Patents by Inventor Stephen M. Davis

Stephen M. Davis 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: 5356845
    Abstract: A process for the reactivation, or rejuvenation of a nickel-alumina catalyst employed in the production of a gas comprised of an admixture of hydrogen and carbon monoxide, or synthesis gas, by the conversion, in a reactor, or reaction zone, of light hydrocarbons in a fluidized bed of the catalyst at elevated temperature, in the presence of steam and oxygen. Catalyst reactivation is accomplished by withdrawing a portion of the catalyst from the fluidized bed of the reactor and treating the catalyst in an oxidation zone at temperature sufficient to oxidize and convert the nickel component of the catalyst to nickel aluminate and disperse said nickel aluminate within the alumina support, and then recycling the treated catalyst to the reactor, or reaction zone, to reactivate and increase the activity of the catalyst.
    Type: Grant
    Filed: May 11, 1993
    Date of Patent: October 18, 1994
    Assignee: Exxon Research and Engineering Company
    Inventors: LeRoy R. Clavenna, Stephen M. Davis, Brent E. Beasley
  • Patent number: 5348717
    Abstract: A process utilizing a particulate catalyst, or particulate catalyst admixed with particulate heat transfer solids for conducting high temperature fluidized bed syn gas operations. Hydrogen and carbon monoxide are produced from a low molecular weight hydrocarbon by contact thereof, at high temperature in the presence of oxygen, or steam and oxygen, with a fluidized bed comprising said particulate solids. In one of its forms, barium hexaluminate is employed as a heat transfer solid, in concentrations ranging generally from about 10 wt. % to about 99.9 wt. %, in admixture with a particulate catalyst containing a metal, or metals, component catalytic for the production of hydrogen and carbon monoxide from low molecular weight hydrocarbons contacted with a fluidized bed of the catalyst at high temperature hydrothermal conditions. The catalyst, suitably one having a barium hexaluminate carrier component, is employed in concentration ranging generally from about 0.1 wt. % to about 90 wt. %.
    Type: Grant
    Filed: May 11, 1993
    Date of Patent: September 20, 1994
    Assignee: Exxon Research & Engineering Co.
    Inventors: LeRoy R. Clavenna, Stephen M. Davis, Geoffrey R. Say, Rocco A. Fiato
  • Patent number: 5338441
    Abstract: The present invention relates to a catalytic process for converting a solid carbonaceous material, such as coal, to a liquid product in the presence of hydrogen. More particularly, this invention relates to a coal liquefaction process wherein a mixture of coal, bottoms, solvent and a sulfiding agent is subjected to liquefaction conditions in the presence of a catalyst precursor. This catalyst or catalyst precursor is comprised of a thermally decomposable compound of Groups IIB, IVB, VB, VIB, VIIB, and VIII of the Periodic Table of the Elements such as molybdenum.
    Type: Grant
    Filed: October 13, 1992
    Date of Patent: August 16, 1994
    Assignee: Exxon Research and Engineering Company
    Inventors: Steve C. LeViness, Steve J. Hsia, Michael Y. Wen, Stephen M. Davis, Claude C. Culross, Peter S. Maa
  • Patent number: 5322619
    Abstract: A fluid catalytic cracking process for producing relatively low emissions fuels. The feedstock is relatively low in nitrogen and aromatics and high in hydrogen content and the catalyst is a rare-earth promoted amorphous silica-alumina catalyst. The feedstock can be characterized as having less than about 50 wppm nitrogen; greater than about 13 wt. % hydrogen; less than about 7.5 wt. % 2+ ring aromatic cores; and not more than about 15 wt. % aromatic cores overall.
    Type: Grant
    Filed: November 30, 1992
    Date of Patent: June 21, 1994
    Assignee: Exxon Research and Engineering Company
    Inventors: Stephen M. Davis, William E. Winter, Daniel F. Ryan
  • Patent number: 5318693
    Abstract: A fluid catalytic cracking process for producing relatively low emissions fuels. The feedstock is relatively low in nitrogen and aromatics and high in hydrogen content and the catalyst is an amorphous silica-alumina containing a separate surface silica phase. The feedstock can be characterized as having less than about 50 wppm nitrogen; greater than about 13 wt. % hydrogen; less than about 7.5 wt. % 2+ ring aromatic cores; and not more than about 15 wt. % aromatic cores overall.
    Type: Grant
    Filed: November 30, 1992
    Date of Patent: June 7, 1994
    Assignee: Exxon Research and Engineering Company
    Inventors: Stephen M. Davis, William E. Winter
  • Patent number: 5292989
    Abstract: A catalyst useful for hydroisomerizing wax containing feeds comprises a Group VIII metal on an alumina or silica-alumina support having less than about 35 wt % silica and is surface treated with at least about 0.5 wt % silica or a silica precursor.
    Type: Grant
    Filed: January 8, 1993
    Date of Patent: March 8, 1994
    Assignee: Exxon Research & Engineering Co.
    Inventor: Stephen M. Davis
  • Patent number: 5258411
    Abstract: The activity of supported cobalt catalysts for hydrocarbon synthesis is maximized by carrying out the reduction at conditions that keep both the partial pressure of water vapor and the maximum reduction temperature below critical maximum values. For titania supported cobalt catalysts, the preferred maximum water partial pressure is one atmosphere and the preferred maximum reduction temperature is 375.degree. C.
    Type: Grant
    Filed: June 10, 1992
    Date of Patent: November 2, 1993
    Assignee: Exxon Research and Engineering Co.
    Inventors: William C. Behrmann, Stephen M. Davis, Charles H. Mauldin
  • Patent number: 5219816
    Abstract: A supported catalyst and a method of making a supported catalyst useful in the dehydrogenation of light paraffins. This catalyst comprises 0.3 to 5 wt. % Ga and 0.1 to 5 wt. % Pt on a spinel type support material characterized by the formula Mg.sub.x Al.sub.2 O.sub.3+x where x is a number from about 0.1 to 1.1. The improvement comprises the incorporation of a water soluble Mg salt into said support prior to the impregnation of Pt and Ga.
    Type: Grant
    Filed: December 20, 1991
    Date of Patent: June 15, 1993
    Assignee: Exxon Research & Engineering Company
    Inventors: Ying Zhou, Stephen M. Davis
  • Patent number: 5214227
    Abstract: A process for the dehydrogenation of light alkanes which employs a gallium/platinum catalyst on a magnesium/alumina spinel support. The catalyst comprises 0.3 to 5 wt. % Ga and 0.1 to 5 wt. % Pt on a spinel type support material characterized by the formula Mg.sub.x Al.sub.2 O.sub.3+x where x is a number from about 0.1 to 1.1. A water soluble Mg salt is incorporated into this support prior to the impregnation of Pt and Ga.
    Type: Grant
    Filed: December 20, 1991
    Date of Patent: May 25, 1993
    Assignee: Exxon Research & Engineering Company
    Inventors: Ying Zhou, Stephen M. Davis
  • Patent number: 5187138
    Abstract: A catalyst useful for hydroisomerizing wax containing feeds comprises a Group VIII metal on an alumina or silica-alumina support having less than about 35 wt % silica and is surface treated with at least about 0.5 wt % silica or a silica precursor.
    Type: Grant
    Filed: September 16, 1991
    Date of Patent: February 16, 1993
    Assignee: Exxon Research and Engineering Company
    Inventor: Stephen M. Davis
  • Patent number: 5168091
    Abstract: The activity of supported cobalt catalysts for hydrocarbon synthesis is maximized by carrying out the reduction at conditions that keep both the partial pressure of water vapor and the maximum reduction temperature below critical maximum values. For titania supported cobalt catalysts, the preferred maximum water partial pressure is one atmosphere and the preferred maximum reduction temperature is 375.degree. C.
    Type: Grant
    Filed: September 30, 1991
    Date of Patent: December 1, 1992
    Assignee: Exxon Research and Engineering Company
    Inventors: William C. Behrmann, Stephen M. Davis, Charles H. Mauldin
  • Patent number: 5019543
    Abstract: Crystalline aluminosilicate zeolites having increased silica to alumina mole ratios are prepared by a process wherein a conventional crystalline aluminosilicate zeolite is treated to remove alumina from the crystal lattice. By-product non-framework amorphous alumina is then selectively removed from the zeolite either by using a blocking agent, to prevent removal of framework aluminum during a subsequent acid treatment, or by using a selective organic acid extracting agent. The invention is also directed to high silica crystalline zeolites prepared by the present process.
    Type: Grant
    Filed: July 5, 1989
    Date of Patent: May 28, 1991
    Assignee: Exxon Research & Engineering Company
    Inventors: Stephen M. Davis, W. Scott Varnado
  • Patent number: 4762959
    Abstract: A zirconium, hafnium, cerium or uranium promoted cobalt catalyst and process for the conversion of methanol or synthesis gas to hydrocarbons. Methanol is contacted, preferably with added hydrogen, over said catalyst, or synthesis gas is contacted over said catalyst to produce, at reaction conditions, an admixture of C.sub.10 + linear paraffins and olefins. These hydrocarbons can be further refined to high quality middle distillate fuels, and other valuable products such as mogas, diesel fuel, and jet fuel, particularly premium middle distillate fuels of carbon number ranging to about C.sub.20.
    Type: Grant
    Filed: June 4, 1987
    Date of Patent: August 9, 1988
    Assignee: Exxon Research and Engineering Company
    Inventors: Charles H. Mauldin, Stephen M. Davis, Kym B. Arcuri
  • Patent number: 4755536
    Abstract: A zirconium, hafnium, cerium or uranium promoted cobalt catalyst and process for the conversion of methanol or synthesis gas to hydrocarbons. Methanol is contacted, preferably with added hydrogen, over said catalyst, or synthesis gas is contacted over said catalyst to produce, at reaction conditions, an admixture of C.sub.10 + linear paraffins and olefins. These hydrocarbons can be further refined to high quality middle distillate fuels, and other valuable products such as mogas, diesel fuel, and jet fuel, particularly premium middle distillate fuels of carbon number ranging to about C.sub.20.
    Type: Grant
    Filed: October 24, 1986
    Date of Patent: July 5, 1988
    Assignee: Exxon Research and Engineering Co.
    Inventors: Charles H. Mauldin, Stephen M. Davis, Kym B. Arcuri
  • Patent number: 4663305
    Abstract: A zirconium, hafnium, cerium or uranium promoted cobalt catalyst and process for the conversion of methanol or synthesis gas to hydrocarbons. Methanol is contacted, preferably with added hydrogen, over said catalyst, or synthesis gas is contacted over said catalyst to produce, at reaction conditions, an admixture of C.sub.10 + linear paraffins and olefins. These hydrocarbons can be further refined to high quality middle distillate fuels, and other valuable products such as mogas, diesel fuel, and jet fuel, particularly premium middle distillate fuels of carbon number ranging to about C.sub.20.
    Type: Grant
    Filed: December 27, 1985
    Date of Patent: May 5, 1987
    Assignee: Exxon Research and Engineering Company
    Inventors: Charles H. Mauldin, Stephen M. Davis, Kym B. Arcuri
  • Patent number: 4369090
    Abstract: A method for the fabrication of a cured polyamic acid film having apertures therein selectively etched to provide sidewalls sloped at a controlled angle. Such films are used in the fabrication of integrated circuits having two or more levels of metallization, to provide electrical insulation between metal levels. The apertures therein are required to have sloped sidewalls in order to enhance the yields of circuits having reliable contact between metal levels.
    Type: Grant
    Filed: November 6, 1980
    Date of Patent: January 18, 1983
    Assignee: Texas Instruments Incorporated
    Inventors: Arthur M. Wilson, David W. Laks, Stephen M. Davis