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: 5637778Abstract: Disclosed is a one-step method for synthesis of methyl tertiary butyl ether, diisopropyl ether and isopropyl ether from crude streams containing acetone, methanol and t-butyl alcohol which comprises reacting an acetone-rich feed over a bifunctional catalyst comprising 5-45% by weight of a catalyst consisting essentially of a hydrogenation catalyst selected from the group consisting of one or more metals selected from the group consisting of IB, VIB or VIII of the Periodic Table and a heteropoly acid on a 55%-95% of the total weight of the catalyst of a support comprising a compound selected from the group consisting of:a. a metal phosphate;b. 5 to 95% by weight metal phosphate supported on 95 to 5 wt % Group III or IV oxide; andc. a large pore silicoaluminophosphate.Type: GrantFiled: August 8, 1994Date of Patent: June 10, 1997Assignee: Texaco Chemical Inc.Inventors: Robert J. Taylor, Jr., Pei-Shing E. Dai, John F. Knifton, Bobby R. Martin
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Patent number: 5616530Abstract: Disclosed is a catalyst comprising a porous alumina support bearing 2.5-6 wt % of a non-cobalt Group VIII metal oxide, 14.5-25 wt % of a Group VI-B metal oxide, and 0-4 wt % of a phosphorus oxide, said catalyst having a Total Surface Area of 240-320 M.sup.2 /g, Pore Volume of 0.65-0.90 cc/g, and a Pore Diameter Distribution whereby 50-62.8% of the Total Pore Volume is present as micropores of diameter 55-115 .ANG., 27.5-37% of the Total Pore Volume is present in large pores of a diameter greater than 160 .ANG. and 20-30.5% of the Total Pore Volume is present as macropores of diameter greater than 250 .ANG..Type: GrantFiled: November 29, 1995Date of Patent: April 1, 1997Assignee: Texaco Inc.Inventors: David E. Sherwood, Jr., Pei-Shing E. Dai, Charles N. Campbell, II
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Patent number: 5583266Abstract: A two-step integrated process for the generation of diisopropyl ether from a crude by-product acetone stream which comprises:a) Hydrogenating said crude acetone over a supported, hydrogenation catalyst to give an isopropanol-rich effluent;b) passing said isopropanol-rich intermediate directly to a second reactor, andc) subject said IPA to dehydration conditions in the presence of hydrogen and a strong acid zeolite catalyst from the group consisting of .beta.-zeolite, optionally modified with one or more metals from Groups IB, VIB, VIIB and VIII of the Periodic Table, and a dealuminized Y-zeolite.Type: GrantFiled: May 2, 1994Date of Patent: December 10, 1996Assignee: Texaco Inc.Inventors: Robert J. Taylor, Jr., Pei-Shing E. Dai, John F. Knifton
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Patent number: 5550300Abstract: Disclosed is an integrated process for the generation of a mixture of ethers, such as diisopropyl ether, methyl tertiary butyl ether, and/or isopropyl tertiary butyl ether, from a crude by-product acetone stream composed of acetone, tertiary butyl alcohol and methanol by passing such a stream, in the presence of hydrogen, over a catalyst system characterized by having both a hydrogenation activity gradient along the reactor in one direction and an etherification activity gradient in the opposite direction.Type: GrantFiled: December 30, 1994Date of Patent: August 27, 1996Assignee: Texaco Chemical Inc.Inventors: Robert J. Taylor, Jr., Pei-Shing E. Dai, John F. Knifton
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Patent number: 5549813Abstract: Disclosed is a fluid catalytic cracking process for cracking gas oils and naphtha which provides improved selectivity for C.sub.3 -C.sub.5 olefins employing a catalyst comprising a novel zeolite characterized by a large number of secondary pores, a substantially decreased Lattice Constant of below about 24.19 .ANG., and a substantially decreased Acid Site Density, attained by hydrothermal and acid-treating of an ultrastable Y-zeolite.Type: GrantFiled: March 7, 1994Date of Patent: August 27, 1996Inventors: Pei-Shing E. Dai, Chih-Hao M. Tsang, Laurence D. Neff, Randall H. Petty
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Patent number: 5545602Abstract: Heavy hydrocarbons are hydrotreated to increase content of components boiling below 1000.degree. F. by contact with Group VIII non-noble metal oxide and Group VI-B metal oxide on alumina having a Total Surface Area of 150-240 m.sup.2 /g, a Total Pore Volume, (TPV) of 0.7-0.98, and a Pore Diameter Distribution whereby .ltoreq.20% of the TPV is present as primary micropores of diameter .ltoreq.100 .ANG., at least about 34% of TPV is present as secondary micropores of diameter of about 100 .ANG.-200 .ANG., and about 26%-46% of the TPV is present as mesopores of diameter .gtoreq.200 .ANG..Type: GrantFiled: April 20, 1995Date of Patent: August 13, 1996Assignee: Texaco Inc.Inventors: Gerald V. Nelson, Govanon Nongbri, Roy E. Pratt, David E. Sherwood, Jr., Pei-Shing E. Dai
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Patent number: 5534135Abstract: A novel zeolite characterized by a large number of secondary pores, a substantially decreased Lattice Constant of below about 24.19 .ANG., and a substantially decreased Acid Site Density is attained by hydrothermal and acid-treating of an ultrastable Y-zeolite.Type: GrantFiled: March 7, 1994Date of Patent: July 9, 1996Assignee: ABB Lummus Global Inc.Inventors: Pei-Shing E. Dai, David E. Sherwood, Jr., Burton H. Bartley
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Patent number: 5514273Abstract: Heavy oils may be hydrotreated in the presence of a porous alumina support bearing metals of Group VIII, excluding cobalt, and VI-B and optionally phosphorus, the catalyst having a Total Surface Area of 240-320 m.sup.2 /g, a Total Pore Volume of 0.65-0.9 cc/g, and a Pore Diameter Distribution whereby 50-62.8% of the Total Pore Volume is present as micropores of diameter 55-115 .ANG. and 20-30.5% of the Total Pore Volume is present as macropores of diameter greater than 250 .ANG..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: October 1, 1993Date of Patent: May 7, 1996Assignee: Texaco Inc.Inventors: David E. Sherwood, Jr., Pei-Shing E. Dai, Charles N. Campbell, II
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Patent number: 5498586Abstract: Disclosed is a hydrotreating catalyst which comprises 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 55-115 .ANG. and 11-18% of the Total Pore Volume is present as macropores of diameter greater than 250 .ANG., said catalyst being 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: November 3, 1994Date of Patent: March 12, 1996Assignee: Texaco Inc.Inventors: Pei-Shing E. Dai, David E. Sherwood, Jr.
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Patent number: 5488178Abstract: Disclosed is a method of selective preparation of ditertiary butyl peroxide from tertiary butyl hydroperoxide and t-butanol which comprises reacting said tertiary butyl hydroperoxide and t-butanol over a solid acid catalyst selected from:a) an acidic montmorillonite clay;b) an acidic zeolite selected from the group consisting of dealuminized Y-zeolite and pentasil zeolite;c) an acidic organic resin; andd) heteropoly acids supported on an oxide selected from Group III or Group IV.Type: GrantFiled: March 8, 1995Date of Patent: January 30, 1996Assignee: Texaco Chemical Inc.Inventors: John F. Knifton, Edward T. Marquis, Pei-Shing E. Dai
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Patent number: 5488179Abstract: Disclosed is a method of selective preparation of ditertiary butyl peroxide from tertiary butyl hydroperoxide and t-butanol which comprises reacting said tertiary butyl hydroperoxide and t-butanol over a Beta-zeolite catalyst under hydroperoxide conversion conditions.Type: GrantFiled: March 8, 1995Date of Patent: January 30, 1996Assignee: Texaco Chemical Inc.Inventors: John F. Knifton, Edward T. Marquis, Pei-Shing E. Dai
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Patent number: 5476972Abstract: Disclosed is a one-step method for synthesis of ethers from mixtures of acetone and t-butyl alcohol which comprises reacting an acetone-rich feed over a bifunctional catalyst comprising 5%-45% by weight hydrogenation catalyst on 55%-95% of the total catalyst weight of a support comprising a zeolite and a Group III or IV oxide.Type: GrantFiled: January 28, 1994Date of Patent: December 19, 1995Assignee: Texaco Chemical Inc.Inventors: Pei-Shing E. Dai, Robert J. Taylor, Jr., John F. Knifton, Bobby R. Martin
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Patent number: 5472594Abstract: Disclosed is a process for converting a hydrocarbon charge to a product containing improved yields of C.sub.4 /C.sub.5 olefins with a reduction in the loss of gasoline yield which comprises:passing said hydrocarbon charge into contact with a catalyst comprising a phosphorus-containing medium pore zeolite mixed as an additive with Y-zeolite in a weight ratio of 0.005 to 0.10, said zeolites in separate or composite spray dried particles,wherein the catalyst to oil ratio is 0.1 to 10, reacting said hydrocarbon charge at a temperature of 800.degree. F. to 1200.degree. F., a pressure of 0 to 150 psig, and in the absence of added hydrogen, thereby producing a product containing improved yields of C.sub.4 /.sub.5 olefins and reduced loss in gasoline yield.Type: GrantFiled: July 18, 1994Date of Patent: December 5, 1995Assignee: Texaco Inc.Inventors: Chih-Hao M. Tsang, Laurence D. Neff, Pei-Shing E. Dai
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Patent number: 5459118Abstract: 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: May 9, 1994Date of Patent: October 17, 1995Assignee: Texaco Inc.Inventors: Pei-Shing E. Dai, David E. Sherwood, Jr., Randall H. Petty
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Patent number: 5453411Abstract: 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: February 22, 1994Date of Patent: September 26, 1995Assignee: Texaco Inc.Inventors: Pei-Shing E. Dai, Charles N. Campbell, II, Bobby R. Martin, Randall H. Petty
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Patent number: 5449838Abstract: Disclosed is a two-step process for the generation of isopropyl t-butyl ether from a crude by-product acetone stream which comprises:a) Hydrogenating said crude acetone over a bulk metal, nickel-rich catalyst to give an isopropanol-rich effluent;b) subjecting said isopropanol-rich intermediate to etherification conditions in the presence of a strong acid catalyst selected from:(1) a cationic resin;(2) a .beta.-zeolite;(3) dealuminized Y-zeolites; and(4) metal-modified .beta.-zeolites.Type: GrantFiled: December 30, 1993Date of Patent: September 12, 1995Assignee: Texaco Chemical Inc.Inventors: John F. Knifton, Ernest L. Yeakey, Pei-Shing E. Dai
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Patent number: 5449839Abstract: Disclosed is an improved process for preparing ethyl t-butyl ether in one step which comprises reacting tertiary butanol and ethanol in the presence of a catalyst selected from zeolite beta and zeolite beta modified with multimetals selected from the group consisting of Groups IB, VB, VIB, VIIB or VIII of the Periodic Table 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 ETBE-isobutylene and, optionally, diisobutylene product-rich phase and a heavier aqueous ethanol-rich phase.Type: GrantFiled: July 22, 1994Date of Patent: September 12, 1995Assignee: Texaco Chemical Inc.Inventors: John F. Knifton, Pei-Shing E. Dai
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Patent number: 5436215Abstract: 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 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: December 6, 1993Date of Patent: July 25, 1995Assignee: Texaco Inc.Inventors: Pei-Shing E. Dai, Charles N. Campbell, II, Joseph A. Durkin, David E. Sherwood, Jr.
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Patent number: 5435908Abstract: Heavy hydrocarbons are hydrotreated to increase content of components boiling below 1000.degree. F. by contact with Group VIII non-noble metal oxide and Group VI-B metal oxide on alumina having a Total Surface Area of 150-240 m.sup.2 /g, a Total Pore Volume, (TPV) of 0.7-0.98, and a Pore Diameter Distribution whereby .ltoreq.20% of the TPV is present as primary micropores of diameter .ltoreq.100 .ANG., at least about 34% of TPV is present as secondary micropores of diameter of about 100 .ANG.-200 .ANG., and about 26%-46% of the TPV is present as mesopores of diameter >200 .ANG..Type: GrantFiled: May 16, 1994Date of Patent: July 25, 1995Assignee: Texaco Inc.Inventors: Gerald V. Nelson, Govanon Nongbri, Roy E. Pratt, David E. Sherwood, Jr., Pei-Shing E. Dai
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Patent number: 5430198Abstract: Disclosed is a two-step process for the generation of diisopropyl ether from a crude by-product acetone stream which comprises:a) Hydrogenating said crude acetone over a bulk-metal, nickel-rich catalyst to give an isopropanol-rich effluent;b) Dehydrating said isopropanol-rich intermediate in the presence of a strong acid zeolite catalyst from the group consisting of .beta.-zeolite, optionally modified with one or more metals from Group IB, VB, VIB, VIIB and VIII of the Periodic Table, and a dealuminized Y-zeolite, wherein the dehydration temperature is from about 80.degree. C. to 200.degree. C.Type: GrantFiled: November 8, 1993Date of Patent: July 4, 1995Assignee: Texaco Chemical Inc.Inventors: John F. Knifton, Pei-Shing E. Dai