Patents by Inventor Gopal H. Singhal
Gopal H. Singhal has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 5294349Abstract: A process for hydroprocessing coal to hydrocarbon oils wherein coal is depolymerized at low temperatures by contacting finely divided coal with a hard acid and soft base. The depolymerized coal is then hydroprocessed to hydrocarbon oils by forming a mixture with a coal conversion catalyst or precursor thereof, and hydroprocessing the mixture at temperatures of from 250.degree. to 550.degree. C. and hydrogen partial pressures of from 2100 to 35000 kPa.Type: GrantFiled: August 4, 1992Date of Patent: March 15, 1994Assignee: Exxon Research and Enginnering CompanyInventors: George M. Kramer, Edwin R. Ernst, Chang S. Hsu, Gopal H. Singhal, Peter S. Maa
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Patent number: 5278121Abstract: The present invention relates to novel catalysts for removing heteroatoms, particularly nitrogen, from hydrocarbonaceous feedstocks. The catalysts are comprised of highly dispersed molybdenum sulfide promoted with a noble metal such that the noble metal is in an oxidation state greater than 0 and coordinated to S. The noble metal is selected from Pt, Pd, Rh, and Ir. It is preferred that the catalysts of be prepared from a precursor composition selected from platinum ethoxyethyl xanthate or platinum dithiocarbamate. Additionally, the catalyst may include a promotor sulfide such as nickel sulfide, cobalt sulfide or iron sulfide, etc. or mixtures thereof.Type: GrantFiled: March 31, 1992Date of Patent: January 11, 1994Assignee: Exxon Research & Engineering CompanyInventors: Gopal H. Singhal, Leo D. Brown, X. B. Cox, III, Thomas R. Halbert
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Patent number: 5086027Abstract: A catalyst composition comprised of: about 0.005 to 5.0 wt. % noble metal, about 0.5 to 5 wt. % of at least one Group VIII metal, and about 3 to 18 wt. % of a Group VI metal, and a refractory support, wherein the noble metal is incorporated into the refractory support by use of a precursor represented by ML.sub.2 when the noble metal is Pt or Pd and ML.sub.3, when the noble metal is Rh or Ir, where M is the noble metal and L is a ligand selected from the dithiocarbamates, dithiophosphates, dithiophosphinates, xanthates, thioxanthates, and further wherein L has organo groups having a sufficient number of carbon atoms to render the noble metal complex soluble in oil.Type: GrantFiled: December 18, 1990Date of Patent: February 4, 1992Assignee: Exxon Research and Engineering CompanyInventors: Gopal H. Singhal, William E. Winter, Kenneth L. Riley, Kenneth L. Trachte
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Patent number: 5064527Abstract: An improved hydroconversion process for carbonaceous materials wherein a dihydrocarbyl substituted dithiocarbamate of a metal selected from any one of Groups IV-B, V-A, VI-A, VII-B, and VIII-A of the Periodic Table of Elements or a mixture thereof is used as a catalyst precursor. The improved process is effective for both normally solid and normally liquid carbonaceous materials and for carbonaceous materials which are either solid or liquid at the conversion conditions. The hydroconversion will be accomplished at a temperature within the range from about 500.degree. to about 900.degree. F., at a total pressure within the range from about 500 to 7000 psig and at a hydrogen partial pressure within the range from about 400 to about 5000 psig.Type: GrantFiled: May 8, 1984Date of Patent: November 12, 1991Assignee: Exxon Research & Engineering CompanyInventors: Gopal H. Singhal, Bobby L. Wilson, Edward H. Edelson, Michael A. Mikita
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Patent number: 5055211Abstract: The addition of certain mixed ligand metal complexes and a metal thiophosphate to a lubricating oil results in a significant improvement in the anti-wear performance of the oil. Tin dithiocarbamate-ethoxyethylxanthate and zinc dialkyldithiophosphate are preferred additives.Type: GrantFiled: September 7, 1989Date of Patent: October 8, 1991Assignee: Exxon Research and Engineering CompanyInventors: Jacob J. Habeeb, Gopal H. Singhal
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Patent number: 5035815Abstract: The addition of a metal alkoxyalkylxanthate and a metal thiophosphate to a lubricating oil results in an unexpected synergistic improvement in the antiwear performance of the oil. Nickel ethoxyethylxanthate and zinc dialkyldithiophosphate are most preferred additives.Type: GrantFiled: September 7, 1989Date of Patent: July 30, 1991Assignee: Exxon Research and Engineering CompanyInventors: Jacob J. Habeeb, Gopal H. Singhal, Rustom M. Billimoria, William H. Stover
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Patent number: 5034142Abstract: The addition of a metal alkoxyalkylxanthate, a dixanthogen, and a metal thiophosphate to a lubricating oil results in a synergistic improvement in the antiwear performance of the oil. Nickel ethoxyethylxanthate, diethoxyethyl dixanthogen, and zinc dialkyldithiophosphate are particularly preferred additives.Type: GrantFiled: September 7, 1989Date of Patent: July 23, 1991Assignee: Exxon Research and Engineering CompanyInventors: Jacob J. Habeeb, Gopal H. Singhal
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Patent number: 5026492Abstract: The addition of an alkyl alkoxyalkylxanthate and a metal thiophosphate to a lubricating oil results in an unexpected synergistic improvement in the antiwear performance of the oil. Butyl ethoxyethylxanthate and zinc dialkyldithiophosphate are most preferred additives.Type: GrantFiled: September 7, 1989Date of Patent: June 25, 1991Assignee: Exxon Research & Engineering CompanyInventors: Gopal H. Singhal, Jacob J. Habeeb
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Patent number: 4853110Abstract: A process for removing arsenic and/or selenium from carbonaceous materials. The arsenic and/or selenium are separated by reaction with a metal oxide and/or metal sulfide which is itself derived from a metal complex, and organometallic compound and/or a metal salt of an organic acid which is soluble in said carbonaceous fluid and which either decomposes to the corresponding metal oxide and/or metal sulfide or which can be converted to the corresponding metal sulfide or metal oxide. The reaction of the metal oxide and/or metal sulfide with the arsenic and/or selenium is accomplished at a temperature within the range from about 300.degree. F. to about 800.degree. F. preferably from about 500.degree. F. to about 750.degree. F., most preferably from about 680.degree. F. to about 750.degree. F. and in either an inert or reducing atmosphere. Preferably, the conversion is accomplished in a reducing atmosphere and in the presence of molecular hydrogen.Type: GrantFiled: October 31, 1986Date of Patent: August 1, 1989Assignee: Exxon Research and Engineering CompanyInventors: Gopal H. Singhal, Daniel F. Ryan
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Patent number: 4824558Abstract: An improved process for hydroconverting carbonaceous material wherein the hydroconversion is accomplished in the presence of a sulfide of tin or tin and at least one metal selected from the Group of metals consisting of the Groups IV-B, V-A, VI-A, VII-A and Group VIII-A metals of the Periodic Table of the Elements and in the presence of iodine. The tin and any other metal may be added directly as the sulfide or as a soluble precursor that will either decompose or be converted to the sulfide. The iodine may be added directly as iodine, hydrogen iodine or as a precursor which will decompose to yield either iodine or hydrogen iodide. The hydroconversion is also accomplished in the presence of hydrogen.Type: GrantFiled: September 4, 1987Date of Patent: April 25, 1989Assignee: Exxon Research and Engineering CompanyInventors: Peter S. Maa, Lonnie W. Vernon, William E. Winter, Gopal H. Singhal
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Patent number: 4683316Abstract: An improved process for preparing dihydrocarbyl substituted dithiocarbamates of molybdenum (VI) wherein an alkali metal ammonium or substituted ammonium salt of a dihydrocarbyl substituted dithiocarbamate is reacted with an alkali metal molybdate in the presence of an organic acid. The process is carried out in an inert atmosphere and within a relatively narrow range of temperatures. The dihydrocarbyl substituted dithiocarbamate of molybdenum (VI) may be recrystallized after preparation to increase its purity. The dihydrocarbyl substituted dithiocarbamate of molybdenum (VI) is produced at a temperature within the range from about -10.degree. C. to about +25.degree. C. at a pH during neutralization within the range from about 5.0 to about 8.0.Type: GrantFiled: January 2, 1986Date of Patent: July 28, 1987Assignee: Exxon Research and Engineering CompanyInventor: Gopal H. Singhal
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Patent number: 4681957Abstract: An improved process for preparing dihydrocarbyl substituted dithiocarbamates of molybdenum wherein an alkali metal hydroxide is reacted with a mixture of a dihydrocarbyl substituted amine and carbon disulfide in an aqueous solution to produce an alkali metal salt of dithiocarbamate and the alkali metal salt then reacted with an alkali metal molybdate in the presence of acid to produce the dihydrocarbyl substituted dithiocarbamate of molybdenum. The process is completed in an inert atmosphere and within a relatively narrow range of temperatures so as to avoid the production of by-products which have heretofore reduced both the yield and purity of the final product. The preparation of the alkali metal salt of dithiocarbamate is completed at a temperature generally within the range from about -5 to about 30.degree. C. The acidification of the alkali metal salt of dithiocarbamate is completed, generally, at a temperature within the range from about -5 to about 5.degree. C.Type: GrantFiled: September 3, 1985Date of Patent: July 21, 1987Assignee: Exxon Research and Engineering CompanyInventors: Gopal H. Singhal, Claude C. Culross
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Patent number: 4561964Abstract: An improved hydroconversion process for carbonaceous materials wherein a monohydrocarbyl substituted dithiocarbamate of a metal selected from Group VIII-A of the Periodic Table of Elements or a mixture thereof is used as a catalyst precursor. The improved process is effective for both normally solid and normally liquid carbonaceous materials and for carbonaceous materials which are either solid or liquid at the conversion conditions. The hydroconversion will be accomplished at a temperature within the range from about 500.degree. to about 900.degree. F., at a total pressure within the range from about 500 to 7000 psig and at a hydrogen partial pressure within the range from about 400 to about 5000 psig.Type: GrantFiled: October 1, 1984Date of Patent: December 31, 1985Assignee: Exxon Research and Engineering Co.Inventors: Gopal H. Singhal, Karla S. Colle, Edward H. Edelson, Bobby L. Wilson, Loan H. Dao
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Patent number: 4454024Abstract: A slurry hydroconversion process is provided wherein a heavy hydrocarbonaceous oil, in which is dispersed a metal-contaminated, partially deactivated zeolitic cracking catalyst, is converted to lower boiling products in the presence of a molecular hydrogen-containing gas, and a hydrogen donor diluent.Type: GrantFiled: November 1, 1982Date of Patent: June 12, 1984Assignee: Exxon Research and Engineering Co.Inventors: Gopal H. Singhal, Gordon F. Stuntz
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Patent number: 4434043Abstract: Metal constituents are recovered from the heavy bottoms produced during the liquefaction of coal and similar carbonaceous solids in the presence of a catalyst containing metal constituents by reducing the carbonaceous content of the heavy bottoms, contacting the resultant heavy bottoms deficient in carbonaceous material with an aqueous solution of a mineral acid in the presence of an added alcohol and an added oxidizing agent to extract the metal constituent from the insoluble catalyst residues into the aqueous solution, and using the metal constituents extracted as constituents of the catalyst. Preferably, the metal constituent comprising the catalyst is molybdenum, the mineral acid is sulphuric acid, hydrochloric acid or phosphoric acid, the oxidizing agent is hydrogen peroxide and the alcohol is methanol.Type: GrantFiled: June 1, 1982Date of Patent: February 28, 1984Assignee: Exxon Research and Engineering Co.Inventors: Gopal H. Singhal, Ramachandra A. Nadkarni
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Patent number: 4272401Abstract: Contacting deactivated hydrodesulfurization catalyst, such as Co-Mo supported on alumina, with a heteropoly acid, such as molybdophosphoric acid or tungstosilicic acid, in pH range of about 1 to 3 and temperature range of about 20.degree. to 80.degree. C., results, before any coke is burned off the catalyst, in selective abstraction of vanadium and nickel, removal of sulfur, increase in surface area, and increase in pore volume of the catalyst. Subsequent cobalt doping of demetallized catalyst followed by calcination promotes decoking, additional sulfur removal and additional increase in surface area and pore volume. The process results in substantially complete regeneration of catalytic activity.Type: GrantFiled: July 19, 1979Date of Patent: June 9, 1981Assignee: Exxon Research & Engineering Co.Inventors: Raam R. Mohan, Gopal H. Singhal
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Patent number: 4272400Abstract: The removal of metals, especially vanadium, from spent hydrofining catalyst is accomplished by a two-step process. Treatment with a gaseous sulfur-containing reagent brings the metals to the surface of the catalyst and converts them to sulfides, which are then efficiently removed by contact with a heteropoly acid such as molybdophosphoric acid. Treatment of deactivated hydrodesulfurization catalysts such as Co-Mo supported on alumina by this process results in substantially complete regeneration of catalytic activity.Type: GrantFiled: July 19, 1979Date of Patent: June 9, 1981Assignee: Exxon Research & Engineering Co.Inventors: Bernard G. Silbernagel, Raam R. Mohan, Gopal H. Singhal
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Patent number: 4268415Abstract: Contacting deactivated hydrodesulfurization catalyst, such as Co-Mo supported on alumina, with a heteropoly acid, such as molybdophosphoric acid or tungstosilicic acid, to which dilute hydrogen peroxide is added, results in a significant enhancement in the rate and extent of carbon and metals removal. Forms of deposited vanadium intractable by other treatments are also removed. The process results in substantially complete regeneration of catalytic activity.Type: GrantFiled: July 19, 1979Date of Patent: May 19, 1981Assignee: Exxon Research & Engineering Co.Inventors: Raam R. Mohan, Bernard G. Silbernagel, Gopal H. Singhal
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Patent number: 4064040Abstract: This invention relates to novel liquid membrane formulations which are water-in-oil emulsions wherein the oil phase comprises a sulfonated polymer having a backbone which is substantially nonaromatic, for example, less than 10 mole % aromatic, and uses thereof in high temperature liquid membrane processes. The emulsions are useful in liquid membrane water treating processes, especially in water treating processes which are desirably run at high temperatures. In the most preferred embodiment, these compositions are used in a liquid membrane sour water treating process wherein a waste water stream containing ammonium sulfide is contacted with a liquid membrane emulsion, i.e. the emulsions of the instant invention, at conditions whereby ammonia permeates through the external phase of the emulsion into an acidic internal phase wherein it is converted to a nonpermeable form, e.g. ammonium ion, while H.sub.2 S is continuously stripped out of the waste water solution by means of an inert gas, e.g. steam.Type: GrantFiled: May 3, 1976Date of Patent: December 20, 1977Assignee: Exxon Research & Engineering Co.Inventors: Gopal H. Singhal, Martin L. Gorbaty, Richard M. Minday, Norman N. Li
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Patent number: 4014785Abstract: The instant invention relates to novel liquid membrane formulations, i.e., emulsions, which comprise an aqueous interior phase and a water-immiscible exterior phase; said water-immiscible exterior phase comprising an ethylene vinyl acetate copolymer and a solvent for this polymer. These compositions may additionally contain a water insoluble surfactant to stabilize the emulsions. In the most preferred embodiment, the aqueous interior phase comprises a strong acid, for example from about 1 to 10 percent by weight sulfuric acid. These emulsions are useful in liquid membrane processes for the separation of dissolved components from aqueous solution. Emulsions of the instant invention are characterized as showing very low swelling when contacted with aqueous solutions, especially at higher temperatures and thus are especially effective for use in the treatment of sour water feed streams by the liquid membrane technique.Type: GrantFiled: October 9, 1975Date of Patent: March 29, 1977Assignee: Exxon Research and Engineering CompanyInventors: Norman N. Li, Gopal H. Singhal, Richard M. Minday, Martin L. Gorbaty