Patents by Inventor Velliyur Nott Rao

Velliyur Nott 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).

  • Publication number: 20090005618
    Abstract: The present disclosure related to azeotrope and near-azeotrope compositions comprising PFC-C318 and HFC-236cb. The present disclosure further relates to processes for removing PFC-C318 from HFC-236cb. And the present disclosure further relates to azeotrope and near azeotrope compositions comprising hydrogen fluoride and PFC-C318.
    Type: Application
    Filed: February 19, 2008
    Publication date: January 1, 2009
    Applicant: E. I. du Pont de Nemours and Company
    Inventors: Velliyur Nott Rao, Jeffrey P. Knapp
  • Publication number: 20070123742
    Abstract: A process for the manufacture of CF3CH2CHF2 and CF3CH2CF3 is disclosed. The process involves (a) reacting HF and at least one halopropene of the formula CX3CCl?CClX (where each X is independently F or Cl) to produce a product including both CF3CCl?CF2 and CF3CHClCF3; (b) reacting CF3CCl?CF2 and CF3CHClCF3 produced in (a) with hydrogen to produce a product including both CF3CH2CHF2 and CF3CH2CF3; and (c) recovering CF3CH2CHF2 and CF3CH2CF3 from the product produced in (b). In (a), the CF3CCl?CF2 and CF3CHClCF3 are produced in the presence of a fluorination catalyst including a ZnCr2O4/crysta ?-chromium oxide composition, a ZnCr2O4/crystalline ?-chromium oxide composition which has been treated with a flourinating a agent, a zinc halide/?-chromium oxide composition and/or a zinc halide?-chromium oxide composition which has been treated with a fluorinating agent.
    Type: Application
    Filed: October 13, 2004
    Publication date: May 31, 2007
    Inventors: Velliyur Nott Rao, Allen Sievert
  • Publication number: 20070100175
    Abstract: Disclosed herein are azeotrope or near-azeotrope compositions comprising 2,3,3,3-tetrafluoropropene (HFC-1234yf) and hydrogen fluoride (HF). These compositions are useful in processes to produce and purify HFC-1234yf. Additionally, disclosed herein are processes for the manufacture of HFC-1234yf.
    Type: Application
    Filed: October 31, 2006
    Publication date: May 3, 2007
    Inventors: Ralph Miller, Mario Nappa, Velliyur Nott Rao, Allen Sievert
  • Publication number: 20070099811
    Abstract: Disclosed herein are azeotrope compositions comprising 1,2,3,3,3-pentafluoropropene and hydrogen fluoride. The azeotrope compositions are useful in processes to produce and in processes to purify 1,2,3,3,3-pentafluoropropene. Additionally, disclosed herein are azeotrope and near-azeotrope compositions comprising 1,1,1,2,3,4,4,5,5,5-decafluoropentane and hydrogen fluoride.
    Type: Application
    Filed: October 31, 2006
    Publication date: May 3, 2007
    Inventors: Ralph Miller, Mario Nappa, Velliyur Nott Rao, Allen Sievert
  • Publication number: 20070100174
    Abstract: Disclosed herein are azeotrope compositions comprising 1,2,3,3,3-pentafluoropropene and hydrogen fluoride. The azeotrope compositions are useful in processes to produce and in processes to purify 1,2,3,3,3-pentafluoropropene.
    Type: Application
    Filed: October 30, 2006
    Publication date: May 3, 2007
    Inventors: Ralph Miller, Barbara Minor, Mario Nappa, Velliyur Nott Rao, Allen Sievert
  • Publication number: 20070100176
    Abstract: Disclosed herein are azeotrope and near-azeotrope compositions comprising 1,1,1,2,2,4,5,5,6,6,7,7,7-tridecafluoro-3-heptene (HFC-162-13mczy, CF3CF2CH?CFCF2CF2CF3) and 1,1,1,2,2,3,5,5,6,6,7,7,7-tridecafluoro-3-heptene (HFC-162-13mcyz, CF3CF2CF?CHCF2CF2CF3) and hydrogen fluoride (HF) and to azeotrope and near-azeotrope compositions comprising 1,1,1,2,2,3,4,5,5,6,6,7,7,7-tetradecafluoroheptane and hydrogen fluoride (HF). These compositions are useful in processes to produce and purify HFC-162-13mcyz, HFC-162-13mczy and HFC-63-14mee.
    Type: Application
    Filed: October 31, 2006
    Publication date: May 3, 2007
    Inventors: Ralph Miller, Mario Nappa, Velliyur Nott Rao, Allen Sievert
  • Publication number: 20070100173
    Abstract: Disclosed herein are azeotrope and near-azeotrope compositions comprising E-1,3,3,3-tetrafluoropropene and hydrogen fluoride. These azeotrope and near-azeotrope compositions are useful in processes to produce E-1,3,3,3-tetrafluoropropene and in processes to purify E-1,3,3,3-tetrafluoropropene from mixtures of E-1,3,3,3-tetrafluoropropene with 1,1,1,3,3-pentafluoropropane and/or with hydrogen fluoride.
    Type: Application
    Filed: October 30, 2006
    Publication date: May 3, 2007
    Inventors: Ralph Miller, Mario Nappa, Velliyur Nott Rao, Allen Sievert
  • Publication number: 20060258890
    Abstract: A process is disclosed for the manufacture of 1,1,1,3,3,3-hexafluoropropane (HFC-236fa) and at least one 1,1,1,2,3,3-hexafluoropropane (HFC-236ea) and 1,1,1,2,3,3,3-heptafluoropropane (HFC-227ea). The process involves (a) reacting HF, Cl2, and at least one halopropene of the formula CX3CCl?CX2 (where each X is independently F or Cl) to produce a product including both CF3CCl2CF3 and CF3CClFCClF2; (b) reacting CF3CCl2CF3 and CF3CClFCClF2 produced in (a) with hydrogen to produce a product comprising CF3CH2CF3 and at least one compound selected from the group consisting of CHF2CHFCF3, and CF3CHFCH3; and (c) recovering from the product produced in (b), CF3CH2CF3 and at least one compound selected from the group consisting of CHF2CHFCF3 and CF3CHFCF3.
    Type: Application
    Filed: October 13, 2004
    Publication date: November 16, 2006
    Inventors: Velliyur Nott Rao, Allen Sievert
  • Publication number: 20060004235
    Abstract: A process for the preparation of pentafluoroethane is disclosed which involves contacting a mixture comprising hydrogen fluoride and at least one one starting material selected from haloethanes of the formula CX3191CHX2 and haloethenes of the formula CX2?CX2, where each X is independently selected from the group consisting of F and Cl (provided that no more than four of X are F), with a fluorination catalyst in a reaction zone to produce a product mixture comprising HF, HCl, pentafluoroethane, underfluorinated halogenated hydrocarbon intermediates and less than 0.2 mole percent chloropentafluoroethane based on the total moles of halogenated hydrocarbons in the product mixture. The process is characterized by the fluorination catalyst comprising (i) a crystalline cobalt-substituted alpha-chromium oxide where from about 0.05 atom % to about 6 atom % of the chromium atoms in the alpha-chromium oxide lattice are replaced by trivalent cobalt (Co3) and/or (ii) a fluorinated crystalline oxide of (i).
    Type: Application
    Filed: August 21, 2003
    Publication date: January 5, 2006
    Inventors: Mario Nappa, Velliyur Nott Rao, H. Rosenfeld, Shekhar Subramoney, Munirpallam Subramanian, Allen Sievert
  • Publication number: 20050228202
    Abstract: A crystalline alpha-chromium oxide where from about 0.05 atom % to about 6 atom % of the chromium atoms in the alpha-chromium oxide lattice are replaced by trivalent cobalt (Co+3) atoms is disclosed. Also disclosed is a chromium-containing catalyst composition comprising as a chromium-containing component the crystalline cobalt-substituted alpha-chromium oxide; and a method for preparing a composition comprising the crystalline cobalt-substituted alpha-chromium oxide. The method involves (a) co-precipitating a solid by adding ammonium hydroxide to an aqueous solution of a soluble cobalt salt and a soluble trivalent chromium salt that contains at least three moles of nitrate per mole of chromium in the solution and has a cobalt concentration of from about 0.
    Type: Application
    Filed: August 21, 2003
    Publication date: October 13, 2005
    Inventors: Mario Nappa, Velliyur Nott Rao, H. Rosenfeld, Shekhar Subramoney, Munirpallam Subramanian, Allen Sievert
  • Publication number: 20050222471
    Abstract: A process for the preparation of 2-chloro-1,1,1,3,3,3-heptafluoropropane is disclosed which involves (a) contacting a mixture comprising hydrogen fluoride, chlorine, and at least one starting material selected from the group consisting of halopropenes of the formula CX3CCl?CX2 and halopropanes of the formula the CX3CClYCX3, wherein each X is independently F or Cl, and Y is H, Cl or F (provided that the number of X and Y which are F totals no more than six) with a chlorofluorination catalyst in a reaction zone to produce a product mixture comprising CF3CClFCF3, HCl, HF, and underfluorinated halogenated hydrocarbon intermediates. The process is characterized by said chlorofluorination catalyst comprising at least one chromium-containing component selected from (i) a crystalline alpha-chromium oxide where at least 0.
    Type: Application
    Filed: August 21, 2003
    Publication date: October 6, 2005
    Inventors: Mario Nappa, Velliyur Nott Rao, H. Rosenfeld, Shekhar Subramoney, Munirpallam Subramanian, Allen sievert