorus acid, salts of phosphoric acid and mixtures thereof.
Although any soluble salts of phosphorus acid and phosphoric acid,
such as alkali metal salts and ammonium salts may be used to
provide the dihydrogen phosphate or phosphite anion, in specific
embodiments, ammonium salts are used since the use of alkali metal
salts would require subsequent removal of the alkali metal from the
catalyst. In one embodiment, the anion is a dihydrogen phosphate
anion derived from monoammonium phosphate, diammonium phosphate and
mixtures thereof. Contact with the anion may be performed as at
least one step of contacting or a series of contacts which may be a
series of alternating and successive calcinations and dihydrogen
phosphate or phosphite anion contacting steps. In specific
embodiments, up to about 3-4% P.sub.2O.sub.5 content is achieved in
a single step.
[0069] Contact of the anion with the zeolite and kaolin derived
matrix is suitably conducted at a pH ranging from about 2 to about
8. The lower pH limit is selected to minimize loss of crystallinity
of the zeolite. The upper pH limit appears to be set by the effect
of the anion concentration. Suitable concentrations of the
dihydrogen phosphate or dihydrogen phosphite anion in the liquid
medium range from about 0.2 to about 10.0 weight percent anion.
[0070] In the above described procedure, the rare earth ion
exchange is performed prior to addition of the phosphorus
component. However, it will be understood that according to one or
more embodiments, it may be desirable to add a phosphorus component
prior to rare earth ion exchange. In other embodiments, it may be
desirable to add the phosphorus component both prior to rare earth
ion exchange and after rare earth ion exchange.
[0071] According to one or more embodiments, the catalyst comprises
from about 1% to about 5% phosphorus (P.sub.2O.sub.5), including 1,
2, 3, 4, and 5%. In specific embodiments, the catalyst comprises at
least 2% P.sub.2O.sub.5. A specific range is 2.5 to 3.5 wt. %
P.sub.2O.sub.5.
[0072] Without intending to be bound by theory, it is thought that
the sequential addition of a rare earth component followed by
addition of a phosphorus component produces microspheres that are
surface area stabilized. In other words, the catalytic microspheres
are stabilized to resist loss of surface area during FCC cracking.
It is believed that if the phosphorus component is added prior to
the addition of the rare earth component, and no further phosphorus
is added, the microspheres are not surface area stabilized. As used
herein, the term "surface area stabilized" refers to catalytic
microspheres that have an aged surface area that exceeds the aged
surface area of catalytic microspheres in which the rare earth
component and phosphorus component were not added sequentially. In
one or more embodiments, a phosphorus component is added prior to
the addition of a rare earth component, and then, after the rare
earth component is added, an additional phosphorus component is
added, such that the total phosphorus content is from about 1% to
about 5% P.sub.2O.sub.5, including 1, 2, 3, 4, 5%.
[0073] According to one or more embodiments, the selectivity
benefits of adding phosphorus result in enhanced metals
passivation, particularly when phosphorus is added to a catalyst
that contains transition alumina. In particular, in addition to
surface area stabilization, phosphorus addition to a transition
alumina-containing catalyst provides significant benefits,
including lower hydrogen and coke yield and higher activity.
Lowering hydrogen yields is beneficial in wet gas
compressor-limited processes.
[0074] Subsequent to the rare earth exchange and phosphorus
addition, catalyst composition is then dried and then calcined at a
temperature of from 800.degree.-1200.degree. F. The conditions of
the calcination are such that the unit cell size of the zeolite
crystals is not significantly reduced. Typically, the drying step,
after rare earth exchange is to remove a substantial portion of the
water contained within the catalyst.
[0075] The rare earth oxide-containing catalyst, subsequent to
calcination, is now further ion exchanged, typically by ammonium
ions to, again, reduce the sodium content to less than about 0.5
wt. % Na.sub.2O. The ammonium exchange can be repeated to ensure
that the sodium content is reduced to less than 0.5 wt. %
Na.sub.2O. Typically, the sodium content will be reduced to below
0.2 wt. % as Na.sub.2O. Subsequent to ammonium exchange, the
reduced sodium catalyst containing the Y-type zeolite and the
kaolin derived matrix can be contacted again with a medium
containing the phosphorus compounds as described above, with
respect to the first phosphorus treatment. The medium contains
sufficient phosphorus to provide a content of phosphorus as
P.sub.2O.sub.5 of at least 2.0 wt. % and, more typically, an amount
of phosphorus as P.sub.2O.sub.5 of 2.8 to 3.5 wt. % relative to the
catalyst, including zeolite and kaolin derived matrix. Temperatures
and pH conditions for the second phosphorus treatment are as in the
first treatment described above. After phosphorus treatment, the
impregnated catalyst is calcined again at temperatures of from
700.degree.-1500.degree. F.
[0076] The catalysts of the invention can also be used in
conjunction with additional V-traps. Thus, in one or more
embodiments, the catalyst further comprises a V-trap. The V-trap
can be selected from one or more conventional V-traps including,
but not limited to, MgO/CaO Without intending to be bound by
theory, it is thought that MgO/CaO interacts with V.sub.2O.sub.5
through an acid/base reaction to give vanadates.
[0077] A second aspect of the present invention pertains to a
method of cracking a hydrocarbon feed under fluid catalytic
cracking conditions. In one or more embodiments, the method
comprises contacting the hydrocarbon feed with the phosphorus
modified catalyst of one or more embodiments. In one or more
embodiments, the hydrocarbon feed is a resid feed. In one or more
embodiments, in a resid feed operation, one of Ni and V metals
accumulate on the catalyst, and the FCC catalyst composition is
effective to contact nickel and vanadium during cracking, thus
reducing coke and hydrogen yields.
[0078] Conditions useful in operating FCC units utilizing catalyst
of the invention are known in the art and are contemplated in using
the catalysts of the invention. These conditions are described in
numerous publications including Catal. Rev.-Sci. Eng., 18 (1),
1-150 (1978), which is herein incorporated by reference in its
entirety. The catalysts of one or more embodiments are particularly
useful in cracking residuum and resid-containing feeds.
[0079] A further aspect of the present invention pertains to a
method of manufacturing an FCC catalyst composition. In one or more
embodiments, the method comprises pre-forming a precursor
microsphere comprising non-zeolitic matrix material and alumina; in
situ crystallizing zeolite on the pre-formed microsphere to provide
a zeolite-containing microsphere; adding a rare earth component to
the zeolite-containing microsphere to provide a
rare-earth-containing microsphere; and adding a phosphorus
component to the rare-earth-containing microsphere to provide a
catalytic microsphere. In one or more embodiments, the phosphorus
is added by reacting/contacting the rare-earth-containing
microsphere with diammonium phosphate. In specific embodiments, the
rare earth component comprises lanthana, and the lanthana is
introduced to the zeolite-containing microsphere by ion
exchange.
[0080] In one or more embodiments, the method of manufacturing
further comprises adding a phosphorus component to the
zeolite-containing microsphere. In specific embodiments, the rare
earth and the phosphorus component are added sequentially in
separate steps.
[0081] In other embodiments, the method comprises adding a portion
of the phosphorus component, then ion exchanging with the rare
earth component, and then adding an additional phosphorus
component. It is noted that adding the rare earth component and the
phosphorus component at the same time may deleteriously affect
catalytic activity.
[0082] The invention is now described with reference to the
following examples.
EXAMPLES
Example 1
[0083] Calcined kaolin (mullite) (36.6 kg) slurry made to 49%
solids was added to 59% solids hydrous kaolin (25.9 kg), while
mixing, using a Cowles mixer. Next a 56% solids boehmite alumina
(14 kg) slurry was slowly added to the mixing clay slurry and was
allowed to mix for more than five minutes. The mixture was screened
and transferred to a spray dryer feed tank. The clay/boehmite
slurry was spray dried with sodium silicate injected in-line just
prior to entering the atomizer. Sodium silicate (20.2 kg, 3.22
modulus) was used at a metered ratio of 1.14 liter/min slurry: 0.38
liter/min silicate. The target particle size for the microspheres
was 80 microns. Binder sodium was removed from the formed
microspheres by slurrying the microspheres for thirty minutes and
maintaining the pH from 3.5-4 using sulfuric acid. Finally, the
acid neutralized microspheres were dried and calcined at
1350-1500.degree. F. for two hours. The microspheres were processed
to grow 60-65% zeolite Y using an in situ crystallization process.
A sample of crystallized NaY microspheres (250 g) was ion exchanged
to achieve a Na.sub.2O of 2.0% using ammonium nitrate. Rare earth
was then added to 2 wt. % REO. The rare earth exchanged sample was
calcined at 1000.degree. F. for 2 hours to stabilize the catalyst
and facilitate zeolitic sodium removal. After calcinations, a
series of ammonium nitrate ion exchanges was performed to <0.2
wt. % Na.sub.2O. Finally, with the reduced sodium, a second
calcination was done at 1100.degree. F. for 2 hours in order to
further stabilize the catalyst and reduce unit cell size. To
evaluate the resid catalyst in circulating riser unit, a sample (20
kg) was prepared following the process using a 25 gallon reactor
vessel and pan filters for the ion exchange and P treatments.
Calcinations were completed in covered trays in muffle ovens. The
catalyst composition is further impregnated with 3000 ppm of nickel
and 2500 ppm of vanadium and aged under cyclic reducing and
oxidizing conditions in the presence of steam at between
1350-1500.degree. F. The catalytic activity and selectivity of the
catalyst composition is determined using Advanced Cracking
Evaluation (ACE) reactors and protocols.
Example 2
[0084] Calcined kaolin (mullite) (36.6 kg) slurry made to 49%
solids was added to 59% solids hydrous kaolin (25.9 kg), while
mixing, using a Cowles mixer. Next a 56% solids boehmite alumina
(14 kg) slurry was slowly added to the mixing clay slurry and was
allowed to mix for more than five minutes. The mixture was screened
and transferred to a spray dryer feed tank. The clay/boehmite
slurry was spray dried with sodium silicate injected in-line just
prior to entering the atomizer. Sodium silicate (20.2 kg, 3.22
modulus) was used at a metered ratio of 1.14 liter/min slurry:0.38
liter/min silicate. The target particle size for the microspheres
was 80 microns. Binder sodium was removed from the formed
microspheres by slurrying the microspheres for thirty minutes and
maintaining the pH from 3.5-4 using sulfuric acid. Finally, the
acid neutralized microspheres were dried and calcined at
1350-1500.degree. F. for two hours. The microspheres were processed
to grow 60-65% zeolite Y using an in situ crystallization process.
A sample of crystallized NaY microspheres (250 g) was ion exchanged
to achieve a Na.sub.2O of 2.0% using ammonium nitrate. The sodium
adjusted sample was treated with phosphorus to 1.5% P.sub.2O.sub.5.
Rare earth (lanthanum) was then added to 2 wt. % REO. The
phosphorus and rare earth exchanged sample was calcined at
1000.degree. F. for 2 hours to stabilize the catalyst and
facilitate zeolitic sodium removal. After calcinations, a series of
ammonium nitrate ion exchanges was performed to <0.2 wt. %
Na.sub.2O. Once at desired sodium level, a second phosphorus
treatment was carried out to increase the total P.sub.2O.sub.5 to
3%. Finally, with the reduced sodium, a second calcination was done
at 1100.degree. F. for 2 hours in order to further stabilize the
catalyst and reduce unit cell size. To evaluate the P modified
resid catalyst in circulating riser unit, a sample (20 kg) was
prepared following the process using a 25 gallon reactor vessel and
pan filters for the ion exchange and P treatments. Calcinations
were completed in covered trays in muffle ovens. The catalyst
composition is further impregnated with 3000 ppm of nickel and 2500
ppm of vanadium and aged under cyclic reducing and oxidizing
conditions in the presence of steam at between 1350-1500.degree. F.
The catalytic activity and selectivity of the catalyst composition
is determined using Advanced Cracking Evaluation (ACE) reactors and
protocols.
Example 3
[0085] The catalyst of Example 1 is combined with a separate
particle vanadium trap prior to metals impregnation and
deactivation and the catalytic activity and selectivity of the
catalyst composition is determined using Advanced Cracking
Evaluation (ACE) reactors and protocols.
Example 4
[0086] The catalyst of Example 2 is combined with a separate
particle vanadium trap prior to metals impregnation deactivation
and the catalytic activity and selectivity of the catalyst
composition is determined using Advanced Cracking Evaluation (ACE)
reactors and protocols.
[0087] Results
[0088] Characterization and catalytic testing results at 70%
conversion are presented in Table
TABLE-US-00001 TABLE 4 ACE results On a Resid Feed Example 2
-Example 1 Example 4 Example 3 (Inven- (Compar- (Inven- (Compar-
tion) ative) tion) ative) H.sub.2 0.29 0.38 0.20 0.30 Propylene
4.34 4.15 4.57 4.56 LPG 14.42 14.21 15.08 14.68 Total C4 16.47
16.41 17.01 16.76 Gasoline 43.98 43.72 44.25 44.03 LCO 15.29 15.98
15.65 15.92 HCO 14.71 14.02 14.35 14.08 Coke 9.54 9.88 8.74 9.21
Cat/Oil 3.06 2.81 3.44 3.34 Activity 4.52 4.56 4.27 4.25 @ C/O =
7.7 Conversion 81.88 82.02 81.04 80.94 @ C/O = 7.7
[0089] ACE testing of the catalyst impregnated with nickel and
vanadium reveal that at 70 wt. % conversion relative to Example 1,
Example 2 gives: 24% lower hydrogen, 3% lower coke, along with 0.6%
higher gasoline, and 4.5% higher propylene, with nearly equivalent
LPG and total C4 at equivalent activity.
[0090] Example 3 combines Example 1 with a separate particle
vanadium trap, and Example 4 combines Example 2 with a separate
particle vanadium trap. The results indicate that the catalyst of
Example 4 offers benefits over the catalyst of Example 3 including:
33% lower hydrogen and 5% lower coke. Examples 5 and 6
[0091] The Examples 3 and 4 described above were prepared according
to the procedure explained above and were tested in a pilot-scale
FCC unit using two different types of feeds after loading with
contaminant metals (3000 ppm Ni and 2500 ppm V) followed by
hydrothermal deactivation.
[0092] FIGS. 1-2 present the results for coke and H.sub.2 for a
resid feed. FIGS. 3-4 present the results for coke and H.sub.2 for
a lighter (VGO) feed.
Example 7
Double Stage Phosphorus Addition
[0093] Following the process in Example 2, a sample was prepared
having a rare earth content of 2 percent by weight and phosphorus
total was 3% P.sub.2O.sub.5.
Example 8
Single Stage Phosphorus Addition
[0094] Similar to the process in Example 2, a sample was prepared,
whereby a phosphorus addition was employed only during the second
application stage as described in example 2.Rare earth was 2% REO
and phosphorus total was 3% P.sub.2O.sub.5 added in one stage.
Example 9
Comparative Example (No Phosphorus)
[0095] Using the microspheres of Example 1, an FCC catalyst was
prepared having a rare earth content of 2 percent by weight.
[0096] The three samples (Examples 7, 8, and 9) were prepared for
ACE catalytic evaluation using the following protocol:
[0097] Presteamed at 1350.degree. F./2 hours/100% steam
[0098] Impregnated with 3000 ppm Ni and 3000 ppm V
[0099] Steamed 1500.degree. F./5 hour/90% steam and 10% air
[0100] Catalytic evaluation is presented in Table V. The results
are shown at constant 70 wt. % conversion.
TABLE-US-00002 TABLE 2 ACE Results Example 9 Example 7 Example 8 0%
Single Stage 3% Double Stage 3% P.sub.2O.sub.5 P.sub.2O.sub.5
P.sub.2O.sub.5 H.sub.2 1.34 1.09 1.23 Propylene 4.07 4.30 4.19 LPG
13.19 14.62 14.18 Gasoline 42.88 42.91 43.07 LCO 17.48 15.85 16.57
HCO 12.53 14.16 13.43 Coke 10.34 9.22 9.32 Cat/Oil 7.43 6.34 6.75
Activity 2.39 2.60 2.53 @ C/O = 7.7 Conversion 70.47 72.22 71.64 @
C/O = 7.7
[0101] Examples 7 and 8 show preferred hydrogen and coke yields
compared to Example 9.
[0102] All references, including publications, patent applications,
and patents, cited herein are hereby incorporated by reference for
all purposes to the same extent as if each reference were
individually and specifically indicated to be incorporated by
reference and were set forth in its entirety herein.
[0103] The use of the terms "a" and "an" and "the" and similar
referents in the context of describing the materials and methods
discussed herein (especially in the context of the following
claims) are to be construed to cover both the singular and the
plural, unless otherwise indicated herein or clearly contradicted
by context. Recitation of ranges of values herein are merely
intended to serve as a shorthand method of referring individually
to each separate value falling within the range, unless otherwise
indicated herein, and each separate value is incorporated into the
specification as if it were individually recited herein. All
methods described herein can be performed in any suitable order
unless otherwise indicated herein or otherwise clearly contradicted
by context. The use of any and all examples, or exemplary language
(e.g., "such as") provided herein, is intended merely to better
illuminate the materials and methods and does not pose a limitation
on the scope unless otherwise claimed. No language in the
specification should be construed as indicating any non-claimed
element as essential to the practice of the disclosed materials and
methods.
[0104] Reference throughout this specification to "one embodiment,"
"certain embodiments," "one or more embodiments" or "an embodiment"
means that a particular feature, structure, material, or
characteristic described in connection with the embodiment is
included in at least one embodiment of the invention. Thus, the
appearances of the phrases such as "in one or more embodiments,"
"in certain embodiments," "in one embodiment" or "in an embodiment"
in various places throughout this specification are not necessarily
referring to the same embodiment of the invention. Furthermore, the
particular features, structures, materials, or characteristics may
be combined in any suitable manner in one or more embodiments.
[0105] Although the invention herein has been described with
reference to particular embodiments, it is to be understood that
these embodiments are merely illustrative of the principles and
applications of the present invention. It will be apparent to those
skilled in the art that various modifications and variations can be
made to the method and apparatus of the present invention without
departing from the spirit and scope of the invention. Thus, it is
intended that the present invention include modifications and
variations that are within the scope of the appended claims and
their equivalents.
* * * * *