Patents by Inventor Krishna Kulai Rao

Krishna Kulai Rao 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: 8288596
    Abstract: Acetals are formed from an aldehyde hydrogenation product mixture comprising alcohols and at most 2% of alde-hydes and the product is distilled to yield purified alcohols and a second stream containing acetals and/or unsaturated ethers.
    Type: Grant
    Filed: February 27, 2008
    Date of Patent: October 16, 2012
    Assignee: ExxonMobil Chemical Patents Inc.
    Inventors: Ronald Dean Garton, Corey W. Reed, Krishna Kulai Rao, Bruce D. Lilly, Ramzi Yanni Saleh, Raphael Frans Caers
  • Patent number: 7179367
    Abstract: A process for reforming wherein ethylbenzene formed during the reforming is converted to xylenes. The process is carried out by reforming a feed containing precursors of ethylbenzene with a reforming catalyst under conditions effective to reform said feed; wherein the reforming catalyst is contained in a reactor which contains a second catalyst effective under said conditions to convert ethylbenzene to xylenes. The resulting product contains reduced amounts of ethylbenzene and increased amounts of xylenes.
    Type: Grant
    Filed: July 1, 2003
    Date of Patent: February 20, 2007
    Assignee: ExxonMobil Chemical Patents Inc.
    Inventors: Xiaobing Feng, Jain-Kai Hung, Gary D. Mohr, Krishna Kulai Rao
  • Patent number: 7067052
    Abstract: A process for reforming a hydrocarbon feed containing precursors of ethylbenzene, e.g., C8 isoalkane and/or C8 isoalkene precursors of ethylbenzene, that results in the formation of reduced amounts of ethylbenzene. The process is carried out in a catalytic reforming unit comprised of a plurality of operatively connected reactors comprising at least one lead reforming reactor and a tail reforming reactor. The process is carried out by reforming the feed in at least one lead reactor which contains a first reforming catalyst and a catalyst effective for converting ethylbenzene and further reforming the product of the lead reactor in the tail reactor that contains a second reforming catalyst.
    Type: Grant
    Filed: July 1, 2003
    Date of Patent: June 27, 2006
    Assignee: ExxonMobil Chemical Patents Inc.
    Inventors: Jain-Kai Hung, Thomas H. Colle, Xiaobing Feng, Gary D. Mohr, Krishna Kulai Rao
  • Patent number: 6642407
    Abstract: This invention provides a process for purifying the crude aromatic dicarboxylic acids produced by oxidation of dialkyl aromatic hydrocarbons and for using the purified acids in the preparation of polyethylene terephthalate, polyethylene naphthalate and other polyesters. The invention simplifies the manufacturing process by converting the crude aromatic acids into bis-glycol esters in an esterification reactor 4, from which the esterified partial oxidation impurities present in the oxidation product are removed by distillation in distillation tower 5. After removal of the volatile impurities, the dicarboxylic acid esters can separated by distillation in distillation tower 6 or by crystallization and converted to polyesters by polycondensation. The volatile impurities removed as overhead from tower 5 can be recycled as stream 16 to the oxidation reactor where they act as oxidation promoters thereby optionally allowing for a bromine-free oxidation process for dialkyl aromatic hydrocarbons.
    Type: Grant
    Filed: April 26, 2002
    Date of Patent: November 4, 2003
    Assignee: Exxon Mobil Chemical Patents Inc.
    Inventors: Krishna Kulai Rao, Russell D. Sellen, Xiaobing Feng, James Spanswick, William F. Huber, Jr.
  • Publication number: 20020173674
    Abstract: This invention provides a process for purifying the crude aromatic dicarboxylic acids produced by oxidation of dialkyl aromatic hydrocarbons and for using the purified acids in the preparation of polyethylene terephthalate, polyethylene naphthalate and other polyesters. The invention simplifies the manufacturing process by converting the crude aromatic acids into bis-glycol esters in an esterification reactor 4, from which the esterified partial oxidation impurities present in the oxidation product are removed by distillation in distillation tower 5. After removal of the volatile impurities, the dicarboxylic acid esters can separated by distillation in distillation tower 6 or by crystallization and converted to polyesters by polycondensation. The volatile impurities reoved as overhead from tower 5 can be recycled as stream 16 to the oxidation reactor where they act as oxidation promoters thereby optionally allowing for a bromine-free oxidation process for dialkyl aromatic hydrocarbons.
    Type: Application
    Filed: April 26, 2002
    Publication date: November 21, 2002
    Inventors: Krishna Kulai Rao, Russell D. Sellen, Xiaobing Feng, James Spanswick, William F. Huber
  • Publication number: 20020173673
    Abstract: This invention provides a process for purifying the crude aromatic dicarboxylic acids produced by oxidation of dialkyl aromatic hydrocarbons and for using the purified acids in the preparation of polyethylene terephthalate, polyethylene naphthalate and other polyesters. The invention simplifies the manufacturing process by converting the crude aromatic acids into bis-glycol esters in an esterification reactor 4, from which the esterified partial oxidation impurities present in the oxidation product are removed by distillation in distillation tower 5. After removal of the volatile impurities, the dicarboxylic acid esters can separated by distillation in distillation tower 6 or by crystallization and converted to polyesters by polycondensation. The volatile impurities reoved as overhead from tower 5 can be recycled as stream 16 to the oxidation reactor where they act as oxidation promoters thereby optionally allowing for a bromine-free oxidation process for dialkyl aromatic hydrocarbons.
    Type: Application
    Filed: May 18, 2001
    Publication date: November 21, 2002
    Inventors: Krishna Kulai Rao, Russell D. Sellen, Xiaobing Feng