U.S. patent application number 10/723355 was filed with the patent office on 2004-07-08 for desulfurization and novel sorbents for same.
Invention is credited to Johnson, Byron G., Kidd, Dennis R., Slater, Peter N., Sughrue, Edward L. II.
Application Number | 20040129607 10/723355 |
Document ID | / |
Family ID | 46300415 |
Filed Date | 2004-07-08 |
United States Patent
Application |
20040129607 |
Kind Code |
A1 |
Slater, Peter N. ; et
al. |
July 8, 2004 |
Desulfurization and novel sorbents for same
Abstract
A sorbent composition is provided which can be used in the
desulfurization of a hydrocarbon-containing fluid such as cracked
gasoline or diesel fuel. The sorbent composition contains a support
component and a promoter component with the promoter component
being present as a skin on said support component. Such sorbent
composition is prepared by a process of impregnating a support
component with a promoter component, wherein the promoter component
has been melted under a melting condition, followed by drying,
calcining, and reducing to thereby provide the sorbent composition.
A process for the removal of sulfur from a hydrocarbon stream,
wherein the hydrocarbon stream is a combination of cracked gasoline
and diesel fuel, is also disclosed.
Inventors: |
Slater, Peter N.;
(Bartlesville, OK) ; Johnson, Byron G.;
(Bartlesville, OK) ; Sughrue, Edward L. II;
(Bartlesville, OK) ; Kidd, Dennis R.; (Dewey,
OK) |
Correspondence
Address: |
RICHMOND, HITCHCOCK
FISH & DOLLAR
P.O. Box 2443
Bartlesville
OK
74005
US
|
Family ID: |
46300415 |
Appl. No.: |
10/723355 |
Filed: |
November 26, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10723355 |
Nov 26, 2003 |
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09525588 |
Mar 15, 2000 |
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6683024 |
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Current U.S.
Class: |
208/247 ; 208/15;
208/16; 208/245; 208/248; 208/299; 208/305 |
Current CPC
Class: |
C10G 2300/202 20130101;
C10G 2400/08 20130101; B01J 20/18 20130101; B01J 20/3289 20130101;
B01J 20/103 20130101; C10G 2400/04 20130101; C10G 25/12 20130101;
B01J 20/3236 20130101; B01J 20/3078 20130101; C10G 25/02 20130101;
B01J 20/28004 20130101; B01J 20/3433 20130101; B01J 20/3458
20130101; B01J 20/06 20130101; B01J 20/12 20130101; C10G 25/003
20130101; B01J 20/20 20130101; B01J 20/08 20130101; C10G 25/05
20130101; B01J 20/28016 20130101; B01J 2220/56 20130101; B01J
20/3204 20130101; B01J 20/3483 20130101; B01J 2220/42 20130101;
C10G 2400/02 20130101; B01J 20/3007 20130101; B01J 20/3293
20130101; C10G 2400/06 20130101; B01J 20/10 20130101 |
Class at
Publication: |
208/247 ;
208/248; 208/245; 208/015; 208/016; 208/299; 208/305 |
International
Class: |
C10G 025/00; C10G
025/12 |
Claims
What is claimed is:
1. A process for the removal of sulfur from a hydrocarbon stream,
wherein said hydrocarbon stream is a combination of cracked
gasoline and diesel fuel, said process comprising: (a) contacting
said hydrocarbon stream with a composition comprising a zinc oxide,
a silica-containing material, an aluminum-containing material
selected from the group consisting of alumina, aluminate, and
combinations thereof, and a promoter wherein at least a portion of
said promoter is present as a reduced valence promoter and in an
amount which will effect the removal of sulfur from said
hydrocarbon stream in a desulfurization zone under conditions such
that there is formed a desulfurized hydrocarbon stream and a
sulfurized composition; (b) separating said desulfurized
hydrocarbon stream from said sulfurized composition thereby forming
a separated desulfurized hydrocarbon stream and a separated
sulfurized composition; (c) regenerating at least a portion of said
separated sulfurized composition in a regeneration zone so as to
remove at least a portion of the sulfur contained therein and/or
thereon thereby forming a regenerated composition; (d) reducing
said regenerated composition in an activation zone so as to provide
a reduced composition having a reduced valence promoter content
therein which will effect the removal of sulfur from a hydrocarbon
stream when contacted with same; and thereafter (e) returning at
least a portion of said reduced composition to said desulfurization
zone.
2. A process in accordance with claim 1, wherein said diesel fuel
is light cycle oil.
3. A process in accordance with claim 1 wherein said
desulfurization in step (a) is carried out at a temperature in the
range of from about 100.degree. F. to about 1000.degree. F. and a
pressure in the range of from about 15 to about 1500 psia for a
time sufficient to effect the removal of sulfur from said
stream.
4. A process in accordance with claim 1 wherein said
desulfurization in step (a) is carried out at a temperature in the
range of from 400.degree. F. to 900.degree. F.
5. A process in accordance with claim 1 wherein said regeneration
in step (c) is carried out at a temperature in the range of from
about 100.degree. F. to about 1500.degree. F. and a pressure in the
range of from about 10 to about 1500 psia for a time sufficient to
effect the removal of at least a portion of the sulfur from said
separated sulfurized composition.
6. A process in accordance with claim 1 wherein air is employed in
step (c) as a regeneration agent in said regeneration zone.
7. A process in accordance with claim 1 wherein said regenerated
composition from step (c) is subjected to reduction with hydrogen
in step (d) in said reduction zone which is maintained at a
temperature in the range of from about 100.degree. F. to about
1500.degree. F. and at a pressure in the range of from about 15 to
about 1500 psia and for a period of time sufficient to effect a
reduction of the valence of the promoter content of said
regenerated composition.
8. A process in accordance with claim 1 wherein said separated
sulfurized composition from step (b) is stripped prior to
introduction into said regeneration zone in step (c).
9. A process in accordance with claim 1 wherein said regenerated
composition from step (c) is stripped prior to introduction to said
reduction zone in step (d).
10. The cracked gasoline product of claim 1.
11. The diesel fuel product of claim 1.
Description
[0001] This is a Continuation-in-Part of application Ser. No.
09/525,588, filed Mar. 15, 2000, now allowed.
BACKGROUND OF THE INVENTION
[0002] This invention relates to a sorbent composition, a process
of making a sorbent composition, and to a process of using a
sorbent composition for the removal of sulfur from a
hydrocarbon-containing fluid.
[0003] The need for cleaner burning fuels has resulted in a
continuing world-wide effort to reduce sulfur levels in
hydrocarbon-containing fluids such as gasoline and diesel fuels.
The reduction of sulfur in such hydrocarbon-containing fluids is
considered to be a means for improving air quality because of the
negative impact the sulfur has on the performance of
sulfur-sensitive items such as automotive catalytic converters. The
presence of oxides of sulfur in automotive engine exhaust inhibits
and may irreversibly poison noble metal catalysts in the converter.
Emissions from an inefficient or poisoned converter contain levels
of non-combusted, non-methane hydrocarbons, oxides of nitrogen, and
carbon monoxide. Such emissions are catalyzed by sunlight to form
ground level ozone, more commonly referred to as smog.
[0004] Most of the sulfur in a hydrocarbon-containing fluid such as
gasoline comes from thermally processed gasolines. Thermally
processed gasolines such as, for example, thermally cracked
gasoline, visbreaker gasoline, coker gasoline and catalytically
cracked gasoline (hereinafter collectively referred to as
"cracked-gasoline") contains, in part, olefins, aromatics, sulfur,
and sulfur-containing compounds.
[0005] Since most gasolines, such as for example automobile
gasolines, racing gasolines, aviation gasolines, boat gasolines,
and the like contain a blend of, at least in part,
cracked-gasoline, reduction of sulfur in cracked-gasoline will
inherently serve to reduce the sulfur levels in most gasolines such
as, for example, automobile gasolines, racing gasolines, aviation
gasolines, boat gasolines, and the like.
[0006] The public discussion about gasoline sulfur has not centered
on whether or not sulfur levels should be reduced. A consensus has
emerged that lower sulfur gasoline reduces automotive emissions and
improves air quality. Thus, the real debate has focused on the
required level of reduction, the geographical areas in need of
lower sulfur gasoline, and the time frame for implementation.
[0007] As the concern over the impact of automotive air pollution
continues, it is clear that further efforts to reduce the sulfur
levels in hydrocarbon-containing fluids such as gasolines, more
particularly automotive gasolines, will be required. While the
current automotive gasoline products contain about 330 parts per
million (ppm) sulfur by weight, the U. S. Environmental Protection
Agency recently issued regulations requiring the average sulfur
content in gasolines to be less than 30 ppm average with an 80 ppm
maximum. By 2006, the standards will effectively require every
blend of gasoline sold in the United States to meet the 30 ppm
level.
[0008] In addition to the need to be able to produce low sulfur
content automotive fuels, there is also a need for a process which
will have a minimal effect on the olefin content of such fuels so
as to maintain the octane number (both research and motor octane
number). Such a process would be desirable since saturation of
olefins greatly affects the octane number. Such adverse effect on
olefin content is generally due to the severe condition normally
employed, such as during hydrodesulfurization, to remove thiophenic
compounds (such as, for example, thiophenes, benzothiophenes, alkyl
thiophenes, alkylbenzothiophenes, alkyl dibenzothiophenes and the
like) which are some of the most difficult sulfur-containing
compounds to be removed from cracked-gasoline. In addition, there
is a need to avoid a system wherein the conditions are such that
the aromatic content of the cracked-gasoline is also lost through
saturation. Thus, there is a need for a process wherein
desulfurization is achieved and the octane number is
maintained.
[0009] In addition to the need for removal of sulfur from
hydrocarbon-containing fluids such as cracked-gasoline, there is
also presented to the petroleum industry a need to reduce the
sulfur content in other hydrocarbon-containing fluids such as
diesel fuel including light cycle oils. In removing sulfur from
diesel fuel by hydrodesulfurization, the cetane is improved but
there is a large cost in hydrogen consumption. Such hydrogen is
consumed by both hydrodesulfurization and aromatic hydrogenation
reactions.
[0010] Thus, there is a need for a process of desulfurization
without a significant consumption of hydrogen so as to provide a
more economical process for the treatment of hydrocarbon-containing
fluids such as cracked gasoline and diesel fuel including light
cycle oils.
[0011] As a result of the lack of success in providing a successful
and economically feasible process for the reduction of sulfur
levels in hydrocarbon-containing fluids such as cracked-gasoline
and diesel fuel including light cycle oils, it is apparent that
there is still a need for a better process for the desulfurization
of such hydrocarbon-containing fluids which has minimal effect on
octane levels while achieving high levels of sulfur removal.
[0012] Further, prior art processes to produce compositions
containing promoter components generally involve adding the
promoter components by spray impregnation techniques which utilize
an aqueous or non-aqueous solvent such as water. Such spray
impregnation techniques are costly and time-consuming.
Consequently, a process to produce a sorbent composition which
involves adding a promoter component(s) without utilizing a spray
impregnation technique or substantial quantities of an aqueous or
non-aqueous solvent such as water would be of significant
contribution to the art and to the economy.
SUMMARY OF THE INVENTION
[0013] An object of the present invention is to provide a sorbent
composition that can be used for the removal of sulfur from a
hydrocarbon-containing fluid such as cracked-gasoline or diesel
fuel including light cycle oils.
[0014] Another object of the present invention is to provide a
sorbent composition comprising a promoter component selected from
the group consisting of metals, metal oxides, and the like and
combinations thereof distributed as a "skin" on the sorbent
composition.
[0015] Yet another object of the present invention is to provide a
sorbent composition having a reduced amount of metal or metal oxide
components exhibiting a high reactivity to remove sulfur from
hydrocarbon-containing fluids compared to a sorbent composition
having a greater amount of such metal or metal oxide
components.
[0016] Still another object of the present invention is to provide
a method of making a novel sorbent composition which is useful in
the desulfurization of a hydrocarbon-containing fluid such as
cracked-gasoline and/or diesel fuel including light cycle oils.
[0017] Still yet another object of the present invention is to
provide a method of making a novel sorbent composition which is
useful in the desulfurization of a hydrocarbon-containing fluid,
such as cracked-gasoline or diesel fuel including light cycle oils,
which does not involve a spray impregnation technique, such as a
spray impregnation technique which utilizes an aqueous or
non-aqueous solvent such as water, when adding a promoter
component(s) to such composition(s).
[0018] A further object of the present invention is to employ such
novel sorbent composition(s) and a process(es) for the removal of
sulfur, such as that found in sulfur-containing compounds, from a
hydrocarbon-containing fluid, such as cracked-gasoline or diesel
fuel including light cycle oils, which minimizes the consumption of
hydrogen and minimizes the saturation of olefins and aromatics
contained in such hydrocarbon-containing fluid.
[0019] A still further object of the present invention is to
provide a desulfurized cracked-gasoline that contains less than
about 100 parts per million of sulfur based on the weight of the
desulfurized cracked-gasoline and which contains essentially the
same amount of olefins and aromatics as are in the cracked-gasoline
from which such desulfurized cracked-gasoline was made.
[0020] The present invention is based upon our discovery that
through the utilization of a "skin" distribution of a promoter
component, selected from the group consisting of metals, metal
oxides, and the like and combinations thereof, in a substantially
reduced valence state, preferably a zero valence state, onto a
sorbent composition there is achieved a novel sorbent composition
which permits the ready removal of sulfur from
hydrocarbon-containing fluids such as cracked-gasoline and diesel
fuel including light cycle oils with a minimal effect on the octane
rating of the treated hydrocarbon-containing fluid.
[0021] In one aspect of the present invention there is provided a
novel sorbent composition(s) suitable for the desulfurization of a
hydrocarbon-containing fluid, such as cracked-gasoline or diesel
fuel including light cycle oils. Such novel sorbent composition(s)
comprises a support component and a "skin-distributed" promoter
component selected from the group consisting of metals, metal
oxides, and the like and combinations thereof wherein the valance
of such promoter component, distributed as a skin, is substantially
reduced and such reduced-valence skin-distributed promoter
component is present in an amount which is effective in the removal
of sulfur from a hydrocarbon-containing fluid.
[0022] In accordance with another aspect of the present invention,
there is provided a process(es) for the preparation of a novel
sorbent composition(s) which comprises: contacting components of a
support component, preferably such support component comprises zinc
oxide, silica, and alumina, to form a mixture selected from the
group consisting of a wet mix, a dough, a paste, a slurry, and the
like; particulating such mixture so as to form a particulate
selected from the group consisting of a granule, an extrudate, a
tablet, a sphere, a pellet, a microsphere, and the like; drying
such particulate to form a dried particulate; calcining such dried
particulate to form a calcined particulate; distributing a promoter
component selected from the group consisting of metals, metal
oxides, and the like and combinations thereof as a skin upon such
dried and calcined particulate to form a promoted particulate;
drying such promoted particulate to form a dried promoted
particulate; calcining such dried promoted particulate to form a
calcined promoted particulate; and reducing such calcined promoted
particulate with a suitable reducing agent, such as hydrogen, so as
to produce a sorbent composition having a substantially
reduced-valence promoter component distributed as a skin on such
sorbent composition in an amount which is effective in removing
sulfur from a hydrocarbon-containing fluid. Such process of
distributing a promoter component as a skin upon such dried and
calcined particulate utilizes a novel melting method which does not
require the use of a substantial quantity of an aqueous or
non-aqueous solvent such as water.
[0023] In accordance with a further aspect of the present
invention, there is provided a process(es) for the desulfurization
of a hydrocarbon-containing fluid selected from the group
consisting of cracked-gasoline, diesel fuel, light cycle oils and
the like and combinations thereof which comprises desulfurizing in
a desulfurization zone such hydrocarbon-containing fluid with a
sorbent composition, separating the desulfurized
hydrocarbon-containing fluid from the resulting sulfurized sorbent
composition, regenerating at least a portion of the resulting
sulfurized sorbent composition to produce a regenerated,
desulfurized sorbent composition; activating at least a portion of
the regenerated, desulfurized sorbent composition to produce an
activated, regenerated, desulfurized sorbent composition; and
thereafter returning at least a portion of the activated,
regenerated, desulfurized sorbent composition(s) to the
desulfurization zone.
[0024] Other objectives and advantages of the present invention
will be apparent from the detailed description of the invention and
the appended claims.
DETAILED DESCRIPTION OF THE INVENTION
[0025] The term "gasoline" denotes a mixture of hydrocarbons
boiling in the range of from about 100.degree. F. to about
400.degree. F., or any fraction thereof. Examples of suitable
gasoline include, but are not limited to, hydrocarbon streams in
refineries such as naphtha, straight-run naphtha, coker naphtha,
catalytic gasoline, visbreaker naphtha, alkylate, isomerate,
reformate, and the like and combinations thereof.
[0026] The term "cracked-gasoline" denotes a mixture of
hydrocarbons boiling in the range of from about 100.degree. F. to
about 400.degree. F., or any fraction thereof, that are products
from either thermal or catalytic processes that crack larger
hydrocarbon molecules into smaller molecules. Examples of suitable
thermal processes include, but are not limited to, coking, thermal
cracking, visbreaking and the like and combinations thereof.
Examples of suitable catalytic cracking processes include, but are
not limited to fluid catalytic cracking, heavy oil cracking, and
the like and combinations thereof. Thus, examples of suitable
cracked-gasoline include, but are not limited to, coker gasoline,
thermally cracked gasoline, visbreaker gasoline, fluid
catalytically cracked gasoline, heavy oil cracked gasoline, and the
like and combinations thereof. In some instances, the
cracked-gasoline may be fractionated and/or hydrotreated prior to
desulfurization when used as a hydrocarbon-containing fluid in a
process(es) of the present invention.
[0027] The term "diesel fuel" denotes a mixture of hydrocarbons
boiling in the range of from about 300.degree. F. to about
750.degree. F., or any fraction thereof. Examples of suitable
diesel fuels include, but are not limited to, light cycle oil,
kerosene, jet fuel, straight-run diesel, hydrotreated diesel, and
the like and combinations thereof.
[0028] The term "sulfur" denotes sulfur in any form such as
elemental sulfur or a sulfur compound normally present in a
hydrocarbon-containing fluid such as cracked gasoline or diesel
fuel. Examples of sulfur which can be present during the
desulfurization process(es) disclosed herein, usually contained in
a hydrocarbon-containing fluid, include, but are not limited to,
hydrogen sulfide, carbonyl sulfide (COS), carbon disulfide
(CS.sub.2), mercaptans (RSH), organic sulfides (R--S--R), organic
disulfides (R--S--S--R), thiophene, substituted thiophenes, organic
trisulfides, organic tetrasulfides, benzothiophene, alkyl
thiophenes, alkyl benzothiophenes, alkydibenzothiophenes, and the
like and combinations thereof as well as the heavier molecular
weights of same which are normally present in a diesel fuel of the
types contemplated for use in a process(es) of the present
invention, wherein each R can be an alkyl or cycloalkyl or aryl
group containing one carbon atom to ten carbon atoms.
[0029] The term "fluid" denotes gas, liquid, vapor, and
combinations thereof.
[0030] The term "gaseous" denotes that state in which the
hydrocarbon-containing fluid, such as cracked-gasoline or diesel
fuel, is primarily in a gas or vapor phase.
[0031] The term "skin" denotes the exterior surface of the sorbent
composition which can contain a promoter component selected from
the group consisting of metals, metal oxides, and the like and
combinations thereof. The skin can be any thickness as long as such
thickness can promote the desulfurization process(es) disclosed
herein. Generally, the thickness of the skin can be in the range of
from about 1 micron to about 400 microns, preferably in the range
of from about 5 microns to about 300 microns, more preferably in
the range of from about 5 microns to about 250 microns, and, most
preferably, in the range of from 5 microns to 200 microns.
Preferably, the promoter component is concentrated as a skin on the
sorbent composition whereas other components of the support
component, preferably comprising zinc oxide, silica, and alumina,
are distributed throughout the sorbent composition.
[0032] The term "support component" denotes any component or
combination of such components which can be used as a support for a
sorbent composition(s) of the present invention to help promote the
desulfurization process(es) disclosed herein. Examples of a
suitable support component include, but are not limited to, zinc
oxide and any suitable inorganic and organic carriers and the like
and combinations thereof. Examples of suitable inorganic carriers
include, but are not limited to, silica, silica gel, alumina, clays
such as attapulgus clay, china clay, diatomaceous earth, kaolin,
kieselguhr, aluminum silicate, silica-alumina, titania, zirconia,
zinc aluminate, zinc titanate, zinc silicate, calcium aluminate,
calcium silicate, magnesium silicate, magnesium aluminate,
magnesium titanate, synthetic zeolites, natural zeolites, and the
like and combinations thereof. Examples of suitable organic
carriers include, but are not limited to, activated carbon, coke,
charcoal, carbon-containing molecular sieves, and the like and
combinations thereof. A preferred support component comprises zinc
oxide, silica, and alumina.
[0033] The term "promoter component" denotes any component which
can be added to a sorbent composition of the present invention to
help promote the desulfurization process(es) disclosed herein.
Examples of suitable promoter components include, but are not
limited to, metals, metal oxides, and the like and combinations
thereof.
[0034] The term "metal" denotes metal in any form such as elemental
metal or a metal-containing compound.
[0035] The term "metal oxide" denotes metal oxide in any form such
as a metal oxide or a metal oxide precursor.
[0036] During the preparation of a sorbent composition(s) of the
present invention, the promoter component selected from the group
consisting of metals, metal oxides, and the like and combinations
thereof may initially be in the form of a metal-containing
compound(s) and/or a metal oxide precursor(s). It should be
understood that when the promoter component is initially a
metal-containing compound(s) and/or a metal oxide precursor(s), a
portion of, or all of, such compound(s) and/or precursor(s) may be
converted to the corresponding metal or metal oxide of such
compound(s) and/or precursor(s) during the inventive process(es)
disclosed herein.
[0037] The term "reduced-valence promoter component" denotes that a
substantial portion of the valence of such promoter component is
reduced to a value of less than 3, preferably to a value of
zero.
[0038] A sorbent composition(s) of the present invention
desulfurizes more effectively when the skin is relatively thin
(such as the most preferable skin thickness of 5 microns to 200
microns) than when the skin is thicker (such as greater than 400
microns). Thus, there is a significant benefit, better or more
desulfurization, by preparing a sorbent composition with a thin
skin, rather than a thick skin. Further, there is significant
benefit, better or more desulfurization, by preparing a sorbent
composition with a skin than a sorbent composition without a
skin.
[0039] One can use any suitable method(s) or manner known in the
art to determine the concentration of the promoter component in the
skin of the sorbent composition. Determining the concentration of
the promoter component in the skin of the sorbent composition also
helps in determining the thickness of the skin. One technique
currently favored is the electron microprobe which is known to one
skilled in the art.
[0040] The present invention is based upon the discovery of
applicants that a reduced-valence promoter component distributed as
a skin on a particulate composition comprising a support component,
preferably such support component comprises zinc oxide, silica, and
alumina, results in a sorbent composition which permits the removal
of sulfur from a hydrocarbon-containing fluid, such as
cracked-gasoline or diesel fuels, without having a significant
adverse effect on the olefin content of such treated
hydrocarbon-containing fluid, thus avoiding a significant reduction
in octane values of such treated hydrocarbon-containing fluid.
Moreover, the use of a novel sorbent composition(s) of the present
invention results in a significant reduction of the sulfur content
of the treated hydrocarbon-containing fluid.
[0041] When a support component generally comprising zinc oxide and
any inorganic or organic carrier, preferably comprising zinc oxide,
silica and alumina, is used, the zinc oxide used in the preparation
of a sorbent composition of the present invention can either be in
a form of zinc oxide such as powdered zinc oxide, or in the form of
one or more zinc compounds that are convertible to zinc oxide under
the conditions of preparation described herein. Examples of
suitable zinc compounds include, but are not limited to, zinc
sulfide, zinc sulfate, zinc hydroxide, zinc carbonate, zinc
acetate, zinc nitrate, and the like and combinations thereof.
Preferably, the zinc oxide is in the form of powdered zinc
oxide.
[0042] When a preferred support component comprising zinc oxide,
silica, and alumina is used, the silica used in the preparation of
a sorbent composition of the present invention may be either in the
form of silica or in the form of one or more silicon compounds. Any
suitable type of silica may be employed in preparing a sorbent
composition of the present invention. Examples of suitable types of
silica include, but are not limited to, diatomite, silicalite,
silica colloid, flame-hydrolyzed silica, hydrolyzed silica, silica
gel, precipitated silica and the like and combinations thereof,
with diatomite being presently preferred. In addition, silicon
compounds that are convertible to silica such as silicic acid,
sodium silicate, ammonium silicate and the like and combinations
thereof can also be employed. Preferably, the silica is in the form
of diatomite.
[0043] When a preferred support component comprising zinc oxide,
silica, and alumina is used, the alumina used in preparing a
sorbent composition of the present invention can be any suitable
commercially available alumina material including, but not limited
to, colloidal alumina solutions and, generally, those alumina
compounds produced by the dehydration of alumina hydrates.
[0044] The promoter component used in preparing a sorbent
composition of the present invention can be any metal, metal oxide,
and the like and combinations thereof in any form which is
effective in desulfurizing a hydrocarbon-containing fluid according
to a process(es) disclosed herein. Generally such promoter
component is selected from the group consisting of metals, metal
oxides, and the like and combinations thereof including compounds
which contain such metals and metal oxides. Examples of suitable
metals include, but are not limited to, cobalt, nickel, iron,
manganese, copper, zinc, molybdenum, tungsten, silver, tin,
vanadium, antimony, and the like and combinations thereof. Examples
of suitable metal oxides include, but are not limited to, cobalt
oxides, nickel oxides, iron oxides, manganese oxides, copper
oxides, zinc oxides, molybdenum oxides, tungsten oxides, silver
oxides, tin oxides, vanadium oxides, antimony oxides, and the like
and combinations thereof. Generally such metals are contained in
metal-containing compounds which can be used to distribute the
metal of such metal-containing compounds as a skin on the surface
of a dried and calcined particulate material to thereby form a
dried and calcined promoted particulate material which can then be
further dried and calcined, and preferably reduced, to thereby form
a sorbent composition of the present invention.
[0045] Some examples of the form which such metals can be in
include, but are not limited to, metal acetates, metal carbonates,
metal nitrates, metal sulfates, metal thiocyanates, and the like
and combinations thereof. Preferably, the promoter component is
selected from the group consisting of nickel, cobalt, and the like
and combinations thereof. More preferably, the promoter component
is nickel. In a preferred method of making process of the present
invention, the sorbent composition is promoted with a precursor of
a nickel oxide such as nickel nitrate, more preferably nickel
nitrate hexahydrate.
[0046] When the support component comprises zinc oxide and any
inorganic or organic carrier, preferably comprising zinc oxide,
silica and alumina, the zinc oxide will generally be present in the
sorbent composition in an amount in the range of from about 10 to
about 90 weight percent zinc oxide based on the total weight of the
sorbent composition, preferably in an amount in the range of from
about 15 to about 60 weight percent zinc oxide and, more
preferably, in an amount in the range of from 20 to 55 weight
percent zinc oxide.
[0047] When the support component comprises the preferred support
component comprising zinc oxide, silica, and alumina, the silica
will generally be present in the sorbent composition in an amount
in the range of from about 5 to about 85 weight percent silica
based on the total weight of the sorbent composition, preferably in
an amount in the range of from about 20 to about 60 weight percent
silica and, more preferably, in an amount in the range of from 25
to 55 weight percent silica.
[0048] When the support component comprises the preferred support
component comprising zinc oxide, silica, and alumina, the alumina
will generally be present in the sorbent composition in an amount
in the range of from about 5 to about 30 weight percent alumina
based on the total weight of the sorbent composition, preferably in
an amount in the range of from about 5 to about 20 weight percent
alumina and, more preferably, in an amount in the range of from 5
to 15 weight percent alumina.
[0049] The promoter component will generally be present in the
sorbent composition in an amount in the range of from about 5 to
about 50 weight percent promoter component based on the total
weight of the sorbent composition, preferably in an amount in the
range of from about 8 to about 40 weight percent promoter component
and, more preferably, in an amount in the range of from 10 to 30
weight percent promoter component. When the promoter component
comprises a combination of metals, metal oxides, and the like, such
as a preferred bimetallic promoter component, the bimetallic
promoter component should comprise a weight ratio of the two metals
forming such bimetallic promoter component in the range of from
about 20:1 to about 1:20. In a preferred embodiment of the present
invention, the promoter component is a bimetallic promoter
component comprising nickel and cobalt in a weight ratio of about
1:1.
[0050] In the manufacture of a sorbent composition of the present
invention, the support component is generally prepared by combining
the components of the support component, generally zinc oxide and
any inorganic or organic carrier, preferably zinc oxide, silica and
alumina, together in appropriate proportions by any suitable
method(s) or manner which provides for the intimate mixing of such
components to thereby provide a substantially homogeneous mixture
comprising zinc oxide and any inorganic or organic carrier,
preferably a substantially homogeneous mixture comprising zinc
oxide, silica and alumina. Any suitable means for mixing the
components of the support component, preferably zinc oxide, silica,
and alumina, can be used to achieve the desired dispersion of such
components. Examples of suitable means for mixing include, but are
not limited to, mixing tumblers, stationary shells or troughs,
Muller mixers, which are of the batch or continuous type, impact
mixers, and the like. It is presently preferred to use a Muller
mixer as the means for mixing the components of the support
component, preferably comprising zinc oxide, silica, alumina.
[0051] The components of the support component, generally zinc
oxide and any inorganic or organic carrier, preferably zinc oxide,
silica and alumina, are mixed to provide a resulting mixture which
can be in a form selected from the group consisting of wet mix,
dough, paste, slurry and the like. Such resulting mixture can then
be shaped to form a particulate(s) selected from the group
consisting of a granulate, an extrudate, a tablet, a sphere, a
pellet, or a micro-sphere. For example, if the resulting mixture is
in the form of a wet mix, the wet mix can be densified, dried under
a drying condition as disclosed herein, calcined under a calcining
condition as disclosed herein, and thereafter shaped, or
particulated, through the granulation of the densified, dried,
calcined mix to form granulates. Also for example, when the mixture
of the components of the support component, generally zinc oxide
and any inorganic or organic carrier, preferably zinc oxide, silica
and alumina, results in a form of a mixture which is either in a
dough state or paste state, such mixture can be then be shaped,
preferably extruded, to form a particulate, preferably cylindrical
extrudates having a diameter in the range of from about {fraction
(1/32)} inch to 1/2 inch and any suitable length, preferably a
length in the range of from about 1/8 inch to about 1 inch. The
resulting particulates, preferably cylindrical extrudates, are then
dried under a drying condition as disclosed herein and then
calcined under a calcining condition as disclosed herein. Also for
example, when the mix is in the form of a slurry, the particulation
of such slurry is achieved by spray drying the slurry to form
micro-spheres thereof having a size in the range of from about 20
to about 500 microns. Such micro-spheres are then subjected to
drying under a drying condition as disclosed herein and calcining
under a calcining condition as disclosed herein.
[0052] The resulting support component, preferably a particulated,
dried, and calcined support component, generally comprising zinc
oxide and any inorganic or organic carrier, preferably comprising
zinc oxide, silica and alumina, is then incorporated with a
promoter component selected from the group consisting of metals,
metal oxides, and the like and combinations thereof including
compounds containing such metals and metal oxides, preferably a
nickel oxide compound or a nickel oxide precursor or a bimetallic
promoter component comprising a nickel oxide compound, or a nickel
oxide precursor, and a cobalt oxide compound or a cobalt oxide
precursor.
[0053] Following the incorporating of the support component,
preferably a particulated, dried, and calcined support component,
generally comprising zinc oxide and any inorganic or organic
carrier, preferably comprising zinc oxide, silica and alumina, with
a promoter component, the resulting promoted particulates are then
subjected to drying under a drying condition as disclosed herein
and calcined under a calcining condition as disclosed herein to
thereby provide dried, calcined, promoted particulates prior to the
subjecting of such dried, calcined, promoted particulates to
reduction with a reducing agent, preferably hydrogen.
[0054] The promoter component(s) may be incorporated onto the
support component, preferably a particulated, dried, and calcined
support component, generally comprising zinc oxide and any
inorganic or organic carrier, preferably comprising zinc oxide,
silica and alumina, by any suitable means or method(s) for
incorporating the promoter component(s) as a skin onto a substrate
material, such as the dried and calcined particulates, which
results in the formation of a promoted sorbent composition which
can then be dried under a drying condition as disclosed herein and
calcined under a calcining condition as disclosed herein to thereby
provide dried, calcined, promoted particulates. The dried,
calcined, promoted particulates can then be subjected to reduction
with a reducing agent, preferably hydrogen, to thereby provide a
sorbent composition of the present invention.
[0055] A preferred method for incorporating a promoter component as
a skin onto the support component, preferably a particulated,
dried, and calcined support component (i.e., particulates),
generally comprising zinc oxide and any inorganic or organic
carrier, preferably comprising zinc oxide, silica and alumina, is
to impregnate such particulates with a promoter component,
initially in the form of a metal-containing compound, which has
been melted under a melting condition as described herein.
Preferably such promoter component is initially in the form of a
metal-containing compound such as a metal salt, such as, but not
limited to, a metal chloride, a metal nitrate, a metal sulfate, and
the like and combinations thereof (such as, but not limited to,
nickel nitrate hexahydrate). Addition of small amounts of an
aqueous or nonaqueous solvent, such as water, to the promoter
component can be used to assist in the melting of such promoter
component, but such use of a solvent is not required.
[0056] Such melting condition includes a temperature in a range of
from the melting point of the promoter component to below the
decomposition temperature of the promoter component for a time
period and at a pressure that provides for a melted promoter
component. The term "decomposition temperature" refers to the
temperature at which the promoter component is no longer soluble
and is no longer suitable for incorporating, preferably
impregnating, the promoter component as a skin onto the support
component according to the inventive process(es) disclosed
herein.
[0057] The temperature of such melting condition varies depending
on the promoter component but such temperature should be such as to
provide a melted promoter component. Such temperature is generally
in the range of from about 75.degree. F. to about 700.degree. F.,
preferably in the range of from about 85.degree. F. to about
300.degree. F., more preferably in the range of from about
95.degree. F. to about 280.degree. F. and, most preferably, in the
range of from 95.degree. F. to 250.degree. F.
[0058] Such melting condition can include a time period generally
in the range of from about 1 minute to about 2 hours, preferably in
the range of from about 5 minutes to about 1.5 hours and, most
preferably, in the range of from 5 minutes to 1 hour. Such melting
condition can include a pressure generally in the range of from
about atmospheric (i.e., about 14.7 pounds per square inch
absolute) to about 150 pounds per square inch absolute (psia),
preferably in the range of from about atmospheric to about 100
psia, most preferably about atmospheric, so long as the desired
temperature can be maintained.
[0059] The thus-melted promoter component is then used to
incorporate, preferably impregnate, such promoter component as a
skin onto the support component, preferably a particulated, dried
and calcined support component (i.e., particulates), generally
comprising zinc oxide and any inorganic or organic carrier,
preferably comprising zinc oxide, silica and alumina, prepared
according to the process(es) disclosed herein. The melted promoter
component is incorporated, preferably impregnated, onto the support
component, preferably particulates, by any manner or method(s)
which results in substantially all the surface area of the
particulates being contacted with the melted promoter component
resulting in a skin distribution of the promoter component. The
phrase "substantially all the surface area of the particulates
being contacted with the melted promoter component" generally
refers to greater than twenty-five percent of the surface area of
the particulates, preferably greater than forty percent of the
surface area of the particulates, more preferably greater than
sixty percent of the surface area of the particulates, and most
preferably greater than ninety-five percent of the surface area of
the particulates being contacted with the melted promoter
component.
[0060] An example method of incorporating, preferably impregnating,
a melted promoter component as a skin onto the support component,
preferably a particulated, dried and calcined support component
(i.e., particulates), is by mixing a solid promoter component
(i.e., an unmelted promoter component) with the particulates by any
manner or method(s) which results in a mixture of particulates and
solid promoter component. The mixture of particulates and solid
promoter component is then subjected to a melting condition as
described herein, preferably while such mixture is subjected to
constant stirring or tumbling, which results in substantially all
the surface area of the particulates being contacted with a melted
promoter component resulting in a skin distribution of the promoter
component.
[0061] A preferred method of incorporating, preferably
impregnating, a melted promoter component onto the support
component, preferably a particulated, dried and calcined support
component (i.e., particulates), is by pre-heating the particulates
under a heating condition as described herein to thereby provide a
pre-heated support component (i.e., pre-heated particulates)
followed by contact with a solid promoter component (i.e., an
unmelted promoter component) which results in a melting of the
solid promoter component upon contact with the pre-heated
particulates which further results in substantially all the surface
area of the particulates being contacted with the melted promoter
component, i.e., a skin distribution of the promoter component.
Preferably such pre-heated particulates are under constant stirring
or tumbling during contact with the promoter component. Such
mixture of particulates and melted promoter component can be
further heated near the melting point of the promoter component for
a time period in the range of from about 0.5 hour to about 15
hours, preferably in the range of from about 1 hour to about 8
hours and, most preferably, in the range of from 1 hour to 5 hours
to further aid in the melting of the promoter component.
[0062] Such heating condition, suitable for pre-heating the support
component, preferably a particulated, dried and calcined support
component (i.e., particulates), can include a temperature generally
in the range of from about 175.degree. F. to about 300.degree. F.,
preferably in the range of from about 185.degree. F. to about
280.degree. F. and, most preferably, in the range of from
190.degree. F. to 260.degree. F. Such heating condition can include
a time period generally in the range of from about 1 minute to
about 2 hours, preferably in the range of from about 5 minutes to
about 1.5 hours and, most preferably, in the range of from 5
minutes to 1 hour. Such heating condition can include a pressure
generally in the range of from about atmospheric (i.e., about 14.7
pounds per square inch absolute) to about 150 pounds per square
inch absolute (psia), preferably in the range of from about
atmospheric to about 100 psia, most preferably about atmospheric,
so long as the desired temperature can be maintained.
[0063] Another preferred method of incorporating, preferably
impregnating, a melted promoter component onto the support
component, preferably a particulated, dried and calcined support
component (i.e., particulates), is by subjecting a solid promoter
component to a melting condition as described herein to thereby
provide a melted promoter component which has become viscous enough
to pour. The particulates are then contacted with such melted
promoter component by pouring such melted promoter component onto
the surface of the particulates by any manner or method(s) which
results in substantially all the surface area of the particulates
being contacted with the melted promoter component resulting in a
skin distribution of the promoter component. Preferably, such
melted promoter component is poured onto the surface of the
particulates while such particulates are under constant stirring or
tumbling. It can be desirable to pre-heat the support component,
preferably a particulated, dried and calcined support component
(i.e., particulates), under a heating condition as described herein
before contact with the melted promoter component.
[0064] In an example method, solid nickel nitrate hexahydrate is
used to incorporate, preferably impregnate, the nickel of such
solid nickel nitrate hexahydrate as a skin onto the support
component, preferably a particulated, dried and calcined support
component comprising zinc oxide, silica, and alumina (i.e.,
particulates). The nickel of such solid nickel nitrate hexahydrate
is incorporated, preferably impregnated, as a skin onto the
particulates by mixing such solid nickel nitrate hexahydrate with
the particulates by any manner or method(s) which results in a
mixture of solid nickel nitrate hexahydrate and particulates and
then subjecting such mixture, while under constant stirring or
tumbling, to a melting condition as described herein with results
in substantially all the surface area of the particulates being
contacted with melted nickel nitrate hexahydrate resulting in a
skin distribution of the nickel nitrate hexahydrate. In addition,
cobalt nitrate hexahydrate or iron nitrate nonahydrate or manganese
nitrate hexahydrate or copper nitrate or zinc nitrate hexahydrate
or silver nitrate or the like and combinations thereof can be used
in place of nickel nitrate hexahydrate to incorporate, preferably
impregnate, the metal of such metal-containing compound(s) as a
skin onto the particulates in the same above-described manner as
for incorporating, preferably impregnating, the nickel of such
nickel nitrate hexahydrate. Also preferred, solid nickel nitrate
hexahydrate and solid cobalt nitrate hexahydrate are mixed with the
particulates and then the resulting mixture, while under constant
stirring or tumbling, is subjected to a melting condition as
described herein to incorporate, preferably impregnate, the nickel
and cobalt as a skin onto the particulates. After drying and
calcining, a sorbent composition comprising a bimetallic promoter
component comprising nickel and cobalt is formed.
[0065] In a most preferred method, solid nickel nitrate hexahydrate
is used to incorporate, preferably impregnate, the nickel of such
solid nickel nitrate hexahydrate as a skin onto the particulated,
dried and calcined support component comprising zinc oxide, silica,
and alumina (i.e., particulates). The nickel of such solid nickel
nitrate hexahydrate is incorporated, preferably impregnated, as a
skin onto the particulates by contacting such particulates, which
have been pre-heated under a heating condition as described herein,
with the solid nickel nitrate hexahydrate while under constant
stirring or tumbling which results in a melting of the solid nickel
nitrate hexahydrate upon contact with the pre-heated particulates
which results in substantially all the surface area of the
pre-heated particulates being contacted with melted nickel nitrate
hexahydrate resulting in a skin distribution of the nickel nitrate
hexahydrate. In addition, cobalt nitrate hexahydrate or iron
nitrate nonahydrate or manganese nitrate hexahydrate or copper
nitrate or zinc nitrate hexahydrate or silver 33871US2 32 nitrate
or the like and combinations thereof can be used in place of nickel
nitrate hexahydrate to incorporate, preferably impregnate, the
metal of such metal-containing compound(s) as a skin onto the
pre-heated particulates in the same above-described manner as for
incorporating, preferably impregnating, the nickel of such nickel
nitrate hexahydrate. Also, solid nickel nitrate hexahydrate and
solid cobalt nitrate hexahydrate can be contacted with the
pre-heated particulates while under constant stirring or tumbling
to incorporate, preferably impregnate, the nickel and cobalt as a
skin onto the particulates. After drying and calcining, a sorbent
composition comprising a bimetallic promoter component comprising
nickel and cobalt is formed.
[0066] In another most preferred method, solid nickel nitrate
hexahydrate is subjected to a melting condition to thereby provide
a melted nickel nitrate hexahydrate which is viscous enough to
pour. The resulting melted nickel nitrate hexahydrate is then used
to incorporate, preferably impregnate, the nickel of such melted
nickel nitrate hexahydrate as a skin onto the particulated,
calcined support component comprising zinc oxide, silica, and
alumina (i.e., particulates) which have been pre-heated under a
heating condition as described herein. The nickel of such melted
nickel nitrate hexahydrate is incorporated, preferably impregnated
as a skin onto the pre-heated particulates by adding such melted
nickel nitrate hexahydrate to the pre-heated particulates by
pouring such melted nickel nitrate hexahydrate onto the surface of
the pre-heated particulates by any manner or method(s) which
results in substantially all the surface area of the particulates
being contacted with the melted nickel nitrate hexahydrate
resulting in a skin distribution of the nickel nitrate hexahydrate.
Preferably, such melted nickel nitrate hexahydrate is poured onto
the surface of the pre-heated particulates while such particulates
are under constant stirring or tumbling. In addition, cobalt
nitrate hexahydrate or iron nitrate nonahydrate or manganese
nitrate hexahydrate or copper nitrate or zinc nitrate hexahydrate
or silver nitrate or the like and combinations thereof can be used
in place of nickel nitrate hexahydrate to incorporate, preferably
impregnate, the metal of such metal-containing compound(s) as a
skin onto the pre-heated particulates in the same above-described
manner as for incorporating, preferably impregnating, the nickel of
such nickel nitrate hexahydrate. Also, melted nickel nitrate
hexahydrate and melted cobalt nitrate hexahydrate can be poured
onto the surface of the pre-heated particulates while such
particulates are under constant stirring or tumbling. After drying
and calcining, a sorbent composition comprising a bimetallic
promoter component comprising nickel and cobalt is formed.
[0067] Generally, the amount of promoter component, preferably a
melted promoter component, incorporated, preferably impregnated, as
a skin onto the support component, preferably a particulated, dried
and calcined support component comprising zinc oxide, silica, and
alumina prepared according to the process(es) disclosed herein, is
an amount which provides, after the promoted particulate material
has been dried under a drying condition as disclosed herein and
calcined under a calcining condition as disclosed herein, a sorbent
composition having an amount of promoter component as disclosed
herein.
[0068] Generally, a drying condition, as referred to herein, can
include a temperature in the range of from about 180.degree. F. to
about 290.degree. F., preferably in the range of from about
190.degree. F. to about 280.degree. F. and, more preferably, in the
range of from 200.degree. F. to 270.degree. F. Such drying
condition can also include a time period generally in the range of
from about 0.5 hour to about 60 hours, preferably in the range of
from about 1 hour to about 40 hours and, more preferably, in the
range of from 1.5 hours to 20 hours. Such drying condition can also
include a pressure generally in the range of from about atmospheric
(i.e., about 14.7 pounds per square inch absolute) to about 150
pounds per square inch absolute (psia), preferably in the range of
from about atmospheric to about 100 psia, more preferably about
atmospheric, so long as the desired temperature can be maintained.
Any drying method(s) known to one skilled in the art such as, for
example, air drying, heat drying, and the like and combinations
thereof can be used.
[0069] Generally, a calcining condition, as referred to herein, can
include a temperature in the range of from about 400.degree. F. to
about 1800.degree. F., preferably in the range of from about
600.degree. F. to about 1600.degree. F. and, more preferably, in
the range of from 800.degree. F. to about 1500.degree. F. Such
calcining condition can also include a pressure, generally in the
range of from about 7 pounds per square inch absolute (psia) to
about 750 psia, preferably in the range of from about 7 psia to
about 450 psia and, more preferably, in the range of from 7 psia to
150 psia, and a time period generally in the range of from about 1
hour to about 60 hours, preferably for a time period in the range
of from about 2 hours to about 20 hours and, more preferably, for a
time period in the range of from 3 hours to 15 hours.
[0070] Once the promoter component, preferably comprising nickel
resulting from the use of melted nickel nitrate hexahydrate, has
been distributed as a skin onto the support component, preferably a
particulated, dried and calcined support component comprising zinc
oxide, silica, and alumina, the desired reduced-valence promoter
component sorbent, preferably reduced-valence nickel sorbent, is
prepared by drying the resulting composition under a drying
condition as disclosed herein followed by calcining under a
calcining condition as disclosed herein to thereby provide a dried,
calcined, promoted particulate(s). The dried, calcined, promoted
particulates are thereafter subjected to reduction with a suitable
reducing agent, preferably hydrogen, so as to produce a composition
having a skin-distributed reduced-valence promoter component,
preferably a skin-distributed zero-valence promoter component, with
such zero-valence promoter component, preferably zero-valence
nickel, being present in an amount sufficient to permit the removal
of sulfur from a hydrocarbon-containing fluid such as
cracked-gasoline or diesel fuel, according to a process(es)
disclosed herein.
[0071] A sorbent composition having a skin-distributed
reduced-valence promoter component of the present invention is a
composition that has the ability to react chemically and/or
physically with sulfur. It is also preferable that the sorbent
composition removes diolefins and other gum-forming compounds from
cracked-gasoline.
[0072] A sorbent composition having a reduced-valence promoter
component of the present invention comprises a promoter component,
preferably comprising nickel, distributed as a skin that is in a
substantially reduced valence state, preferably a zero valence
state. Preferably, the reduced-valence promoter component is
reduced nickel. The amount of reduced-valence promoter component,
preferably reduced nickel, in a sorbent composition(s) of the
present invention is an amount which will permit the removal of
sulfur from a hydrocarbon-containing fluid such as cracked-gasoline
or diesel fuel. Such amount(s) of reduced-valence promoter
component, preferably reduced nickel, is generally in the range of
from about 5 to about 50 weight percent of the total weight of the
sorbent composition. Preferably the reduced-valence promoter
component, preferably reduced nickel, is present in an amount in
the range of from about 8 to about 40 weight percent of the total
weight of the sorbent composition and, more preferably, in an
amount in the range of from 10 to 30 weight percent of the total
weight of the sorbent composition.
[0073] In one presently preferred embodiment of the present
invention, the reduced nickel is present as a skin in an amount in
the range of from about 10 to 30 weight percent based on the total
weight of the sorbent composition and the reduced nickel has been
substantially reduced to zero valence.
[0074] In another presently preferred embodiment of the present
invention, zinc oxide is present in an amount in the range of from
about 35 to about 50 weight percent zinc oxide based on the total
weight of the sorbent composition, silica is present in an amount
in the range of from about 30 to about 40 weight percent silica
based on the total weight of the sorbent composition, alumina is
present in an amount in the range from about 6 to about 12 weight
percent alumina based on the total weight of the sorbent
composition, and nickel is present, as a skin, prior to reduction
to zero valence in an amount in the range of from about 14 to about
30 weight percent nickel based on the total weight of the sorbent
composition.
[0075] The sorbent composition(s) of the present invention which
are useful in a desulfurization process(es) of the present
invention can be prepared by a process comprising:
[0076] (a) mixing zinc oxide, silica and alumina so as to form a
mixture selected from the group consisting of a wet mix, a dough, a
paste, a slurry and the like and combinations thereof;
[0077] (b) particulating the mixture to form particulates selected
from the group consisting of granules, extrudates, tablets,
pellets, spheres, micro-spheres, and the like and combinations
thereof;
[0078] (c) drying the particulate under a drying condition as
disclosed herein to form a dried particulate;
[0079] (d) calcining the dried particulate under a calcining
condition as disclosed herein to form a calcined particulate;
[0080] (e) incorporating, preferably impregnating, the calcined
particulate with a promoter component, preferably a melted promoter
component, selected from the group consisting of metal, metal
oxides, and the like and combinations thereof to form a promoted
particulate wherein the promoter component is distributed as a skin
on the promoted particulate;
[0081] (f) drying the promoted particulate under a drying condition
as disclosed herein to form a dried, promoted particulate;
[0082] (g) calcining the dried, promoted particulate under a
calcining condition as disclosed herein to form a calcined,
promoted particulate; and
[0083] (h) reducing the calcined, promoted particulate with a
suitable reducing agent so as to produce a sorbent composition
having a skin-distributed reduced-valence promoter component,
preferably a skin-distributed reduced-valence nickel, and wherein
the reduced-valence promoter component is present in an amount
effective for the removal of sulfur from a hydrocarbon-containing
fluid such as cracked-gasoline or diesel fuel when such
hydrocarbon-containing fluid is contacted with a sorbent
composition(s) of the present invention according to a process(es)
of the present invention.
[0084] A process of using a novel sorbent composition(s) of the
present invention to desulfurize a hydrocarbon-containing fluid
comprising cracked-gasoline or diesel fuel to provide a
desulfurized hydrocarbon-containing fluid comprising desulfurized
cracked-gasoline or desulfurized diesel fuel comprises:
[0085] (a) desulfurizing, in a desulfurization zone, a
hydrocarbon-containing fluid with a sorbent composition(s) of the
present invention to thereby provide a desulfurized
hydrocarbon-containing fluid and a resulting sulfurized sorbent
composition;
[0086] (b) separating the desulfurized hydrocarbon-containing fluid
from the resulting sulfurized sorbent composition;
[0087] (c) regenerating, in a regeneration zone, at least a portion
of the sulfurized sorbent composition to thereby provide a
regenerated, desulfurized, sorbent composition;
[0088] (d) reducing, in an activation zone, at least a portion of
the regenerated, desulfurized, sorbent composition to thereby
provide a reduced, regenerated, desulfurized sorbent composition
and;
[0089] (e) returning at least a portion of the reduced,
regenerated, desulfurized sorbent composition to the
desulfurization zone.
[0090] In another embodiment, this invention includes a process for
the removal of sulfur from a hydrocarbon-containing fluid, wherein
said hydrocarbon stream is a combination of cracked gasoline and
diesel fuel. This process comprises, consists of, or consists
essentially of the following:
[0091] (a) contacting the hydrocarbon-containing fluid with a
composition comprising a zinc oxide, a silica containing material,
an aluminum containing material selected from the group consisting
of alumina, aluminate, and combinations thereof, and a promoter
wherein at least a portion of the promoter is present as the
reduced valence promoter and in an amount which will effect the
removal of sulfur from the hydrocarbon-containing fluid in a
desulfurization zone under conditions such that there is formed a
desulfurized hydrocarbon-containing fluid and a sulfurized
composition;
[0092] (b) separating the desulfurized hydrocarbon-containing fluid
from the sulfurized composition thereby forming a separator
desulfurized hydrocarbon-containing fluid and a separated
sulfurized composition;
[0093] (c) regenerating at least a portion of the separated
sulfurized composition in a regeneration zone so as to remove at
least a portion of the sulfur contained therein and/or thereon,
thereby forming a regenerated composition;
[0094] (d) reducing said regenerated composition in an activation
zone so as to provide a reduced composition having a reduced
valence promoter content therein which will effect the removal of
sulfur from a hydrocarbon-containing fluid when contacted with
same; and thereafter
[0095] (e) returning at least a portion of the reduced composition
to the desulfurization zone.
[0096] In this embodiment, the hydrocarbon containing fluid can
comprise, consist of, or consist essentially of a combination of
cracked gasoline and diesel fuel. Preferably, the diesel fuel is
light cycle oil.
[0097] The desulfurizing step (a) of the present invention is
carried out under a set of conditions that includes total pressure,
temperature, weight hourly space velocity and hydrogen flow. These
conditions are such that the sorbent composition can desulfurize
the hydrocarbon-containing fluid to produce a desulfurized
hydrocarbon-containing fluid and a sulfurized sorbent
composition.
[0098] In carrying out the desulfurization step of a process of the
present invention, it is preferred that the hydrocarbon-containing
fluid, be in a gas or vapor phase. However, in the practice of the
present invention it is not essential that the
hydrocarbon-containing fluid be totally in a gas or vapor
phase.
[0099] The total pressure can be in the range of from about 15
pounds per square inch absolute (psia) to about 1500 psia. However,
it is presently preferred that the total pressure be in a range of
from about 50 psia to about 500 psia.
[0100] In general, the temperature should be sufficient to keep the
hydrocarbon-containing fluid in essentially a vapor or gas phase.
While such temperatures can be in the range of from about
100.degree. F. to about 1000.degree. F., it is presently preferred
that the temperature be in the range of from about 400.degree. F.
to about 850.degree. F. when treating a cracked-gasoline and in the
range of from about 500.degree. F. to about 900.degree. F. when
treating a diesel fuel including light cycle oil. Preferably, the
temperature is in the range of from about 400.degree. F. to about
900.degree. F. when treating a cracked gasoline/diesel fuel
combination.
[0101] Weight hourly space velocity (WHSV) is defined as the
numerical ratio of the rate at which a hydrocarbon-containing fluid
is charged to the desulfurization zone in pounds per hour divided
by the pounds of sorbent composition contained in the
desulfurization zone to which the hydrocarbon-containing fluid is
charged. In the practice of the present invention, such WHSV should
be in the range of from about 0.5 to about 50 hr.sup.-1, preferably
in the range of from about 1 to about 20 hr.sup.-1. The
desulfurizing, also referred to as desulfurization, should be
conducted for a time sufficient to effect the removal of sulfur
from such hydrocarbon-containing fluid.
[0102] In carrying out the desulfurizing step, it is presently
preferred that an agent be employed which interferes with any
possible chemical or physical reacting of the olefinic and aromatic
compounds in the hydrocarbon-containing fluid which is being
treated with the sorbent composition. Preferably, such agent is
hydrogen.
[0103] Hydrogen flow in the desulfurization zone is generally such
that the mole ratio of hydrogen to hydrocarbon-containing fluid is
the range of from about 0.1 to about 10, preferably in the range of
from about 0.2 to about 3.
[0104] The desulfurization zone can be any zone wherein
desulfurization of a hydrocarbon-containing fluid such as
cracked-gasoline, diesel fuel, a gasoline/distillate combination,
or the like, can take place. The regeneration zone can be any zone
wherein desulfurizing or regeneration of a sulfurized sorbent
composition can take place. The activation zone can be any zone
wherein activation, i.e., reduction, of a regenerated, desulfurized
sorbent composition can take place. Examples of suitable zones are
fixed bed reactors, moving bed reactors, fluidized bed reactors,
transport reactors, reactor vessels and the like.
[0105] If desired, during the desulfurization of a
hydrocarbon-containing fluid(s) according to a process(es)
disclosed herein, diluents such as methane, carbon dioxide, flue
gas, nitrogen and the like and combinations thereof can be used.
Thus, it is not essential to the practice of a process(es) of the
present invention that a high purity hydrogen be employed in
achieving the desired desulfurization of a hydrocarbon-containing
fluid such as cracked-gasoline and/or diesel fuel.
[0106] It is presently preferred when utilizing a fluidized bed
reactor system that a sorbent composition be used having a
particulate size in the range of from about 20 to about 1000
micrometers. Preferably, such sorbent composition should have a
particulate size in the range of from about 40 to about 500
micrometers. When a fixed bed reactor system is employed for the
practice of a desulfurization process(es) of the present invention,
the sorbent composition should generally have a particulate size in
the range of from about {fraction (1/32)} inch to about 1/2 inch
diameter, preferably in the range of from about {fraction (1/32)}
inch to about 1/4 inch diameter.
[0107] It is further presently preferred to use a sorbent
composition having a surface area in the range of from about 1
square meter per gram (m.sup.2/g) to about 1000 square meters per
gram of sorbent composition, preferably in the range of from about
1 m.sup.2/g to about 800 m.sup.2/g.
[0108] The separation of the desulfurized hydrocarbon-containing
fluid, preferably gaseous or vaporized desulfurized
hydrocarbon-containing fluid, and sulfurized sorbent composition
can be accomplished by any manner or method(s) known in the art
that can separate a solid from a gas. Examples of such means are
cyclonic devices, settling chambers, impingement devices for
separating solids and gases, and the like and combinations thereof.
The desulfurized hydrocarbon-containing fluid, preferably
desulfurized gaseous cracked-gasoline or desulfurized gaseous
diesel fuel, can then be recovered and preferably liquefied.
Liquification of such desulfurized hydrocarbon-containing fluid can
be accomplished by any manner or method(s) known in the art.
[0109] The hydrocarbon-containing fluid as described herein,
preferably gaseous cracked-gasoline or gaseous diesel fuel, or a
gasoline/distillate combination, suitable as a feed in a
process(es) of the present invention is a composition that
comprises olefins, aromatics, sulfur, as well as paraffins and
naphthenes.
[0110] The amount of olefins in gaseous cracked-gasoline is
generally in the range of from about 10 to about 35 weight percent
olefins based on the total weight of the gaseous cracked-gasoline.
For diesel fuel there is essentially no olefin content.
[0111] The amount of aromatics in gaseous cracked-gasoline is
generally in the range of from about 20 to about 40 weight percent
aromatics based on the total weight of the gaseous
cracked-gasoline. The amount of aromatics in gaseous diesel fuel is
generally in the range of from about 10 to about 90 weight percent
aromatics based on the total weight of the gaseous diesel fuel.
[0112] The amount of sulfur in the hydrocarbon-containing fluid,
preferably cracked-gasoline or diesel fuel, or a
gasoline/distillate combination, suitable for use in a process(es)
of the present invention can be in the range of from about less
than 10 parts per million sulfur by weight of the cracked-gasoline
to about 10,000 parts per million sulfur by weight of the
cracked-gasoline and from about 100 parts per million sulfur by
weight of the diesel fuel to about 50,000 parts per million sulfur
by weight of the diesel fuel prior to the treatment of such
hydrocarbon-containing fluid(s) with a desulfurization process(es)
of the present invention.
[0113] The amount of sulfur in the desulfurized
hydrocarbon-containing fluid, such as desulfurized cracked-gasoline
or desulfurized diesel fuel, or a desulfurized gasoline/distillate
combination, following treatment in accordance with a
desulfurization process(es) of the present invention is less than
about 100 parts per million (ppm) sulfur by weight of
hydrocarbon-containing fluid, preferably less than about 90 ppm
sulfur by weight of hydrocarbon-containing fluid, and more
preferably less than about 80 ppm sulfur by weight of
hydrocarbon-containing fluid.
[0114] In carrying out a process(es) of the present invention, if
desired, a stripper zone can be inserted before and/or after the
regeneration of the sulfurized sorbent composition. Such stripper
zone, preferably utilizing a stripping agent, will serve to remove
a portion, preferably all, of any hydrocarbon(s) from the
sulfurized sorbent composition. Such stripper zone can also serve
to remove oxygen and sulfur dioxide from the system prior to
introduction of the regenerated sorbent composition into the
activation zone. Such stripping employs a set of conditions that
includes total pressure, temperature, and stripping agent partial
pressure.
[0115] Preferably, the stripping, when employed, is carried out at
a total pressure in the range of from about 25 pounds per square
inch absolute (psia) to about 500 psia. The temperature for such
stripping can be in the range of from about 100.degree. F. to about
1000.degree. F. Such stripping is carried out for a time sufficient
to achieve the desired level of stripping. Such stripping can
generally be achieved in a time period in the range of from about
0.1 hour to about 4 hours, preferably in the range of from about
0.3 hour to about 1 hour.
[0116] The stripping agent is a composition(s) that helps to remove
a hydrocarbon(s) from the sulfurized sorbent composition.
Preferably, the stripping agent is nitrogen.
[0117] The regeneration is carried out at a set of conditions that
includes total pressure and sulfur removing agent partial pressure.
Total pressure is generally in the range of from about 10 pounds
per square inch absolute (psia) to about 500 psia.
[0118] The sulfur removing agent partial pressure is generally in
the range of from about 1 percent to about 100 percent of the total
pressure.
[0119] The sulfur removing agent is a composition that helps to
generate gaseous sulfur-containing compounds and oxygen-containing
compounds such as sulfur dioxide, as well as to burn off any
remaining hydrocarbon deposits that might be present. The preferred
sulfur removing agent suitable for use in the sorbent regeneration
zone is oxygen or an oxygen-containing gas(es) such as air. Such
regeneration is carried out for a time sufficient to achieve the
desired level of regeneration. Such regeneration can generally be
achieved in a time period in the range of from about 0.1 hour to
about 24 hours, preferably in the range of from about 0.5 hour to
about 3 hours.
[0120] The regeneration is carried out at a temperature generally
in the range of from about 100.degree. F. to about 1500.degree. F.,
preferably in the range of from about 800.degree. F. to about
1200.degree. F.
[0121] The desulfurized sorbent composition is then reduced in an
activation zone with a reducing agent, preferably hydrogen, so that
at least a portion of the promoter component, preferably comprising
nickel, which also can be distributed as a skin on the sorbent
composition is reduced to thereby provide a sorbent composition
having a reduced-valence promoter component, preferably reduced
nickel. Such sorbent composition has a reduced-valence promoter
component, preferably reduced nickel, which also can be distributed
as a skin on such sorbent composition in an amount that provides
for the removal of sulfur from a hydrocarbon-containing fluid such
as cracked-gasoline or diesel fuel according to the inventive
process(es) disclosed herein.
[0122] In general, when practicing a process(es) of the present
invention, the activation, i.e., reduction, of the regenerated,
desulfurized sorbent composition is carried out at a temperature in
the range of from about 100.degree. F. to about 1500.degree. F. and
at a pressure in the range of from about 15 pounds per square inch
absolute (psia) to about 1500 psia. Such reduction is carried out
for a time sufficient to achieve the desired level of promoter
component reduction. Such reduction can generally be achieved in a
time period in the range of from about 0.01 hour to about 20
hours.
[0123] Following the activation, i.e., reduction, of the
regenerated, desulfurized sorbent composition, at least a portion
of the resulting activated (i.e., reduced) sorbent composition can
be returned to the desulfurization zone.
[0124] When carrying out a process(es) of the present invention,
the steps of desulfurization, regeneration, activation (i.e.,
reduction), and optionally stripping before and/or after such
regeneration, can be accomplished in a single zone or vessel or in
multiple zones or vessels.
[0125] When carrying out a process(es) of the present invention in
a fixed bed reactor system, the steps of desulfurization,
regeneration, activation, and optionally stripping before and/or
after such regeneration, are accomplished in a single zone or
vessel.
[0126] When a desulfurized hydrocarbon-containing fluid resulting
from the practice of the present invention is a desulfurized diesel
fuel, such desulfurized diesel fuel can be used in the formulation
of diesel fuel blends to provide diesel fuel products suitable for
commercial consumption and can also be used where a diesel fuel
containing low levels of sulfur is desired.
[0127] The following examples are presented to further illustrate
this invention and are not to be construed as unduly limiting the
scope of this invention.
EXAMPLE I
[0128] Base Sorbent Material
[0129] A 20.02 pound quantity of diatomite silica was mixed with a
23.65 pound quantity of Nyacol AL-20 alumina solution in a
mix-Muller. Such alumina solution was added to the mix-Muller over
a period of about 15 minutes. While mixing, a 25.03 pound quantity
of dry zinc oxide powder was then added to the above mixture and
further mixed for about 30 minutes to form an extrudable paste.
Such extrudable paste was then extruded through a laboratory 2-inch
Bonnot extruder employing a 3/8-inch thick die containing 1/8-inch
holes. The wet extrudate was then dried at 300.degree. F. overnight
(i.e., about 16 hours) and then calcined at 1175.degree. F. for 1
hour to thereby provide a base sorbent material. A representative
sample of the base sorbent material consisted of particulates with
each particulate having a length of about 1/8 inch to about 1/4
inch and a diameter of about 1/8 inch.
[0130] Control Sorbent A
[0131] A 25 pound quantity of the above-described particulated base
sorbent material was impregnated with a solution of 13.62 pounds of
nickel nitrate hexahydrate (Ni(NO.sub.3).sub.2.6H.sub.2O) dissolved
in 2.18 pounds of deionized water in the following manner. The
nickel nitrate hexahydrate solution was heated on a hot plate to
aid in the dissolving of the nickel nitrate hexahydrate. The
impregnation of the particulated base sorbent material was then
conducted using a spray impregnation technique which consisted of
utilizing an ultrasonic spray nozzle to spray the nickel solution
onto the particulated base sorbent material while the particulated
base sorbent material was being tumbled in a rotary coater. The
resulting material was then dried at 300.degree. F. overnight
(i.e., about 16 hours) and then calcined at 1175.degree. F. for 1
hour to thereby provide a nickel-containing spray impregnated
particulated material containing about 11 weight percent nickel
based on the total weight of the material. A 453.6 gram quantity of
such nickel-containing spray impregnated particulated material was
then impregnated with a solution of 157.22 grams of nickel nitrate
hexahydrate and 31.8 grams of deionized water using a spray
impregnation technique utilizing an ultrasonic spray nozzle.
[0132] The resulting twice nickel impregnated particulated material
was then placed in an oven and dried at a temperature of
302.degree. F. for 1 hour. The temperature was then increased to
1175.degree. F. and maintained at 1175.degree. F. for 1 hour to
thereby obtain a 490 gram quantity of twice nickel impregnated
particulated material containing about 18 weight percent nickel
based on the total weight of the material.
[0133] Such twice nickel impregnated particulated material was then
impregnated with a solution of 89.8 grams of nickel nitrate
hexahydrate and 25 grams of deionized water. The impregnation was
conducted using a spray impregnation technique utilizing an
ultrasonic spray nozzle. The resulting material was then placed in
an oven and dried at 302.degree. F. for 1 hour. The temperature was
then increased to 1175.degree. F. and then maintained at
1175.degree. F. for 1 hour to thereby provide Control Sorbent A.
Control Sorbent A contained about 22 weight percent nickel based on
the total weight of the material.
[0134] Scanning Electron Microprobe (SEM) analysis of three
representative sample particulates of Control Sorbent A revealed
that the zinc and nickel were uniformly distributed throughout each
particulate.
[0135] Invention Sorbent B
[0136] A mixture of melted nickel nitrate hexahydrate
(Ni(NO.sub.3).sub.2.6H.sub.2O) and water was prepared by mixing
13.61 pounds of nickel nitrate hexahydrate and 1.7 pounds of
deionized water and heating such mixture in an oven at 200.degree.
F. for about 1 hour until the nickel nitrate hexahydrate melted to
a point that the mixture of melted nickel nitrate hexahydrate and
deionized water became viscous enough to pour. A 25 pound quantity
of the above-described particulated base sorbent material was then
heated at 250.degree. F. for about 1 hour in an oven and then
placed in a rotary coater. The mixture of melted nickel nitrate
hexahydrate and water was then contacted with the surface of the
heated particulated base sorbent material in the rotary coater by
pumping the mixture of melted nickel nitrate hexahydrate and water
through a plastic tubing, having a diameter of about 1/4 inch, onto
the surface of the heated particulated base sorbent material. It
was observed that the nickel did not absorb into the material, but
crystallized on the surface. The resulting material was then dried
at 250.degree. F. for 1 hour and then calcined at 1175.degree. F.
for 1 hour. Invention Sorbent B contained about 11 weight percent
nickel based on the total weight of Invention Sorbent B.
[0137] Scanning Electron Microprobe (SEM) analysis of three
representative sample particulates of Invention Sorbent B revealed
that the zinc was uniformly distributed throughout the particulate
whereas the nickel was concentrated as a skin near the surface of
the particulate (particulate 1: essentially all nickel concentrated
within 600 micrometers of the surface; particulate 2: essentially
all nickel concentrated within 200 micrometers of the surface; and
particulate 3: essentially all nickel concentrated within 200
micrometers of the surface).
[0138] Invention Sorbent C
[0139] A 226.8 gram quantity of the above-described particulated
base sorbent material was heated at 250.degree. F. for about 1 hour
in an oven. The thus-heated particulated base sorbent material was
then placed in a 1000 mL beaker in a heat mantel where the heat was
maintained at approximately 250.degree. F. A 123.5 gram quantity of
powdered nickel nitrate hexahydrate (Ni(NO.sub.3).sub.2.6H.sub.2O),
sized 250 to 300 mesh, was then slowly added to the heated
particulated base sorbent material under stirring to thereby
contact the heated particulated base sorbent material with the
powdered nickel nitrate hexahydrate. Towards the end of the nickel
nitrate hexahydrate addition, a heat gun was used to dry any excess
moisture off of the material. The resulting material was then
placed in an oven and dried at 302.degree. F. for about 1 hour. The
temperature was then increased to 1175.degree. F. and maintained at
1175.degree. F. for a period of 1 hour to thereby provide Invention
Sorbent C. Invention Sorbent C contained about 11 weight percent
nickel based on the total weight of Invention Sorbent C.
[0140] Scanning Electron Microprobe (SEM) analysis of three
representative sample particulates of Invention Sorbent C revealed
that the zinc was uniformly distributed throughout the particulates
whereas the nickel was concentrated as a skin near the surface of
the particulates (particulate 1: essentially all nickel
concentrated within 250 micrometers of the surface; particulate 2:
essentially all nickel concentrated within 200 micrometers of the
surface; and particulate 3: essentially all nickel concentrated
within 375 micrometers of the surface).
EXAMPLE II
[0141] This example illustrates the performance of Control Sorbent
A and Invention Sorbent B described herein in Example I in a
desulfurization process.
[0142] Ten grams of Control Sorbent A were placed in a 1/2-inch
diameter stainless steel tube having a length of about 12 inches.
The bottom of the tube was packed with alundum pellets (obtained
from Norton Chemical under the designation R-268) to provide a
inert support for the bed of sorbent which was placed in the middle
of the tube. Alundum was also placed on top of the sorbent bed.
[0143] During each cycle, gaseous cracked-gasoline was pumped
downwardly through the reactor at a rate of 13.4 milliliters per
hour (mL/hr). The gaseous cracked-gasoline had a motor octane
number (MON) of 80, an olefin content of 24.9 weight percent, 340
parts per million sulfur by weight sulfur-containing compounds
based on the total weight of the gaseous cracked-gasoline, and
about 95 weight percent thiophenic compounds (such as, for example,
alkyl benzothiophenes, alkyl thiophenes, benzothiophenes and
thiophenes) based on the weight of sulfur-containing compounds in
the gaseous cracked-gasoline.
[0144] During each cycle, the reactor was maintained at a
temperature of 700.degree. F. and a pressure of 15 pounds per
square inch absolute (psia). Hydrogen flow was at 150 standard
cubic centimeters per minute (sccm) diluted with 150 sccm of
nitrogen.
[0145] Before Cycle 1 was initiated, Control Sorbent A was reduced
with hydrogen flowing at a rate of 300 sccm at a temperature of
700.degree. F. for a period of one hour. Each cycle consisted of
four hours with the product sulfur (ppm) for each cycle being
measured at one hour intervals over each four-hour cycle period.
After each cycle, Control Sorbent A was regenerated at 900.degree.
F. for one hour with a mixture of oxygen and nitrogen containing
four volume percent oxygen (i.e., regeneration), then purged with
nitrogen, and then reduced in hydrogen flowing at a rate of 300
sccm for one hour at 700.degree. F. (i.e., activation). Control
Sorbent A was tested over four cycles.
[0146] The above-described testing procedure was then repeated in
the same manner with the exception that Invention Sorbent B was
used in place of Control Sorbent A. Also, Invention Sorbent B was
tested over a period of three cycles instead of four.
[0147] The results of the test are shown below in Table I.
1 TABLE I Control Sorbent A Invention Sorbent B (11% (22% Nickel;
Uniform Distribution) Nickel; Skin Distribution) Cycle 1 Cycle 2
Cycle 3 Cycle 4 Cycle 1 Cycle 2 Cycle 3 SULFUR (ppm) IN THE SULFUR
(ppm) IN THE TOS.sup.1 PRODUCT PRODUCT 1 hr 40 20 25 45 5 15 10 2
hr 30 30 40 45 5 20 20 3 hr 30 35 45 50 5 20 20 4 hr 30 35 45 50 5
30 25 .sup.1TOS denotes Time on Stream in hours
[0148] Test data in Table I clearly demonstrate that use of a
sorbent composition of the present invention to remove sulfur from
cracked-gasoline containing 340 parts per million sulfur by weight
sulfur-containing compounds based on the total weight of the
cracked-gasoline results in a significant reduction of the sulfur
content of such cracked-gasoline, generally to a level of about 5
to 30 parts per million sulfur.
[0149] The test data in Table I further demonstrate that a sorbent
composition containing 11 weight percent nickel distributed as a
skin on the sorbent composition prepared according to a process of
the present invention which utilized a melting technique and very
little water desulfurized the cracked-gasoline significantly better
than a sorbent composition containing twice as much nickel (22
weight percent) prepared using a spray impregnation technique which
utilized a substantial quantity of water.
Example III
[0150] One hundred twenty-five grams of a gelled base component
comprising zinc oxide, expanded perlite, and alumina were
impregnated with nickel nitrate hexahydrate melted in water. This
process yielded 150 mL of a composition with 18 weight percent
nickel.
[0151] Thirty grams of this composition were diluted with alundum
to yield about 200 mL of solution. The solution was then placed in
a 1 inch diameter stainless steel reactor to a yield bed of
approximately 11 inches.
[0152] The composition was reduced with hydrogen flowing at a rate
2 standard cubic feet per hour (scfh) near atmospheric pressure. At
the start of the reduction period, the bed temperature was
approximately 880.degree. F. The temperature was ramped down to
725.degree. F. over a one-hour period and then held steady for
about two hours.
[0153] A feed mixture was prepared by blending cracked gasoline
with light cycle oil in a ratio of 4:1 by volume. The sulfur
content of the feed mixture was 920 ppm by weight and the research
octane number (RON) and cetane number were 92.63 and 22.6,
respectively.
[0154] During each reaction experiment, the reactor was maintained
at a temperature of 780.degree. F. and a pressure of 150 pounds per
square inch gauge (psig). Hydrogen and the feed mixture were pumped
downwardly through the reactor, where the mixture completely
vaporized. The liquid feed rate was 100 ml per hour and the
hydrogen flow rate was 0.318 scfh. The experiment lasted twelve
hours.
[0155] At the end of the reaction experiment, the bed temperature
was raised to about 900.degree. F. where the composition was
regenerated initially under 0.48 scfh air and 1 scfh nitrogen for
about one hour and then under 1 scfh air and 1 scfh nitrogen for an
additional half hour. The temperature was then decreased to
780.degree. F. and the sample purged with nitrogen.
[0156] For analysis of the properties of the feed and product, the
feed mixture and the product were separately fractionated into
their gasoline and light cyclone oil components in an Oldershaw
column. The liquid below the cut point of 380.degree. F. was termed
gasoline and the liquid above was termed light cycle oil. The
properties of the liquids were determined by standard analytical
procedures, except the change in octane, which was estimated using
a correlation based on the concentrations of olefins in the feed
and the product. The results are shown in Table II, III, and
IV.
2TABLE II Product Properties Property Value Total Sulfur 225 ppm
Hydrogen 12.07 wt % Bromine Number 32.5
[0157]
3TABLE III Gasoline Fraction Properties Feed Product Change Sulfur
(ppm) 123 5 96% RON 92.63 91.11 -1.52 MON 80.4 80.43 0.03 (RON +
MON)/2 86.52 85.77 -0.745
[0158]
4TABLE IV Light Cycle Oil Fraction Properties Feed Product Change
Sulfur (ppm) 2100 520 75% Hydrogen Content (wt %) 10.75 10.74 .01
Density (kg/m.sup.3) 890 888 2
Example IV
[0159] The same reactor and bed mixture described in the previous
Example were again operated in the same manner, with the same feed
mixture, except that the flow rate of liquid feed was increased to
150 ml per hour, the flow rate of hydrogen was increased to 0.468
scfh and the bed temperature was raised to 800.degree. F.
[0160] Following the reaction experiment, the bed was regenerated
as in the previous Example. Likewise, the feed mixture and product
were fractionated as in the previous Example. The results are shown
in Tables V, VI and VII.
5TABLE V Product Properties Property Value Total Sulfur 320 ppm
Hydrogen 11.99 wt % Bromine Number 34.4
[0161]
6TABLE VI Gasoline Fraction Properties Feed Product Change Sulfur
(ppm) 122.8 11 91% RON 92.63 91.66 -0.97 MON 80.4 80.6 0.2 (RON +
MON)/2 86.52 86.13 -0.385
[0162]
7TABLE VII Light Cycle Oil Fraction Properties Feed Product Change
Sulfur (ppm) 2100 710 66% Hydrogen Content (wt %) 10.75 10.74 -.01
Density (Kg/m.sup.3) 890 888 2
[0163] The results shown in the above examples clearly demonstrate
that the present invention is well adapted to carry out the objects
and attain the ends and advantages mentioned as well as those
inherent therein.
[0164] Reasonable variations, modifications, and adaptions can be
made within the scope of the disclosure and the appended claims
without departing from the scope of this invention.
* * * * *