CA1137275A - Chalcogenides of groups viii and viib - Google Patents
Chalcogenides of groups viii and viibInfo
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- CA1137275A CA1137275A CA000302783A CA302783A CA1137275A CA 1137275 A CA1137275 A CA 1137275A CA 000302783 A CA000302783 A CA 000302783A CA 302783 A CA302783 A CA 302783A CA 1137275 A CA1137275 A CA 1137275A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
- B01J27/02—Sulfur, selenium or tellurium; Compounds thereof
- B01J27/04—Sulfides
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
- B01J27/02—Sulfur, selenium or tellurium; Compounds thereof
- B01J27/04—Sulfides
- B01J27/043—Sulfides with iron group metals or platinum group metals
- B01J27/045—Platinum group metals
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
- B01J27/02—Sulfur, selenium or tellurium; Compounds thereof
- B01J27/057—Selenium or tellurium; Compounds thereof
- B01J27/0573—Selenium; Compounds thereof
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
- B01J27/02—Sulfur, selenium or tellurium; Compounds thereof
- B01J27/057—Selenium or tellurium; Compounds thereof
- B01J27/0576—Tellurium; Compounds thereof
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B19/00—Selenium; Tellurium; Compounds thereof
- C01B19/007—Tellurides or selenides of metals
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G55/00—Compounds of ruthenium, rhodium, palladium, osmium, iridium, or platinum
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- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/02—Amorphous compounds
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- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/20—Two-dimensional structures
- C01P2002/22—Two-dimensional structures layered hydroxide-type, e.g. of the hydrotalcite-type
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- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/60—Compounds characterised by their crystallite size
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- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/70—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data
- C01P2002/72—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data by d-values or two theta-values, e.g. as X-ray diagram
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- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
- C01P2004/62—Submicrometer sized, i.e. from 0.1-1 micrometer
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
- C01P2004/64—Nanometer sized, i.e. from 1-100 nanometer
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/12—Surface area
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/80—Compositional purity
Abstract
ABSTRACT OF THE DISCLOSURE
Chalcogenides having a particle size of less than 0.1 micron and a crystallite size of about 50.ANG. x 100.ANG. or less of the formula MXy wherein M
is ruthenium, rhodium, iridium or osmium, X is a chalcogenide selected from the group consisting of sulfur, selenium, tellurium and mixtures thereof, and y is a number ranging from about 0.1 to about 3 or M is technetium, rhenium or man-ganese and y is about 1.5 to about 4.
Chalcogenides having a particle size of less than 0.1 micron and a crystallite size of about 50.ANG. x 100.ANG. or less of the formula MXy wherein M
is ruthenium, rhodium, iridium or osmium, X is a chalcogenide selected from the group consisting of sulfur, selenium, tellurium and mixtures thereof, and y is a number ranging from about 0.1 to about 3 or M is technetium, rhenium or man-ganese and y is about 1.5 to about 4.
Description
~13~?d75;
A method is disclosed for the preparation of chalco-genides o the formula MXy ~herein M is selected from the group consisting of ruthenium, osmium, rhodium, irldiumî preferably ruthenlum, rhodium and lridium, most preEerably ruthenium, X
is selected rom the group consisting of sulfur, selenium, tellurium and mixtures thereof, preferably sulfur and selenium, most preferably sulfur; and y is a number ranging from about 0.1 to about 3, preferably 0.1 to about 2.5, or M is manganese, rhenium or technetium, and y is about 1.5 to about 4, prefer-ably about 2, which method comprises preparing a neat or nonaqueous reactive solution ox slurry wherein is added (i) a ruthenium, osmium, rhodium, iridium, manganese, rhenium or technetium salt, the anion of the salt preferably being select- !
ed from the group consisting of halide (preferably chloride), acetate, carboxylate, nitrate and sulfate, and (ii) a source of sulfide, hydrosulfide (HS ), selenide, tellurlde ions, and mixtures thereof, preferably sulfur and selenium, most prefer-ably sulfur, said source being selected from the group consist~
ing o~ K2X, KHX, Li2X, NaHX`, NH4~X, (NH4)2X, Na2X, (RNH3)2X, liHX,(R,R~NH2)2X, (R,RIR'~NH)2X wherein R, R7 and Rl' are the same or different Cl-C20 alkyl, C6 C20 Y
Cl-C8 alkyl, C6-Cl~ aryl and X is a chalcogenide select-ed from sulfur, selenium, tellurium, and mixtures thereof, preferably sulfur and selenium, most preferably sulfur. The reaction may be run neat, ~hat is, in the absence of any added solvent. Alternatively, a nonaqueous solvent may be utilized, and, if used at all, is selected from the group consisting of ethers having 4-8 carbons, acetoni~rile, benzonitrile, pyridine, propionitrlle, N-methylformamide, dimethyl formamide (DMF), l,2-dimethoxyethane (DME1r propylene carbonate, ammonia, aromatics of 6-20 carbons, preerably C6-C12, molten sulfur, sulfur dioxide, diglyme, ethylacetate, esters of from C4 to C5, l., ~
~IL;372~5 sulfolane, dimethylsulfite, ~ributylphosphate, Cl-C30 amines, preferably Cl-C~0, C5-C12 alkanes, preferably C6-C8, anhydrous acids such a9 formic, and glacial acetic, alkyl halides of from 1 to 20 carbon atomq, aryl halides of from C6-C20 wherein the halide is selected from the group consisting of C1, Br and I and typical hydrocarbon feedstreams. Te~rahydrofuran (THF), ethylacetate, dimethyl~ormamide (DMF), chlorobenzene, chloro-form, pyridine, propylene carbonate and acetone may be used as solvents of choice.
The reaction proceeds spontaneously upon mixing at low temperatures, temperatures below ~00C, and at atmospheric pressure. The products may be isolated by filtration and wash-ing using excess solvent (when a solvent is used) or by pumping off the coproduced anion salt if it is volatile. Osmium disulfide produced by the above method possesses a layered structure having lattice parameters a - 3~52 and c = 6.15 and a surface area of about 50 m2/gm. The technetium dichalco-genide and rhenium dichalcogenide also possess a layered structure, The manganese dichalcogenide possesses a pyrite structure or an MnS structure depending on conditions of preparation~
Compounds of the formula MXy wherein M, X and y are as deflned above, prspared by the low temperature, non-aqueous precipitation technique herein disclosed are superior sulfur-tolerant catalysts in catalytlc processes, for example, hydrodesulfurization (HDS), hydrodenitrogenation (HDN), hydro-conversion, hydrogenation.
U.S. Patent 3,291,720 to Dobres et al describes a process for hydrorefining and hydrocracking hydrocarbons with a supported xhodium sulfide catalyst. The rhodium catalyst ls prepared by impregnating a base with a rhodium solution ..~
~3~Z7~
such as of rhodium chloride and thenconverting to the sulfide in situ by generating an H2S atmosphere.
~. M. Jaeger and J, H. deBoer Proc. Acad. Sci.
Amsterdam 23 95-lO~ (1920) disclose that at lower temperatures (i.e.~vo C) quadxivalent Ru salts and (NH4)2S give a greenish~
black preclpitate which i9 soluble in an excess of the pre-cipitating agent~ It should be noted that the method of preparation involved in the article appears to be an aqueous technique.
Lutz et al, Z. Natur~orsch, Teil B, 1971, 26 (11), 1096~7'describe the preparation of heavy metal sulfides by precipitation from organic solvents. In2S7, CoS, NiS, CuS, ZnS, CdS, HgS, PbS, Ag2S and a number of thiospinels were precipitated from solutions of the metal naphthenate in C6H6, THF, or naph~halene by H2S.
Numerous examples exist in the art of the use of metal sulfides as hydrodesulfurization catalysts. Vol-Epshtein et al, Soviet 323,431, describes the desulfurization ;~
of naphthalene and naphthalene containing fractions by hydro-gen~tion under a pressure of hydrogen at elevated temperature using a catalyst consisting of palladium sulfide on a carrier.
The catalyst preerably contains 0.3 to 5% Pd. The process is carried out at 230-320C.
Dovell in U.S. 3,538,161 describes the preparation of the selenides and tellurides of Ru, Rh, Pd, Os, Ir and Pt and their use as catalysts in a number of organic reduc-tions. The selenides were prepared by passing H2Se gas through a solution of RuC14 (for example) in 50 ml of concen-trated HCl diluted to 700 ml by H20. Precipitation of Ru2Se3 was complete inrv l.S hrs. In like manner were pre-pared the selenides o~ Rh, Pd, Os, Ir and Pt and the ~ellu-ride~ of Ru, Rh, Pd, Os and Pt. ~iphenyl disulfide was ~ 4 -- /' ~372~i converted to thiophenol by the action of Rh telluride. Thus, no C-C bonds are broken and the process has not resulted in hydrodesulfurization. Schwartz in U.S. 2,448,790 describes stable colloidal solutions of sulur and metal sulfides.
Colloldal solutions of As, Se, Mo, Sb, Sn, Ti, Pt and ~u sul-~ides may be formed, for example, by dissolving one part of powdered As in ~ive parts of 30~ NH4HS at room temperature.
To one part of the resulting sulfoarsenate, olle part NH4 reslnoleate and one part H2O are added. The mixture is decom-posed with formalin or phorone until all the NH3 is combined with the aldehyde or ketone.
The Group VIIb di- and poly-chalcogenides (MXy wherein M is manganese, rhenium and technetium, X is sulfur, selenium and tellurium and y is 2 or greater) have tradition-ally been prepared, when preparation was possible at all, by high temperature solid state techniques, or by aqueous prep-aration methods which result in compounds possessing a high degree of trapped water and hydrolysis products. The di-and poly-chalcogenides have attracted great interest because of their highly anisotropic pxoperties and intercala*ion properties. Intercalates made using various metal chalco-genides are useful as lubricants, battery cathodes and super-conductors. (SPe Gamble et al, U S. 3,766,064).
However, a major drawback in the use of chalcogenides is the difficulty encountered in their preparation.
ReS~ is normally prepared by the thexmal decom-position of Re2S7, see J. Less Common Metals 24, 73-81, 1971. Re2S7 is itself prepared by treating acid perrhenate solutions with gaseous H2S. The brown precipitate which results is washed and dried over P2O5 or silica gel. The product obtained contains excPss sulfur and water~ Re2S7 ~37Z75 is amorphous to X-ray, This material i9 thermally decomposed.
At 400-450 C the product is still rich in excess sulfur and has a composition of about ReS2 ,~. Crystalline layered ReS2 which is obtained only at temperatures over 1100C. is no longèr amorphous to X-ray, possessing well developed crystal-lite structures and large particle sizes. A similar situation prevails for TcS2.
The stoichlometric ruthenium, rhodium, irldium, osmium, rhenium and technetium chalcogenides, prepared by the nonaqueous precipitation technique of the instant process are finely divided small composite particles or completely non-crystalline. They possess crystallite sizes of about 50 A x 100 A or less, and particle sizes of 0.1 micron (1000 A) or less, preferably less than 0.05 micron (500 A), that is, particulate material which is amorphous to X-ray diffraction (see "X-ray Diffraction by Polycrystalline Materials", Ed.
Ho5~ Stokes, H~P~ Rooksby and A.J.C. Wilson, Chapter 17, A.R.
Stokes, pg. 409, 1955, Publ., J. Wright, London).
Figure I is an X-ray comparison of cryskalline tri-clinic ReS2 with paracrystalline ReS~. The sharp X-ray pattern is that of ReS2 prepared by prior art technique while the broad pattern ls that of ReS2 prepared by the nonaqueous precipitation technique described in the instant specification.
From the figure it can be seen that the two materials are dramatlcally di~ferent physically. In regions where the prior art compounds give a sharp pattern, the compound of the instant invention does not exhibit any variation in signal intensity at all.
Particles of 0.05 micron (500 ~) or less exhibit blurred X-ray patterns or no X-ray pattern at all (amorphous).
Crystallite sizes of 50A x lOOA are determined by use of a scanning electron microscope (SEM). Layered stoichiometric ~13'727~i rhenium dichalcogenide ancl technetium dichalcogenide obtained by prior art high temperature synthesis techniques produce X ray patterns and therefore cannot be finely divided or of small particle or cyrstallite size In addition Re sulfides prepared below 400C by aqueous methods are never stoichio-metric and are always of the type ReS2~x.
Finely-divlded, high-surface area, small particle (0.1 mlcron ~1000 ~ or less, preferably less than O.OS
mlcron) small crystaliite tabout 50 A x 100 A or less) pro-ducts are described The chalcogenide is selected from the group consisting of sulfur, selenium, tellurium and mixtures thereof, preferably sulfur and selenium, most preferably, sulfur. These chalcogenldes are prepared by the low-tempera-ture nonaqueous precipltatlon of said material from solutions comprislng mlxtures of the salts of the metals, typical anions of the salts being halide (preferably chloride), acetate, carboxylate, perfluorocaxboxylate, amines, acetylacetonate, hexafluoroacetonate, sulfate and nitrate, the carbonaceous moiety being a Cl to C8, preferably Cl to C3 hydrocarbon or ~0 fluoxocarbon, with solutions of or slurries of sources of sulfide, selenide, telluride lons and mixtures thereof. The products of the low-temperature nonaqueous precipitation technique are distinguished from materials prepared by high-temperature (greater than 400C.) methods of the prior art by exhibiting markedly different surface areas, particle sizes and crystallinity characteristics.
A method is described for the synthesis of chalco-genides of the metals specified above which comprises prepar-ing a nonaqueous reactive solution or slurry wherein is added (i) a metal salt, the salt anion being selected from the group consistlng of halide, acetate, carboxylate, perfluorocarboxy-late, acetylacetonate, hexafluoroacetylacetonate and (ii) a L3~275 1 source of sulfide, selenide, telluride ions and mixtures
A method is disclosed for the preparation of chalco-genides o the formula MXy ~herein M is selected from the group consisting of ruthenium, osmium, rhodium, irldiumî preferably ruthenlum, rhodium and lridium, most preEerably ruthenium, X
is selected rom the group consisting of sulfur, selenium, tellurium and mixtures thereof, preferably sulfur and selenium, most preferably sulfur; and y is a number ranging from about 0.1 to about 3, preferably 0.1 to about 2.5, or M is manganese, rhenium or technetium, and y is about 1.5 to about 4, prefer-ably about 2, which method comprises preparing a neat or nonaqueous reactive solution ox slurry wherein is added (i) a ruthenium, osmium, rhodium, iridium, manganese, rhenium or technetium salt, the anion of the salt preferably being select- !
ed from the group consisting of halide (preferably chloride), acetate, carboxylate, nitrate and sulfate, and (ii) a source of sulfide, hydrosulfide (HS ), selenide, tellurlde ions, and mixtures thereof, preferably sulfur and selenium, most prefer-ably sulfur, said source being selected from the group consist~
ing o~ K2X, KHX, Li2X, NaHX`, NH4~X, (NH4)2X, Na2X, (RNH3)2X, liHX,(R,R~NH2)2X, (R,RIR'~NH)2X wherein R, R7 and Rl' are the same or different Cl-C20 alkyl, C6 C20 Y
Cl-C8 alkyl, C6-Cl~ aryl and X is a chalcogenide select-ed from sulfur, selenium, tellurium, and mixtures thereof, preferably sulfur and selenium, most preferably sulfur. The reaction may be run neat, ~hat is, in the absence of any added solvent. Alternatively, a nonaqueous solvent may be utilized, and, if used at all, is selected from the group consisting of ethers having 4-8 carbons, acetoni~rile, benzonitrile, pyridine, propionitrlle, N-methylformamide, dimethyl formamide (DMF), l,2-dimethoxyethane (DME1r propylene carbonate, ammonia, aromatics of 6-20 carbons, preerably C6-C12, molten sulfur, sulfur dioxide, diglyme, ethylacetate, esters of from C4 to C5, l., ~
~IL;372~5 sulfolane, dimethylsulfite, ~ributylphosphate, Cl-C30 amines, preferably Cl-C~0, C5-C12 alkanes, preferably C6-C8, anhydrous acids such a9 formic, and glacial acetic, alkyl halides of from 1 to 20 carbon atomq, aryl halides of from C6-C20 wherein the halide is selected from the group consisting of C1, Br and I and typical hydrocarbon feedstreams. Te~rahydrofuran (THF), ethylacetate, dimethyl~ormamide (DMF), chlorobenzene, chloro-form, pyridine, propylene carbonate and acetone may be used as solvents of choice.
The reaction proceeds spontaneously upon mixing at low temperatures, temperatures below ~00C, and at atmospheric pressure. The products may be isolated by filtration and wash-ing using excess solvent (when a solvent is used) or by pumping off the coproduced anion salt if it is volatile. Osmium disulfide produced by the above method possesses a layered structure having lattice parameters a - 3~52 and c = 6.15 and a surface area of about 50 m2/gm. The technetium dichalco-genide and rhenium dichalcogenide also possess a layered structure, The manganese dichalcogenide possesses a pyrite structure or an MnS structure depending on conditions of preparation~
Compounds of the formula MXy wherein M, X and y are as deflned above, prspared by the low temperature, non-aqueous precipitation technique herein disclosed are superior sulfur-tolerant catalysts in catalytlc processes, for example, hydrodesulfurization (HDS), hydrodenitrogenation (HDN), hydro-conversion, hydrogenation.
U.S. Patent 3,291,720 to Dobres et al describes a process for hydrorefining and hydrocracking hydrocarbons with a supported xhodium sulfide catalyst. The rhodium catalyst ls prepared by impregnating a base with a rhodium solution ..~
~3~Z7~
such as of rhodium chloride and thenconverting to the sulfide in situ by generating an H2S atmosphere.
~. M. Jaeger and J, H. deBoer Proc. Acad. Sci.
Amsterdam 23 95-lO~ (1920) disclose that at lower temperatures (i.e.~vo C) quadxivalent Ru salts and (NH4)2S give a greenish~
black preclpitate which i9 soluble in an excess of the pre-cipitating agent~ It should be noted that the method of preparation involved in the article appears to be an aqueous technique.
Lutz et al, Z. Natur~orsch, Teil B, 1971, 26 (11), 1096~7'describe the preparation of heavy metal sulfides by precipitation from organic solvents. In2S7, CoS, NiS, CuS, ZnS, CdS, HgS, PbS, Ag2S and a number of thiospinels were precipitated from solutions of the metal naphthenate in C6H6, THF, or naph~halene by H2S.
Numerous examples exist in the art of the use of metal sulfides as hydrodesulfurization catalysts. Vol-Epshtein et al, Soviet 323,431, describes the desulfurization ;~
of naphthalene and naphthalene containing fractions by hydro-gen~tion under a pressure of hydrogen at elevated temperature using a catalyst consisting of palladium sulfide on a carrier.
The catalyst preerably contains 0.3 to 5% Pd. The process is carried out at 230-320C.
Dovell in U.S. 3,538,161 describes the preparation of the selenides and tellurides of Ru, Rh, Pd, Os, Ir and Pt and their use as catalysts in a number of organic reduc-tions. The selenides were prepared by passing H2Se gas through a solution of RuC14 (for example) in 50 ml of concen-trated HCl diluted to 700 ml by H20. Precipitation of Ru2Se3 was complete inrv l.S hrs. In like manner were pre-pared the selenides o~ Rh, Pd, Os, Ir and Pt and the ~ellu-ride~ of Ru, Rh, Pd, Os and Pt. ~iphenyl disulfide was ~ 4 -- /' ~372~i converted to thiophenol by the action of Rh telluride. Thus, no C-C bonds are broken and the process has not resulted in hydrodesulfurization. Schwartz in U.S. 2,448,790 describes stable colloidal solutions of sulur and metal sulfides.
Colloldal solutions of As, Se, Mo, Sb, Sn, Ti, Pt and ~u sul-~ides may be formed, for example, by dissolving one part of powdered As in ~ive parts of 30~ NH4HS at room temperature.
To one part of the resulting sulfoarsenate, olle part NH4 reslnoleate and one part H2O are added. The mixture is decom-posed with formalin or phorone until all the NH3 is combined with the aldehyde or ketone.
The Group VIIb di- and poly-chalcogenides (MXy wherein M is manganese, rhenium and technetium, X is sulfur, selenium and tellurium and y is 2 or greater) have tradition-ally been prepared, when preparation was possible at all, by high temperature solid state techniques, or by aqueous prep-aration methods which result in compounds possessing a high degree of trapped water and hydrolysis products. The di-and poly-chalcogenides have attracted great interest because of their highly anisotropic pxoperties and intercala*ion properties. Intercalates made using various metal chalco-genides are useful as lubricants, battery cathodes and super-conductors. (SPe Gamble et al, U S. 3,766,064).
However, a major drawback in the use of chalcogenides is the difficulty encountered in their preparation.
ReS~ is normally prepared by the thexmal decom-position of Re2S7, see J. Less Common Metals 24, 73-81, 1971. Re2S7 is itself prepared by treating acid perrhenate solutions with gaseous H2S. The brown precipitate which results is washed and dried over P2O5 or silica gel. The product obtained contains excPss sulfur and water~ Re2S7 ~37Z75 is amorphous to X-ray, This material i9 thermally decomposed.
At 400-450 C the product is still rich in excess sulfur and has a composition of about ReS2 ,~. Crystalline layered ReS2 which is obtained only at temperatures over 1100C. is no longèr amorphous to X-ray, possessing well developed crystal-lite structures and large particle sizes. A similar situation prevails for TcS2.
The stoichlometric ruthenium, rhodium, irldium, osmium, rhenium and technetium chalcogenides, prepared by the nonaqueous precipitation technique of the instant process are finely divided small composite particles or completely non-crystalline. They possess crystallite sizes of about 50 A x 100 A or less, and particle sizes of 0.1 micron (1000 A) or less, preferably less than 0.05 micron (500 A), that is, particulate material which is amorphous to X-ray diffraction (see "X-ray Diffraction by Polycrystalline Materials", Ed.
Ho5~ Stokes, H~P~ Rooksby and A.J.C. Wilson, Chapter 17, A.R.
Stokes, pg. 409, 1955, Publ., J. Wright, London).
Figure I is an X-ray comparison of cryskalline tri-clinic ReS2 with paracrystalline ReS~. The sharp X-ray pattern is that of ReS2 prepared by prior art technique while the broad pattern ls that of ReS2 prepared by the nonaqueous precipitation technique described in the instant specification.
From the figure it can be seen that the two materials are dramatlcally di~ferent physically. In regions where the prior art compounds give a sharp pattern, the compound of the instant invention does not exhibit any variation in signal intensity at all.
Particles of 0.05 micron (500 ~) or less exhibit blurred X-ray patterns or no X-ray pattern at all (amorphous).
Crystallite sizes of 50A x lOOA are determined by use of a scanning electron microscope (SEM). Layered stoichiometric ~13'727~i rhenium dichalcogenide ancl technetium dichalcogenide obtained by prior art high temperature synthesis techniques produce X ray patterns and therefore cannot be finely divided or of small particle or cyrstallite size In addition Re sulfides prepared below 400C by aqueous methods are never stoichio-metric and are always of the type ReS2~x.
Finely-divlded, high-surface area, small particle (0.1 mlcron ~1000 ~ or less, preferably less than O.OS
mlcron) small crystaliite tabout 50 A x 100 A or less) pro-ducts are described The chalcogenide is selected from the group consisting of sulfur, selenium, tellurium and mixtures thereof, preferably sulfur and selenium, most preferably, sulfur. These chalcogenldes are prepared by the low-tempera-ture nonaqueous precipltatlon of said material from solutions comprislng mlxtures of the salts of the metals, typical anions of the salts being halide (preferably chloride), acetate, carboxylate, perfluorocaxboxylate, amines, acetylacetonate, hexafluoroacetonate, sulfate and nitrate, the carbonaceous moiety being a Cl to C8, preferably Cl to C3 hydrocarbon or ~0 fluoxocarbon, with solutions of or slurries of sources of sulfide, selenide, telluride lons and mixtures thereof. The products of the low-temperature nonaqueous precipitation technique are distinguished from materials prepared by high-temperature (greater than 400C.) methods of the prior art by exhibiting markedly different surface areas, particle sizes and crystallinity characteristics.
A method is described for the synthesis of chalco-genides of the metals specified above which comprises prepar-ing a nonaqueous reactive solution or slurry wherein is added (i) a metal salt, the salt anion being selected from the group consistlng of halide, acetate, carboxylate, perfluorocarboxy-late, acetylacetonate, hexafluoroacetylacetonate and (ii) a L3~275 1 source of sulfide, selenide, telluride ions and mixtures
2 thereof, preferably sul~ide and selenide, mos~ preferably sul-
3 fide, said sources conveniently being Li2X, hydrosulide salts
4 [i.e., N~X, ~1411~], (~14)2~, Na2X, 1~2X, (RN~13)2X- (R,i' N~2)2 (R,R',R" NH)2X ~herein ~, R', R" are the same or different 6 and are selec~ed from the group consisting o Cl-C20 ~lkyl, 7 prefexably Cl to Cg, or C6-C20 aryl, preerably C6 to Cl2, 8 and X is the chalcogenide selected rom the group con~isting 9 of sulfur, selenlum, teIlurium and mixtures thereo~, prefer-ably sulfur and selenium, most preferably sulfur and a non-11 aqueous solvent selected from the group consisting o ethers 12 o~ from C4 to C~J acetonitrile, benæonitrile, dimethylform-13 amide (DMF), propylene carbonate, aromatics of C6 C20 carbons, 14 pre~erably C6 to C12, ammonia, molten sul~ur, diglyme, sulfur lS dioxide, ethylaceta~e, esters o from C4 to Cg, sulfolane, 16 tributylphosphate, anhydrous acids, such as ~ormic acid, gla 17 cial acetic acid, alkylhalides of from Cl ~ ~20. prefera~ly 18 Cl to Cs~ and arylhalides of from C6 to C~o, preferably C6 ~
19 Clo, pyridine, propioni~rile, N-methylformamide, dimethyl-suli~e, Cl-C30 amines, preerably Cl to C20, Cs - C12 alkanes, 21 pre~erably Cs to Cg. The solven~s o~ choice are te~rahydro~
22 furan (THF~ dimethyl~ormamide (DMF) 3 chl~robenzene, chloro-.
23 form, pyridine, e~hyl ace~ate and acetone. Alternatively, 24 the reaction may be run nea~J that is, in ~he absence of any solvent. The products may be isolated by filterlng, washing 26 with e~cess solven~ or.by pumping of~ the anion salts i~ they 27 are volatile. In si~uations wherein the sulfide, selenide 28 and/or ~ellur.de ion sources are already solutions, no addi-2~ tional solven~ is needed during the course of the reaction ~ although a volume of nonaque~us solvPnt (i.e. one which does 31 not offer or accept protons, i.e. aprotic as opposed to protic 32 may be added so as to facilitate product isola~lon. When ,, . , . . , ~ . . . , , . . ~ .
~3~7~;
_ deslred, the material so obtalned ~ - 8a -,~ , ~L3~7~i can be pretreated for use as a catalyst, for example~ in an H2S~H2 atmosphere for ~everal hours, temperature of pretreat-ment being 300-600C, pre~erably 350-500C, the H2S~H2 atmos-phere being 1~ H2S to 100% H2S, the balance being H2, prefer~
ably 3~ to 20% lI2S, the balance being H2. Alternatively, the material can be pretreated in situ in the catalytic reactor, the sulfur-containing hydrocarbon feed stream alone being sufficient to e~fect the desired change. Typically, the cata-lytic processes will be run at temperatures ranging from ambient to 500C, preferably 100~450C, most preferably 200 400 C, at pressures o~ from 1 atm-5000 psig of H2, preferably 100 - 2000 p9ig o H2 and at space velocities o from 0.1 - 10 V/V/hr., preferably .1-5 V/V/hr. When the compound is to be used as a catalyst, it may be prepared ln the catalytic reac-tion vessel by introducing the appropriate starting materials (from those recited above) into the vessel, using the hydro-carbon feed stream to be catalytically treated as ~he non-aqueous solvent.
When one uses a Group VIII chalcogenide of the type descrlbed above in the supported state, the metal chalcogenide will be present at from 0.01 to 30 wt. % metal based on total catalyst, preferably 0.1 to lQ wt. ~ metal based on total catalyst.
Typically, a metal salt such as ReCl~ or RUC14 i5 reacted with a solution of, or a slurry of a convenient sul-fide, selenide or telluride lon source such as Li2S, Na2S, K2S, hydrosulfide salt (i.e. NH4H5, NaHS), (NH4j2S, (RNH3)~S, (~,R'NH2)2S, (R,R~RIlNH)2S, wherein R, R7 and R'l are the same or different Cl_C20 alkyl or C6-C20 aryl~ preerably Cl to C8 alkyl or C6-C12 aryl, Li2Se, Li2Te, (NH4)2Se, in a non-aqueous solvent such as THF, other organoethers, acetonitrile propylene carbonate, DMF, molten sulfur, etc. The reaction _ 9 ~
which occurs may be represented by the following equation (when M is a ~4 metal ion):
nonaqueous MZ4 ~ 2 A2X ~ MX2~ ~ 4 ~z solvent or neat where M - a Group VIII or VIIb metal, A = alkali metal ~ NH4 ~ R, R' R~' NH ~, R, R NH2 ~ or other cation as defined above, Z - convenient anion such as Cl ~, Br ~ I ~
acetate Q carboxylate ~ nitrate ~, sulfate ~ etc. as recited above, X = sulfur, selenium or tellurium.
Any convenient souroe of M ~ M ~ , preferably M ~ 3 and M ~ 4 can be used. Complexes ~ormed in solution which can be isolated as solids may be used as M ~ sources.
The reaction is normally but not necessarily, con-ductPd in the absence of an excess of sulfide, selenide or telluride, although other starting materials may be present in excess~ Since particle size depends on the rate of mixing of reagents, the reaction may be allowed to proceed instantly, upon total admixtuxe o~ one reagent to the reaction solution yielding fine products or, upon the measured addition of small increments of one reagent to the reaction solution, the reaction not achieving totality for several daysO
The temperature of the reaction may range from -78C
to 400C, e.g., 0 to 400C., preferably ambient (25C) to 300 C. It should be noted that any convenient temperatures below 400C. may be used, the only requirement being that the low temperature chosen be above the freezing point of the non-aqeuous solutlon used or slurry f~rmed. These temperatures are markedly lower than those needed when prepariny dichalco-genides via solld state or gas phase methods wherein reaction temperatures up to and exceeding 1000C are commonplace.
-, -- 10 --1~3~7~
The products obtalned from the low temperature nonaqueous precipltation technique are di- and polychalco-genides, particularly dichalcogenldes and more particularly disulfides, and have unlque properties. The products may be stolchiometric~ The partlcle size and cr~stallinity of these materials can be greatl~ varied by practiclng the preparative methods of the instant lnvention. Surface areas can be ralsed tothe point where the dichalcogenide will remain suspended in solutlon and homogeneous dispersions created~ This effect can be increased by using more polar nonaqueous solvents such as DMF or basic solvents 5uch as pyrldine or propylene carbonate whlch have a natural tendency to attach to the sùlfur layers and cause dlspersions. These same solvents are those which tend to intercalate in crystalllne transition metal dichalcogenides. Such dispersions can be gelled by proper variation o~ conditions or adsorbed on basic substrates such as CaO.
The above-mentioned preparation allows one to choose between a wide range of partlcle size, crystalllnity and 3urface area compounds. Sollds may be prepared which have the ~ollowing properties:
A. Hlgh-sur~ace area, small-particle size and ; amorphous structure. Such characteristics are achieved by use of a solvent which may have the ability to form inter-calation complexes with the chalcogenide. Alternatively, chalcogenides formed neat or in the absence of an interca-lation solvent may be treated with an intercalate to achieve the same result. Such intercalates may be a strong Lewis base such as pyridine, ammonia, Cl - C20 amines, aldehydes, ketones, amides, heterocycllc bases, anilines and ethers The intercalated chalcogenide i5 then subjected to heat treating at between 75-200C with pumping under vacuum when ~37~7~
necessary to drive off the lntercalating solvent leaving a high-surface area, small~particle size amorphous chalco-genide. Example: ReS2 or RuS2 prepared from ethylacetate and treated at 400C in H2~ gave a poorly defined X-ray pattern which lndicates a crystallite size of at least le~s than 0.1 micron and a Brunauer, Emmett and Teller (BET) surface area of 50 m /gm. Treatment temperatures less than 400C yield hlgh-surface areas or completely amorphous solids,.
B. Low surface area, small particle size and amorphous solids. Example. The same ReS2 or RuS2 as men-tioned ln tA) if not heat treated gave an amorphous X-ray pattern and a BET surface area of 10 m /gmO
C. Homogeneous disper~ions: conditions can be arranged a~ above so that all or part of the chalcogenides remain in suspension as a homogeneous dispersion in solution.
Appropriate solvents which are used for the generation of dispersions include propylene carbonate, dimethylformamide (D~ pyridine, acetonitrile, benzonitrlle, propionitrile, l,2 di-methoxyethane, dlgylme and N-methylformamide. Such materials can be removed ~rom solution by the addition of a basic solid such as MgO. For example, ReS2 or RuS2 prepared in propylene carbonate will result in a black opaque disper-sion. The ReS2 or RuS2 may be adsorbed by shaking the dis-persion with MgO which results in a dark gray material when dried. Correspondingly, the original solution is clear after such treatment with the excess MgO.
D. High-surface area composite - Group VIII or VIIb dichalcogenide~metal oxlde ~olids. Composite material may be prepared with the chalcogenide being adsorbed on a metal oxide due to the Lewls acid nature of the chalcogenide.
Exc~mple: ReS2 or RuS2~MgO material described in (C~ above.
The metal oxides which may be used in this embodiment are any metal oxide9 which exhibit Lewis acidity, for example, MgO, CaO, ~12O3, the oxides of Groups IV, V and VI of the Periodic Table of the Elements, preferably TiO2, ZrO2; alternatively, acti~iated carbon ox charcoal may be used.
E. Gels and Glasses - Gels containing the Group VIII ox VIIb dichalcogenides may be produced by preparation in certain amines, such as ~rihexylamine, or by carefully removing solvent from ethylacetate solutions of ReC15 or RuC14~2Li2S. The gels produced yield glasses when the sol-vents are removed.
All of the preparative work described below was carried out either in a dry box or under a blanket o~ nitro-gen, Both the starting metal ~4 and ~5 compounds and the sul~ides and selenides thus produced are sensitive to moisture and oxygen, especially in ~inely powdered form as results from the heterogeneous precipitation methods described. All solvents were dried by standard techniques prior to use and anhydrous reagents were always employed.
Chalcogenides 1. Ruthenium RuS2 was generally prepared from the tetrachloride but preparation from the trichlorida is also possible~ There were significant differences in the activity and selectivity between the two preparations:
RuC14 ~ 2 Li2S ~ RUS2 ~ 4 LiCl 7.40 gm of RuC14 (30.47 mm) was dissolved in 100 ml of ethyl acetate and 2.80 gm Li2S (60.94 mm) was added in the dry state. Thls was stirred for 4 hours and filtered, yielding a black powder which was still wet with ethylacetate. The filtrate was partially green indicatiny suspended particles ~ 13 -~L~372~5 of RuS2. The sample was then heat treated in pure H2S at400 C for 1.5 hours, cooled to room temperature, washed with 12~ acetic acid, ~.tltered and heated again in pure H2S for 1.5 hours~ This treatment yielded a black powder wetghing 6~683 gms ~theoretical yleld of RuS2 = 5.11 gms) which showed only RuS2 in the X-ray pattern. Chemical analysis showed 3.89 moles of sulfur ~or each ruthenium atom with less than ~%
chlorine. Infrared analysis also indicated the presence of an extra phase. This extra phase appears to be atomic sulfur caused by the catalytic decomposition of H2S = H2 ~ 5 This was further confirmed by treatment of the RuS2 as produced above with mixtures of H2/H2S providing lower partial pressures of sulfur. For example, RuS2 after being run in the flow reactor for more than 1000 hours showed only RuS2 in the X ray pattern and gave the following chemical analysis:
Theoretical 7be~etiral xuS~ Measured 1- ?5 o. 25 Ru61.2 % 62.4 % 63.1 %
S 38.8 ~ 34.6 % 35.0 %
C 0.0 % 2.1 ~ 1 9 %
~ O
Total100.0 % 99~1 ~ 100.0 %
All results indicate that RuS2 itself has a range of possible non-stoichiometry and the above example corresponds to the formula RuSl 75. It may be noted that if one su~st~tutes the carbon found in the analysis ~or the missing sulfur, this give~ a compound of formula RuS1 75Co 25. This suggests that the carbon is replacing the sul~ur on the surface of the catalytically active particles, The infrared spectrum of RuS2 which has been treated to remove excess sulfur is very similar to that of FeS~. These compounds freshly prepared had BErr surface areas ln the neighborhood of 70 m /gm.
'~;, 3L~ 3~727~i 2RuCl3 ~ 3Li2S et1lyl acet ~ Ru2S3 ~ 61,iCl ~u2S3 -~ H2S 400 C~ 2RuS2 ~ H2 The preparation erom the trichloride is exactly analogous to the above preparation from the tetrachlorlde yielding RuS2.
The catalytic activity i5 slightly different for the two preparations. This is undoubtedly due to a difference in the physical state o~ the RuS2.
2 osmium OsS2 was prepared from the tetrachloride:
OsCl4 ~ 2Li2S--~OsS2 -~ 4LiCl 4 grams of OsCl4 was added to lO0 ml of ethyl acetate yield-ing a greenish solution. l.12 gm of Li2S was added as the solid and the solution turned black with stirring. The solution was filtered and a black powder was obtained which was treated at 400C in a stream o H2/l5% H2S for 2 hours.
The solid was then washed with 12~ acetic acid and treated again for 2 hours at 400C in H2/l5~ H2S. The resulting black powder weighed 2.80 gms (theoretical = 3.10 gms) with a BET surface area of 20 m2/gm. X-ray analysis as discussed below indicated that the OsS2 was a previously unknown layered compound which could be converted to the known pyrite type by heatlng in vacuum at 600C. The osmium sulfide prepared by this method was con~erted to Os metal under reactor conditions. However, the chemical analysis indicated that the stoichlometry was OsS. In H~/l5~ H2S the OsS2 had been partially converted to the metal after several hours.
3. Iridium __ IrS2 was prepared from the tetrachloride:
IrCl4 ~ 2Li2S --~t IrS2 ~ 4I,lCl 2.00 gms of IrCl~ was dissolved in 175 ml of ethyl acetate.
~ . I .
~37~
The solution became dark brown. To this 0.55 gms of Li2S
was added neat with the color changing from a dark brown to golden. After stirring ~or 3.5 hours a golden powder was recovered, 1.8 gms of the product wa~ heat treated in 15~
H2S/N2 ~or 2 hour9, washed in 12% acetic acld then reheated in 15~ H2S/N2 ~or 2 hours yielding a black powder with a BET
surface area o 60 M2/gm, The acetic acid wash caused bubbling and fizzing whlch indicates lncomplete reaction of Li2S. As in the case of RuS2 prepared in H2S the product contained excess sulfur. X~ray powder diffraction yielded a very diffuse pattern probably of pyrite type IrS3. However, this compound reverted in the reactor to Ir metal ~ S .
4. Rhodium Rh2S3 was prepared in the same manner as in the previous examples from the trichloride: -2RhC13 + 3Li2S -,~Rh2S3 ~ 6LiCl X-ray analysis before and a~ter reaction indicated the pre sence o~ Rh2S3 which had a BET sur~ace area of 15 M2/gm.
19 Clo, pyridine, propioni~rile, N-methylformamide, dimethyl-suli~e, Cl-C30 amines, preerably Cl to C20, Cs - C12 alkanes, 21 pre~erably Cs to Cg. The solven~s o~ choice are te~rahydro~
22 furan (THF~ dimethyl~ormamide (DMF) 3 chl~robenzene, chloro-.
23 form, pyridine, e~hyl ace~ate and acetone. Alternatively, 24 the reaction may be run nea~J that is, in ~he absence of any solvent. The products may be isolated by filterlng, washing 26 with e~cess solven~ or.by pumping of~ the anion salts i~ they 27 are volatile. In si~uations wherein the sulfide, selenide 28 and/or ~ellur.de ion sources are already solutions, no addi-2~ tional solven~ is needed during the course of the reaction ~ although a volume of nonaque~us solvPnt (i.e. one which does 31 not offer or accept protons, i.e. aprotic as opposed to protic 32 may be added so as to facilitate product isola~lon. When ,, . , . . , ~ . . . , , . . ~ .
~3~7~;
_ deslred, the material so obtalned ~ - 8a -,~ , ~L3~7~i can be pretreated for use as a catalyst, for example~ in an H2S~H2 atmosphere for ~everal hours, temperature of pretreat-ment being 300-600C, pre~erably 350-500C, the H2S~H2 atmos-phere being 1~ H2S to 100% H2S, the balance being H2, prefer~
ably 3~ to 20% lI2S, the balance being H2. Alternatively, the material can be pretreated in situ in the catalytic reactor, the sulfur-containing hydrocarbon feed stream alone being sufficient to e~fect the desired change. Typically, the cata-lytic processes will be run at temperatures ranging from ambient to 500C, preferably 100~450C, most preferably 200 400 C, at pressures o~ from 1 atm-5000 psig of H2, preferably 100 - 2000 p9ig o H2 and at space velocities o from 0.1 - 10 V/V/hr., preferably .1-5 V/V/hr. When the compound is to be used as a catalyst, it may be prepared ln the catalytic reac-tion vessel by introducing the appropriate starting materials (from those recited above) into the vessel, using the hydro-carbon feed stream to be catalytically treated as ~he non-aqueous solvent.
When one uses a Group VIII chalcogenide of the type descrlbed above in the supported state, the metal chalcogenide will be present at from 0.01 to 30 wt. % metal based on total catalyst, preferably 0.1 to lQ wt. ~ metal based on total catalyst.
Typically, a metal salt such as ReCl~ or RUC14 i5 reacted with a solution of, or a slurry of a convenient sul-fide, selenide or telluride lon source such as Li2S, Na2S, K2S, hydrosulfide salt (i.e. NH4H5, NaHS), (NH4j2S, (RNH3)~S, (~,R'NH2)2S, (R,R~RIlNH)2S, wherein R, R7 and R'l are the same or different Cl_C20 alkyl or C6-C20 aryl~ preerably Cl to C8 alkyl or C6-C12 aryl, Li2Se, Li2Te, (NH4)2Se, in a non-aqueous solvent such as THF, other organoethers, acetonitrile propylene carbonate, DMF, molten sulfur, etc. The reaction _ 9 ~
which occurs may be represented by the following equation (when M is a ~4 metal ion):
nonaqueous MZ4 ~ 2 A2X ~ MX2~ ~ 4 ~z solvent or neat where M - a Group VIII or VIIb metal, A = alkali metal ~ NH4 ~ R, R' R~' NH ~, R, R NH2 ~ or other cation as defined above, Z - convenient anion such as Cl ~, Br ~ I ~
acetate Q carboxylate ~ nitrate ~, sulfate ~ etc. as recited above, X = sulfur, selenium or tellurium.
Any convenient souroe of M ~ M ~ , preferably M ~ 3 and M ~ 4 can be used. Complexes ~ormed in solution which can be isolated as solids may be used as M ~ sources.
The reaction is normally but not necessarily, con-ductPd in the absence of an excess of sulfide, selenide or telluride, although other starting materials may be present in excess~ Since particle size depends on the rate of mixing of reagents, the reaction may be allowed to proceed instantly, upon total admixtuxe o~ one reagent to the reaction solution yielding fine products or, upon the measured addition of small increments of one reagent to the reaction solution, the reaction not achieving totality for several daysO
The temperature of the reaction may range from -78C
to 400C, e.g., 0 to 400C., preferably ambient (25C) to 300 C. It should be noted that any convenient temperatures below 400C. may be used, the only requirement being that the low temperature chosen be above the freezing point of the non-aqeuous solutlon used or slurry f~rmed. These temperatures are markedly lower than those needed when prepariny dichalco-genides via solld state or gas phase methods wherein reaction temperatures up to and exceeding 1000C are commonplace.
-, -- 10 --1~3~7~
The products obtalned from the low temperature nonaqueous precipltation technique are di- and polychalco-genides, particularly dichalcogenldes and more particularly disulfides, and have unlque properties. The products may be stolchiometric~ The partlcle size and cr~stallinity of these materials can be greatl~ varied by practiclng the preparative methods of the instant lnvention. Surface areas can be ralsed tothe point where the dichalcogenide will remain suspended in solutlon and homogeneous dispersions created~ This effect can be increased by using more polar nonaqueous solvents such as DMF or basic solvents 5uch as pyrldine or propylene carbonate whlch have a natural tendency to attach to the sùlfur layers and cause dlspersions. These same solvents are those which tend to intercalate in crystalllne transition metal dichalcogenides. Such dispersions can be gelled by proper variation o~ conditions or adsorbed on basic substrates such as CaO.
The above-mentioned preparation allows one to choose between a wide range of partlcle size, crystalllnity and 3urface area compounds. Sollds may be prepared which have the ~ollowing properties:
A. Hlgh-sur~ace area, small-particle size and ; amorphous structure. Such characteristics are achieved by use of a solvent which may have the ability to form inter-calation complexes with the chalcogenide. Alternatively, chalcogenides formed neat or in the absence of an interca-lation solvent may be treated with an intercalate to achieve the same result. Such intercalates may be a strong Lewis base such as pyridine, ammonia, Cl - C20 amines, aldehydes, ketones, amides, heterocycllc bases, anilines and ethers The intercalated chalcogenide i5 then subjected to heat treating at between 75-200C with pumping under vacuum when ~37~7~
necessary to drive off the lntercalating solvent leaving a high-surface area, small~particle size amorphous chalco-genide. Example: ReS2 or RuS2 prepared from ethylacetate and treated at 400C in H2~ gave a poorly defined X-ray pattern which lndicates a crystallite size of at least le~s than 0.1 micron and a Brunauer, Emmett and Teller (BET) surface area of 50 m /gm. Treatment temperatures less than 400C yield hlgh-surface areas or completely amorphous solids,.
B. Low surface area, small particle size and amorphous solids. Example. The same ReS2 or RuS2 as men-tioned ln tA) if not heat treated gave an amorphous X-ray pattern and a BET surface area of 10 m /gmO
C. Homogeneous disper~ions: conditions can be arranged a~ above so that all or part of the chalcogenides remain in suspension as a homogeneous dispersion in solution.
Appropriate solvents which are used for the generation of dispersions include propylene carbonate, dimethylformamide (D~ pyridine, acetonitrile, benzonitrlle, propionitrile, l,2 di-methoxyethane, dlgylme and N-methylformamide. Such materials can be removed ~rom solution by the addition of a basic solid such as MgO. For example, ReS2 or RuS2 prepared in propylene carbonate will result in a black opaque disper-sion. The ReS2 or RuS2 may be adsorbed by shaking the dis-persion with MgO which results in a dark gray material when dried. Correspondingly, the original solution is clear after such treatment with the excess MgO.
D. High-surface area composite - Group VIII or VIIb dichalcogenide~metal oxlde ~olids. Composite material may be prepared with the chalcogenide being adsorbed on a metal oxide due to the Lewls acid nature of the chalcogenide.
Exc~mple: ReS2 or RuS2~MgO material described in (C~ above.
The metal oxides which may be used in this embodiment are any metal oxide9 which exhibit Lewis acidity, for example, MgO, CaO, ~12O3, the oxides of Groups IV, V and VI of the Periodic Table of the Elements, preferably TiO2, ZrO2; alternatively, acti~iated carbon ox charcoal may be used.
E. Gels and Glasses - Gels containing the Group VIII ox VIIb dichalcogenides may be produced by preparation in certain amines, such as ~rihexylamine, or by carefully removing solvent from ethylacetate solutions of ReC15 or RuC14~2Li2S. The gels produced yield glasses when the sol-vents are removed.
All of the preparative work described below was carried out either in a dry box or under a blanket o~ nitro-gen, Both the starting metal ~4 and ~5 compounds and the sul~ides and selenides thus produced are sensitive to moisture and oxygen, especially in ~inely powdered form as results from the heterogeneous precipitation methods described. All solvents were dried by standard techniques prior to use and anhydrous reagents were always employed.
Chalcogenides 1. Ruthenium RuS2 was generally prepared from the tetrachloride but preparation from the trichlorida is also possible~ There were significant differences in the activity and selectivity between the two preparations:
RuC14 ~ 2 Li2S ~ RUS2 ~ 4 LiCl 7.40 gm of RuC14 (30.47 mm) was dissolved in 100 ml of ethyl acetate and 2.80 gm Li2S (60.94 mm) was added in the dry state. Thls was stirred for 4 hours and filtered, yielding a black powder which was still wet with ethylacetate. The filtrate was partially green indicatiny suspended particles ~ 13 -~L~372~5 of RuS2. The sample was then heat treated in pure H2S at400 C for 1.5 hours, cooled to room temperature, washed with 12~ acetic acid, ~.tltered and heated again in pure H2S for 1.5 hours~ This treatment yielded a black powder wetghing 6~683 gms ~theoretical yleld of RuS2 = 5.11 gms) which showed only RuS2 in the X-ray pattern. Chemical analysis showed 3.89 moles of sulfur ~or each ruthenium atom with less than ~%
chlorine. Infrared analysis also indicated the presence of an extra phase. This extra phase appears to be atomic sulfur caused by the catalytic decomposition of H2S = H2 ~ 5 This was further confirmed by treatment of the RuS2 as produced above with mixtures of H2/H2S providing lower partial pressures of sulfur. For example, RuS2 after being run in the flow reactor for more than 1000 hours showed only RuS2 in the X ray pattern and gave the following chemical analysis:
Theoretical 7be~etiral xuS~ Measured 1- ?5 o. 25 Ru61.2 % 62.4 % 63.1 %
S 38.8 ~ 34.6 % 35.0 %
C 0.0 % 2.1 ~ 1 9 %
~ O
Total100.0 % 99~1 ~ 100.0 %
All results indicate that RuS2 itself has a range of possible non-stoichiometry and the above example corresponds to the formula RuSl 75. It may be noted that if one su~st~tutes the carbon found in the analysis ~or the missing sulfur, this give~ a compound of formula RuS1 75Co 25. This suggests that the carbon is replacing the sul~ur on the surface of the catalytically active particles, The infrared spectrum of RuS2 which has been treated to remove excess sulfur is very similar to that of FeS~. These compounds freshly prepared had BErr surface areas ln the neighborhood of 70 m /gm.
'~;, 3L~ 3~727~i 2RuCl3 ~ 3Li2S et1lyl acet ~ Ru2S3 ~ 61,iCl ~u2S3 -~ H2S 400 C~ 2RuS2 ~ H2 The preparation erom the trichloride is exactly analogous to the above preparation from the tetrachlorlde yielding RuS2.
The catalytic activity i5 slightly different for the two preparations. This is undoubtedly due to a difference in the physical state o~ the RuS2.
2 osmium OsS2 was prepared from the tetrachloride:
OsCl4 ~ 2Li2S--~OsS2 -~ 4LiCl 4 grams of OsCl4 was added to lO0 ml of ethyl acetate yield-ing a greenish solution. l.12 gm of Li2S was added as the solid and the solution turned black with stirring. The solution was filtered and a black powder was obtained which was treated at 400C in a stream o H2/l5% H2S for 2 hours.
The solid was then washed with 12~ acetic acid and treated again for 2 hours at 400C in H2/l5~ H2S. The resulting black powder weighed 2.80 gms (theoretical = 3.10 gms) with a BET surface area of 20 m2/gm. X-ray analysis as discussed below indicated that the OsS2 was a previously unknown layered compound which could be converted to the known pyrite type by heatlng in vacuum at 600C. The osmium sulfide prepared by this method was con~erted to Os metal under reactor conditions. However, the chemical analysis indicated that the stoichlometry was OsS. In H~/l5~ H2S the OsS2 had been partially converted to the metal after several hours.
3. Iridium __ IrS2 was prepared from the tetrachloride:
IrCl4 ~ 2Li2S --~t IrS2 ~ 4I,lCl 2.00 gms of IrCl~ was dissolved in 175 ml of ethyl acetate.
~ . I .
~37~
The solution became dark brown. To this 0.55 gms of Li2S
was added neat with the color changing from a dark brown to golden. After stirring ~or 3.5 hours a golden powder was recovered, 1.8 gms of the product wa~ heat treated in 15~
H2S/N2 ~or 2 hour9, washed in 12% acetic acld then reheated in 15~ H2S/N2 ~or 2 hours yielding a black powder with a BET
surface area o 60 M2/gm, The acetic acid wash caused bubbling and fizzing whlch indicates lncomplete reaction of Li2S. As in the case of RuS2 prepared in H2S the product contained excess sulfur. X~ray powder diffraction yielded a very diffuse pattern probably of pyrite type IrS3. However, this compound reverted in the reactor to Ir metal ~ S .
4. Rhodium Rh2S3 was prepared in the same manner as in the previous examples from the trichloride: -2RhC13 + 3Li2S -,~Rh2S3 ~ 6LiCl X-ray analysis before and a~ter reaction indicated the pre sence o~ Rh2S3 which had a BET sur~ace area of 15 M2/gm.
5. Rhenium ~, ReS2 from ReC15 by the reac.tion.ReC15 ~ 2.5 Li2S > ~
~ . .
ReS2 ~ LiCl ~ .1/2 S
3,64 grams of ReC15 were reacted at room temperature with 2.30 gram~ of Li2S in 100 ml ethylacetate and stirred.
The black product was filtered and dried in H~S at 400 C.
The product analysis was ReS2 0:~
Theore tical Measured % Re 74~39 74.40 ~ S 25.61 25.49 X-rays indicated that the product corresponded to ReS2 and line broadenlng indicated a crystallite size of about 40 x 80A. The BET surface area was 50.2 m2~gm. Product before heat treatment was completeIy amorphous to X-rays, indicating ~ ~o~
crystalline oxder of le9s than 5~, thus an amorphous solid.
ReS2 from Re.C.14.by:thë r.e.a.cti.on Re.Cl.~. ~ .2 Li2S -~ReS2. ~ 4 LiCl In an exactly analogous manner, ReS2 was prepared from ReC14 at room temperature with the same results except that excess sulfur did not have to be removed by washing or heating. However, this product is considerably more active than that prepared from the pentachloride, in the hydro-sulfurization of dibenzothiophene (DBT).
~ . .
ReS2 ~ LiCl ~ .1/2 S
3,64 grams of ReC15 were reacted at room temperature with 2.30 gram~ of Li2S in 100 ml ethylacetate and stirred.
The black product was filtered and dried in H~S at 400 C.
The product analysis was ReS2 0:~
Theore tical Measured % Re 74~39 74.40 ~ S 25.61 25.49 X-rays indicated that the product corresponded to ReS2 and line broadenlng indicated a crystallite size of about 40 x 80A. The BET surface area was 50.2 m2~gm. Product before heat treatment was completeIy amorphous to X-rays, indicating ~ ~o~
crystalline oxder of le9s than 5~, thus an amorphous solid.
ReS2 from Re.C.14.by:thë r.e.a.cti.on Re.Cl.~. ~ .2 Li2S -~ReS2. ~ 4 LiCl In an exactly analogous manner, ReS2 was prepared from ReC14 at room temperature with the same results except that excess sulfur did not have to be removed by washing or heating. However, this product is considerably more active than that prepared from the pentachloride, in the hydro-sulfurization of dibenzothiophene (DBT).
6, ReS2 Dispersion 2.33 gram~ (8 mm) of ReC15 was added to 80 ml of propylene carbonate. To this was added 0.89 grams of Li2S
(19 mm) and the solution ~as stirred for 4 hours yielding a black liquid whlch was 0.lM in ReS2 and could be continuously diluted to any concentration. This black liquid passed through normal filter discs and was stable.
(19 mm) and the solution ~as stirred for 4 hours yielding a black liquid whlch was 0.lM in ReS2 and could be continuously diluted to any concentration. This black liquid passed through normal filter discs and was stable.
7. ReS2Gel , Theabove-described ReS2 dispersiorl gelled if the concentration was greater than ,033 M, upon standing for several days.
8. ReS2 Glass The above~described gel yielded a ~eS2 glass if the olvent was pumped off and the LiCl removed by washing with a suitable solvent (methanol).
9. ReS2/MgO Composi.tion _ _ , . . .
A 0.lM dispersion of ReS2 in propylene carbonate was prepared as described above. 25 ml of this dispersion was contacted with 4 grams of MgO and stirred for 4 hours.
The initially white solid was filtered and dried in H2S at 400C for 1 hour yielding a dark gray solid, The solid ReS2/MgO composite contained 2~33% Re. The amount of ReS2 - 1~3~
adsorbed on the MgO can be controlled by varying stirring time and concentration as shown in Figure II.
A 0.lM dispersion of ReS2 in propylene carbonate was prepared as described above. 25 ml of this dispersion was contacted with 4 grams of MgO and stirred for 4 hours.
The initially white solid was filtered and dried in H2S at 400C for 1 hour yielding a dark gray solid, The solid ReS2/MgO composite contained 2~33% Re. The amount of ReS2 - 1~3~
adsorbed on the MgO can be controlled by varying stirring time and concentration as shown in Figure II.
10. ReS~,/Al203 Composl,tion In a similar manner, ~4 grams of A12O3 was contact-ed with 114 ml of the 0.lM dispersion and stirred for 6 hours.
The dark gray ReS2/A12O3 contained 1.64% (wt) Re.
Platinum and Palla'di'um Both platinum and palladium were fairly inactive in hydrodesulfurization and thus their activities were not great-ly affected by method of preparation. Pd5 was prepared from the dichloride in a similar manner to the compounds previously described:
d 12 Li2 PdS -~ 2 LiCl PtS was prepared in this manner but was also prepared from the tetrachlorlde. This reaction led to chemical results differing from previous examples:
PtC14 + 2 Li2S aceYate ) PtS2 ~ 4 LiCl PtS2 ~ PtS
1.0 gm of PtC14 was dissolved in 200 ml of ethyl acetate and then divided into two samples. 100 ml was allowed to stand. Upon standing the solution began to darken and pre-cipitation began to occur. A golden film began to form as well as crystals. The crystals when examlned under polarized light were highly pleochroic transmitting light perpendicu-lar but not parallel to their long axis indicating the fox-mation of a Pt chain complex~ Preliminary chemical analysis indicates a-PtC14:LiCl:ethyl acetate complex.
Treatment of the remaining portion of the solution with Li25 as in previous examples yielded PtS after heat t~eating.
\~
~37~7S
TABLE I
_._ ___ Particle BET
t _ ucture hkl B Size A M2/gm~
OsS2 (Fresh) Layered 002 3.3 29 20 110 2.1 51 Os ~ S Metal 101 2.9 35 15 RuS2 Pyrite 200 1.2 90 52 h~S3 Rh2S3 200 0.6 162 15 lQ Irs2~x(Fresh) Pyrite 200? 7.0 14 73 Ir ~ S Metal 111 1.2 82 15 PdS Pds 200 0.3 324 PtS Cooperite 110 0.5 202 11 Ruthenlum, rhodium, iridium and osmium transition metal chalcogenides, preferably sulfides, prepared with high surface area as described herein, are excellent hydrodesulfur-ization, sulfur tolerant, hydrogenation and hydrodenitrogena-tion catalysts under typical conditions found in hydrofining processes of petroleum and coal based feedstocks. The Ru, :~
~h, Ir and Os sulfides are also effective as hydrogen-donor catalysts, i.e. they will abstract hydrogen from hydrogen- ~ -donor solvents like decalin, tetralin, etc. and use the abstracted hydrogen in the hydrosulfurization process.
The Ru, Rh, ~r and Os binary chalcogenides, preferably the sulfides, ef~ectively desulfurize DBT at elevated temperatures, e.g., 200-500C, and pressures accord-ing to the following reaction:
- ~13~2~5 1)~ + excess H2 Dibenzothiophene Biphenyl 5 wt. %
DBT BP
~3~`+ CrO
Cyclohexylbenzene Bicyclohexyl CHB BCH
The amount of CHB and BCH formed serves as a measure of the hydrogenation capabilities of these materials in sulfur environments. Tables I~ and III summarize the hydrodesulfur-ization and hydrogenation activity of the Group VIII metal sulfides.
.
, '':
~3'~275 TABLP II
HYDRODESULFURIZATION ACTIVIT~ OF GROUP VIII
TRANSITION METAL SULFIDES
... ., ..,., . .. ... . . _ _ Conditions: Carberry Reactor, 400C, 450 psi, 10~20 mesh catalyst particles Activity molecules DBT-~x Catalyst 1ol6- - -S -x ~ BP CHB
lG eS2_x 0~9 COgS8 1.6 NiS 1.6 RuS2 ~RUs2-x 210 20 RhSl 5 RhSl 5 x 70 PdS 9 OsS2--~SS2_~ 85 IrS2--~IrS2_x67 PtS -~ 7 TABLE III
HYDRODESULFURIZATION AND HYDROGENATION ACTIVITY
Conditions: Carberry Reactor, 350C, 450 psi, 20/40 mesh par~icles Activity molecules DBT-~x ~ ~:=
x ~ BP CHB
RUs2--~Rus2-x 113 24 RhSl 5t RhSl.5-x 10 OsS2-~ OsS2 x 40 17 I~S2-~IrS~ x 21 17 PtS -~ 4 0~4 - 21 ~
~372~5 These bulk sulfides will maintain their hydrode-sulfurization activity and hydrogenation activity for ex-tended periods of time in a flow reactor configuration under wide ranges of temperatures, pressures and liquid hourly space velocities. In act, when compared to a commercial Nalco cobalt molybdate on ~-A1203 (JCM-468) catalyst (CMA), several of the subject materials display comparable to super-ior activity per gram.
Table IV summarizes the flow reactor data obtained on RuS2 ~bulk) and where possible compares it to the commer-cial CMA catalyst described above. This binary sulfide maintained its activity over an extended period of 1053 hours (44 days).
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~7275 The Group VIII transition metal chalcogenides, preferably sulfides, prepared via nonaqueous dispersions on supports described herein are active hydrodesulfurization, hydrogenation and hydrodenitrogenation catalysts and are often ~uperlor to prior art materials. For comparative purpo~es the materials were prepared by the following techniques:
5upport ) 4 i2 ~ MS2/Support Slurry Propylene Carbonate 3) Support Aqueous Dry 80~100C Presulfide Impregnation Incipient wt- Vacuum Oven 15~ H2S/H2 ness of water 12 hrs.25-400C
soluble salt 2 hrs.
4) Support Aqueous Dry 80- Reduce Presulfide Impregnation 100C in H2 Incipient wet- Vacuum 500C 15% H2S/H2 ness of water Oven - 1-4 ~rs 25~40~C
soluble salt 12 Hrs 2 hrs.
The hydrodesulfurization of supported ruthenium catalysts i~ c~mpared on a per gram and per millimole Ru basis in Tables V and VI. Table V indicates that RuS2 supported on MgO, Material 1, prepared with the nonaqueous dispersion, displays superior activity compared to prior art Materials 2 and 3.
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~1 ~L137~75 Table VI provides additional data indicating that supported Group VIII chalcogenides prepared via nonaqueous dispersion techniques, are superior HDS catalysts compared to prior art materials, i.eO Material 2 is superior to prior art Materials 3 and 4; Material 5 is superior to prior art Material 6. In addition, Table VI demonstrates that Group VIII chalcogenides supported on a basic support such as MgO
via dispersion techniques are superior to other dispersion supported materials: Material 1, RuS2/MgO is a much better HDS catalyst per gram and per millimole of Ru than Materials 2, 5, or 7.
~ 26 -;
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ReS2 supported on a basic oxide such as MgO pre-pared according to the following procedure, i5 an active and selective HDS catalyst for resid-like organosulfur mole-cules, i.e. DBT.
Slurried in Li S
ReC5 ~ ~g ~---~~~~~~`~ ) ~ ReS~/MgO
Propylene Stir ~ LiCl Carbonate 4 hrs. @ (Solvent) room temp.
ReS2~MgO ~ ReS2 (1-10% Re)/MgO
1 hr.
Table VIl presents the data obtained at 400C and 450 psig., H2 flow AV 100 cc/min.
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is approximately as active as CMA at a space velocity equal to 1 V/V/H. ~Iowever, Re52/MgO is much more selective toward desulfurizati.on as evidenced by the selectivity factors.
Consequently, under conditions necessary to desulfurize resid., i.e. T = 400C, P~ 450 psig, 9V = 0.5-l ~/V~H, ReS2/MgO is as active (on mole % conversion basis) as CMA
but is far more selective.
TABLE V}I}
HYDRODESULFURIZATION ACTIVITY OF GROUP VIII
BINARY_SULFIDES VIA HYDROGEN DONOR REACTIONS
Conditions: Carberry Reactor, 450 psi, He at-mosphere. ~ecalin serves as hydrogen source.
16 Activity Temp. Par~icle rxlO Molecules DBT-~BP
y~ __ CSize, Mesh _ gm-sec RuS2-~RuS2_x 35010/20 14 OsS2~ OsS2 x 40020/40 23 A ~
The bulk and supported ~roup VIII transition metal chalcogenides, preferably sulfides, described herein are active HDN catalysts for the removal of organic nitrogen from petroleum, shale and coal based feedstocks.
Table IX summari~es some typical results which reflect the HD~ activity of th0se materials using a model organonitrogen compound, quinoline. The degree of nitrogen removal was followed analytically by determining the nitrogen content of the feed (ppm) before and after contact with the catalyst in a high pressure and temperature flow reactor.
These materials will be effective denitrogenation catalysts over a range of temperatures~ e.g., 250-500C, hydrogen pressures and space velocities.
1~3~Z7~ii TABLE IX
H~DRODENITROGENATION ACTIVIT~ OF GROUP VIII
CH~LCO~EN~DES
Condltions: High Pressure Flow Reactor;
Feed: .8% S, .099~ N in decalin (S as DBT, N as quinoline) T-280C, P=450 psi, LHSV= 1.3 ~ % N i~ Feed % N in Product ~ HDN
RuS2 0.099 0.013 87 - 31 ~
The dark gray ReS2/A12O3 contained 1.64% (wt) Re.
Platinum and Palla'di'um Both platinum and palladium were fairly inactive in hydrodesulfurization and thus their activities were not great-ly affected by method of preparation. Pd5 was prepared from the dichloride in a similar manner to the compounds previously described:
d 12 Li2 PdS -~ 2 LiCl PtS was prepared in this manner but was also prepared from the tetrachlorlde. This reaction led to chemical results differing from previous examples:
PtC14 + 2 Li2S aceYate ) PtS2 ~ 4 LiCl PtS2 ~ PtS
1.0 gm of PtC14 was dissolved in 200 ml of ethyl acetate and then divided into two samples. 100 ml was allowed to stand. Upon standing the solution began to darken and pre-cipitation began to occur. A golden film began to form as well as crystals. The crystals when examlned under polarized light were highly pleochroic transmitting light perpendicu-lar but not parallel to their long axis indicating the fox-mation of a Pt chain complex~ Preliminary chemical analysis indicates a-PtC14:LiCl:ethyl acetate complex.
Treatment of the remaining portion of the solution with Li25 as in previous examples yielded PtS after heat t~eating.
\~
~37~7S
TABLE I
_._ ___ Particle BET
t _ ucture hkl B Size A M2/gm~
OsS2 (Fresh) Layered 002 3.3 29 20 110 2.1 51 Os ~ S Metal 101 2.9 35 15 RuS2 Pyrite 200 1.2 90 52 h~S3 Rh2S3 200 0.6 162 15 lQ Irs2~x(Fresh) Pyrite 200? 7.0 14 73 Ir ~ S Metal 111 1.2 82 15 PdS Pds 200 0.3 324 PtS Cooperite 110 0.5 202 11 Ruthenlum, rhodium, iridium and osmium transition metal chalcogenides, preferably sulfides, prepared with high surface area as described herein, are excellent hydrodesulfur-ization, sulfur tolerant, hydrogenation and hydrodenitrogena-tion catalysts under typical conditions found in hydrofining processes of petroleum and coal based feedstocks. The Ru, :~
~h, Ir and Os sulfides are also effective as hydrogen-donor catalysts, i.e. they will abstract hydrogen from hydrogen- ~ -donor solvents like decalin, tetralin, etc. and use the abstracted hydrogen in the hydrosulfurization process.
The Ru, Rh, ~r and Os binary chalcogenides, preferably the sulfides, ef~ectively desulfurize DBT at elevated temperatures, e.g., 200-500C, and pressures accord-ing to the following reaction:
- ~13~2~5 1)~ + excess H2 Dibenzothiophene Biphenyl 5 wt. %
DBT BP
~3~`+ CrO
Cyclohexylbenzene Bicyclohexyl CHB BCH
The amount of CHB and BCH formed serves as a measure of the hydrogenation capabilities of these materials in sulfur environments. Tables I~ and III summarize the hydrodesulfur-ization and hydrogenation activity of the Group VIII metal sulfides.
.
, '':
~3'~275 TABLP II
HYDRODESULFURIZATION ACTIVIT~ OF GROUP VIII
TRANSITION METAL SULFIDES
... ., ..,., . .. ... . . _ _ Conditions: Carberry Reactor, 400C, 450 psi, 10~20 mesh catalyst particles Activity molecules DBT-~x Catalyst 1ol6- - -S -x ~ BP CHB
lG eS2_x 0~9 COgS8 1.6 NiS 1.6 RuS2 ~RUs2-x 210 20 RhSl 5 RhSl 5 x 70 PdS 9 OsS2--~SS2_~ 85 IrS2--~IrS2_x67 PtS -~ 7 TABLE III
HYDRODESULFURIZATION AND HYDROGENATION ACTIVITY
Conditions: Carberry Reactor, 350C, 450 psi, 20/40 mesh par~icles Activity molecules DBT-~x ~ ~:=
x ~ BP CHB
RUs2--~Rus2-x 113 24 RhSl 5t RhSl.5-x 10 OsS2-~ OsS2 x 40 17 I~S2-~IrS~ x 21 17 PtS -~ 4 0~4 - 21 ~
~372~5 These bulk sulfides will maintain their hydrode-sulfurization activity and hydrogenation activity for ex-tended periods of time in a flow reactor configuration under wide ranges of temperatures, pressures and liquid hourly space velocities. In act, when compared to a commercial Nalco cobalt molybdate on ~-A1203 (JCM-468) catalyst (CMA), several of the subject materials display comparable to super-ior activity per gram.
Table IV summarizes the flow reactor data obtained on RuS2 ~bulk) and where possible compares it to the commer-cial CMA catalyst described above. This binary sulfide maintained its activity over an extended period of 1053 hours (44 days).
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~7275 The Group VIII transition metal chalcogenides, preferably sulfides, prepared via nonaqueous dispersions on supports described herein are active hydrodesulfurization, hydrogenation and hydrodenitrogenation catalysts and are often ~uperlor to prior art materials. For comparative purpo~es the materials were prepared by the following techniques:
5upport ) 4 i2 ~ MS2/Support Slurry Propylene Carbonate 3) Support Aqueous Dry 80~100C Presulfide Impregnation Incipient wt- Vacuum Oven 15~ H2S/H2 ness of water 12 hrs.25-400C
soluble salt 2 hrs.
4) Support Aqueous Dry 80- Reduce Presulfide Impregnation 100C in H2 Incipient wet- Vacuum 500C 15% H2S/H2 ness of water Oven - 1-4 ~rs 25~40~C
soluble salt 12 Hrs 2 hrs.
The hydrodesulfurization of supported ruthenium catalysts i~ c~mpared on a per gram and per millimole Ru basis in Tables V and VI. Table V indicates that RuS2 supported on MgO, Material 1, prepared with the nonaqueous dispersion, displays superior activity compared to prior art Materials 2 and 3.
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~1 ~L137~75 Table VI provides additional data indicating that supported Group VIII chalcogenides prepared via nonaqueous dispersion techniques, are superior HDS catalysts compared to prior art materials, i.eO Material 2 is superior to prior art Materials 3 and 4; Material 5 is superior to prior art Material 6. In addition, Table VI demonstrates that Group VIII chalcogenides supported on a basic support such as MgO
via dispersion techniques are superior to other dispersion supported materials: Material 1, RuS2/MgO is a much better HDS catalyst per gram and per millimole of Ru than Materials 2, 5, or 7.
~ 26 -;
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ReS2 supported on a basic oxide such as MgO pre-pared according to the following procedure, i5 an active and selective HDS catalyst for resid-like organosulfur mole-cules, i.e. DBT.
Slurried in Li S
ReC5 ~ ~g ~---~~~~~~`~ ) ~ ReS~/MgO
Propylene Stir ~ LiCl Carbonate 4 hrs. @ (Solvent) room temp.
ReS2~MgO ~ ReS2 (1-10% Re)/MgO
1 hr.
Table VIl presents the data obtained at 400C and 450 psig., H2 flow AV 100 cc/min.
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.
_ ~ t`N .--1 . . I ,.
~, ~1 o t~
~ ~ O
_ ~1 ~ Iq a) _~
C) ~ ~ +
C) ~ U~ ~ .
_ f~ 1 l 4 P
~_ m m 6P o'P
o _, ~ ~ ~ ~o r~
U~
"~ ~: ~ U~
C~ C~ ~;
., -- 23 ~, 1~37~75 Table VI~ indicates that under comparable conditions but with lower metal loading and less catalyst, ReS2 (2.1~ Re)/MgO
is approximately as active as CMA at a space velocity equal to 1 V/V/H. ~Iowever, Re52/MgO is much more selective toward desulfurizati.on as evidenced by the selectivity factors.
Consequently, under conditions necessary to desulfurize resid., i.e. T = 400C, P~ 450 psig, 9V = 0.5-l ~/V~H, ReS2/MgO is as active (on mole % conversion basis) as CMA
but is far more selective.
TABLE V}I}
HYDRODESULFURIZATION ACTIVITY OF GROUP VIII
BINARY_SULFIDES VIA HYDROGEN DONOR REACTIONS
Conditions: Carberry Reactor, 450 psi, He at-mosphere. ~ecalin serves as hydrogen source.
16 Activity Temp. Par~icle rxlO Molecules DBT-~BP
y~ __ CSize, Mesh _ gm-sec RuS2-~RuS2_x 35010/20 14 OsS2~ OsS2 x 40020/40 23 A ~
The bulk and supported ~roup VIII transition metal chalcogenides, preferably sulfides, described herein are active HDN catalysts for the removal of organic nitrogen from petroleum, shale and coal based feedstocks.
Table IX summari~es some typical results which reflect the HD~ activity of th0se materials using a model organonitrogen compound, quinoline. The degree of nitrogen removal was followed analytically by determining the nitrogen content of the feed (ppm) before and after contact with the catalyst in a high pressure and temperature flow reactor.
These materials will be effective denitrogenation catalysts over a range of temperatures~ e.g., 250-500C, hydrogen pressures and space velocities.
1~3~Z7~ii TABLE IX
H~DRODENITROGENATION ACTIVIT~ OF GROUP VIII
CH~LCO~EN~DES
Condltions: High Pressure Flow Reactor;
Feed: .8% S, .099~ N in decalin (S as DBT, N as quinoline) T-280C, P=450 psi, LHSV= 1.3 ~ % N i~ Feed % N in Product ~ HDN
RuS2 0.099 0.013 87 - 31 ~
Claims (17)
OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. Chalcogenides which are amorphous to x-ray and having a particle size of less than 0.1 micron and a crystallite size of about 50°A x 100°A or less of the formula MXy wherein M is ruthenium, rhodium, iridium or osmium, X is a chalcogenide selected from the group consisting of sulfur, selenium, teller-ium and mixtures thereof, and y is a number ranging from about 0.1 to about 3 or M is technetium, rhenium or manganese and y is about 1.5 to about 4.
2. Chalcogenides which are amorphous to x-ray and of the formula MXy, M being defined as a metal selected from the group consisting of ruthenium, rhodium, iridium and osmium, X
being a chalcogenide selected from the group consisting of sul-fur, selenium, tellurium and mixtures thereof, and y a number ranging from about 0.1 to about 3, or M being technetium, rhen-ium or manganese and y about 1.5 to about 4, prepared by mixing in the absence of aqueous or protic solvent:
(a) salts of metal M, the anion of the salt being selected from the group consisting of halide, acetate, car-boxylates, perfluorocarboxylates, acetylacetonates, hexa-fluoroacetylacetonates, sulfates and nitrates wherein the carbonaceous moiety of the anion is a C1 to C8 hydrocarbon or fluorocarbon, and (b) sources of sulfide, selenide or telluride ions and mixtures thereof selected from the group consisting of Li2X, Na2X, K2X, KHX, NaHX, (NH4)2X, (RNH3)2X, (RR'NH2)2X, LiHX, (RR'R"NH)2X, wherein R, R' and R" are the same or dif-ferent C1 to C20 alkyl or C6 to C20 aryl, at a temperature of between 0° to 400°C.
being a chalcogenide selected from the group consisting of sul-fur, selenium, tellurium and mixtures thereof, and y a number ranging from about 0.1 to about 3, or M being technetium, rhen-ium or manganese and y about 1.5 to about 4, prepared by mixing in the absence of aqueous or protic solvent:
(a) salts of metal M, the anion of the salt being selected from the group consisting of halide, acetate, car-boxylates, perfluorocarboxylates, acetylacetonates, hexa-fluoroacetylacetonates, sulfates and nitrates wherein the carbonaceous moiety of the anion is a C1 to C8 hydrocarbon or fluorocarbon, and (b) sources of sulfide, selenide or telluride ions and mixtures thereof selected from the group consisting of Li2X, Na2X, K2X, KHX, NaHX, (NH4)2X, (RNH3)2X, (RR'NH2)2X, LiHX, (RR'R"NH)2X, wherein R, R' and R" are the same or dif-ferent C1 to C20 alkyl or C6 to C20 aryl, at a temperature of between 0° to 400°C.
3. Chalcogenides prepared as in claim 2, further comprising the use of a nonaqueous solvent.
4. Chalcogenides prepared as in claim 2 or 3 wherein X is sulfur.
5. A method for the preparation of chalcogenides which are amorphous to x-ray of the formula MXy, M being defined as ruthenium, rhodium, iridium or osmium, X being sulfur, selenium, tellurium or mixtures thereof, and y a number ranging from about 0.1 to about 3, or M being mang-anese, technetium or rhenium and y about 1.5 to about 4, which comprises reacting in the absence of aqueous or protic solvent, a salt of the metal M, the anion of the salt being selected from the group consisting of halide, acetate, car-boxylate, perfluorocarboxylate, acetylacetonates and hexa-fluoroacetylacetonates, sulfates and nitrates wherein the carbonaceous moiety of the anion is a C1-C8 hydrocarbon or fluorocarbon, with a source of sulfide, selenide or telluride ions selected from the group consisting of K2X, Li2X, HX-, (NH4)2X, Na2X, (RNH3)2X, (R,R'NH2)2X, (R,R'R"NH)2X wherein R, R' and R" are the same or different C1-C20 alkyl or C6-C20 aryl, at a temperature of from 0° to 400°C.
6. The method of claim 5 further characterized by using a nonaqueous aprotic solvent.
7. The method of claim 6 wherein the nonaqueous aprotic solvent is selected from the group consisting of ace-tonitrile, benzonitrile, propionitrile, acetone. C1-C20 alkyl-halide, C6-C20 arylhalide, 1,2 dimethoxyethane, diglyme, N-methylformamide, dimethylformamide, C6-C20 aromatics, pyridine, C1-C12 alkanes, C4-C8 ethers, anhydrous acids, C4-C8 esters, propylene carbonate.
8. The method of claim 5 further characterized by the step of contacting the isolated product with an in-tercalating solvent, thereby forming an intercalated chal-cogenide and then driving the solvent off by means of heat, thereby generating a chalcogenide of increased surface area.
9. The method of claim 8 wherein the intercalat-ing solvent is selected from the group consisting of pyri-dine, ammonia, C1-C20 amines, aldehydes, ketones, amides, heterocyclic bases, and amidines, and the solvent is subse-quently driven off at a temperature of between 75-200°C.
10. The method of claim 5 wherein the product is a stoichiometric chalcogenide.
11. The method of claim 5 wherein x is sulfur.
12. The method of claim 5 wherein the tempera-ture of reaction is between 25° to 300°C.
13. The method of claim 5 wherein the product is a disulfide.
14. The method of claim 5 wherein M is manganese, technetium or rhenium, further characterized by including the step of annealing the isolated product at a temperature of over about 450°C thereby generating a product having low surface area, moderate particle size and high crystallinity.
15. Homogenous dispersions of compositions as set forth in claim 1 or 2 in solvents selected from the group consisting of propylene carbonate, dimethylformamide, pyridine, acetonitrile, benzonitrile, propionitrile, 1,2 dimethoxyethane, diglyme, N-methylformamide.
16. Homogenous dispersions of compositions as set forth in claim 1 or 2 in solvents selected from the group consisting of propylene carbonate, dimethylformamide, pyridine, acetonitrile, benzonitrile, propionitrile, 1,2 dimethoxyethane, diglyme, N-methylformamide and wherein the compound dispersed is ReS2.
17. Compositions comprising homogenous dispersions of compositions as set forth in claim 1 or 2 in solvents selected from the group consisting of propylene carbonate, dimethylformamide, pyridine, acetonitrile, benzonitrile, prop-ionitrile, 1,2 dimethoxyethane, diglyme, N-methylformamide deposited on high surface area supports, said supports being carbon or refractory oxides.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US79701377A | 1977-05-16 | 1977-05-16 | |
| US79701177A | 1977-05-16 | 1977-05-16 | |
| US797,011 | 1977-05-16 | ||
| US797,013 | 1977-05-16 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1137275A true CA1137275A (en) | 1982-12-14 |
Family
ID=27121818
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000302783A Expired CA1137275A (en) | 1977-05-16 | 1978-05-08 | Chalcogenides of groups viii and viib |
Country Status (4)
| Country | Link |
|---|---|
| JP (1) | JPS53142397A (en) |
| CA (1) | CA1137275A (en) |
| DE (1) | DE2821224A1 (en) |
| FR (1) | FR2391155A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8999877B2 (en) | 2007-09-14 | 2015-04-07 | Toyota Jidosha Kabushiki Kaisha | Single-crystal fine powder of sulfide or sulfide complex and method for preparing the same |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3223501C1 (en) * | 1982-06-24 | 1985-12-12 | Degussa Ag, 6000 Frankfurt | Process for the extraction of precious metals from solutions |
| JP4843568B2 (en) * | 2007-06-28 | 2011-12-21 | 株式会社クラレ | Method for producing iridium sulfide |
-
1978
- 1978-05-08 CA CA000302783A patent/CA1137275A/en not_active Expired
- 1978-05-12 FR FR7814209A patent/FR2391155A1/en active Granted
- 1978-05-16 JP JP5813378A patent/JPS53142397A/en active Pending
- 1978-05-16 DE DE19782821224 patent/DE2821224A1/en not_active Withdrawn
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8999877B2 (en) | 2007-09-14 | 2015-04-07 | Toyota Jidosha Kabushiki Kaisha | Single-crystal fine powder of sulfide or sulfide complex and method for preparing the same |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS53142397A (en) | 1978-12-12 |
| FR2391155B1 (en) | 1985-02-08 |
| DE2821224A1 (en) | 1978-11-30 |
| FR2391155A1 (en) | 1978-12-15 |
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