Patents Examined by Thuan Dang
  • Patent number: 6660896
    Abstract: In a process for isomerizing a feed comprising ethylbenzene and a mixture of xylene isomers, the feed is first contacted under xylene isomerization conditions with a first catalyst composition to produce an intermediate product having a higher para-xylene concentration than the feed, and then the intermediate product is contacted under ethylbenzene isomerization conditions with a second catalyst composition. The second catalyst composition comprises a hydrogenation-dehydrogenation component and a molecular sieve having 10-membered ring pores and is effective to selectively isomerize at least part of the ethylbenzene in the intermediate product to para-xylene and thereby produce a further product having a para-xylene concentration greater than the equilibrium concentration of para-xylene at said ethylbenzene isomerization conditions.
    Type: Grant
    Filed: April 16, 2003
    Date of Patent: December 9, 2003
    Assignee: ExxonMobil Chemical Patents Inc.
    Inventors: John Scott Buchanan, Xiaobing Feng, Gary David Mohr, David L. Stern
  • Patent number: 6566569
    Abstract: A process for preparing a C4- product stream and a C6+ product stream is disclosed. The process involves contacting a C5 containing paraffinic feedstock with a catalyst that includes a hydrogenation/dehydrogenation catalyst and an olefin metathesis catalyst under conditions which dehydrogenate the paraffins to olefins. The olefins are then metathesized and rehydrogenated to provide a product stream. A C4- fraction and a C6+ fraction can each be isolated from the product stream. The C4- fraction can be used, for example, in an alkylation reaction to provide compounds useful in gasoline compositions. Unconverted C5 paraffins can be recycled. The C6+ fraction can be used, for example, as solvents. Alternatively, they can be isomerized to form gasoline additives, or can be converted to aromatic compounds via reforming, for example, using conventional reforming techniques, preferably using the AROMAX™ process or traditional rheniforming conditions.
    Type: Grant
    Filed: June 23, 2000
    Date of Patent: May 20, 2003
    Assignee: Chevron U.S.A. Inc.
    Inventors: Cong-Yan Chen, Dennis J. O'Rear, Scott R. Brundage
  • Patent number: 6512155
    Abstract: An improved process is disclosed for ethylbenzene and xylene isomerization in a non-equilibrium mixture of xylenes and ethylbenzene. By addition of trace quantities of water to the reaction zone, equivalent isomerization is effected at lower temperatures wherein benefits could be realized in reduced losses and improved catalyst life.
    Type: Grant
    Filed: April 25, 2000
    Date of Patent: January 28, 2003
    Assignee: UOP LLC
    Inventors: James A. Johnson, Benjamin D. Riley, Sanjay B. Sharma, Patrick J. Silady, Gail L. Gray
  • Patent number: 6504072
    Abstract: There is provided a process for the selective production of para-xylene which comprises reacting toluene with methanol in the presence of a catalyst comprising a porous crystalline material having a Diffusion Parameter for 2,2 dimethylbutane of about 0.1-15 sec−1 when measured at a temperature of 120° C. and a 2,2 dimethylbutane pressure of 60 torr (8 kPa). The porous crystalline material is preferably a medium-pore zeolite, particularly ZSM-5, which has been severely steamed at a temperature of at least 950° C. The porous crystalline material is preferably combined with at least one oxide modifier, preferably including phosphorus, to control reduction of the micropore volume of the material during the steaming step.
    Type: Grant
    Filed: May 8, 2002
    Date of Patent: January 7, 2003
    Assignee: ExxonMobil Oil Corporation
    Inventors: Stephen H. Brown, Mark F. Mathias, Robert A. Ware, David H. Olson
  • Patent number: 6464856
    Abstract: An improved process for the total separation and recovery of four constituents, namely, 1) insoluble pitches and tars also known as asphaltenes, 2) a kerosene based oil fraction, 3) clays and silts of less than 80 &mgr;m mesh and 4) sands of greater than 80 &mgr;m mesh. Recombination of the hydrocarbon fractions is the bitumen portion of tar sands. A further process for the extraction and separation of plant resins from cellulose and kerogen from oil shale that on thermal depolymerization become a source for aromatic and kerosene based oil fractions respectively.
    Type: Grant
    Filed: August 22, 2000
    Date of Patent: October 15, 2002
    Assignee: Deinking/ Solvent Extraction Technologies
    Inventor: Venanzio Di Tullio
  • Patent number: 6462245
    Abstract: A method for polymerizing an alkyl-substituted aromatic compound comprises reacting the alkyl-substituted aromatic compound in the presence of a molecular sieve such that the aromatic compound polymerizes.
    Type: Grant
    Filed: April 6, 2001
    Date of Patent: October 8, 2002
    Assignee: British Nuclear Fuels plc
    Inventor: Darren Frank Lee
  • Patent number: 6127590
    Abstract: This invention relates generally to the field of chemical synthesis, and more specifically, to the field of oxidative coupling of olefinic compounds and aromatic compounds, to produce olefinically substituted aromatic compounds. More particularly, this invention relates to methods for oxidative coupling of olefinic compounds and aromatic compounds which employ a rhodium(III) acetylacetonate catalyst and a copper(II) redox agent in a reaction medium which does not comprise a carboxylic acid component. In one embodiment, this invention pertains to methods for the preparation of styrene by the oxidative coupling of ethylene (an olefinic compound) and benzene (an aromatic compound), in the presence of Rh(acac).sub.2 Cl(H.sub.2 O), as catalyst, and Cu(II)(CH.sub.3 COO).sub.2, as copper(II) redox agent, in which benzene is both a reactant and the reaction medium.
    Type: Grant
    Filed: March 26, 1999
    Date of Patent: October 3, 2000
    Assignee: Nippon Mitsubishi Oil Corporation
    Inventors: Douglas Taube, Roy Periana, Takaya Matsumoto
  • Patent number: 5958218
    Abstract: Hydrocarbon feedstocks are hydroprocessed in parallel reactors, while hydrogen flows in series between the reactors. A first hydrocarbon feedstock and a hydrogen-rich recycle gas stream are introduced to a first reactor, where a first reactor effluent stream is produced and fed to a first separator, which separates the first reactor effluent stream into a first hydrogen-rich gas stream and a first hydroprocessed product stream. The first hydrogen-rich gas stream and a second hydrocarbon feedstock are fed to a second reactor, where a second reactor effluent stream is produced and fed to a second separator, which separates the second reactor effluent stream into a second hydrogen-rich gas stream and a second hydroprocessed product stream. A make-up hydrogen stream is added to the second hydrogen-rich gas to form the hydrogen-rich recycle gas stream that is compressed and fed to the first reactor.
    Type: Grant
    Filed: January 22, 1996
    Date of Patent: September 28, 1999
    Assignee: The M. W. Kellogg Company
    Inventors: Michael G. Hunter, Kenneth W. Goebel
  • Patent number: 5849964
    Abstract: A process is disclosed for processing used or waste plastic materials in order to recover chemical raw materials and liquid fuel components by depolymerisation of the used materials, which are transformed into a pumpable and into a volatile phase. The volatile phase is separated into a gaseous phase and a condensate or condensable depolymerisation product, which are refined by standard usual procedures. The pumpable phase remaining once the volatile phase is separated is subjected to liquid phase hydrogenation, gasification, low temperature carbonisation or to a combination of said processes.
    Type: Grant
    Filed: December 27, 1995
    Date of Patent: December 15, 1998
    Assignee: Veba Oel Aktiengesellschaft
    Inventors: Rolf Holighaus, Klaus Niemann, Martin Rupp