U.S. patent application number 16/285764 was filed with the patent office on 2019-08-29 for metal nanoparticle-deposited, nitrogen-doped carbon adsorbents for removal of sulfur impurities in fuels.
The applicant listed for this patent is Chevron U.S.A. Inc., Triad National Security, LLC. Invention is credited to Hoon Taek CHUNG, Zunqing HE, Piotr ZELENAY, Bi-Zeng ZHAN.
Application Number | 20190262798 16/285764 |
Document ID | / |
Family ID | 67685022 |
Filed Date | 2019-08-29 |
United States Patent
Application |
20190262798 |
Kind Code |
A1 |
ZHAN; Bi-Zeng ; et
al. |
August 29, 2019 |
METAL NANOPARTICLE-DEPOSITED, NITROGEN-DOPED CARBON ADSORBENTS FOR
REMOVAL OF SULFUR IMPURITIES IN FUELS
Abstract
Metal nanoparticle-deposited, nitrogen-doped carbon adsorbents
are disclosed, along with methods of removing sulfur compounds from
a hydrocarbon feed stream using these adsorbents.
Inventors: |
ZHAN; Bi-Zeng; (Albany,
CA) ; HE; Zunqing; (San Rafael, CA) ; CHUNG;
Hoon Taek; (Los Alamos, NM) ; ZELENAY; Piotr;
(Los Alamos, NM) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Chevron U.S.A. Inc.
Triad National Security, LLC |
San Ramon
Los Alamos |
CA
NM |
US
US |
|
|
Family ID: |
67685022 |
Appl. No.: |
16/285764 |
Filed: |
February 26, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62635482 |
Feb 26, 2018 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B01J 20/3204 20130101;
B01J 20/28007 20130101; C10G 2300/1025 20130101; C10G 2300/207
20130101; C10G 2300/202 20130101; B01J 20/0233 20130101; B01J 20/20
20130101; C10G 2300/1051 20130101; B01J 20/3078 20130101; C10G
2300/1055 20130101; B01J 20/3236 20130101; C10G 2300/80 20130101;
B01J 20/3295 20130101; C10G 25/003 20130101 |
International
Class: |
B01J 20/20 20060101
B01J020/20; B01J 20/02 20060101 B01J020/02; B01J 20/28 20060101
B01J020/28; B01J 20/30 20060101 B01J020/30; B01J 20/32 20060101
B01J020/32; C10G 25/00 20060101 C10G025/00 |
Claims
1. A metal nanoparticle-deposited, nitrogen-doped carbon adsorbent,
produced by a process comprising: a) contacting at least one
nitrogen precursor and a suitable first metal-containing salt in a
first strong acid solution; b) contacting a product of a) and an
oxidant; c) heating a product of b) in an inert atmosphere; d)
contacting a product of c) with a second strong acid solution; e)
heating a product of d) in an inert atmosphere, and f) contacting
the product of e) with a second metal-containing salt; thereby
producing the metal nanoparticle-deposited, nitrogen-doped carbon
adsorbent.
2. The adsorbent of claim 1, wherein the second metal-containing
salt is a gold-containing salt, and the metal
nanoparticle-deposited, nitrogen-doped carbon adsorbent is a gold
nanoparticle-deposited, nitrogen-doped carbon adsorbent.
3. The adsorbent of claim 1, wherein said a) is contacting two
nitrogen precursors and the suitable first metal-containing salt in
a first strong acid solution.
4. The adsorbent of claim 3, wherein said two nitrogen precursors
are a first nitrogen precursor which is aniline and a second
nitrogen precursor which is cyanimide.
5. The adsorbent of claim 1, wherein said b) is contacting the
product of a) and (NH.sub.4).sub.2S.sub.2O.sub.8, thus forming an
oxidized product, and contacting said oxidized product with an
aqueous solution containing carbon black and a low molecular weight
alcohol.
6. The adsorbent of claim 1, wherein said c) is heating the product
of b) to a first temperature of from about 35.degree. C. to about
100.degree. C., and then to a second temperature of from about
500.degree. C. to about 1000.degree. C.
7. The adsorbent of claim 1, wherein said d) is contacting the
product of c) with either an H.sub.2SO.sub.4 solution or a
HNO.sub.3 solution.
8. The adsorbent of claim 1, wherein said e) is heating the product
of d) from about 500.degree. C. to about 1000.degree. C.
9. The absorbent of claim 1, wherein f) does not comprise a
reducing agent.
10. The absorbent of claim 1, wherein f) comprises a reducing
agent.
11. A method for removing sulfur compounds from a hydrocarbon feed
stream comprising: A) providing a first hydrocarbon feed stream,
which is contaminated with the sulfur compounds; and B) passing the
first hydrocarbon feed stream through a desulfurization system
comprising the metal nanoparticle-deposited, nitrogen-doped carbon
adsorbent, to produce a second hydrocarbon feed stream which has
about 30% to about 99.9% by weight less of the sulfur compounds
than the first hydrocarbon feed stream, wherein the metal
nano-particle-deposited, nitrogen-doped carbon absorbent is
produced by a process comprising: a) contacting at least one
nitrogen precursor and a suitable first metal-containing salt in a
first strong acid solution; b) contacting a product of a) and an
oxidant; c) heating a product of b) in an inert atmosphere; d)
contacting a product of c) with a second strong acid solution; e)
heating a product of d) in an inert atmosphere, and f) contacting
the product of e) with a second metal-containing salt.
12. The method of claim 11, wherein the hydrocarbon feed stream is
a liquid hydrocarbon feed stream.
13. The method of claim 12, wherein the liquid hydrocarbon feed
stream is selected from the group consisting of diesel fuel, jet
fuel, gasoline, kerosene, compressed natural gas, and liquefied
petroleum gas (LPG).
14. The method of claim 11, wherein the sulfur compounds comprise
dibenzothiophene (DBT).
15. The method of claim 11, wherein the sulfur compounds comprise
4,6-dimethyldibenzothiophene (DMDBT).
16. A method of making a metal nanoparticle-deposited,
nitrogen-doped carbon adsorbent, the method comprising: a)
contacting at least one nitrogen precursor and a suitable first
metal-containing salt in a first strong acid solution; b)
contacting a product of a) and an oxidant; c) heating a product of
b) in an inert atmosphere; d) contacting a product of c) with a
second strong acid solution; e) heating a product of d) in an inert
atmosphere, and f) contacting the product of e) with a second
metal-containing salt.
17. The method of claim 16, wherein the second metal-containing
salt is a gold-containing salt, and the metal
nanoparticle-deposited, nitrogen-doped carbon adsorbent is a gold
nanoparticle-deposited, nitrogen-doped carbon adsorbent.
18. The method of claim 16, wherein said c) is heating the product
of b) to a first temperature of from about 35.degree. C. to about
100.degree. C., and then to a second temperature of from about
500.degree. C. to about 1000.degree. C.
19. The method of claim 16, wherein said e) is heating the product
of d) from about 500.degree. C. to about 1000.degree. C.
20. The method of claim 16, wherein f) does not comprise a reducing
agent.
Description
RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional
Application No. 62/635,482, filed on Feb. 26, 2018, and
incorporated herein by reference.
TECHNICAL FIELD
[0002] The invention relates to a novel adsorbent and method for
removing sulfur compounds from hydrocarbon feed streams,
particularly for removing sulfur compounds from liquid fuels. In
one embodiment, the invention relates to the removal of thiophene
and thiophene derivatives from liquid fuels including diesel and
jet fuel.
BACKGROUND
[0003] One of the major challenges facing petroleum refiners today
is the ultra-deep desulfurization of diesel, which requires that
sulfur levels be reduced to less than 10 ppm. While the
concentrations of thiophenes and, to a lesser extent,
benzothiophenes can be reduced to the required levels by catalytic
hydrodesulfurization, in which the organic sulfur species are
converted to H.sub.2S and the corresponding hydrocarbon, removal of
sulfur from 4,6-dialkyl dibenzothiophenes to a similar extent is
extremely difficult in part because the alkyl groups inhibit access
to the sulfur atom. A further complication is that the hydrogen
demand for removing sulfur from dialkyl dibenzothiophenes is
greater than that from other sulfur-containing molecules because
one of the benzene rings must first undergo hydrogenation before
desulfurization can occur. Furthermore, at the high hydrogen
pressures required for desulfurization of dialkyl
dibenzothiophenes, some of the aromatic compounds present in diesel
also undergo hydrogenation, further raising the overall hydrogen
required for ultra-deep desulfurization.
[0004] A possible alternative to hydrodesulfurization is selective
adsorption of thiophene derivatives on a solid adsorbent. The most
promising of materials that have been explored to date are based on
cation-exchanged zeolites and metals, metal halides, other metal
salts supported on activated carbon (AC). Metal cations such as
Na.sup.+, K.sup.+, Ag.sup.+, Ni.sup.2+, Cu.sup.2+, Zn.sup.2+,
Pd.sup.2+, Fe.sup.3+, Ce.sup.3+ have been considered as adsorption
centers. Adsorbents based on activated carbon have generally been
found to exhibit higher adsorption capacities than those based on
zeolites, and it has been reported that the adsorption capacity for
benzothiophene and dibenzothiophene follows the order
Ag/AC>Ni.sup.2+/AC>Cu.sup.2+/AC>Zn.sup.2+/AC>AC>-
Fe.sup.3+/AC. Amongst zeolitic materials, Cu.sup.+/Y has been
reported to be the most effective.
[0005] Additionally, U.S. Pat. No. 9,719,028 discloses a method for
predicting selective performance of an adsorbent where the
adsorbent is selected from a list of metals and/or metal cations
for use in removing contaminants as thiophene derivatives in a
hydrocarbon feed. The metals or metal cations were identified from
a list having a positive value for Ere, wherein the metal or metal
cation having the largest value for Emi is the most selective
adsorbent. U.S. Pat. No. 9,719,028 studied competitive interaction
between transition metals and thiophene and derivatives, and their
aromatic counterparts of comparable aromaticity in the gas phase
using a computation simulation approach. U.S. Pat. No. 9,719,028
teaches adsorption selectivity of thiophenes over aromatics
dramatically changed with even a slight difference in charges of
same metal ions.
[0006] What has not been identified in these studies are adsorbents
capable of removing aromatic sulfur compounds such as
benzothiophene, dibenzothiophene, and other thiophene derivatives
from a liquid hydrocarbon feed steam containing aromatics with a
similar aromaticity or same ring number as the aromatic sulfur
compounds. This is an important issue, since liquid fuels, such as
hydrotreated diesel, contain much higher concentrations of arenes
(often more than 10%) than of thiophene derivatives (often less
than 50 ppm) following deep hydro-desulfurization.
[0007] Thus there is still a need for improved adsorbents that will
preferentially remove sulfur compounds from hydrocarbon feed
streams, such as liquid hydrocarbon feed streams. More
specifically, there is still a need for improved adsorbents that
will preferentially remove aromatic sulfur compounds including
benzothiophene, dibenzothiophene, and derivatives thereof from
liquid fuels containing arenes.
SUMMARY
[0008] In one aspect, the invention relates to a method for
removing sulfur compounds from a hydrocarbon feed stream, such as a
liquid hydrocarbon feed stream. The method comprises the steps of:
a) providing a first hydrocarbon feed stream, which is contaminated
with sulfur compounds; and b) passing the first hydrocarbon feed
stream through a desulfurization system comprising a metal
nanoparticle-deposited, nitrogen-doped carbon adsorbent to produce
a second hydrocarbon feed stream which has a substantially reduced
concentration of sulfur compounds as compared to the first
hydrocarbon feed stream. In some embodiments, the second
hydrocarbon feed stream had a concentration of sulfur compounds in
the second hydrocarbon feed stream which were from about 50% to
about 99.9% less than the concentration of sulfur compounds in the
first hydrocarbon feed stream. In some embodiments, the present
invention provides a method for removing sulfur compounds from a
hydrocarbon feed stream comprising: a) providing a first
hydrocarbon feed stream, which is contaminated with sulfur
compounds; and b) passing the first hydrocarbon feed stream through
a desulfurization system comprising a metal nanoparticle-deposited,
nitrogen-doped carbon adsorbent to produce a second hydrocarbon
feed stream which has about 30% to about 99.9% by weight less
sulfur compounds than the first hydrocarbon feed stream.
[0009] In another aspect, the invention relates to a nitrogen-doped
carbon adsorbent, produced by a process comprising: a) contacting
at least one nitrogen precursor and a suitable first
metal-containing salt in a first strong acid solution; b)
contacting the product of a) and an oxidant; c) heating the product
of b), thereby producing the nitrogen-doped carbon adsorbent.
[0010] In yet another aspect, the present invention provides a
metal nanoparticle-deposited, nitrogen-doped carbon adsorbent,
produced by a process comprising: a) contacting at least one
nitrogen precursor and a suitable first metal-containing salt in a
first strong acid solution; b) contacting the product of a) and an
oxidant; c) heating the product of b); d) contacting the product of
c) with a second strong acid solution; e) heating the product of
d); and f) contacting a nitrogen-doped carbon adsorbent with a
second metal-containing salt; thereby producing the metal
nanoparticle-deposited, nitrogen-doped carbon adsorbent.
[0011] A general embodiment of the disclosure is a metal
nanoparticle-deposited, nitrogen-doped carbon adsorbent, produced
by a process comprising: a) contacting at least one nitrogen
precursor and a suitable first metal-containing salt in a first
strong acid solution; b) contacting a product of a) and an oxidant;
c) heating a product of b) in an inert atmosphere; d) contacting a
product of c) with a second strong acid solution; e) heating a
product of d) in an inert atmosphere, f) contacting a
nitrogen-doped carbon adsorbent with a second metal-containing
salt; thereby producing the metal nanoparticle-deposited,
nitrogen-doped carbon adsorbent. Another embodiment can be a method
of making a metal nanoparticle-deposited, nitrogen-doped carbon
absorbent. In some embodiments, the second metal-containing salt is
a gold-containing salt, and the metal nanoparticle-deposited,
nitrogen-doped carbon adsorbent is a gold nanoparticle-deposited,
nitrogen-doped carbon adsorbent. In certain embodiments, said a) is
contacting two nitrogen precursors and the suitable first
metal-containing salt in a first strong acid solution. In a further
embodiment, said two nitrogen precursors are a first nitrogen
precursor which is aniline and a second nitrogen precursor which is
cyanimide. In one embodiment, said b) is contacting the product of
a) and (NH.sub.4).sub.2S.sub.2O.sub.8, thus forming an oxidized
product, and contacting said oxidized product with an aqueous
solution containing carbon black and a low molecular weight
alcohol. In some instances, said c) is heating the product of b) to
a first temperature of from about 35.degree. C. to about
100.degree. C., and then to a second temperature of from about
500.degree. C. to about 1000.degree. C. In embodiments, said d) is
contacting the product of c) with either an H.sub.2SO.sub.4
solution or a HNO.sub.3 solution. In certain embodiments, said e)
is heating the product of d) from about 500.degree. C. to about
1000.degree. C. Further, f) can comprise a reducing agent, or f)
may not comprise a reducing agent. In an embodiment, the second
strong acid has a pH of less than 3, less than 2, less than 1, or
less than 0.5. In an embodiment, the first strong acid has a pH of
less than 3, less than 2, less than 1, or less than 0.5.
[0012] Another general embodiment is a method for removing sulfur
compounds from a hydrocarbon feed stream comprising: a) providing a
first hydrocarbon feed stream, which is contaminated with the
sulfur compounds; and b) passing the first hydrocarbon feed stream
through a desulfurization system comprising the metal
nanoparticle-deposited, nitrogen-doped carbon adsorbent of the
disclosure, to produce a second hydrocarbon feed stream which has
about 30% to about 99.9% by weight less of the sulfur compounds
than the first hydrocarbon feed stream. The hydrocarbon feed stream
can be a liquid hydrocarbon feed stream. In some embodiments, the
liquid hydrocarbon feed stream is selected from the group
consisting of diesel fuel, jet fuel, gasoline, kerosene, compressed
natural gas, and liquefied petroleum gas (LPG). Further, the sulfur
compounds can comprise dibenzothiophene (DBT) and/or
4,6-dimethyldibenzothiophene (DMDBT).
[0013] The present invention may suitably comprise, consist of, or
consist essentially of, the elements in the claims, as described
herein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 summarizes synthesis conditions and desulfurization
capacities of adsorbent samples A-C and E-G. K.J. is
Ketjenblack.
[0015] FIG. 2 summarizes synthesis conditions and desulfurization
capacities of adsorbent samples D, H-J, and L-N. K.J. is
Ketjenblack.
[0016] FIG. 3 summarizes synthesis conditions and desulfurization
capacities of adsorbent samples P, S, and U. K.J. is
Ketjenblack.
[0017] FIG. 4 shows equilibrium sulfur removal percentages
(R.sub.equi.) for Samples S and U.
DETAILED DESCRIPTION
I. Definitions and Abbreviations
[0018] As used herein, the singular forms "a," "an", and "the"
include plural references unless the context clearly dictates
otherwise. For example, reference to "an active agent" includes a
single active agent as well as two or more different active agents
in combination. It is to be understood that present teaching is not
limited to the specific dosage forms, carriers, or the like,
disclosed herein and as such may vary.
[0019] The abbreviations used herein generally have their
conventional meaning within the chemical and biological arts.
[0020] Where substituent groups are specified by their conventional
chemical formulae, written from left to right, they equally
encompass the chemically identical substituents, which would result
from writing the structure from right to left, e.g., --CH.sub.2O--
is intended to also recite --OCH.sub.2--.
[0021] The term "poly" as used herein means at least 2. For
example, a polyvalent metal ion is a metal ion having a valency of
at least 2.
[0022] "Moiety" refers to a radical of a molecule that is attached
to the remainder of the molecule.
[0023] The term "sulfur compounds" refers to sulfur compounds
having a boiling point within or about the boiling point range of
liquid fuel. Examples of sulfur compounds include thiophenes,
disulfides, sulfoxides, mercaptans, and derivatives thereof.
Examples of sulfur compounds also include higher molecular weight
organic sulfur-containing compounds including, benzothiophene and
dibenzothiophene derivatives optionally substituted with 1-4 groups
each independently selected from the group consisting of linear or
branched alkyl, heteroalkyl, cycloalkyl, heterocycloalkyl, aryl,
heteroaryl, naphthenic and hetero-naphthenic derivatives, and
derivatives thereof. Examples of sulfur compounds also include
benzothiophene, dibenzothiophene (DBT),
4,6-dimethyldibenzothiophene (DMDBT).
[0024] The term "hydrocarbon feed stream" refers to gas or liquid
fuels. In an exemplary embodiment, the hydrocarbon feed stream is a
liquid fuel. In an exemplary embodiment, the hydrocarbon feed
stream is a liquid fuel which is diesel fuel, jet fuel, gasoline,
kerosene, compressed natural gas, or liquefied petroleum gas
(LPG).
[0025] The term "metal nanoparticle-deposited, nitrogen-doped
carbon adsorbent" refers to the composites in which nanoscale metal
particles are deposited onto nitrogen-doped carbons, or namely
metal/carbon nanocomposite adsorbents hereafter.
[0026] The term "nanoparticle" refers to particles that have a mean
diameter of between 1 to 1000 nanometers and less than that of
microparticles.
[0027] The term "compounds having a boiling point within or about
the boiling point range of liquid fuel" refers to any liquid fuels
with boiling point above about 180.degree. F., such as from about
180.degree. F. to about 750.degree. F. In an exemplary embodiment,
the liquid fuels have a boiling point above about 250.degree. F.,
such as from about 250.degree. F. to about 750.degree. F. The term
"compounds having a boiling point within or about the boiling point
range of liquid fuel" refers to any liquid fuels with boiling point
above 180.degree. F., or preferably above 250.degree. F. Test
methods for boiling range determinations are located in the most
current versions of ASTM D 2887 and ASTM D 6352. The test method is
referred to herein as "SimDist". The boiling range determination by
distillation is simulated by the use of gas chromatography. The
boiling range distributions obtained by this test method are
essentially equivalent to those obtained by true boiling point
(TBP)distillation (see ASTM Test Method D 2892), but are not
equivalent to results from low efficiency distillations such as
those obtained with ASTM Test Methods D 86 or D 1160. Light naphtha
fuel has a boiling point range of from about C.sub.5 to about
180.degree. F. (from about C.sub.5 to about 82.degree. C.). Heavy
naphtha fuel has a boiling point range of from about 180.degree. F.
to about 300.degree. F. (from about 82.degree. C. to about
149.degree. C.). Jet fuel has a boiling point range of from about
300.degree. F. to about 380.degree. F. (from about 149.degree. C.
to about 193.degree. C.). Kerosene fuel has a boiling point range
of from about 380.degree. F. to about 530.degree. F. (from about
193.degree. C. to about 277.degree. C.). Diesel fuel has a boiling
point range of from about 530.degree. F. to about 700.degree. F.
(from about 277.degree. C. to about 371.degree. C.). The test
methods used for boiling range distributions and boiling points of
the compositions in this disclosure are the most current versions
of ASTM D 2887 and ASTM D 6352.
[0028] The term "higher molecular weight organic sulfur-containing
compounds" refers to at least 2-ring polycyclic aromatics with at
least one carbon atom in the aromatic ring being replaced by S
atom. In an exemplary embodiment, the higher molecular weight
organic sulfur-containing compounds include benzothiophenes,
dibenzothiophenes, and their derivatives, optionally substituted
with one or multiple groups consisting of linear or branched alkyl,
cycloalkyl, aryl, naphthenic and derivatives, and derivatives
thereof.
[0029] The term "liquid hourly space velocity" (LHSV) refers to a
method for relating the reactant liquid flow rate to the reactor
volume at a standard temperature. LHSV is the ratio of the hourly
volume of the hydrocarbon feed stream being processed to the volume
of adsorbent. It is generally expressed as v/v/hr or hr.sup.-1.
[0030] "Solvent" as used herein is intended to include a wide
variety of solvents including organic solvents, aromatic solvents,
nitrogen-containing polar organic solvents, and oxygen-containing
polar organic solvents. Examples of organic solvents include acetic
acid, acetone, acetonitrile, benzene, toluene, benzonitrile, benzyl
alcohol, 1-butanol, 2-butanol, n-butanol, 2-butaone, 2-t-butyl
alcohol, carbon tetrachloride, chlorobenzene, 1,2-dichlorobenzene,
1,2-difluorobenzene, chloroform, cyclohexane, 1,2-dichloroethane,
diethylene glycol, diethyl ether, dimethylacetamide (DMAc),
dimethyl ether diglyme (diethylene glycol dimethyl ether),
1-diethylaminoethanol, diethylformamide, 1,2-dimethoxy-ethane
(glyme, DME), dimethylformamide (DMF), dioxane, 1,4-dioxane,
ethanol, ethyl acetate, ethylene dichloride, ethylene glycol,
formic acid, glycerin, heptane, hexamethylphosphoramide (HMPA),
hexamethylphosphorous triamide (HMPT), hexanes, isopropanol,
methanol, methyl t-butyl ether (MTBE), methylene chloride,
N-methyl-2-pyrrolidinone (NMP), nitromethane, pentane, petroleum
ether (ligroine), 1-propanol, 2-propanol, n-propanol, pyridine,
tetrahydrofuran (THF), toluene, triethyl amine, o-xylene, m-xylene,
and p-xylene. Examples of aromatic solvents include benzene,
benzonitrile, benzenethiol, benzyl alcohol, chlorobenzene,
1,2-dichlorobenzene, 1,2-difluorobenzene, hexafluorobenzene,
mesitylene, nitrobenzene, phenol, pyridine, tetralin, toluene,
1,2,4-trichlorobenzene, trifluorotoluene, and xylene. Examples of
nitrogen-containing polar organic solvents include acetonitrile,
benzonitrile, dimethylformamide (DMF), diethylformamide,
1-diethylaminoethanol, dimethylacetamide (DMAc),
hexamethylphosphorous triamide (HMPT), hexamethylphosphoramide
(HMPA), N-methyl-2-pyrrolidinone (NMP), nitromethane, pyridine, and
triethyl amine. Examples of oxygen-containing polar organic
solvents include acetic acid, acetone, benzyl alcohol, 1-butanol,
2-butanol, n-butanol, 2-butaone, 2-t-butyl alcohol, diethylene
glycol, diethyl ether, dimethylacetamide (DMAc), dimethyl ether
diglyme (diethylene glycol dimethyl ether), 1-diethylaminoethanol,
diethylformamide, 1,2-dimethoxy-ethane (glyme, DME),
dimethyl-formamide (DMF), dimethyl sulfoxide (DMSO), dioxane,
1,4-dioxane, ethanol, ethyl acetate, ethylene glycol, formic acid,
glycerin, hexamethylphosphoramide (HMPA), hexamethylphosphorous
triamide (HMPT), isopropanol, methanol, methyl t-butyl ether
(MTBE), N-methyl-2-pyrrolidinone (NMP), 1-propanol, 2-propanol,
n-propanol, and tetrahydrofuran (THF).
[0031] The term "alkyl," by itself or as part of another
substituent, means, unless otherwise stated, a straight or branched
chain, or cyclic hydrocarbon radical, or combination thereof, which
may be fully saturated, mono- or polyunsaturated and can include
di- and multivalent radicals, having the number of carbon atoms
designated (i.e. C.sub.1-C.sub.10 means one to ten carbons). In
some embodiments, the term "alkyl" means a straight or branched
chain, or combinations thereof, which may be fully saturated, mono-
or polyunsaturated and can include di- and multivalent radicals.
Examples of saturated hydrocarbon radicals include, but are not
limited to, groups such as methyl, ethyl, n-propyl, isopropyl,
n-butyl, t-butyl, isobutyl, sec-butyl, cyclobutyl, cyclohexyl,
(cyclohexyl)methyl, cyclopropyl, cyclopropylmethyl, homologs and
isomers of, for example, n-pentyl, n-hexyl, n-heptyl, n-octyl, and
the like. Alkyl can include any number of carbons, such as 1-2,
1-3, 1-4, 1-5, 1-6, 1-7, 1-8, 1-9, 1-10, 2-3, 2-4, 2-5, 2-6, 3-4,
3-5, 3-6, 4-5, 4-6 and 5-6. The alkyl group is typically
monovalent, but can be divalent, such as when the alkyl group links
two moieties together.
[0032] An unsaturated alkyl group is one having one or more double
bonds or triple bonds. Examples of unsaturated alkyl groups
include, but are not limited to, vinyl, 2-propenyl, crotyl,
2-isopentenyl, 2-(butadienyl), 2,4-pentadienyl,
3-(1,4-pentadienyl), ethynyl, 1- and 3-propynyl, 3-butynyl, and the
higher homologs and isomers.
[0033] Substituents for the optionally substituted groups can be a
variety of groups selected from: R', --OR', .dbd.O, .dbd.NR',
.dbd.N--OR', --NR'R'', --SR', -halogen, --SiR'R''R''', --OC(O)R',
--C(O)R', --CO.sub.2R', --CONR'R'', --OC(O)NR'R'', --NR''C(O)R',
--NR'--C(O)NR''R''', --NR''C(O).sub.2R', --NR--C(NR'R'').dbd.NR''',
--NH--C(NH.sub.2).dbd.NH, --NR'C(NH.sub.2).dbd.NH,
--NH--C(NH.sub.2).dbd.NR', --S(O)R', --S(O).sub.2R',
--S(O).sub.2NR'R'', --CN and --NO.sub.2 in a number ranging from
zero to (2m'+1), where m' is the total number of carbon atoms in
such radical. R', R'' and R''' each independently refer to
hydrogen, unsubstituted (C.sub.1-C.sub.8) alkyl and heteroalkyl,
unsubstituted aryl, aryl substituted with 1-3 halogens,
unsubstituted alkyl, alkoxy or thioalkoxy groups, or
aryl-(C.sub.1-C.sub.4)alkyl groups. When a compound of the
invention includes more than one R group, for example, each of the
R groups is independently selected as are each R', R'', and R'''
groups when more than one of these groups is present. When R' and
R'' are attached to the same nitrogen atom, they can be combined
with the nitrogen atom to form a 5-, 6-, or 7-membered ring. For
example, --NR'R'' is meant to include, but not be limited to,
1-pyrrolidinyl and 4-morpholinyl. From the above discussion of
substituents, one of skill in the art will understand that the term
"alkyl" is meant to include groups including carbon atoms bound to
groups other than hydrogen groups, such as haloalkyl (e.g.,
--CF.sub.3 and --CH.sub.2CF.sub.3) and acyl (e.g., --C(O)CH.sub.3,
--C(O)CF.sub.3, --C(O)CH.sub.2OCH.sub.3, and the like) which are
also preferred and contemplated by the present invention.
[0034] As used herein, the term "alkylene" refers to an alkyl
group, as defined above, linking at least two other groups, i.e., a
divalent hydrocarbon radical. The two moieties linked to the
alkylene can be linked to the same atom or different atoms of the
alkylene. For instance, a straight chain alkylene can be the
bivalent radical of --(CH.sub.2).sub.n, where n is 1, 2, 3, 4, 5 or
6. Alkylene groups include, but are not limited to, methylene,
ethylene, propylene, isopropylene, butylene, isobutylene,
sec-butylene, pentylene and hexylene.
[0035] The term "aryl" means, unless otherwise stated, a
polyunsaturated, aromatic, substituent that can be a single ring or
multiple rings (preferably from 1 or 2 or 3 rings), which are fused
together or linked covalently
[0036] For brevity, the term "aryl" when used in combination with
other terms (e.g., aryloxy, arylthioxy, arylalkyl) includes both
aryl and heteroaryl rings as defined above. Thus, the term
"arylalkyl" is meant to include those radicals in which an aryl
group is attached to an alkyl group (e.g., benzyl, phenethyl,
pyridylmethyl and the like) including those alkyl groups in which a
carbon atom (e.g., a methylene group) has been replaced by, for
example, an oxygen atom (e.g., phenoxymethyl, 2-pyridyloxymethyl,
3-(1-naphthyloxy)propyl, and the like).
[0037] Each of the above terms (e.g., "alkyl," "aryl," and
"heteroaryl") are meant to include both substituted and
unsubstituted forms of the indicated radical. Preferred
substituents are provided below.
[0038] Substituents for the alkyl and heteroalkyl radicals
(including those groups often referred to as alkylene, alkenyl,
heteroalkylene, heteroalkenyl, alkynyl, cycloalkyl,
heterocycloalkyl, cycloalkenyl, and heterocycloalkenyl) are
generically referred to as "alkyl group substituents," and they can
be one or more of a variety of groups selected from, but not
limited to: --R', --OR', .dbd.O, .dbd.NR', .dbd.N--OR', --NR'R'',
--SR', -halogen, --SiR'R''R''', --OC(O)R', --C(O)R', --CO.sub.2R',
--CONR'R'', --OC(O)NR'R'', --NR''C(O)R', --NR'--C(O)NR''R''',
--NR''C(O).sub.2R', --NR'''' '--C(NR'R''R''').dbd.NR'''',
--NR''''--C(NR'R'').dbd.NR''', --S(O)R', --S(O).sub.2R',
--S(O).sub.2NR'R'', --NR''SO.sub.2R', --CN, --NO.sub.2, --N.sub.3,
--CH(Ph).sub.2, fluoro(C.sub.1-C.sub.4)alkoxy, and
fluoro(C.sub.1--C.sub.4)alkyl, in a number ranging from zero to
(2m'+1), where m' is the total number of carbon atoms in such
radical. R', R'', R''', R'''' and R''''' each preferably
independently refer to hydrogen, substituted or unsubstituted
haloalkyl, substituted or unsubstituted heteroalkyl, substituted or
unsubstituted heterocycloalkyl, substituted or unsubstituted aryl,
e.g., aryl substituted with 1-3 halogens, substituted or
unsubstituted alkyl, alkoxy or thioalkoxy groups, or arylalkyl
groups. When a compound of the invention includes more than one R
group, for example, each of the R groups is independently selected
as are each R', R'', R''', R'''' and R''''' groups when more than
one of these groups is present. When R' and R'' are attached to the
same nitrogen atom, they can be combined with the nitrogen atom to
form a 5-, 6-, or 7-membered ring. For example, --NR'R'' is meant
to include, but not be limited to, 1-pyrrolidinyl and
4-morpholinyl. From the above discussion of substituents, one of
skill in the art will understand that the term "alkyl" is meant to
include groups including carbon atoms bound to groups other than
hydrogen groups, such as haloalkyl (e.g., --CF.sub.3 and
--CH.sub.2CF.sub.3) and acyl (e.g., --C(O)CH.sub.3, --C(O)CF.sub.3,
--C(O)CH.sub.2OCH.sub.3, and the like).
[0039] Similar to the substituents described for the alkyl radical,
substituents for the aryl and heteroaryl groups are generically
referred to as "aryl group substituents." The substituents are
selected from, for example: --R', --OR', .dbd.O, .dbd.NR',
.dbd.N--OR', --NR'R'', --SR', halogen, --SiR'R''R''', --OC(O)R',
--C(O)R', --CO.sub.2R', --CONR'R'', --OC(O)NR'R'', --NR''C(O)R',
--NR'--C(O)NR''R''', --NR''C(O).sub.2R', --NR''.
--C(NR'R''R''').dbd.NR'''', --NR''''--C(NR'R'').dbd.NR''',
--S(O)R', --S(O).sub.2R', --S(O).sub.2NR'R'', --NR''SO.sub.2R',
--CN, --NO.sub.2, --N.sub.3, --CH(Ph).sub.2,
fluoro(C.sub.1-C.sub.4)alkoxy, and fluoro(C.sub.1-C.sub.4)alkyl, in
a number ranging from zero to the total number of open valences on
the aromatic ring system; and where R', R'', R''', R'''' and R'''''
are preferably independently selected from hydrogen, substituted or
unsubstituted alkyl, substituted or unsubstituted heteroalkyl,
substituted or unsubstituted aryl and substituted or unsubstituted
heteroaryl. When a compound of the invention includes more than one
R group, for example, each of the R groups is independently
selected as are each R', R'', R''', R'''' and R''''' groups when
more than one of these groups is present.
[0040] Two of the substituents on adjacent atoms of the aryl or
heteroaryl ring may optionally be replaced with a substituent of
the formula -T-C(O)--(CRR').sub.q--U--, wherein T and U are
independently --NR--, --O--, --CRR'-- or a single bond, and q is an
integer of from 0 to 3. Alternatively, two of the substituents on
adjacent atoms of the aryl or heteroaryl ring may optionally be
replaced with a substituent of the formula
-A-(CH.sub.2).sub.r--B--, wherein A and B are independently
--CRR'--, --O--, --NR--, --S--, --S(O)--, --S(O).sub.2--,
--S(O).sub.2NR'-- or a single bond, and r is an integer of from 1
to 4. One of the single bonds of the new ring so formed may
optionally be replaced with a double bond. Alternatively, two of
the substituents on adjacent atoms of the aryl or heteroaryl ring
may optionally be replaced with a substituent of the formula
--(CRR').sub.s--X--(CR''R''').sub.d--, where s and d are
independently integers of from 0 to 3, and X is --O--, --NR'--,
--S--, --S(O)--, --S(O).sub.2--, or --S(O).sub.2NR'--. The
substituents R, R', R'' and R''' are preferably independently
selected from hydrogen or substituted or unsubstituted C.sub.1 or
C.sub.2 or C.sub.3 or C.sub.4 or C.sub.5 or C.sub.6 alkyl.
[0041] "Ring" as used herein, means a substituted or unsubstituted
cycloalkyl, substituted or unsubstituted heterocycloalkyl,
substituted or unsubstituted aryl, or substituted or unsubstituted
heteroaryl. A ring includes fused ring moieties. The number of
atoms in a ring is typically defined by the number of members in
the ring. For example, a "5- to 7-membered ring" means there are 5
or 6 or 7 atoms in the encircling arrangement. Unless otherwise
specified, the ring optionally includes a heteroatom. Thus, the
term "5 to 7-membered ring" or "5 or 6 or 7 membered ring"
includes, for example phenyl, pyridinyl and piperidinyl. The term
"5 to 7-membered heterocycloalkyl ring" "5 or 6 or 7-membered
heterocycloalkyl ring", on the other hand, would include pyridinyl
and piperidinyl, but not phenyl. The term "ring" further includes a
ring system comprising more than one "ring", wherein each "ring" is
independently defined as above.
[0042] As used herein, the term "heteroalkyl" refers to an alkyl
group having from 1 to 3 heteroatoms such as N, O and S. Additional
heteroatoms can also be useful, including, but not limited to, B,
Al, Si and P. The heteroatoms can also be oxidized, such as, but
not limited to, --S(O)-- and --S(O).sub.2--. For example,
heteroalkyl can include ethers, thioethers and alkyl-amines.
[0043] As used herein, the term "heteroalkylene" refers to a
heteroalkyl group, as defined above, linking at least two other
groups. The two moieties linked to the heteroalkylene can be linked
to the same atom or different atoms of the heteroalkylene.
[0044] As used herein, the term "heteroaryl" refers to a monocyclic
or fused bicyclic or tricyclic aromatic ring assembly containing 5
to 16 ring atoms, where from 1 to 4 of the ring atoms are a
heteroatom each N, O or S. For example, heteroaryl includes
pyridyl, indolyl, indazolyl, quinoxalinyl, quinolinyl,
isoquinolinyl, benzothienyl, benzofuranyl, furanyl, pyrrolyl,
thiazolyl, benzothiazolyl, oxazolyl, isoxazolyl, triazolyl,
tetrazolyl, pyrazolyl, imidazolyl, thienyl, or any other radicals
substituted, especially mono- or di-substituted, by e.g. alkyl,
nitro or halogen. Pyridyl represents 2-, 3- or 4-pyridyl,
advantageously 2- or 3-pyridyl. Thienyl represents 2- or 3-thienyl.
Quinolinyl represents preferably 2-, 3- or 4-quinolinyl.
Isoquinolinyl represents preferably 1-, 3- or 4-isoquinolinyl.
Benzopyranyl, benzothiopyranyl represents preferably 3-benzopyranyl
or 3-benzothiopyranyl, respectively. Thiazolyl represents
preferably 2- or 4-thiazolyl, and most preferred, 4-thiazolyl.
Triazolyl is preferably 1-, 2- or 5-(1,2,4-triazolyl). Tetrazolyl
is preferably 5-tetrazolyl.
[0045] Preferably, heteroaryl is pyridyl, indolyl, quinolinyl,
pyrrolyl, thiazolyl, isoxazolyl, triazolyl, tetrazolyl, pyrazolyl,
imidazolyl, thienyl, furanyl, benzothiazolyl, benzofuranyl,
isoquinolinyl, benzothienyl, oxazolyl, indazolyl, or any of the
radicals substituted, especially mono- or di-substituted.
[0046] Similarly, substituents for the aryl and heteroaryl groups
are varied and are selected from: -halogen, --OR', --OC(O)R',
--NR'R'', --SR', --R', --CN, --NO.sub.2, --CO.sub.2R', --CONR'R'',
--C(O)R', --OC(O)NR'R'', --NR''C(O)R', --NR''C(O).sub.2R',
--NR'--C(O)NR''R''', --NH--C(NH.sub.2).dbd.NH,
--NR'C(NH.sub.2).dbd.NH, --NH--C(NH.sub.2).dbd.NR', --S(O)R',
--S(O).sub.2R', --S(O).sub.2NR'R'', --N.sub.3, --CH(Ph).sub.2,
perfluoro(C.sub.1-C.sub.4)alkoxy, and
perfluoro(C.sub.1-C.sub.4)alkyl, in a number ranging from zero to
the total number of open valences on the aromatic ring system; and
where R', R'' and R''' are independently selected from hydrogen,
(C.sub.1-C.sub.8)alkyl and heteroalkyl, unsubstituted aryl and
heteroaryl, (unsubstituted aryl)-(C.sub.1-C.sub.4)alkyl, and
(unsubstituted aryl)oxy-(C.sub.1-C.sub.4)alkyl.
[0047] As used herein, the term "heterocycloalkyl" refers to a ring
system having from 3 ring members to about 20 ring members and from
1 to about 5 heteroatoms such as N, O and S. Additional heteroatoms
can also be useful, including, but not limited to, B, Al, Si and P.
The heteroatoms can also be oxidized, such as, but not limited to,
--S(O)-- and --S(O).sub.2--. For example, heterocycle includes, but
is not limited to, tetrahydrofuranyl, tetrahydrothiophenyl,
morpholino, pyrrolidinyl, pyrrolinyl, imidazolidinyl, imidazolinyl,
pyrazolidinyl, pyrazolinyl, piperazinyl, piperidinyl, indolinyl,
quinuclidinyl and 1,4-dioxa-8-aza-spiro[4.5]dec-8-yl. As used
herein, the term "heterocyclalkylene" refers to a heterocyclalkyl
group, as defined above, linking at least two other groups. The two
moieties linked to the heterocyclalkylene can be linked to the same
atom or different atoms of the heterocyclalkylene.
[0048] As used herein "carbon" refers to suitable carbon additives
including carbon blacks. Carbon black is a material produced by the
incomplete combustion of heavy petroleum products such as fluid
catalytic cracker (FCC) tar, coal tar, ethylene cracking tar, and a
small amount from vegetable oil. Carbon blacks include subtypes,
such as acetylene black, channel black, furnace black, lamp black,
and thermal black. Examples of carbon blacks include Ketjenblack
EC300J, Ketjenblack EC600JD, Black Pearls 2000, Vulcan XC-72,
Vulcan P, Sterling C, Norit A, Darco G-60, activated carbon,
MV-B-1500 and MWV 295-R-03 activated carbons.
[0049] The symbol "R" is a general abbreviation that represents a
substituent group that is selected from substituted or
unsubstituted alkyl, substituted or unsubstituted heteroalkyl,
substituted or unsubstituted aryl, substituted or unsubstituted
heteroaryl, substituted or unsubstituted cycloalkyl and substituted
or unsubstituted heterocycloalkyl groups.
[0050] "Periodic Table" refers to the International Union of Pure
& Applied Chemistry (IUPAC) Periodic Table of the Elements,
version dated 28 Nov. 2016.
[0051] The term "substantially", as used herein, is meant to
include a range from 20% to 100%. In an exemplary embodiment,
"substantially includes a range from 20% to about 30%, from about
30% to about 40%, from about 40% to about 50%, from about 50% to
about 60%, from about 60% to about 70%, from about 70% to about
80%, from about 80% to about 90%, from about 90% to about 99.5%,
from about 90% to about 99.9%, from about 90% to 100%, from 20% to
about 40%, from about 30% to about 50%, from about 40% to about
60%, from about 50% to about 70%, from about 60% to about 80%, from
about 70% to about 90%, from about 80% to 100%, from about 80% to
about 99.5%, from 20% to about 50%, from about 30% to about 60%,
from about 40% to about 70%, from about 50% to about 80%, from
about 60% to about 90%, from about 70% to about 99.5%, from 20% to
about 60%, from about 30% to about 70%, from about 40% to about
80%, from about 50% to about 90%, from about 60% to about 99.5%,
from 20% to about 70%, from about 30% to about 80%, from about 40%
to about 90%, from about 50% to about 99.5%, from 20% to about 80%,
from about 30% to about 90%, from about 40% to about 99.5%, from
about 30% to about 90%, and from about 30% to about 99.5%.
II. Introduction
[0052] In some embodiments, the invention provides a novel
adsorbent. The novel adsorbent can be used for removing sulfur
compounds from hydrocarbon feed streams, particularly for removing
sulfur compounds from liquid fuels.
III. The Adsorbents
[0053] In an exemplary embodiment, the adsorbent comprises a
nitrogen-doped carbon adsorbent. In an exemplary embodiment, the
adsorbent is a nitrogen-doped carbon adsorbent. In an exemplary
embodiment, the nitrogen-doped carbon adsorbent does not comprise a
metal nanoparticle. In an exemplary embodiment, the adsorbent
comprises a metal nanoparticle-deposited, nitrogen-doped carbon
adsorbent. In an exemplary embodiment, the adsorbent is a metal
nanoparticle-deposited, nitrogen-doped carbon adsorbent. The
adsorbents of the present invention can have any adsorbent
structure including amorphous, crystalline, and mixtures
thereof.
IIIa. Nitrogen-Doped Carbon Adsorbents
[0054] In an exemplary embodiment, the adsorbent comprises a
nitrogen-doped carbon adsorbent. In an exemplary embodiment, the
adsorbent is a nitrogen-doped carbon adsorbent. In an exemplary
embodiment, the nitrogen-doped carbon adsorbent does not comprise a
metal nanoparticle. In an exemplary embodiment, the adsorbent is
prepared by a process described herein. In an exemplary embodiment,
the adsorbent is prepared by a process found in the Examples. The
adsorbents of the present invention can have any adsorbent
structure including amorphous, crystalline, and mixtures
thereof.
IIIb. Synthesis of Nitrogen-Doped Carbon Adsorbents
[0055] In an exemplary embodiment, the nitrogen-doped carbon
adsorbent is produced by a process comprising: [0056] a) contacting
at least one nitrogen precursor and a suitable first
metal-containing salt in a first strong acid solution; [0057] b)
contacting the product of a) and an oxidant; [0058] c) heating the
product of b); thereby producing the nitrogen-doped carbon
adsorbent.
[0059] In an exemplary embodiment, the nitrogen precursor comprises
aniline. In an exemplary embodiment, the nitrogen precursor is
aniline. In an exemplary embodiment, the nitrogen precursor is
aniline, pyrrole, phenanthroline, melamine, urea, purine, pyrazine,
bipyridine, cyanimide, dicyanimide, or oxalate, or a combination
thereof. In an exemplary embodiment, the nitrogen precursor is
pyrrole, phenanthroline, melamine, urea, purine, pyrazine,
bipyridine, or a combination thereof. In an exemplary embodiment,
the nitrogen precursor is cyanimide. In an exemplary embodiment,
the nitrogen precursor is cyanimide, dicyanamide, or oxalate, or a
combination thereof. In an exemplary embodiment, the nitrogen
precursor is cyanimide. In an exemplary embodiment, the nitrogen
precursor comprises aniline and cyanimide. In an exemplary
embodiment, the nitrogen precursor comprises aniline and
dicyanimide. In an exemplary embodiment, the nitrogen precursor
comprises aniline and oxalate. In an exemplary embodiment, the
nitrogen precursor comprises cyanimide. In an exemplary embodiment,
the process comprises a) contacting a first nitrogen precursor and
a second nitrogen precursor and a suitable first metal-containing
salt in a first strong acid solution. In an exemplary embodiment,
the first nitrogen precursor is aniline and the second nitrogen
precursor is cyanimide.
[0060] In an exemplary embodiment, the first metal in the suitable
metal-containing salt is selected from the group consisting of
metals of periodic table Period 4/Group 4-12. In an exemplary
embodiment, the first metal in the suitable metal-containing salt
is selected from the group consisting of Mn, Fe, Co, Ni, Cu, and
Zn. In an exemplary embodiment, the suitable first metal-containing
salt is a suitable salt of Fe or a suitable salt of Ni. In an
exemplary embodiment, the suitable first metal-containing salt is
selected from the group consisting of iron fluoride, iron chloride,
iron bromide, iron iodide, iron acetate, iron nitrate, iron
sulfate, iron phosphate, iron oxalate, nickel fluoride, nickel
chloride, nickel bromide, nickel iodide, nickel acetate, nickel
nitrate, nickel sulfate, nickel oxalate, nickel carbonate, and
nickel cyclohexanebutyrate. In an exemplary embodiment, the
suitable first metal-containing salt is iron chloride. In an
exemplary embodiment, the suitable first metal-containing salt is
nickel chloride.
[0061] In an exemplary embodiment, the contacting of a) occurs
under conditions sufficient to dissolve the nitrogen precursor and
the first metal-containing salt. In an exemplary embodiment, the
contacting of a) occurs at a temperature of from about 0.degree. C.
to about 120.degree. C., or from about 0.degree. C. to about
100.degree. C., or from about 10.degree. C. to about 100.degree.
C., or from about 5.degree. C. to about 50.degree. C., from about
10.degree. C. to about 30.degree. C., or at about room temperature.
In an exemplary embodiment, the contacting of a) occurs at a time
of from about 1 sec to about 24 hours, or from about 1 min to about
18 hours, or from about 30 min to about 12 hours, or from about 1
hour to about 6 hours. In an exemplary embodiment, the ratio of
equivalents of the nitrogen precursor to equivalents of the
suitable first metal-containing salt is from about 1:1 to about
1:30, or from about 1:1 to about 1:10, or from 10:1 to about 1:1,
or from 30:1 to about 1:1. In an exemplary embodiment, the ratio of
equivalents of the nitrogen precursor to equivalents of the
suitable first metal-containing salt is from about 1:1 to about
1:5, or from 1:1 to about 1:4, or from 1:1 to about 1:3, or from
1:1 to about 1:2.5, or from 1:1 to about 1:2.3, or from 1:1 to
about 1:2.1, or from 1:1 to about 1:2, or from 1:1 to about 1:1.9,
or from 1:1 to about 1:1.8, or from 1:1 to about 1:1.7, or from 1:1
to about 1:1.6, or from 1:1 to about 1:1.5, or from 1:1 to about
1:1.4, or from 1:1 to about 1:1.3, or from 1:1 to about 1:1.2, or
from 1:1 to about 1:1.1, or from 1:1.2 to about 1:3.2. In an
exemplary embodiment, the nitrogen precursor is a combination of
two nitrogen precursors described herein, and the ratio of the
first nitrogen precursor to the second nitrogen precursor is from
about 1:1 to about 1:5, or from 1:1 to about 1:4, or from 1:1 to
about 1:3, or from 1:1 to about 1:2.5, or from 1:1 to about 1:2.3,
or from 1:1 to about 1:2.1, or from 1:1 to about 1:1, or from 1:1
to about 1:1.9, or from 1:1 to about 1:1.8, or from 1:1 to about
1:1.7, or from 1:1 to about 1:1.6, or from 1:1 to about 1:1.5, or
from 1:1 to about 1:1.4, or from 1:1 to about 1:1.3, or from 1:1 to
about 1:1.2, or from 1:1 to about 1:1.1, or from 1:1.2 to about
1:3.2. In an exemplary embodiment, the ratio of equivalents of the
nitrogen precursor to equivalents of the suitable first
metal-containing salt is from about 5:1 to about 1:1, or from 4:1
to about 1:1, or from 5:1 to about 3:1, or from 5:1 to about 4:1,
or from 4:1 to about 1:1, or from 3:1 to about 1:1, or from 2.5:1
to about 1:1, or from 2.3:1 to about 1:1, or from 2.1:1 to about
1:1, or from 2:1 to about 1:1, or from 1.9:1 to about 1:1, or from
1.8:1 to about 1:1, or from 1.7:1 to about 1:1, or from 1.6:1 to
about 1:1, or from 1.5:1 to about 1:1, or from 1.4:1 to about 1:1,
or from 1.3:1 to about 1:1, or from 1.2:1 to about 1:1, or from
1.1:1 to about 1:1, or from 1.2:1 to about 3.2:1. In an exemplary
embodiment, the nitrogen precursor is a combination of two nitrogen
precursors described herein, and the ratio of the first nitrogen
precursor to the second nitrogen precursor is from about 5:1 to
about 1:1, or from 4:1 to about 1:1, or from 5:1 to about 3:1, or
from 5:1 to about 4:1, or from 4:1 to about 1:1, or from 3:1 to
about 1:1, or from 2.5:1 to about 1:1, or from 2.3:1 to about 1:1,
or from 2.1:1 to about 1:1, or from 2:1 to about 1:1, or from 1.9:1
to about 1:1, or from 1.8:1 to about 1:1, or from 1.7:1 to about
1:1, or from 1.6:1 to about 1:1, or from 1.5:1 to about 1:1, or
from 1.4:1 to about 1:1, or from 1.3:1 to about 1:1, or from 1.2:1
to about 1:1, or from 1.1:1 to about 1:1, or from 1.2:1 to about
3.2:1.
[0062] In an exemplary embodiment, the first nitrogen precursor is
aniline. In an exemplary embodiment, the second nitrogen precursor
is cyanimide. In an exemplary embodiment, the first nitrogen
precursor is aniline and the second nitrogen precursor is
cyanimide. In an exemplary embodiment, the first strong acid
solution in a) is any one which dissolves the nitrogen precursor
and the suitable first metal-containing salt. In an exemplary
embodiment, the first strong acid solution is an HCl solution. In
an exemplary embodiment, the first strong acid solution is an
H.sub.2SO.sub.4 or HNO.sub.3 solution. In an exemplary embodiment,
the first strong acid solution is an HI or HBr or HClO.sub.4 or
HClO.sub.3 solution. In an embodiment, a strong acid has a pH of
less than 3, less than 2, less than 1, or less than 0.5.
[0063] In an exemplary embodiment, the oxidant is selected from the
group consisting of (NH.sub.4).sub.2S.sub.2O.sub.8,
H.sub.2S.sub.2O.sub.8, H.sub.2SO.sub.4, H.sub.2SO, N.sub.2O,
HNO.sub.3, KNO.sub.3, O.sub.3, KMnO.sub.4, and H.sub.2O.sub.2. In
an exemplary embodiment, the oxidant is H.sub.2O.sub.2. In an
exemplary embodiment, the oxidant is
(NH.sub.4).sub.2S.sub.2O.sub.8.
[0064] In an exemplary embodiment, the contacting of b) occurs
under conditions sufficient to polymerize the nitrogen precursor.
In an exemplary embodiment, the contacting of b) occurs at a
temperature of from about 0.degree. C. to about 120.degree. C., or
from about 0.degree. C. to about 100.degree. C., or from about
10.degree. C. to about 100.degree. C., or from about 5.degree. C.
to about 50.degree. C., from about 10.degree. C. to about
30.degree. C., or at about room temperature. In an exemplary
embodiment, the contacting of b) occurs at a time of from about 1
sec to about 24 hours, or from about 1 min to about 18 hours, or
from about 30 min to about 12 hours, or from about 1 hour to about
6 hours, or from about 3 hours to about 5 hours. In an exemplary
embodiment, the ratio of equivalents of the oxidant to equivalents
of the product of a) is from about 1:1 to about 1:10, or from 10:1
to about 1:1. In an exemplary embodiment, the solvent in b) is any
one which dissolves the oxidant and the product of a). In an
exemplary embodiment, the ratio of equivalents of the oxidant to
equivalents of the product of a) is from about 1:1 to about 1:5, or
from 1:1 to about 1:4, or from 1:1 to about 1:3, or from 1:1 to
about 1:2.5, or from 1:1 to about 1:2.3, or from 1:1 to about
1:2.1, or from 1:1 to about 1:2, or from 1:1 to about 1:1.9, or
from 1:1 to about 1:1.8, or from 1:1 to about 1:1.7, or from 1:1.2
to about 1:2.2, or from 1:1.3 to about 1:2, or from 1:1 to about
1:1.6, or from 1:1 to about 1:1.5, or from 1:1 to about 1:1.4, or
from 1:1 to about 1:1.3, or from 1:1 to about 1:1.2, or from 1:1 to
about 1:1.1, or from 1:1.2 to about 1:3.2. In an exemplary
embodiment, the solvent in b) is a strong acid. In an exemplary
embodiment, the solvent in b) is HCl. In an exemplary embodiment,
the solvent in b) is H.sub.2SO.sub.4 or HNO.sub.3. In an exemplary
embodiment, the solvent in b) is HI or HBr or HClO.sub.4 or
HClO.sub.3. In an embodiment, a strong acid has a pH of less than
3, less than 2, less than 1, or less than 0.5. In an exemplary
embodiment, the contacting of b) occurs at about room temperature.
In an exemplary embodiment, the contacting of b) occurs at a time
of from about 3 hours to about 5 hours.
[0065] In an exemplary embodiment, the process comprises b)
contacting the product of a) and an oxidant, thus forming an
oxidized product, and contacting said oxidized product with a
carbon support. In an exemplary embodiment, the carbon support is a
carbon black selected from the group consisting of Ketjenblack
EC300J, Ketjenblack EC600JD, Black Pearls 2000, Vulcan XC-72,
Vulcan P, Sterling C, Norit A, Darco G-60, and activated carbon. In
an exemplary embodiment, the carbon support is a carbon black, and
said carbon black is an activated carbon, and the activated carbon
is MV-B-1500 and MWV 295-R-03. In an exemplary embodiment, the
carbon support is Ketjenblack EC300J. In an exemplary embodiment,
the carbon support is MWV 295-R-03. In an exemplary embodiment, the
carbon support is in an aqueous solution. In an exemplary
embodiment, the aqueous solution contains an alcohol. In an
exemplary embodiment, the aqueous solution contains a low molecular
weight alcohol. In an exemplary embodiment, the aqueous solution
contains isopropanol. In an exemplary embodiment, the contacting of
said oxidized product occurs at a temperature of from about
0.degree. C. to about 120.degree. C., or from about 0.degree. C. to
about 100.degree. C., or from about 10.degree. C. to about
100.degree. C., or from about 5.degree. C. to about 50.degree. C.,
or from about 10.degree. C. to about 30.degree. C., or at about
room temperature, or from about 50.degree. C. to about 100.degree.
C., or from about 60.degree. C. to about 90.degree. C., or from
about 75.degree. C. to about 85.degree. C., or from about
100.degree. C. to about 1000.degree. C., or from about 300.degree.
C. to about 700.degree. C., or from about 500.degree. C. to about
1000.degree. C., or from about 600.degree. C. to about 900.degree.
C., or from about 600.degree. C. to about 800.degree. C., or from
about 600.degree. C. to about 700.degree. C., or from about
600.degree. C. to about 1000.degree. C., or from about 700.degree.
C. to about 1000.degree. C., or from about 800.degree. C. to about
1000.degree. C., or from about 900.degree. C. to about 1000.degree.
C., or from about 700.degree. C. to about 900.degree. C., or from
about 700.degree. C. to about 800.degree. C. In an exemplary
embodiment, the contacting of said oxidized product occurs at a
time of from about 1 sec to about 24 hours, or from about 1 min to
about 18 hours, or from about 30 min to about 12 hours, or from
about 1 hour to about 6 hours, or from about 3 hours to about 5
hours, or from about 2 hours to about 4 hours. In an exemplary
embodiment, the ratio of equivalents of the carbon support to
equivalents of the oxidized product is from about 1:1 to about
1:10, or from 10:1 to about 1:1. In an exemplary embodiment, the
ratio of equivalents of the carbon support to equivalents of the
oxidized product is from about 1:1 to about 1:5, or from 1:1 to
about 1:4, or from 1:1 to about 1:3, or from 1:1 to about 1:2.5, or
from 1:1 to about 1:2.3, or from 1:1 to about 1:2.1, or from 1:1 to
about 1:2, or from 1:1 to about 1:1.9, or from 1:1 to about 1:1.8,
or from 1:1 to about 1:1.7, or from 1:1.2 to about 1:2.2, or from
1:1.3 to about 1:2, or from 1:1 to about 1:1.6, or from 1:1 to
about 1:1.5, or from 1:1 to about 1:1.4, or from 1:1 to about
1:1.3, or from 1:1 to about 1:1.2, or from 1:1 to about 1:1.1, or
from 1:1.2 to about 1:3.2. In an exemplary embodiment, the
contacting of b) occurs at a temperature of from about 60.degree.
C. to about 90.degree. C. In an exemplary embodiment, the
contacting of b) occurs at a time of from about 2 hours to about 4
hours.
[0066] In an exemplary embodiment, the contacting of c) occurs
under conditions sufficient to form the nitrogen-doped carbon
adsorbent. In an exemplary embodiment, the contacting of c) occurs
at a first temperature which essentially removes the solvent from
the previous step, and then at a second temperature which forms the
nitrogen-doped carbon adsorbent. In an exemplary embodiment, the
heating in c) occurs at a temperature of from about 0.degree. C. to
about 1000.degree. C., or from about 0.degree. C. to about
1200.degree. C., or from about 500.degree. C. to about 1200.degree.
C., or from about 500.degree. C. to about 1100.degree. C., or from
about 100.degree. C. to about 1000.degree. C., or from about
300.degree. C. to about 700.degree. C., or from about 500.degree.
C. to about 1000.degree. C., or from about 600.degree. C. to about
900.degree. C., or from about 600.degree. C. to about 800.degree.
C., or from about 600.degree. C. to about 700.degree. C., or from
about 600.degree. C. to about 1000.degree. C., or from about
700.degree. C. to about 1000.degree. C., or from about 800.degree.
C. to about 1000.degree. C., or from about 900.degree. C. to about
1000.degree. C., or from about 700.degree. C. to about 900.degree.
C., or from about 700.degree. C. to about 800.degree. C. In an
exemplary embodiment, the heating in c) occurs at a time of from
about 1 sec to about 24 hours, or from about 1 min to about 18
hours, or from about 30 min to about 12 hours, or from about 1 hour
to about 6 hours, or from about 3 hours to about 5 hours, or from
about 2 hours to about 4 hours, or from about 1 min to about 2
hours, or from about 30 min to about 90 min, or from about 45 min
to about 75 min, or about 60 min. In an exemplary embodiment, the
heating of c) occurs in an inert atmosphere. For example, the inert
atmosphere does not comprise oxygen. In one embodiment, the inert
atmosphere is an inert gas, such as nitrogen or argon. In an
exemplary embodiment, the heating of c) occurs in a nitrogen
atmosphere. In an exemplary embodiment, the heating of c) occurs at
a first temperature and for a time which essentially evaporates the
solvent, and then a second temperature for producing the
nitrogen-doped carbon adsorbent. In an exemplary embodiment, the
heating of c) occurs at a first temperature of from about
20.degree. C. to about 120.degree. C., and then occurs at a second
temperature of from about 500.degree. C. to about 1000.degree. C.
In an exemplary embodiment, the heating of c) occurs at a first
temperature of from about 20.degree. C. to about 100.degree. C. and
for a time in which the solvent essentially evaporates, and then
occurs at a second temperature of from about 500.degree. C. to
about 1000.degree. C. In an exemplary embodiment, the heating of c)
occurs at a first temperature of from about 35.degree. C. to about
100.degree. C., and then occurs at a second temperature of from
about 500.degree. C. to about 1000.degree. C. In an exemplary
embodiment, the heating in c) occurs at a time of from about 1 hour
to about 6 hours and at a temperature of from about 700.degree. C.
to about 1100.degree. C. In an exemplary embodiment, the heating in
c) occurs at a time of from about 2 hours to about 4 hours and at a
temperature of from about 800.degree. C. to about 1000.degree. C.
In an exemplary embodiment, the heating in c) occurs at a time of
from about 2 hours to about 4 hours and at a temperature of from
about 850.degree. C. to about 950.degree. C.
[0067] In an exemplary embodiment, the nitrogen-doped carbon
adsorbent is produced by a process further comprising d) contacting
the product of c) with a second strong acid solution. In an
exemplary embodiment, the nitrogen-doped carbon adsorbent is
produced by a process further comprising d) contacting the product
of c) with a second strong acid solution, followed by washing with
water. In an exemplary embodiment, the contacting of d) occurs at a
temperature of from about 0.degree. C. to about 120.degree. C., or
from about 0.degree. C. to about 100.degree. C., or from about
50.degree. C. to about 100.degree. C., or from about 60.degree. C.
to about 90.degree. C., or from about 75.degree. C. to about
85.degree. C. In an exemplary embodiment, the contacting of d)
occurs at a time of from about 1 sec to about 24 hours, or from
about 1 min to about 18 hours, or from about 30 min to about 12
hours, or from about 1 hour to about 6 hours, or from about 6 hours
to about 12 hours, or from about 6 hours to about 10 hours, or from
about 7 hours to about 9 hours. In an exemplary embodiment, the
second strong acid solution in d) is any one which dissolves the
product of c). In an exemplary embodiment, the second strong acid
solution is an H.sub.2SO.sub.4 solution. In an exemplary
embodiment, the second strong acid solution is an HNO.sub.3
solution. In an exemplary embodiment, the second strong acid
solution is an HI or HBr or HClO.sub.4 or HClO.sub.3 solution. In
an embodiment, a strong acid has a pH of less than 3, less than 2,
less than 1, or less than 0.5. In an exemplary embodiment, the
water used in the washing step for d) is deionized water. In an
exemplary embodiment, the contacting of d) occurs at a time of from
about 6 hours to about 12 hours and at a temperature of from about
60.degree. C. to about 100.degree. C. In an exemplary embodiment,
the contacting of d) occurs at a time of from about 6 hours to
about 10 hours and at a temperature of from about 70.degree. C. to
about 90.degree. C. In an exemplary embodiment, the contacting of
d) occurs at a time of from about 7 hours to about 9 hours and at a
temperature of from about 75.degree. C. to about 85.degree. C.
[0068] In an exemplary embodiment, the nitrogen-doped carbon
adsorbent is produced by a process further comprising e) heating
the product of d). In an exemplary embodiment, the heating in e)
occurs at a temperature of from about 0.degree. C. to about
1000.degree. C., or from about 0.degree. C. to about 1200.degree.
C., or from about 500.degree. C. to about 1200.degree. C., or from
about 500.degree. C. to about 1100.degree. C., or from about
100.degree. C. to about 1000.degree. C., or from about 300.degree.
C. to about 700.degree. C., or from about 400.degree. C. to about
700.degree. C., or from about 500.degree. C. to about 700.degree.
C., or from about 550.degree. C. to about 650.degree. C., or from
about 500.degree. C. to about 1000.degree. C., or from about
600.degree. C. to about 900.degree. C., or from about 600.degree.
C. to about 800.degree. C., or from about 600.degree. C. to about
700.degree. C., or from about 600.degree. C. to about 1000.degree.
C., or from about 700.degree. C. to about 1000.degree. C., or from
about 800.degree. C. to about 1000.degree. C., or from about
900.degree. C. to about 1000.degree. C., or from about 700.degree.
C. to about 900.degree. C., or from about 700.degree. C. to about
800.degree. C. In an exemplary embodiment, the heating in e) occurs
at a time of from about 1 sec to about 24 hours, or from about 1
min to about 18 hours, or from about 30 min to about 12 hours, or
from about 1 hour to about 6 hours, or from about 3 hours to about
5 hours, or from about 2 hours to about 4 hours, or from about 1
min to about 2 hours, or from about 30 min to about 90 min, or from
about 45 min to about 75 min, or about 60 min, or from about 5 min
to about 60 min, or from about 15 min to about 45 min, or about 30
min. In an exemplary embodiment, the heating of e) occurs in an
inert atmosphere. For example, the inert atmosphere does not
comprise oxygen. In one embodiment, the inert atmosphere is an
inert gas, such as nitrogen or argon. In an exemplary embodiment,
the heating of e) occurs in a nitrogen atmosphere.
[0069] In an exemplary embodiment, the nitrogen-doped carbon
adsorbent is produced by a process comprising: [0070] a) contacting
two nitrogen precursors and a suitable first metal-containing salt
in a first strong acid solution; [0071] b) contacting the product
of a) and an oxidant; [0072] c) heating the product of b); [0073]
d) contacting the product of c) with a second strong acid solution;
[0074] e) heating the product of d), thereby producing the
nitrogen-doped carbon adsorbent.
[0075] In an exemplary embodiment, the nitrogen-doped carbon
adsorbent is produced by a process comprising: [0076] a) contacting
two nitrogen precursors and a suitable first metal-containing salt
in a first strong acid solution, wherein the two nitrogen
precursors are aniline and cyanimide and the first metal-containing
salt is iron chloride or nickel chloride, and the first strong acid
solution is an HCl solution; [0077] b) contacting the product of a)
and (NH.sub.4).sub.2S.sub.2O.sub.8, thus forming an oxidized
product, and contacting said oxidized product with an aqueous
solution containing carbon black and a low molecular weight
alcohol; [0078] c) heating the product of b) to a first temperature
of from about 35.degree. C. to about 100.degree. C., and then to a
second temperature of from about 500.degree. C. to about
1000.degree. C.; [0079] d) contacting the product of c) with either
an H.sub.2SO.sub.4 solution or a HNO.sub.3 solution; [0080] e)
heating the product of d) from about 500.degree. C. to about
1000.degree. C., thereby producing the nitrogen-doped carbon
adsorbent.
[0081] In an exemplary embodiment, the nitrogen-doped carbon
adsorbent is produced by a process comprising: [0082] a) contacting
two nitrogen precursors and a suitable first metal-containing salt
in a first strong acid solution, wherein the two nitrogen
precursors are aniline and cyanimide and the first metal-containing
salt is iron chloride or nickel chloride, and the first strong acid
solution is an HCl solution; [0083] b) contacting the product of a)
and (NH.sub.4).sub.2S.sub.2O.sub.8, thus forming an oxidized
product, and contacting said oxidized product with an aqueous
solution containing Ketjenblack EC300J and/or MWV 295-R-03 and
isopropanol; [0084] c) heating the product of b) to a first
temperature of from about 35.degree. C. to about 100.degree. C.,
and then to a second temperature of from about 500.degree. C. to
about 1000.degree. C.; [0085] d) contacting the product of c) with
either an H.sub.2SO.sub.4 solution or a HNO.sub.3 solution; [0086]
e) heating the product of d) from about 500.degree. C. to about
1000.degree. C., thereby producing the nitrogen-doped carbon
adsorbent.
IIIc. Metal Nanoparticle-Deposited Nitrogen-Doped Carbon
Adsorbents
[0087] In an exemplary embodiment, the adsorbent comprises a metal
nanoparticle-deposited, nitrogen-doped carbon adsorbent. In an
exemplary embodiment, the adsorbent is a metal
nanoparticle-deposited, nitrogen-doped carbon adsorbent. In an
exemplary embodiment, the adsorbent is a gold
nanoparticle-deposited, nitrogen-doped carbon adsorbent. In an
exemplary embodiment, the adsorbent is prepared by a process
described herein. In an exemplary embodiment, the adsorbent is
prepared by a process found in the Examples. The adsorbents of the
present invention can have any adsorbent structure including
amorphous, crystalline, and mixtures thereof.
IIId. Synthesis of Metal Nanoparticle-Deposited Nitrogen-Doped
Carbon Adsorbents
[0088] In an exemplary embodiment, the metal
nanoparticle-deposited, nitrogen-doped carbon adsorbent is produced
by a process comprising: [0089] f) contacting a nitrogen-doped
carbon adsorbent with a second metal-containing salt; wherein said
f) does not comprise a reducing agent.
[0090] In an exemplary embodiment, the second metal in the suitable
second metal-containing salt is of periodic table Group 9-12. In an
exemplary embodiment, the second metal is selected from the group
consisting of Zn, Cu, Ag, Au, Hg, Pd, Pt, Co, and Ni. In an
exemplary embodiment, the second metal is Au. In an exemplary
embodiment, the second metal-containing salt is a gold chloride. In
an exemplary embodiment, the second metal-containing salt is gold
(III) chloride, gold (I) chloride, chlorotrimethylphosphine gold
(I), or a combination thereof. In another exemplary embodiment, the
second metal-containing salt is a gold nanoparticle. In another
exemplary the second metal-containing salt is a dodecanethiol
functionalized gold nanoparticles. In another exemplary embodiment,
the second metal-containing salt is generated by reaction from gold
precursors soluble in aqueous and alcoholic solvents In an
exemplary embodiment, the second metal-containing salt is
HAuCl.sub.4.3H.sub.2O.
[0091] In an exemplary embodiment, the contacting of f) occurs at a
temperature of from about 0.degree. C. to about 120.degree. C., or
from about 0.degree. C. to about 100.degree. C., or from about
10.degree. C. to about 100.degree. C., or from about 5.degree. C.
to about 50.degree. C., from about 10.degree. C. to about
30.degree. C., or at about room temperature. In an exemplary
embodiment, the contacting of f) occurs at a time of from about 1
sec to about 24 hours, or from about 1 min to about 18 hours, or
from about 30 min to about 12 hours, or from about 1 hour to about
6 hours, or from about 3 hours to about 5 hours, or from about 2
hours to about 4 hours, or from about 1 min to about 2 hours, or
from about 30 min to about 90 min, or from about 45 min to about 75
min, or about 60 min, or from about 5 min to about 60 min, or from
about 15 min to about 45 min, or about 30 min. In an exemplary
embodiment, the ratio of equivalents of the nitrogen-doped carbon
adsorbent to equivalents of the second metal-containing salt is
from about 1:1 to about 1:10, or from about 1000:1 to about 1:1, or
from about 100:1 to about 1:1, or from about 75:1 to about 25:1, or
from about 70:1 to about 30:1, or from about 65:1 to about 35:1, or
from about 60:1 to about 40:1, or from about 55:1 to about 45:1. In
an exemplary embodiment, f) does not comprise a reducing agent such
as a borohydride, such as sodium borohydride.
[0092] In an exemplary embodiment, the metal
nanoparticle-deposited, nitrogen-doped carbon adsorbent is produced
by a process comprising: [0093] f) contacting a nitrogen-doped
carbon adsorbent with a second metal-containing salt, forming a
product which is filtered and dried; wherein said f) does not
comprise a reducing agent, such as a borohydride, such as sodium
borohydride.
IV. The Method of Removing Sulfur Compounds from a Fuel Feed
Stream
[0094] In one embodiment, the invention relates to a method for
removing sulfur compounds from a hydrocarbon feed stream. The
method comprises the steps of: 1) providing a first hydrocarbon
feed stream, which is contaminated with sulfur compounds; and 2)
passing the first hydrocarbon feed stream through a desulfurization
system comprising a metal nanoparticle deposited nitrogen-doped
carbon adsorbent to produce a second hydrocarbon feed stream which
has substantially less sulfur compounds than the first hydrocarbon
feed stream.
[0095] In some embodiments, 2) has a liquid hourly space velocity
(LHSV) of about 0.01 to about 30. In some embodiments, 2) has a
LHSV of about 0.1 to about 20. In some embodiments, 2) has a LHSV
of about 0.3 to about 10. In some embodiments, 2) has a LHSV of
about 0.5 to about 5. In some embodiments, 2) has a temperature of
about 0.degree. C. to about 200.degree. C. In some embodiment, 2)
has a temperature of about 10.degree. C. to about 100.degree. C. In
some embodiment, 2) has a temperature of about 20.degree. C. to
about 50.degree. C. In some embodiments, 2) has a pressure of about
0 to 20,000 kPa (0 to about 200 bar). In some embodiments, 2) has a
pressure of about 0 to 2,000 kPa (0 to about 20 bar). In some
embodiments, 2) has a pressure of about 0 to 200 kPa (0 to about 2
bar).
[0096] In some embodiments, the method further comprises: 3)
desulfurizing and regenerating the metal nanoparticle deposited
nitrogen-doped carbon adsorbent of 2) by treatment with a solvent.
In some embodiments, the solvent is selected from the group
consisting of aromatic solvents, oxygen-containing polar organic
solvents, and nitrogen-containing polar organic solvents and
mixture thereof.
[0097] In some embodiments, the solvent is an organic solvent
selected from the group consisting of acetic acid, acetone,
acetonitrile, benzene, benzonitrile, benzenethiol, benzyl alcohol,
1-butanol, 2-butanol, n-butanol, 2-butaone, 2-t-butyl alcohol,
carbon tetrachloride, chlorobenzene, 1,2-dichlorobenzene,
1,2-difluorobenzene, chloroform, cyclohexane, 1,2-dichloroethane,
diethylene glycol, diethyl ether, dimethylacetamide (DMAc),
dimethyl ether diglyme (diethylene glycol dimethyl ether),
1-diethylaminoethanol, diethylformamide, 1,2-dimethoxy-ethane
(glyme, DME), dimethylformamide (DMF), dimethyl sulfoxide (DMSO),
dioxane, 1,4-dioxane, ethanol, ethyl acetate, ethylene dichloride,
ethylene glycol, formic acid, glycerin, heptane,
hexamethylphosphoramide (HMPA), hexamethylphosphorous triamide
(HMPT), hexanes, isopropanol, methanol, methyl t-butyl ether
(MTBE), methylene chloride, N-methyl-2-pyrrolidinone (NMP),
nitromethane, pentane, petroleum ether (ligroine), 1-propanol,
2-propanol, n-propanol, pyridine, tetrahydrofuran (THF), toluene,
triethyl amine, o-xylene, m-xylene, and p-xylene.
[0098] In some embodiments, the solvent is an aromatic solvent
selected from the group consisting of benzene, benzonitrile,
benzenethiol, benzyl alcohol, chlorobenzene, 1,2-dichlorobenzene,
1,2-difluorobenzene, hexafluorobenzene, mesitylene, nitrobenzene,
phenol, pyridine, tetralin, toluene, 1,2,4-trichlorobenzene,
trifluorotoluene, and xylene. Examples of nitrogen-containing polar
organic solvents include acetonitrile, benzonitrile,
dimethylformamide (DMF), diethylformamide, 1-diethylaminoethanol,
dimethylacetamide (DMAc), hexamethylphosphorous triamide (HMPT),
hexamethylphosphoramide (HMPA), N-methyl-2-pyrrolidinone (NMP),
nitromethane, pyridine, and triethyl amine.
[0099] In some embodiments, the solvent is an oxygen-containing
polar organic solvent selected from the group consisting of acetic
acid, acetone, benzyl alcohol, 1-butanol, 2-butanol, n-butanol,
2-butaone, 2-t-butyl alcohol, diethylene glycol, diethyl ether,
dimethylacetamide (DMAc), dimethyl ether diglyme (diethylene glycol
dimethyl ether), 1-diethylaminoethanol, diethylformamide,
1,2-dimethoxy-ethane (glyme, DME), dimethylformamide (DMF),
dimethyl sulfoxide (DMSO), dioxane, 1,4-dioxane, ethanol, ethyl
acetate, ethylene glycol, formic acid, glycerin,
hexamethylphosphoramide (HMPA), hexamethylphosphorous triamide
(HMPT), isopropanol, methanol, methyl t-butyl ether (MTBE),
N-methyl-2-pyrrolidinone (NMP), 1-propanol, 2-propanol, n-propanol,
and tetrahydrofuran (THF).
[0100] In some embodiments, 3) has a liquid hourly space velocity
(LHSV) of about 0.5 to about 50. In some embodiments, 3) has a LHSV
of about 1 to about 30. In some embodiments, 3) has a LHSV of about
1 to about 20. In some embodiments, 3) has a LHSV of about 1 to
about 10. In some embodiments, 3) has a LHSV of about 0.5 to about
5. In some embodiments, 3) has a temperature of about 0.degree. C.
to about 200.degree. C. In some embodiment, 3) has a temperature of
about 10.degree. C. to about 100.degree. C. In some embodiment, 3)
has a temperature of about 20.degree. C. to about 50.degree. C. In
some embodiments, 3) has a pressure of about 0 to 20,000 kPa (0 to
about 200 bar). In some embodiments, 3) has a pressure of about 0
to 2,000 kPa (0 to about 20 bar). In some embodiments, 3) has a
pressure of about 0 to 200 kPa (0 to about 2 bar).
[0101] In some embodiments, the metal nanoparticle deposited
nitrogen-doped carbon adsorbent regeneration of 3) is able to
restore-up to about 30% of the metal nanoparticle deposited
nitrogen-doped carbon adsorbent's initial adsorbent desulfurization
capacity measured in method 2) under the same method conditions. In
some embodiments, the metal nanoparticle deposited nitrogen-doped
carbon adsorbent regeneration of 3) is able to restore to up to
about 40% of the metal nanoparticle deposited nitrogen-doped carbon
adsorbent's initial adsorbent desulfurization capacity. In some
embodiments, the metal nanoparticle deposited nitrogen-doped carbon
adsorbent regeneration of 3) is able to restore to up to about 50%
of the metal nanoparticle deposited nitrogen-doped carbon
adsorbent's initial adsorbent desulfurization capacity. In some
embodiments, the metal nanoparticle deposited nitrogen-doped carbon
adsorbent regeneration of 3) is able to restore to up to about 60%
of the metal nanoparticle deposited nitrogen-doped carbon
adsorbent's initial adsorbent desulfurization capacity. In some
embodiments, the metal nanoparticle deposited nitrogen-doped carbon
adsorbent regeneration of 3) is able to restore to up to about 65%
of the metal nanoparticle deposited nitrogen-doped carbon
adsorbent's initial adsorbent desulfurization capacity. In some
embodiments, the metal nanoparticle deposited nitrogen-doped carbon
adsorbent regeneration of 3) is able to restore to up to about 70%
of the metal nanoparticle deposited nitrogen-doped carbon
adsorbent's initial adsorbent desulfurization capacity. In some
embodiments, the metal nanoparticle deposited nitrogen-doped carbon
adsorbent regeneration of 3) is able to restore to up to about 75%
of the metal nanoparticle deposited nitrogen-doped carbon
adsorbent's initial adsorbent desulfurization capacity. In some
embodiments, the metal nanoparticle deposited nitrogen-doped carbon
adsorbent regeneration of 3) is able to restore to up to about 80%
of the metal nanoparticle deposited nitrogen-doped carbon
adsorbent's initial adsorbent desulfurization capacity. In some
embodiments, the metal nanoparticle deposited nitrogen-doped carbon
adsorbent regeneration of 3) is able to restore to up to about 90%
of the metal nanoparticle deposited nitrogen-doped carbon
adsorbent's initial adsorbent desulfurization capacity. In some
embodiments, the metal nanoparticle deposited nitrogen-doped carbon
adsorbent regeneration of 3) is able to restore to up to about 99%
of the metal nanoparticle deposited nitrogen-doped carbon
adsorbent's initial adsorbent desulfurization capacity.
[0102] In some embodiments, the nanoparticle deposited
nitrogen-doped carbon adsorbent regeneration of 3) is regenerated
multiple time with capacity restored from about 30% to about 99%
measured in method b) under the same method conditions.
[0103] In some embodiments, the metal nanoparticle deposited
nitrogen-doped carbon adsorbent comprises a first metal selected
from the group consisting of metals of periodic table Period 4. In
some embodiments, the metal nanoparticle deposited nitrogen-doped
carbon adsorbent comprises a first metal selected from the group
consisting of Mn, Fe, Co, Ni, Cu, and Zn. In some embodiments, the
first metal is Fe or Ni.
[0104] In some embodiments, the metal nanoparticle deposited
nitrogen-doped carbon adsorbent comprises a second metal selected
the group consisting of metals of periodic table Group 9-12. In
some embodiments, the metal nanoparticle deposited nitrogen-doped
carbon adsorbent comprises a second metal selected from the group
consisting of Zn, Cu, Ag, Au, Hg, Pd, Pt, Co, and Ni. In some
embodiments, the second metal contained in the metal nanoparticle
deposited nitrogen-doped carbon adsorbent is Au.
[0105] In some embodiments, the second metal contained in the metal
nanoparticle deposited nitrogen-doped carbon adsorbent is present
in an amount of about 0.01% to about 30% by weight. In some
embodiments, the second metal contained in the metal nanoparticle
deposited nitrogen-doped carbon adsorbent is present in an amount
of about 0.1% to about 10% by weight. In some embodiments, the
second metal contained in the metal nanoparticle deposited
nitrogen-doped carbon adsorbent is present in an amount of about
0.3% to about 3% by weight.
[0106] In some embodiments, the metal nanoparticle deposited
nitrogen-doped carbon adsorbent contains about 0.5% to about 30% by
weight nitrogen. In some embodiments, the metal nanoparticle
deposited nitrogen-doped carbon adsorbent contains about 1% to
about 20% by weight nitrogen. In some embodiments, the metal
nanoparticle deposited nitrogen-doped carbon adsorbent contains
about 4% to about 10% by weight nitrogen.
[0107] In some embodiments, the metal nanoparticle deposited
nitrogen-doped carbon adsorbent contains about 0.5% to about 30% by
weight oxygen. In some embodiments, the metal nanoparticle
deposited nitrogen-doped carbon adsorbent contains about 2% to
about 20% by weight oxygen. In some embodiments, the metal
nanoparticle deposited nitrogen-doped carbon adsorbent contains
about 4% to about 10% by weight oxygen.
[0108] In some embodiments, the sulfur compounds are selected from
compounds having a boiling point within or about the boiling point
range of liquid fuel having an initial boiling point above
80.degree. C., or preferably above 125.degree. C. In some
embodiments, the sulfur compounds are carbonyl sulfide, hydrogen
sulfide, thiophene, disulfides, sulfoxides, mercaptan, higher
molecular weight organic sulfur-containing compounds, and
derivatives thereof. In some embodiments, the sulfur compounds are
thiophene and thiophene derivatives. In some embodiments, the
sulfur compounds are alkyl substituted benzothiophene and
dibenzothiophene derivatives. In some embodiments, the sulfur
compounds are higher molecular weight organic sulfur-containing
compounds selected from the group consisting of at least 2-ring
polycyclic aromatics with at least one carbon atom in the aromatic
ring being replaced by one S atom. In some embodiments, the sulfur
compounds comprise thiophene, benzothiophene, dibenzothiophene and
their derivatives. In some embodiments, the first hydrocarbon feed
stream contains aromatics with a similar aromaticity or same ring
number as the thiophene and/or thiophene derivatives. In some
embodiments, the thiophene derivatives are substituted and
unsubstituted thiophene derivatives. In some embodiments, the
thiophene derivatives are benzothiophene and dibenzothiophene
derivatives optionally substituted with 1-4 groups each
independently selected from the group consisting of linear or
branched alkyl, heteroalkyl, cycloalkyl, heterocycloalkyl, aryl,
heteroaryl, and naphthenic and hetero-naphthenic derivatives. In
some embodiments, the thiophene derivatives are mono or di alkyl
substituted benzothiophene and dibenzothiophenes. In some
embodiments, the thiophene derivatives are 4,6-dialkyl
dibenzothiophenes. In some embodiments, the thiophene derivative is
benzothiophene, dibenzothiophene (DBT) or
4,6-dimethyldibenzothiophene (DMDBT). In some embodiments, the
thiophene derivative is 4,6-dimethyldibenzothiophene (DMDBT).
[0109] In some embodiments, the sulfur compounds are present in the
first hydrocarbon feed stream in an amount of about 1 ppm to about
500 ppm. In some embodiments, the sulfur compounds are present in
the first hydrocarbon feed stream in an amount of about 5 ppm to
about 200 ppm, In some embodiments, the sulfur compounds are
present in the first hydrocarbon feed stream in an amount of about
10 ppm to about 100 ppm. In some embodiments, the sulfur compounds
are present in the first hydrocarbon feed stream in an amount of
about 10 ppm to about 50 ppm.
[0110] In some embodiments, the sulfur compounds are present in the
second hydrocarbon feed stream in an amount of less than about 500
ppm. In some embodiments, the sulfur compounds are present in the
second hydrocarbon feed stream in an amount of less than about 100
ppm. In some embodiments, the sulfur compounds are present in the
second hydrocarbon feed stream in an amount of less than about 50
ppm. In some embodiments, the sulfur compounds are present in the
second hydrocarbon feed stream in an amount of less than about 10
ppm. In some embodiments, the sulfur compounds are present in the
second hydrocarbon feed stream in an amount of less than about 2
ppm. In some embodiments, the sulfur compounds are present in the
second hydrocarbon feed stream in an amount of less than about 1
ppm. In some embodiments, the second hydrocarbon feed stream
contains about 70% to about 99.9% by weight less sulfur compounds
than the first hydrocarbon feed stream. In some embodiments, the
second hydrocarbon feed stream contains about 90% to about 99.9% by
weight less sulfur compounds than the first hydrocarbon feed
stream.
[0111] In some embodiments, the hydrocarbon feed stream is a liquid
fuel stream. In some embodiments, the hydrocarbon feed stream
hydrocarbon feed stream is selected from the group consisting of
diesel fuel, jet fuel, gasoline, kerosene, compressed natural gas,
liquefied petroleum gas (LPG), ethanol, methanol, and butanol. In
some embodiments, the hydrocarbon feed stream is diesel fuel or jet
fuel.
[0112] In some embodiments, the present invention provides a method
for removing thiophene and thiophene derivatives from a hydrocarbon
feed stream comprising: a) providing a first hydrocarbon feed
stream, which is contaminated with thiophene and thiophene
derivatives; and b) passing the first hydrocarbon feed stream
through a desulfurization system comprising a gold nanoparticle
deposited nitrogen-doped carbon adsorbent to produce a second
hydrocarbon feed stream which has substantially less thiophene and
thiophene derivatives than the first hydrocarbon feed stream,
wherein thiophene and thiophene derivatives are present in the
first hydrocarbon feed stream in an amount of about 1 ppm to about
100 ppm and wherein the gold nanoparticle deposited nitrogen-doped
carbon contains gold in an amount of about 0.1% to about 5% by
weight, nitrogen in amount of about 1% to about 20% by weight
nitrogen, and oxygen in an amount of about 4% to about 10% by
weight.
[0113] In some embodiments, the present invention provides a method
for removing benzothiophene, dibenzothiophene (DBT) and/or
4,6-dimethyldibenzothiophene (DMDBT) from a liquid fuel feed stream
comprising: a) providing a first liquid fuel stream, which is
contaminated with benzothiophene, DBT and/or DMDBT; and b) passing
the first liquid fuel stream through a desulfurization system
comprising a gold nanoparticle deposited nitrogen-doped carbon
adsorbent to produce a second liquid fuel stream which has less
than 1 ppm of benzothiophene, DBT and/or DMDBT, wherein
benzothiophene, DBT and/or DMDBT are present in the first liquid
fuel stream in an amount of about 1 ppm to about 50 ppm and wherein
the gold nanoparticle deposited nitrogen-doped carbon contains gold
in an amount of about 0.1% to about 5% by weight, nitrogen in
amount of about 1% to about 20% by weight nitrogen, and oxygen in
an amount of about 4% to about 10% by weight.
[0114] In some embodiments, the present invention provides a method
for removing benzothiophene, DBT and/or
4,6-dimethyldibenzothiophene (DMDBT) from a liquid fuel feed stream
comprising: a) providing a first liquid fuel stream, which is
contaminated with benzothiophene, DBT and/or DMDBT; and b) passing
the first liquid fuel stream through a desulfurization system
comprising a gold nanoparticle deposited nitrogen-doped carbon
adsorbent to produce a second liquid fuel stream which has about
90% to about 99.9% by weight less sulfur compounds than the first
liquid fuel stream, wherein benzothiophene, DBT and/or DMDBT are
present in the first liquid fuel stream in an amount of about 1 ppm
to about 50 ppm and wherein the gold nanoparticle deposited
nitrogen-doped carbon contains gold in an amount of about 0.1% to
about 3% by weight, nitrogen in amount of about 1% to about 20% by
weight nitrogen, and oxygen in an amount of about 4% to about 10%
by weight.
[0115] In some embodiments, the present invention provides a method
for removing thiophene, benzothiophene, dibenzothiophene and their
derivatives from a liquid fuel feed stream comprising: a) providing
a first liquid fuel stream, which is contaminated with thiophene,
benzothiophene, dibenzothiophene and their derivatives; and b)
contacting the first liquid fuel stream with a desulfurization
adsorbent comprising a gold nanoparticle deposited nitrogen-doped
carbon in a batch container for a period of time from 1 minute to
48 hours with agitation. Separation of the adsorbent from the
mixture by filtration to obtain a second liquid fuel stream which
has about 30% to about 99.9% by weight less sulfur compounds than
the first liquid fuel stream, wherein thiophene, benzothiophene,
dibenzothiophene and their derivatives are present in the first
liquid fuel stream in an amount of about 1 ppm to about 100 ppm and
wherein the gold nanoparticle deposited nitrogen-doped carbon
contains gold in an amount of about 0.1% to about 3% by weight,
nitrogen in amount of about 1% to about 20% by weight nitrogen, and
oxygen in an amount of about 1% to about 10% by weight.
EXAMPLES
[0116] The following Examples illustrate the synthesis and
properties of representative adsorbents of the invention. These
examples are not intended, nor are they to be construed, as
limiting the scope of the invention. It will be clear that the
invention may be practiced otherwise than as particularly described
herein. Numerous modifications and variations of the invention are
possible in view of the teachings herein and, therefore, are within
the scope of the invention. Suitable test methods for determining
sulfur in liquid hydrocarbons is ASTM D5623-94 (R 2014), Standard
Test Method for Sulfur Compounds in Light Petroleum Liquids by Gas
Chromatography and Sulfur Selective Detection. This test method is
applicable to the determination of individual sulfur species at
levels of 0.1 to 100 wt ppm. An Intertek Total S Analyzer and an
Agilent GC--Sulfur Chemiluminescence Detector (SCD) were used for
determination of sulfur speciation and concentration.
PANI-Based Adsorbent Synthesis: Sample A
[0117] 2.5 ml aniline was added into 500 ml 2.0 M HCl solution
while stirring by a magnetic bar at room temperature on a hot
plate. As an iron source, 10.0 g FeCl.sub.3 was added into the
aniline solution. After dissolving the FeCl.sub.3, 5.0 g of
(NH.sub.4).sub.2S.sub.2O.sub.8 (ammonium persulfate, APS) as
oxidant was added into the solution to polymerize aniline. The
solution was stirred at room temperature for 4 hours to allow full
polymerization of aniline. 0.4 g of carbon (Ketjenblack EC300J) was
ultrasonically dispersed for 3 hr in 120 ml of (water (100
ml)+isopropanol alcohol (20 ml) solution in advance, and mixed with
the above dispersion containing polyaniline (PANI). The temperature
of the hot plate was increased up to 80.degree. C. and the solution
was dried while stirring until it became completely dried. The
subsequent heat-treatment for the obtained material was performed
at 900.degree. C. in nitrogen atmosphere for 1 hour. The
heat-treated powder was ground by a mortar, and the obtained powder
was subsequently acid-leached in 300 ml 0.5 M H.sub.2SO.sub.4 at
80.degree. C. for 8 hours, and fully washed by an ample amount of
deionized (DI) water. After drying at 90.degree. C. in vacuum oven
overnight, this dried powder was heat-treated again at 600.degree.
C. in nitrogen atmosphere for 30 minutes to get the final
adsorbent.
PANI-Based Adsorbent Synthesis: Sample B
[0118] 2.5 ml aniline was added into 500 ml 2.0 M HCl solution
while stirring by a magnetic bar at room temperature on a hot
plate. As an iron source, 10.0 g FeCl.sub.3 was added into the
aniline solution. After dissolving the FeCl.sub.3, 5.0 g of
(NH.sub.4).sub.2S.sub.2O.sub.8 (ammonium persulfate, APS) as
oxidant was added into the solution to polymerize aniline. The
solution was stirred at room temperature for 4 hours to allow full
polymerization of aniline. 0.4 g of carbon (Ketjenblack EC300J) was
ultrasonically dispersed for 3 hr in 120 ml of (water (100
ml)+isopropanol alcohol (20 ml) solution in advance, and mixed with
the above dispersion containing polyaniline (PANI). The temperature
of the hot plate was increased up to 80.degree. C., and the
solution was dried while stirring until it became completely dried.
The subsequent heat-treatment for the obtained material was
performed at 800.degree. C. in nitrogen atmosphere for 1 hour. The
heat-treated powder was ground by a mortar, and the obtained powder
was subsequently acid-leached in 300 ml 0.5 M H.sub.2SO.sub.4 at
80.degree. C. for 8 hours, and fully washed by an ample amount of
DI water. After drying at 90.degree. C. in vacuum oven overnight,
this dried powder was heat-treated again at 600.degree. C. in
nitrogen atmosphere for 30 minutes to get the final adsorbent.
PANI-Based Adsorbent Synthesis: Sample C
[0119] 2.5 ml aniline was added into 500 ml 2.0 M HCl solution
while stirring by a magnetic bar at room temperature on a hot
plate. As an iron source, 10.0 g FeCl.sub.3 was added into the
aniline solution. After dissolving the FeCl.sub.3, 5.0 g of
(NH.sub.4).sub.2S.sub.2O.sub.8 (ammonium persulfate, APS) as
oxidant was added into the solution to polymerize aniline. The
solution was stirred at room temperature for 4 hours to allow full
polymerization of aniline. 0.4 g of carbon (Ketjenblack EC300J) was
ultrasonically dispersed for 3 hr in 120 ml of (water (100
ml)+isopropanol alcohol (20 ml) solution in advance, and mixed with
the above dispersion containing polyaniline (PANI). The temperature
of the hot plate was increased up to 80.degree. C., and the
solution was dried while stirring until it became completely dried.
The subsequent heat-treatment for the obtained material was
performed at 700.degree. C. in nitrogen atmosphere for 1 hour. The
heat-treated powder was ground by a mortar, and the obtained powder
was subsequently acid-leached in 300 ml 0.5 M H.sub.2SO.sub.4 at
80.degree. C. for 8 hours, and fully washed by an ample amount of
DI water. After drying at 90.degree. C. in vacuum oven overnight,
this dried powder was heat-treated again at 600.degree. C. in
nitrogen atmosphere for 30 minutes to get the final adsorbent.
PANI-Based Adsorbent Synthesis: Sample E
[0120] 2.5 ml aniline was added into 500 ml 2.0 M HCl solution
while stirring by a magnetic bar at room temperature on a hot
plate. As an iron source, 10.0 g FeCl.sub.3 was added into the
aniline solution. After dissolving the FeCl.sub.3, 6 ml of 30%
H.sub.2O.sub.2 as oxidant was added into the solution to polymerize
aniline. The solution was stirred at room temperature for 4 hours
to allow full polymerization of aniline. 0.4 g of carbon
(Ketjenblack EC300J) was ultrasonically dispersed for 3 hr in 120
ml of (water (100 ml)+isopropanol alcohol (20 ml) solution in
advance, and mixed with the above dispersion containing polyaniline
(PANI). The temperature of the hot plate was increased up to
80.degree. C., and the solution was dried while stirring until it
became completely dried. The subsequent heat-treatment for the
obtained material was performed at 900.degree. C. in nitrogen
atmosphere for 1 hour. The heat-treated powder was ground by a
mortar, and the obtained powder was subsequently acid-leached in
300 ml 0.5 M H.sub.2SO.sub.4 at 80.degree. C. for 8 hours, and
fully washed by an ample amount of DI water. After drying at
90.degree. C. in vacuum oven overnight, this dried powder was
heat-treated again at 600.degree. C. in nitrogen atmosphere for 30
minutes to get the final adsorbent.
PANI-Based Adsorbent Synthesis: Sample F
[0121] 2.5 ml aniline was added into 500 ml 2.0 M HCl solution
while stirring by a magnetic bar at room temperature on a hot
plate. As an iron source, 10.0 g FeCl.sub.3 was added into the
aniline solution. After dissolving the FeCl.sub.3, 5.0 g of
(NH.sub.4).sub.2S.sub.2O.sub.8 (ammonium persulfate, APS) as
oxidant was added into the solution to polymerize aniline. The
solution was stirred at room temperature for 4 hours to allow full
polymerization of aniline. 0.4 g of carbon (Ketjenblack EC300J) was
ultrasonically dispersed for 3 hr in 120 ml of (water (100
ml)+isopropanol alcohol (20 ml) solution in advance, and mixed with
the above dispersion containing polyaniline (PANI). The temperature
of the hot plate was increased up to 80.degree. C., and the
solution was dried while stirring until it became completely dried.
The subsequent heat-treatment for the obtained material was
performed at 750.degree. C. in nitrogen atmosphere for 1 hour. The
heat-treated powder was ground by a mortar, and the obtained powder
was subsequently acid-leached in 300 ml 0.5 M H.sub.2SO.sub.4 at
80.degree. C. for 8 hours, and fully washed by an ample amount of
DI water. After drying at 90.degree. C. in vacuum oven overnight,
this dried powder was heat-treated again at 600.degree. C. in
nitrogen atmosphere for 30 minutes to get the final adsorbent.
PANI-Based Adsorbent Synthesis: Sample G
[0122] 2.5 ml aniline was added into 500 ml 2.0 M HCl solution
while stirring by a magnetic bar at room temperature on a hot
plate. As an iron source, 10.0 g FeCl.sub.3 was added into the
aniline solution. After dissolving the FeCl.sub.3, 5.0 g of
(NH.sub.4).sub.2S.sub.2O.sub.8 (ammonium persulfate, APS) as
oxidant was added into the solution to polymerize aniline. The
solution was stirred at room temperature for 4 hours to allow full
polymerization of aniline. 0.4 g of carbon (Ketjenblack EC300J) was
ultrasonically dispersed for 3 hr in 120 ml of (water (100
ml)+isopropanol alcohol (20 ml) solution in advance, and mixed with
the above dispersion containing polyaniline (PANI). The temperature
of the hot plate was increased up to 80.degree. C., and the
solution was dried while stirring until it became completely dried.
The subsequent heat-treatment for the obtained material was
performed at 850.degree. C. in nitrogen atmosphere for 1 hour. The
heat-treated powder was ground by a mortar, and the obtained powder
was subsequently acid-leached in 300 ml 0.5 M H.sub.2SO.sub.4 at
80.degree. C. for 8 hours, and fully washed by ample of DI water.
After drying at 90.degree. C. in vacuum oven overnight, this dried
powder was heat-treated again at 600.degree. C. in nitrogen
atmosphere for 30 minutes to get the final adsorbent. Cyanamide
(CM)+Polyaniline (PANI)-based adsorbent synthesis: Sample D
[0123] 3.0 ml aniline was added into 500 ml 2.0 M HCl solution
while stirring by a magnetic bar at room temperature on a hot
plate. 7.0 g of cyanamide (CM) was added into this aniline
solution. As an iron source, 10.0 g FeCl.sub.3 was added into the
(aniline+cyanamide) solution. After dissolving the FeCl.sub.3, 5.0
g of (NH.sub.4).sub.2S.sub.2O.sub.8 (ammonium persulfate, APS) as
oxidant was added into the solution to polymerize aniline. The
solution was stirred at room temperature for 4 hours to allow full
polymerization of aniline. 0.4 g of carbon (Ketjenblack EC300J) was
ultrasonically dispersed for 3 hr in 120 ml of (water (100
ml)+isopropanol alcohol (20 ml) solution in advance, and mixed with
the above dispersion containing cyanamide (CM) and polyaniline
(PANI). The temperature of the hot plate was increased up to
80.degree. C., and the solution was dried while stirring until it
became a tar-like state. The subsequent heat-treatment for the
obtained material was performed at 900.degree. C. in nitrogen
atmosphere for 1 hour. The heat-treated powder was ground by a
mortar, and the obtained powder was subsequently acid-leached in
300 ml 0.5 M H.sub.2SO.sub.4 at 80.degree. C. for 8 hours, and
fully washed by an ample amount of DI water. After drying at
90.degree. C. in vacuum oven overnight, this dried powder was
heat-treated again at 600.degree. C. in nitrogen atmosphere for 30
minutes to get the final adsorbent.
(CM+PANI)-Based Adsorbent Synthesis: Sample H
[0124] 3.0 ml aniline was added into 500 ml 2.0 M HCl solution
while stirring by a magnetic bar at room temperature on a hot
plate. 7.0 g of cyanamide (CM) was added into this aniline
solution. As an iron source, 14.7 g NiCl.sub.3.6H.sub.2O was added
into the (aniline+cyanamide) solution. After dissolving the
NiCl.sub.3.6H.sub.2O, 5.0 g of (NH.sub.4).sub.2S.sub.2O.sub.8
(ammonium persulfate, APS) as oxidant was added into the solution
to polymerize aniline. The solution was stirred at room temperature
for 4 hours to allow full polymerization of aniline. 0.4 g of
carbon (Ketjenblack EC300J) was ultrasonically dispersed for 3 hr
in 120 ml of (water (100 ml)+isopropanol alcohol (20 ml) solution
in advance, and mixed with the above dispersion containing
cyanamide (CM) and polyaniline (PANI). The temperature of the hot
plate was increased up to 80.degree. C., and the solution was dried
while stirring until it became a tar-like state. The subsequent
heat-treatment for the obtained material was performed at
900.degree. C. in nitrogen atmosphere for 1 hour. The heat-treated
powder was ground by a mortar, and the obtained powder was
subsequently acid-leached in 300 ml 0.5 M H.sub.2SO.sub.4 at
80.degree. C. for 8 hours, and fully washed by an ample amount of
deionized (DI) water. After drying at 90.degree. C. in vacuum oven
overnight, this dried powder was heat-treated again at 600.degree.
C. in nitrogen atmosphere for 30 minutes to get the final
adsorbent.
(CM+PANI)-Based Adsorbent Synthesis: Sample I
[0125] 3.0 ml aniline was added into 500 ml 2.0 M HCl solution
while stirring by a magnetic bar at room temperature on a hot
plate. 7.0 g of cyanamide (CM) was added into this aniline
solution. As an iron source, 14.7 g NiCl.sub.3.6H.sub.2O was added
into the (aniline+cyanamide) solution. After dissolving the
NiCl.sub.3.6H.sub.2O, 5.0 g of (NH.sub.4).sub.2S.sub.2O.sub.8
(ammonium persulfate, APS) as oxidant was added into the solution
to polymerize aniline. The solution was stirred at room temperature
for 4 hours to allow full polymerization of aniline. 0.4 g of
carbon (Ketjenblack EC300J) was ultrasonically dispersed for 3 hr
in 120 ml of (water (100 ml)+isopropanol alcohol (20 ml) solution
in advance, and mixed with the above dispersion containing
cyanamide and polyaniline (PANI). The temperature of the hot plate
was increased up to 80.degree. C., and the solution was dried while
stirring until it became a tar-like state. The subsequent
heat-treatment for the obtained material was performed at
900.degree. C. in nitrogen atmosphere for 1 hour. The heat-treated
powder was ground by a mortar, and the obtained powder was
subsequently acid-leached in 300 ml 3.0 M HNO.sub.3 at 80.degree.
C. for 8 hours, and fully washed by an ample amount of DI water.
After drying at 90.degree. C. in vacuum oven overnight, this dried
powder was heat-treated again at 600.degree. C. in nitrogen
atmosphere for 30 minutes to get the final adsorbent.
(CM+PANI)-Based Adsorbent Synthesis: Sample J
[0126] 3.0 ml aniline was added into 500 ml 2.0 M HCl solution
while stirring by a magnetic bar at room temperature on a hot
plate. 7.0 g of cyanamide (CM) was added into this aniline
solution. As an iron source, 10.0 g FeCl.sub.3 was added into the
(aniline+cyanamide) solution. After dissolving the FeCl.sub.3, 5.0
g of (NH.sub.4).sub.2S.sub.2O.sub.8 (ammonium persulfate, APS) as
oxidant was added into the solution to polymerize aniline. The
solution was stirred at room temperature for 4 hours to allow full
polymerization of aniline. 0.4 g of carbon (Ketjenblack EC300J) was
ultrasonically dispersed for 3 hr in 120 ml of (water (100
ml)+isopropanol alcohol (20 ml) solution in advance, and mixed with
the above dispersion containing cyanamide (CM) and polyaniline
(PANI). The temperature of the hot plate was increased up to
80.degree. C., and the solution was dried while stirring until it
became a tar-like state. The subsequent heat-treatment for the
obtained material was performed at 800.degree. C. in nitrogen
atmosphere for 30 minutes. The heat-treated powder was ground by a
mortar, and the obtained powder was subsequently acid-leached in
300 ml 0.5 M H.sub.2SO.sub.4 at 80.degree. C. for 8 hours, and
fully washed by ample of DI water. After drying at 90.degree. C. in
vacuum oven overnight, this dried powder was heat-treated again at
500.degree. C. in nitrogen atmosphere for 30 minutes to get the
final adsorbent.
(CM+PANI)-Based Adsorbent Synthesis: Sample L
[0127] Au deposition was done on Sample K with a reducing agent,
sodium borohydride (NaBH.sub.4), to make 1 wt % Au deposition. 2.5
g of Sample T was sonicated in 500 ml DI water for 1 hour. 0.0505 g
of HAuCl.sub.4.3H.sub.2O was dissolved in 100 ml DI water. Both of
these solutions were mixed together and stirred for 2 hours. 0.2 g
of NaBH.sub.4 was added to the mixture and stirred for an
additional 2 hours. The resulting stirred mixture was filtered
using a 0.45 micrometer membrane filter and dried in a vacuum oven
at 90.degree. C. overnight. Sample M
[0128] WV-B-1500 was modified by ammonia (NH.sub.3) at 900.degree.
C. for 20 minutes. Sample N
[0129] WV-B-1500 was modified by 3.0 M HNO.sub.3 at 80.degree. C.
for 8 hours and ammonia (NH.sub.3) at 900.degree. C. for 20
minutes.
(CM+PANI)-Based Adsorbent Synthesis: Sample P
[0130] 3.0 ml aniline was added into 500 ml 2.0 M HCl solution
while stirring by a magnetic bar at room temperature on a hot
plate. 7.0 g of cyanamide (CM) was added into this aniline
solution. As an iron source, 10.0 g FeCl.sub.3 was added into the
(aniline+cyanamide) solution. After dissolving the FeCl.sub.3, 5.0
g of (NH.sub.4).sub.2S.sub.2O.sub.8 (ammonium persulfate, APS) as
oxidant was added into the solution to polymerize aniline. The
solution was stirred at room temperature for 4 hours to allow full
polymerization of aniline. The temperature of the hot plate was
increased up to 80.degree. C., and the solution was dried while
stirring until it became a tar-like state. The subsequent
heat-treatment for the obtained material was performed at
800.degree. C. in nitrogen atmosphere for 30 minutes. The
heat-treated powder was ground by a mortar, and the obtained powder
was subsequently acid-leached in 300 ml 0.5 M H.sub.2SO.sub.4 at
80.degree. C. for 8 hours, and fully washed by an ample amount of
DI water. After drying at 90.degree. C. in vacuum oven overnight,
this dried powder was heat-treated again at 500.degree. C. in
nitrogen atmosphere for 30 minutes to get the final adsorbent.
(CM+PANI)-Based Adsorbent Synthesis: Sample S
[0131] 3.0 ml aniline was added into 500 ml 2.0 M HCl solution
while stirring by a magnetic bar at room temperature on a hot
plate. 7.0 g of cyanamide (CM) was added into this aniline
solution. As an iron source, 10.0 g FeCl.sub.3 was added into the
(aniline+cyanamide) solution. After dissolving the FeCl.sub.3, 5.0
g of (NH.sub.4).sub.2S.sub.2O.sub.8 (ammonium persulfate, APS) as
oxidant was added into the solution to polymerize aniline. The
solution was stirred at room temperature for 4 hours to allow full
polymerization of aniline. 0.4 g of carbon (MWV 295-R-03) was
ultrasonically dispersed for 3 hr in 120 ml of (water (100
ml)+isopropanol alcohol (20 ml) solution in advance, and mixed with
the above dispersion containing cyanamide (CM) and polyaniline
(PANI). The temperature of the hot plate was increased up to
80.degree. C., and the solution was dried while stirring until it
became a tar-like state. The subsequent heat-treatment for the
obtained material was performed at 800.degree. C. in nitrogen
atmosphere for 30 minutes. The heat-treated powder was ground by a
mortar, and the obtained powder was subsequently acid-leached in
300 ml 0.5 M H.sub.2SO.sub.4 at 80.degree. C. for 8 hours, and
fully washed by ample of DI water. After drying at 90.degree. C. in
vacuum oven overnight, this dried powder was heat-treated again at
500.degree. C. in nitrogen atmosphere for 30 minutes to get the
final adsorbent.
(CM+PANI)-Based Adsorbent Synthesis: Sample U
[0132] To make 1 wt % Au deposition, 2.9 g of Sample T was
sonicated in 500 ml DI water for 1 hour, and separately 0.0586 g of
HAuCl.sub.4.3H.sub.2O was dissolved in 100 ml DI water. The carbon
dispersion and the HAuCl.sub.4.3H.sub.2O solutions were mixed
together and stirred for 15 hours. Then the mixture was filtered
using a 0.45 micrometer membrane filter and dried in a vacuum oven
at 90.degree. C. overnight.
Desulfurization Capacity Measurement of Adsorbents
[0133] The liquid fuel used for determining the sulfur removal
capacity of adsorbents was a simulated model feedstock targeting
typical compositions of liquid fuel products generated from
hydroprocessing process with sulfur concentration at about 100 ppm.
The composition of the simulated liquid fuel was:
TABLE-US-00001 Liquid fuel for sulfur capacity measurement
Composition Dibenzothiophene (DBT) 50 ppmwt S 4,6-dimethyl
dibenzothiophene (DMDBT) 50 ppmwt S Phenathrene 0.5 wt %
2-Metylnaphethalene 3.0 wt % Hexylbenzene 16.5 wt % Hexadecane
isomer mixture .sup.~80 wt %
[0134] Two methods were used for measuring desulfurization capacity
of adsorbents according to practical applications. The measurement
of the dynamic desulfurization capacity (C.sub.dyn.) or
breakthrough desulfurization capacity of adsorbents was conducted
in a plug-flow fixed bed reactor system. Adsorbent of about 1 gram
was pre-dried at 120.degree. C. overnight in a vacuum oven and then
loaded into a stainless-steel tubing reactor in a dry box under dry
N.sub.2 atmosphere environment. The adsorbent-loaded reactor was
then installed to a desulfurization capacity measurement system.
The adsorption bed was activated at 100.degree. C. for 4 hours
under hydrogen flow at a rate of 100 mL/min to remove any adsorbed
moisture. The simulated liquid fuel feed comprising 50 ppm wt of S
in DBT and 50 ppm wt of S in DMDBT was run through the adsorption
bed with a liquid delivery pump at room temperature at LHSV of 0.5
to 2.0 h.sup.-1. The effluent liquid product was collected
periodically for S analysis for DBT and DMDBT concentration. At the
beginning, S concentration in the effluent of the liquid product
was nearly undetectable. The S concentration in the effluent liquid
gradually increased with time on stream when adsorbent is gradually
saturated with DBT and DMDBT compounds. The desulfurization
capacity was calculated at DBT or DMDBT breakthrough concentration
of 10 ppmwt S in the effluent liquid product. The desulfurization
capacity was calculated based on the amount of DBT and DMDBT
removed from liquid fuel to the weight of adsorbent. In this
experiment, the dynamic desulfurization capacity for DBT
(C.sub.dyn.DBT) and DMDBT (C.sub.dyn.DMDBT) were calculated based
on their concentration of 10 ppm in the effluent liquid,
respectively, using the equation below.
C.sub.(dyn. DBT)=W.sub.feed*S.sub.DBT/W.sub.absorbent*100%
C.sub.(dyn. DMDBT)=W.sub.feed*S.sub.DMDBT/W.sub.absorbent*100%
[0135] In which [0136] W.sub.feed: weight of testing feed in
contact with the adsorbent, grams [0137] S.sub.DBT: 50 ppm S of DBT
in the testing feed minus S of DBT in effluent, grams (S
concentration is converted from ppm to grams) [0138] S.sub.DMDBT:
50 ppm S of DMDBT in the testing feed minus S of DMDBT in effluent,
grams (S concentration is converted from ppm to grams) [0139]
W.sub.absorbent: weight of adsorbent in the testing adsorber
bed
[0140] The measurement of equilibrium desulfurization capacity,
hereafter named the percentage of S removed (R.sub.equi.) was
conducted in a flask equipped with agitation. Adsorbent of about
0.1 gram pre-dried at 120.degree. C. overnight in a vacuum oven was
loaded to the flask in a dry box under dry N.sub.2 atmosphere
environment. About 10 mL of the simulated liquid fuel comprising 50
ppm DBT and 50 ppm DMDBT was added to the flask according to the
ratio of adsorbent to liquid fuel ratio of 1 to 100 by weight. The
mixture was agitated at room temperature for 16 hours. Then the
liquid fuel was taken from the mixture for DBT and DMDBT analysis.
The equilibrium desulfurization capacity for DBT (R.sub.equi.DBT)
and for DMDBT (R.sub.equi.DMDBT) is calculated based on the
percentage of DBT and DMDBT removed after in contact with the
adsorbents.
R ( equi DBT ) = 50 ppm S of DBT - ppm S of DBT 50 ppm S of DBT
.times. 100 % ##EQU00001## R ( equi DMDBT ) = 50 ppm of DMDBT - ppm
S of DMDBT 50 ppm S of DMDBT .times. 100 % ##EQU00001.2##
[0141] In which [0142] ppm S of DBT or DMDBT is S in liquid after
in contact with adsorbents
Regeneration of Adsorbents
[0143] The adsorbent after the dynamic desulfurization capacity
measurement was regenerated by toluene solvent with over 95%
desulfurization capacity restored. In one embodiment, when S
concentration in the effluent liquid reached 10 ppm of combined DBT
and DMDBT in a dynamic desulfurization capacity measurement, the
simulated liquid fuel feed was replaced by toluene solvent to
regenerate the adsorbent by running through toluene solvent to the
adsorbent reactor for 2 hours at LHSV of 5 h.sup.-1. The toluene
solvent pump was then stopped. Hydrogen gas of 100 mL/min was
flowed through the reactor to flush out any residue liquid and to
dry the adsorbent at room temperature. The adsorbent was then
further dried in-situ at 100.degree. C. for 4 hours under the
hydrogen flow and then cooled down to room temperature for dynamic
desulfurization capacity measurement for the regenerated adsorbent.
In one embodiment, over 95% desulfurization capacity was restored.
In one embodiment, the regeneration of adsorbent was repeated for
10 times and, each time, over 95% desulfurization capacity was
restored.
[0144] Samples A, B, C, E, F, and G were synthesized to study
impacts of synthetic conditions on the desulfurization capacity of
metal nanoparticle deposited nitrogen-doped carbon adsorbent (or
metal/carbon nanocomposites). It showed that desulfurization
capacity reflected by C.sub.dyn. and R.sub.equi. depended on the
chemicals used and the heat treatment temperature.
[0145] Samples D, H, I, J, and K were synthesised using aniline and
cyanamide as nitrogen precursors. For samples J and K, the first
and second heat treatment temperatures were lowered to 800 and
500.degree. C., respectively, in comparison with samples D, H and
I. Sample I used nitric acid for leaching instead of sulfuric
acid.
[0146] Samples M and N suggested that N insertion into activated
carbon frameworks can be also be achieved by NH.sub.3 treatment.
Sample M showed R.sub.equi comparable to sample D. This approach
can greatly reduce the cost of making adsorbents.
[0147] Sample P was synthesized without the use of activated carbon
as a support while keeping all other synthetic conditions the same
as sample J. Sample P showed excellent desulfurization activity
(C.sub.dyn. and R.sub.equi.). Importantly, sample P is more
selective toward the steric-hindered DMDBT over DBT.
[0148] Au metal of 1 wt % was deposited on sample J for making
sample L and on sample S for making sample U using HAuCl.sub.4 as
Au source. In the synthesis of sample L, a reducing agent, sodium
borohydride, was used to reduce the deposited Au nano particles.
For sample U, no reducing agent was used in the second metal
depositing process. Au-deposited sample L showed a comparable
desulfurization capacity to its precursor of sample J. Sample U
showed greatly increased desulfurization capacity over its
precursor of sample S. Interestingly, the sample U showed great
affinity to steric-hindered DMDBT. In the equilibrium
desulfurization study, sample U showed nearly 100% selectivity
toward DMDBT.
[0149] For the purposes of this specification and appended claims,
unless otherwise indicated, all numbers expressing quantities,
percentages or proportions, and other numerical values used in the
specification and claims, are to be understood as being modified in
all instances by the term "about." Accordingly, unless indicated to
the contrary, the numerical parameters set forth in the following
specification and attached claims are approximations that can vary
depending upon the desired properties sought to be obtained by the
present invention. Furthermore, all ranges disclosed herein are
inclusive of the endpoints and are independently combinable.
Whenever a numerical range with a lower limit and an upper limit
are disclosed, any number falling within the range is also
specifically disclosed. Unless otherwise specified, all percentages
are in weight percent.
[0150] It is noted that, as used in this specification and the
appended claims, the singular forms "a," "an," and "the," include
plural references unless expressly and unequivocally limited to one
referent. As used herein, the term "include" and its grammatical
variants are intended to be non-limiting, such that recitation of
items in a list is not to the exclusion of other like items that
can be substituted or added to the listed items.
[0151] Unless otherwise specified, the recitation of a genus of
elements, materials or other components, from which an individual
component or mixture of components can be selected, is intended to
include all possible sub-generic combinations of the listed
components and mixtures thereof.
[0152] The invention illustratively disclosed herein suitably may
be practiced in the absence of any element which is not
specifically disclosed herein.
[0153] This written description uses examples to disclose the
invention, including the best mode, and also to enable any person
skilled in the art to make and use the invention. The patentable
scope is defined by the claims, and can include other examples that
occur to those skilled in the art. Such other examples are intended
to be within the scope of the claims if they have structural
elements that do not differ from the literal language of the
claims, or if they include equivalent structural elements with
insubstantial differences from the literal languages of the claims.
All citations referred herein are expressly incorporated herein by
reference.
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