Patents by Inventor Sara W. Boehmer

Sara W. Boehmer 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).

  • Purification of difluoromethane by extractive distillation
    Patent number: 7371309
    Abstract: The present invention provides extractive distillation processes for removing difluoromethane (HFC-32) from a mixture comprising HFC-32 and at least one of chlorodifluoromethane (CFC-12), 1,1,1-trifluoroethane (HFC-143a), chloropentafluoroethane (CFC-115), and pentafluoroethane (HFC-125) using hydrocarbon, chlorocarbon, and oxygen-containing extractive agents.
    Type: Grant
    Filed: August 12, 1998
    Date of Patent: May 13, 2008
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Sara W. Boehmer, Barry Asher Mahler, Ralph Newton Miller
  • PURIFICATION OF DIFLUOROMETHANE BY EXTRACTIVE DISTILLATION
    Publication number: 20030116422
    Abstract: The present invention provides extractive distillation processes for removing difluoromethane (HFC-32) from a mixture comprising HFC-32 and at least one of chlorodifluoromethane (CFC-12), 1,1,1-trifluoroethane (HFC-143a), chloropentafluoroethane (CFC-115), and pentafluoroethane (HFC-125) using hydrocarbon, chlorocarbon, and oxygen-containing extractive agents.
    Type: Application
    Filed: February 11, 2000
    Publication date: June 26, 2003
    Inventors: SARA W. BOEHMER, BARRY ASHER MAHLER, RALPH NEWTON MILLER
  • Separating 1,1,1,3,3-pentafluoropropane from hydrogen fluoride
    Patent number: 6303838
    Abstract: Disclosed are processes for separating 1,1,1,3,3-pentafluoropropane (HFC-245fa) from hydrogen fluoride (HF) by distillation, wherein hydrocarbons, chloroflurocarbons, hydrochlorofluorocarbons and fluorocarbons are used as entraining agents. The processes comprise: contacting a first mixture comprising HFC-245fa and HF with an entraining agent selected from the group consisting of hydrocarbons, chlorofluorocarbons, hydrochlorofluorocarbons and fluorocarbons to form a second mixture, distilling the second mixture and thereby separating the HFC-245fa from HF and entraining agent, and recovering HFC-245fa substantially-free of HF.
    Type: Grant
    Filed: March 31, 2000
    Date of Patent: October 16, 2001
    Assignee: E.I. du Pont de Nemours and Company
    Inventors: Sara W. Boehmer, Barry Asher Mahler, Ralph Newton Miller