Patents by Inventor Yung F. Chu

Yung F. Chu 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).

  • Patent number: 5157185
    Abstract: Alkylation of aromatics, e.g. ethylbenzene preparation, with minimized o-xylene make by contacting with olefin alkylating agent in the presence of ZSM-5 crystals having a diffusion rate constant of at least about 100 sec.sup.-1 .times.10.sup.-6 and an alpha value of less than about 100 prepared from a non-organic forming mixture comprising a silica source of precipitated silica having a particle size of 1 to 500 microns.
    Type: Grant
    Filed: September 1, 1989
    Date of Patent: October 20, 1992
    Assignee: Mobil Oil Corporation
    Inventors: Yung F. Chu, David O. Marler, John P. McWilliams
  • Patent number: 4927525
    Abstract: An improved zeolite catalyst containing at least one noble metal and at least one alkali metal wherein the amount of the latter component exceeds the cationic exchange capacity of the zeolite has been found to be highly useful for catalytic reforming.
    Type: Grant
    Filed: August 30, 1988
    Date of Patent: May 22, 1990
    Assignee: Mobil Oil Corporation
    Inventor: Yung F. Chu
  • Patent number: 4927521
    Abstract: An improved process for pretreating a naphtha comprising contacting said naphtha prior to reforming with a zeolite catalyst containing at least one noble metal and at least one alkali metal.
    Type: Grant
    Filed: August 30, 1988
    Date of Patent: May 22, 1990
    Assignee: Mobil Oil Corporation
    Inventor: Yung F. Chu
  • Patent number: 4916097
    Abstract: A method for activation of an organic cation-containing crystalline catalyst is disclosed. The method includes contacting the catalyst with steam under conditions to decompose the organic cations, which result in the activation of the catalyst. The method has the advantage that organic cations are converted to non-hazardous by-products such as ammonia and light hydrocarbons such as ethylene. These are more easily controlled by environmental control schemes than higher molecular weight by-products resulting from traditional activation methods (nitrogen or nitrogen/air). The steamed catalyst can optionally be calcined to remove any organic material which may remain after steaming.For instance, a major product which results from decomposting the tetraethylammonium organic cations in zeolite .beta. is ethylene. The ethylene can be subsequently converted into carbon dioxide and water by oxidation.
    Type: Grant
    Filed: May 16, 1988
    Date of Patent: April 10, 1990
    Assignee: Mobil Oil Corp.
    Inventors: Yung F. Chu, John P. McWilliams
  • Patent number: 4899011
    Abstract: A new xylene isomerization process which is capable of converting ethylbenzene and non-aromatic exhaustively while selectively converting xylenes to thermal equilibrium in mixed EB/xylene feeds is proposed. The new process employs a two component catalyst system; each of the components contains a strong hydrogenation metal and a zeolite. The zeolite of each of the two components differs from the other in its selectivity for xylene isomerization and its capacity to deethylete ethylbenzene. That selectivity for xylene isomerization is described by xylene diffusion properties of the zeolite.
    Type: Grant
    Filed: January 15, 1986
    Date of Patent: February 6, 1990
    Assignee: Mobil Oil Corporation
    Inventors: Yung F. Chu, Charles T. Kresge, Rene B. LaPierre
  • Patent number: 4885426
    Abstract: A process is provided for transalkylation of polyalkylaromatics over a catalyst comprising a molecular sieve having a high lattice aluminum content whereby its silica/alumina mole ratio is less than 40 and an alpha value of at least about 140.
    Type: Grant
    Filed: March 23, 1989
    Date of Patent: December 5, 1989
    Assignee: Mobil Oil Corporation
    Inventors: Yung F. Chu, David O. Marler, John P. McWilliams
  • Patent number: 4847055
    Abstract: A process for producing zeolite beta is described by employing in the reaction mixture a source of silicon which has a particle size of 1 to 500, and controlling the purity of the product by controlling the amount of tetraethylammonium cation in the reaction mixture.
    Type: Grant
    Filed: November 24, 1987
    Date of Patent: July 11, 1989
    Assignee: Mobil Oil Corporation
    Inventor: Yung F. Chu
  • Patent number: 4822941
    Abstract: A process is provided for producing aromatic compounds which comprises contacting under conversion conditions a feed comprising aliphatic hydrocarbons, with a crystalline aluminosilicate zeolite catalyst in its acid form having a Constraint Index in the range of about 1 to 12 and prepared by crystallizing a composition comprising an aqueous suspension of a precipitated amorphous silica or aluminosilicate precursor composed of a preponderant number of particles having a particle size in the range of about 1 to 500 microns, said composition being free of any organic or inorganic directing agent and containing a dissolved alumina source if a precipitated amorphous silica is utilized or a precipitated amorphous aluminosilicate is utilized containing less than the desired amount of aluminum. The catalyst is advantageously subjected to a thermal or steam treatment, and/or is impregnated with gallium before being used in the conversion.
    Type: Grant
    Filed: July 25, 1988
    Date of Patent: April 18, 1989
    Assignee: Mobil Oil Corporation
    Inventors: David J. Baillargeon, Yung F. Chu
  • Patent number: 4696732
    Abstract: A process for simultaneously hydrotreating and dewaxing petroleum fractions is described. The process utilizes a single catalyst system which includes a hydrotreating component impregnated on a controlled pore size base and at least two catalyst components selected from any of an intermediate pore zeolite, a large pore zeolite or Zeolite Beta, and a large pore non-zeolite catalyst.
    Type: Grant
    Filed: February 14, 1986
    Date of Patent: September 29, 1987
    Assignee: Mobil Oil Corporation
    Inventors: Philip J. Angevine, Yung F. Chu, Kenneth M. Mitchell, Stephen M. Oleck, Stuart S. Shih, Robert C. Wilson, Jr., deceased
  • Patent number: 4663492
    Abstract: A feedstock of low molecular weight oxygenates such as methanol and/or dimethylether is contacted with a mildly presteamed or hydro-thermally treated zeolite catalyst in a reaction zone to produce liquid hydrocarbons in the gasoline boiling range. The pretreated zeolite catalyst has an .alpha.-value (acid cracking activity) substantially the same as the .alpha.-value of fresh unsteamed catalyst and shows increased stability and resistance to aging under oxygenate conversion conditions of elevated temperature and pressure.
    Type: Grant
    Filed: June 9, 1986
    Date of Patent: May 5, 1987
    Assignee: Mobil Oil Corporation
    Inventors: Arthur W. Chester, Yung F. Chu
  • Patent number: 4595702
    Abstract: This invention provides a process for converting synthesis gas to hydrocarbon fuels in the C.sub.5 -C.sub.24 (gasoline and distillate) range. The conversion proceeds with minimal formation of by-product fractions. The conversion is accomplished with a low nitrogen content iron catalyst intimately mixed with a selected zeolite.
    Type: Grant
    Filed: April 3, 1985
    Date of Patent: June 17, 1986
    Assignee: Mobil Oil Corporation
    Inventors: Yung F. Chu, James A. Brennan, Arthur W. Chester
  • Patent number: 4592828
    Abstract: Petroleum resid is upgraded in an improved process to produce a low pour point 650.degree.-775.degree. F. fraction without disturbing the product characteristics of other distillate boiling range fractions. The 650.degree.-775.degree. F. fraction is dewaxed separately from the remaining hydrodesulfurized product.
    Type: Grant
    Filed: May 7, 1984
    Date of Patent: June 3, 1986
    Assignee: Mobil Oil Corporation
    Inventors: Yung F. Chu, Stuart S. Shih
  • Patent number: 4522929
    Abstract: A zeolite of improved stability for use in acid-catalyzed reactions is prepared by mildly presteaming the catalyst under controlled conditions of temperature, time, and steam partial pressure. The resulting catalyst retains nearly the same activity as that of a fresh unsteamed catalyst.
    Type: Grant
    Filed: October 6, 1983
    Date of Patent: June 11, 1985
    Assignee: Mobil Oil Corporation
    Inventors: Arthur W. Chester, Yung F. Chu
  • Patent number: 4490569
    Abstract: The elution of zinc from zinc-impregnated zeolite catalysts is minimized by incorporating gallium into the catalyst composition. Optionally, palladium may also be included in the composition. The catalyst composition is used to effect the conversion of propane in hydrocarbon streams to aromatic hydrocarbons.
    Type: Grant
    Filed: December 2, 1983
    Date of Patent: December 25, 1984
    Assignee: Mobil Oil Corporation
    Inventors: Yung F. Chu, Arthur W. Chester
  • Patent number: 4482773
    Abstract: Isomerization of xylene in admixture with ethylbenzene by contact with a zeolite catalyst such as ZSM-5 is improved by use of a zeolite having a catalyst particle size of at least 1 micron and having incorporated thereon two metals such as platinum and magnesium.
    Type: Grant
    Filed: July 22, 1983
    Date of Patent: November 13, 1984
    Assignee: Mobil Oil Corporation
    Inventors: Yung F. Chu, Fritz A. Smith, Arthur W. Chester
  • Patent number: 4429176
    Abstract: A zeolite of improved stability for use in acid-catalyzed reactions is prepared by mildly presteaming the catalyst under controlled conditions of temperature, time, and steam partial pressure. The resulting catalyst retains nearly the same activity as that of a fresh unsteamed catalyst.
    Type: Grant
    Filed: February 8, 1982
    Date of Patent: January 31, 1984
    Assignee: Mobil Oil Corporation
    Inventors: Arthur W. Chester, Yung F. Chu
  • Patent number: 4392989
    Abstract: The elution of zinc from zinc-impregnated zeolite catalysts is minimized by incorporating gallium into the catalyst composition. Optionally, palladium may also be included in the composition. The catalyst composition is used to effect the conversion of propane in hydrocarbon streams to aromatic hydrocarbons.
    Type: Grant
    Filed: May 11, 1981
    Date of Patent: July 12, 1983
    Assignee: Mobil Oil Corporation
    Inventors: Yung F. Chu, Arthur W. Chester
  • Patent number: 4387261
    Abstract: A process is disclosed for the dealkylation of durene resulting from a methanol to gasoline conversion by contacting a durene-containing fraction with zeolite ZSM-12 at elevated temperatures and pressures.
    Type: Grant
    Filed: April 9, 1982
    Date of Patent: June 7, 1983
    Assignee: Mobil Oil Corporation
    Inventors: Arthur W. Chester, Yung F. Chu
  • Patent number: 4351979
    Abstract: Isomerization of xylene admixed with other alkyl aromatics of at least eight carbon atoms and with normal or slightly branched paraffins is conducted at 600.degree.-800.degree. F. with a zeolite like zeolite ZSM-5 of reduced acid activity.
    Type: Grant
    Filed: April 24, 1981
    Date of Patent: September 28, 1982
    Assignee: Mobil Oil Corporation
    Inventors: Arthur W. Chester, Yung F. Chu
  • Patent number: 4350835
    Abstract: A catalytic process is provided for converting gaseous feedstocks containing ethane to liquid aromatics by contacting said gaseous feeds in the absence of added air or oxygen, under conversion conditions, with a crystalline zeolite catalyst having incorporated therein a minor amount of gallium, thereby converting the ethane in the feedstock to aromatics and recovering a liquid mixture of benzene, toluene and xylene.
    Type: Grant
    Filed: February 19, 1981
    Date of Patent: September 21, 1982
    Assignee: Mobil Oil Corporation
    Inventors: Arthur W. Chester, Yung F. Chu