Patents by Inventor Pei-Shing E. Dai
Pei-Shing E. Dai 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: 5416054Abstract: Heavy oils may be hydrotreated in the presence of a porous alumina support bearing metals of Group VIII and VI-B and optionally phosphorus, the catalyst having a Total Surface Area of 165-230 m.sup.2 /g, a Total Pore Volume of 0.5-0.8 cc.g, and a Pore Diameter Distribution whereby less than about 5% the Total Pore Volume is present as primary micropores of diameter less than 80 .ANG., and secondary micropores of diameter of +20 .ANG. of a Pore Mode of 100-135 .ANG. are present in amount of at least about 65% of the micropore volume having pores with diameter less than 250 .ANG., and 22-29% of the Total Pore Volume is present as macropores of diameter >250 .ANG..The process of the instant invention is particularly effective in achieving desired levels of hydrodemetallation, hydrodesulfurization, and hydrocracking of asphaltenes in the fraction of hydrotreated/hydrocracked petroleum resid product having a boiling point greater than 1000.degree. F.Type: GrantFiled: February 25, 1993Date of Patent: May 16, 1995Assignee: Texaco Inc.Inventors: Pei-Shing E. Dai, Gerald V. Nelson, Govanon Nongbri, Roy E. Pratt, David E. Sherwood, Jr.
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Patent number: 5399259Abstract: Heavy oils may be hydrotreated in the presence of a porous alumina support bearing metals of Group VIII and VI-B and optionally phosphorus, the catalyst having a Total Surface Area of 165-230 m.sup.2 /g, a Total Pore Volume of 0.5-0.8 cc.g, and a Pore Diameter Distribution whereby less than about 5% of the Total Pore Volume is present as primary micropores of diameter less than 80.ANG., and secondary micropores of diameter of .+-.20.ANG. of a Pore Mode of 100-135.ANG. are present in amount of at least about 65% of the micropore volume having pores with diameter less than 250.ANG., and 22-29% of the Total Pore Volume is present as macropores of diameter >250.ANG.. The process of the instant invention is particularly effective in achieving desired levels of hydrodemetallation, hydrodesulfurization, and hydrocracking of asphaltenes in the fraction of hydrotreated/hydrocracked petroleum resid product having a boiling point greater than 1000.degree. F.Type: GrantFiled: April 20, 1992Date of Patent: March 21, 1995Assignee: Texaco Inc.Inventors: Pei-Shing E. Dai, Gerald V. Nelson, Govanon Nongbri, Roy E. Pratt, David E. Sherwood, Jr.
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Patent number: 5397456Abstract: Heavy oils may be hydrotreated in the presence of a porous alumina support bearing metals of Group VIII and VI-B and optionally phosphorus, the catalyst having a Total Surface Area of 240-310 m.sup.2 /g, a Total Pore Volume of 0.5-0.75 cc/g, and a Pore Diameter Distribution whereby 63-78% of the Total Pore Volume is present as micropores of diameter 55-115A and 11-18% of the Total Pore Volume is present as macropores of diameter greater than 250A. The heavy oils and hydrogen are contacted with the catalyst such that the catalyst is maintained at isothermal conditions and is exposed to a uniform quality of feed. The process is particularly effective in achieving desired levels of hydroconversion of feedstock components having a boiling point greater than 1000.degree. F. to products having a boiling point less than 1000.degree. F.Type: GrantFiled: February 19, 1993Date of Patent: March 14, 1995Assignee: Texaco Inc.Inventors: Pei-Shing E. Dai, David E. Sherwood, Jr.
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Patent number: 5391286Abstract: A process for catalytic hydrodewaxing hydrocarbon feedstocks is disclosed. The catalyst comprises a surface-modified crystalline aluminosilicate zeolite, such as ZSM-5 type zeolite in a matrix or binder, such as alumina, having a specified metals content. The process is especially useful for dewaxing lubricating oil basestocks.Type: GrantFiled: November 3, 1993Date of Patent: February 21, 1995Assignee: Texaco Inc.Inventors: Pei-Shing E. Dai, Robert J. Taylor, Jr., Randall H. Petty, Joseph A. Durkin
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Patent number: 5387722Abstract: Disclosed is a process for preparing alkyl tertiary alkyl ethers in one step which comprises reacting tert-butanol and a C.sub.1 -C.sub.4 primary alcohol in the presence of a catalyst consisting essentially of a pentasil zeolite having a silica/alumina ratio of 50-150, optionally with a binder at a temperature of about 80.degree. to 200.degree. C. and atmospheric pressure to about 1000 psig, wherein when the temperature is in the operating range above 140.degree. C., the product comprises a two-phase mix of a MTBE or ETBE and isobutylene product-rich phase and a heavier aqueous primary alcohol-rich phase.Type: GrantFiled: September 23, 1993Date of Patent: February 7, 1995Assignee: Texaco Chemical Inc.Inventors: John F. Knifton, Pei-Shing E. Dai
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Patent number: 5387723Abstract: Disclosed is a method for producing alkyl tertiary alkyl ethers which comprises reacting t-butanol with an alkanol in the presence of a catalyst which exhibits extended life comprising .beta.-zeolite modified with one or more metals selected from the group consisting of Group IA and Group IIIB of the Periodic Table and continuously contacting said alkanol and t-butanol in a molar amount from about 10:1 to 1:10 over said zeolite catalyst at a temperature of about 20.degree. C. to about 250.degree. C. and a pressure of about atmospheric to about 1000 psig.Type: GrantFiled: January 12, 1994Date of Patent: February 7, 1995Assignee: Texaco Chemical Inc.Inventors: John F. Knifton, Pei-Shing E. Dai
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Patent number: 5370788Abstract: Charge waxy hydrocarbon is converted to lube oil base stock by hydrotreating in the presence of catalyst characterized by its ability to convert a waxy hydrocarbon distillate of high pour point to a hydrocarbon product of reduced pour point and high viscosity index, suitable for use as a lube oil base stock, which comprises a support containing about 2-50 w % silica and 50-98 w % alumina, bearing 2-10 w % of a non-noble Group VIII metal, as metal, metal oxide, or metal sulfide, about 8-20 w % of a Group VI-B metal, as metal, metal oxide, or metal sulfide, less than 0.5% halogen; and 0-2 w % of phosphorus, the atom ratio of Group VIII metal to Group VI-B metal being about 0.3-2:1, said catalyst being characterized by a micropore mode of about 60-130 .ANG. diameter, a Total Surface Area of about 150-300 m.sup.2 /g, a Total Pore Volume of about 0.45-0.9 cc/g and a Pore Volume of pores with pore diameter >500 .ANG. of about 0.02-0.25 cc/g.Type: GrantFiled: December 18, 1992Date of Patent: December 6, 1994Assignee: Texaco Inc.Inventors: Pei-Shing E. Dai, Joseph A. Durkin, Bobby R. Martin
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Patent number: 5364981Abstract: Disclosed is an improved process for preparing alkyl tertiary alkyl ethers, especially methyl t-butyl ether, in one step which comprises reacting tertiary butanol and methanol in the presence of a catalyst comprising .beta.-zeolite modified with one or more metals selected from Group VIII of the Periodic Table, and optionally further modified with a halogen or a Group IB metal, with an alumina binder, at a temperature of about 20.degree. C. to 250.degree. C. and atmospheric pressure to about 1000 psig, wherein when the temperature is in the operating range above about 140.degree. C., the product comprises a two-phase mix of an MTBE-isobutylene and, optionally, diisobutylene product-rich phase and a heavier aqueous ethanol-rich phase.Type: GrantFiled: November 8, 1993Date of Patent: November 15, 1994Assignee: Texaco Chemical CompanyInventors: John F. Knifton, Pei-Shing E. Dai
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Patent number: 5352835Abstract: Disclosed is a process for the amination of polyols to form primary amines which comprises reacting a polyoxyalkylene alcohol or polyol having a molecular weight of from about 230 to 5000 and ammonia in the presence of hydrogen over a catalyst consisting essentially of 10 to 35 wt % nickel, 1 to 20 wt % copper and 0.1 to 2.0 wt % optionally chromium or molybdenum promoter impregnated onto a .theta.-alumina support at a temperature of 100.degree. C. to 300.degree. C. and a pressure of 1000 psig to 3000 psig wherein the .theta.-alumina support results from calcining .gamma.-alumina or pseudo-boehmite for 2-4 hours at 900.degree.-1100.degree. C.Type: GrantFiled: February 8, 1993Date of Patent: October 4, 1994Assignee: Texaco Chemical CompanyInventors: Pei-Shing E. Dai, Terry L. Renken, Laurence D. Neff
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Patent number: 5342507Abstract: A mild hydrocracking process for the hydrodemetallation (HDM), hydrodesulfurization (HDS) and hydroconversion (HC) of hydrocarbon feedstocks such as residuum feedstocks which provides increased conversion of heavy hydrocarbons boiling above 1000.degree. F. into products boiling below 1000.degree. F. as well as increased yields of middle distillates is disclosed. The process utilizes a catalyst comprising about 1.0 to about 6.0 wt. % of an oxide of a Group VIII metal, about 12.0 to about 25.0 wt. % of an oxide of molybdenum and 0 to about 5.0 wt. % of an oxide of phosphorus supported on a porous support comprising precipitated alumina or silica-containing alumina and dealuminated Y-zeolite.Type: GrantFiled: April 16, 1993Date of Patent: August 30, 1994Assignee: Texaco Inc.Inventors: Pei-Shing E. Dai, Charles N. Campbell, II, Bobby R. Martin, David E. Sherwood, Jr.
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Patent number: 5340466Abstract: Hydrodesulfurization of a cracked naphtha is effected in the presence of, as catalyst, an alkali metal, a metal of Group VIII, and a metal of Group VI-B on an alumina support containing a hydrotalcite-like composition.Type: GrantFiled: April 19, 1993Date of Patent: August 23, 1994Assignee: Texaco Inc.Inventors: Pei-Shing E. Dai, David E. Sherwood, Jr., Randall Hughes Petty
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Patent number: 5332490Abstract: A process for hydrodewaxing a hydrocarbon feedstock boiling above about 350.degree. F. by contacting the feedstock and hydrogen at a hydrogen pressure of from about 300 to about 2000 psig at a temperature of 400.degree. to 900.degree. F. and at a space velocity of about 0.1 to about 10.0 LHSV with a catalyst comprising about 0.1 to about 23 wt. % of an oxide of a Group VIII metal, such as nickel, or an oxide of a Group VIB metal, such as molybdenum; supported on a porous alumina support containing about 50 to about 85 wt. % of a crystalline alumino-silicate zeolite of the ZSM-5 type based on the weight of the support. The catalyst is further characterized by having greater than 60% of the pore volume between 45-600 Angstroms in the 70-200 Angstrom range. The process is especially useful for dewaxing lubricating oil basestocks.Type: GrantFiled: September 28, 1992Date of Patent: July 26, 1994Assignee: Texaco Inc.Inventors: Robert J. Taylor, Jr., Pei-Shing E. Dai, Randall H. Petty, Joseph A. Durkin
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Patent number: 5322616Abstract: A mild hydrocracking process for the hydrodemetallation (HDM), hydrodesulfurization (HDS) and hydroconversion (HC) of hydrocarbon feedstocks such as residuum feedstocks which provides increased conversion and increased yields of middle distillates is disclosed. The process utilizes a catalyst comprising about 1.0 to about 6.0 wt. % of an oxide of a Group VIII metal, about 12.0 to about 25.0 wt. % of an oxide of molybdenum and about 0 to about 5.0 wt. % of an oxide of phosphorus supported on a porous alumina support containing about 0.1 to about 10.0 wt. % of lithium oxide.Type: GrantFiled: March 30, 1992Date of Patent: June 21, 1994Assignee: Texaco Inc.Inventors: Pei-Shing E. Dai, Charles N. Campbell, II, Joseph A. Durkin, David E. Sherwood, Jr.
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Patent number: 5320743Abstract: A mild hydrocracking process for the hydrodemetallation (HDM), hydrodesulfurization (HDS) and hydroconversion (HC) of hydrocarbon feedstocks such as residuum feedstocks which provides increased conversion of the 1000.degree. F.+ hydrocarbon fraction to the 1000.degree. F.- fraction and increased yields of middle distillates is disclosed. The process utilizes a catalyst comprising about 2.0 to about 6.0 wt. % of an oxide of a Group VIII metal, about 12.0 to about 25.0 wt. % of an oxide of molybdenum and 0 to about 3.0 wt. % of an oxide of phosphorus supported on a porous alumina support containing about 4.0 to about 30 wt. % of silica.Type: GrantFiled: May 29, 1992Date of Patent: June 14, 1994Assignee: Texaco Inc.Inventors: Pei-Shing E. Dai, Charles N. Campbell II, Bobby R. Martin, Randall H. Petty
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Patent number: 5308472Abstract: A mild hydrocracking process for the hydrodemetallation (HDM), hydrodesulfurization (HDS) and hydroconversion (HC) of hydrocarbon feedstocks such as residuum feedstocks which provides increased conversion of heavy hydrocarbons boiling above 1000.degree. F. into products boiling below 1000.degree. F. as well as increased yields of middle distillates is disclosed. The process utilizes a catalyst comprising about 1.0 to about 6.0 wt. % of an oxide of a Group VIII metal, about 12.0 to about 25.0 wt. % of an oxide of molybdenum and 0.1 to about 5.0 wt. % of an oxide of phosphorus supported on a porous support comprising precipitated alumina or silica-containing alumina and hydrogen form, acidified, dealuminated Y-zeolite.Type: GrantFiled: June 11, 1992Date of Patent: May 3, 1994Assignee: Texaco Inc.Inventors: Pei-Shing E. Dai, Charles N. Campbell, II, Bobby R. Martin, David E. Sherwood, Jr.
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Patent number: 5256828Abstract: Disclosed is a process for producing narrow range glycols which comprises reacting a glycol with ethylene oxide in the presence of a heterogeneous catalyst consisting essentially of an alkali metal, alkaline earth metal or alkali metal halide impregnated into an inorganic solid oxide selected from the groups consisting of small pore faujasite zeolites, pentasil zeolites, small pore ferrierite zeolites, two-dimensional mordenite zeolites, .beta.-type zeolite, basic zeolites and Group IV oxides or mixtures thereof.Type: GrantFiled: February 25, 1993Date of Patent: October 26, 1993Assignee: Texaco Chemical CompanyInventors: Michael Cuscurida, John F. Knifton, Pei-Shing E. Dai
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Patent number: 5143878Abstract: A hydrocarbon conversion process to yield product of improved properties is effected in the presence of a zeolite characterized by increased Secondary Pore Volume, decreased Lattice Constant, Secondary Pore Mode, Secondary Pore Diameter, increased Secondary Pore Volume, Surface Silicon to Aluminum Atom Ratio, and Acid Site Density.Type: GrantFiled: August 2, 1991Date of Patent: September 1, 1992Assignee: Texaco Inc.Inventors: Pei-Shing E. Dai, David E. Sherwood, Jr.
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Patent number: 5126299Abstract: Sulfur oxides are removed from gases by contact with a composition containing 3 wt % potassium and 1 wt % thorium on alumina.Type: GrantFiled: January 22, 1990Date of Patent: June 30, 1992Assignee: Texaco Inc.Inventors: Pei-Shing E. Dai, Edward H. Holst
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Patent number: 5112473Abstract: A hydrocarbon conversion process to yield product of improved properties is effected in the presence of a zeolite characterized by increased Secondary Pore Volume, decreased Lattice Constant, Secondary Pore Mode, Secondary Pore Diameter, increased Secondary Pore Volume, Surface Silicon to Aluminum Atom Ratio, and Acid Site Density.Type: GrantFiled: June 4, 1990Date of Patent: May 12, 1992Assignee: Texaco Inc.Inventors: Pei-Shing E. Dai, David E. Sherwood, Jr.
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Patent number: 5094994Abstract: A catalyst composition useful in the hydroprocessing of a sulfur- and metal-containing hydrocarbon feedstock comprises 1.0-5.0 weight percent of an oxide of nickel or cobalt and 10.0-25.0 weight percent of an oxide of molybdenum, all supported on a porous alumina support in such a manner that the molybdenum gradient of the catalyst has a value of less than 6.0 and 15-30% of the nickel or cobalt contained in the catalyst is in an acid extractable form. The catalyst is further characterized by having a total surface area of 150-210 m.sup.2 /g, a total pore volume of 0.50-0.75 cc/g, and a pore size distribution such that pores having diameters of less than 100A constitute less than 25.0%, pores having diameters of 100-160A constitute 70.0-85.0% and pores having diameters of greater than 250A constitute 1.0-15.0% of the total pore volume of the catalyst.Type: GrantFiled: January 25, 1991Date of Patent: March 10, 1992Assignee: Texaco Inc.Inventors: David E. Sherwood, Jr., Burton H. Bartley, Laurence D. Neff, Pei-Shing E. Dai