Patents by Inventor Allen C. Sievert

Allen C. Sievert 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: 5409625
    Abstract: Linear hydrofluorocarbons of the formula XCF.sub.2 (CF.sub.2).sub.n CH.sub.2 F where X is H or F, and n is 1 to 7 when X is H and 0 to 7 when X is F, are produced by a vapor phase catalytic reaction of HF with corresponding compounds of the formula XCF.sub.2 (CF.sub.2).sub.n CH.sub.2 OY where Y is --(CO)Cl or --SO.sub.2 Cl. Azeotropic compositions with HF (e.g., an azeotrope of CHF.sub.2 CF.sub.2 CH.sub.2 F and HF) are provided, and a portion of the linear hydrofluorocarbon product (e.g., a portion of the CHF.sub.2 CF.sub.2 CH.sub.2 F) may be recovered as an azeotropic composition and recycled.
    Type: Grant
    Filed: October 21, 1993
    Date of Patent: April 25, 1995
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Mario J. Nappa, V. N. Mallikarjuna Rao, Allen C. Sievert
  • Patent number: 5410095
    Abstract: A process for the manufacture of pentafluorodimethyl ether is disclosed which involves contacting at least one starting compound selected from the group consisting of compounds having a formula (CF.sub.3 OCF.sub.2 CO.sub.2)A and compounds having he formula (CF.sub.3 OCF.sub.2 CO.sub.2).sub.2 A' wherein A is selected from the group consisting of hydrogen, ammonium, alkali metals (e.g., sodium or potassium) and R (wherein R is a C.sub.1 to C.sub.4 alkyl group) and A' is an selected from the group consisting of alkaline-earth metals (e.g., magnesium or calcium), with at least one hydroxylic compound selected from the group consisting of water, mono-alcohols of the formula R'OH (wherein R' is a C.sub.1 to C.sub.12 straight or branched chain alkyl group) and alkanediols of the formula R" (OH).sub.2 (wherein R" is a C.sub.2 to C.sub.8 alkylene group) at temperature of about 120.degree. C. to 170.degree. C.
    Type: Grant
    Filed: July 29, 1994
    Date of Patent: April 25, 1995
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Paul R. Resnick, Allen C. Sievert
  • Patent number: 5406008
    Abstract: A process for the manufacture of hydrofluorocarbons by the reaction of selected relatively low modular weight saturated and unsaturated hydrocarbons and corresponding partially halogenated hydrocarbons with elemental fluorine in the vapor phase. By selecting the ratio of F.sub.2 / substrate in combination with reaction temperature and reactor residence time the extent of fluorination of a substrate and degree of overfluorination can be controlled. Thus, starting with 1,1,1-trifluoroethane, CH.sub.3 CF.sub.3 (HFC-143a), 1,1,1,2-tetrafluoroethane, CH.sub.2 FCF.sub.3 (HFC-134a) is produced by simple thermal fluorination even in the presence of simultaneous formation of pentafluoroethane HFC-125. The use of compounds highly reactive toward fluorine are shown to promote the selective fluorination of partially fluorinated substrates.
    Type: Grant
    Filed: December 28, 1989
    Date of Patent: April 11, 1995
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Allen C. Sievert
  • Patent number: 5336801
    Abstract: This invention relates to chemical processes for preparing tetrafluoropropionate salts and selected derivatives thereof.
    Type: Grant
    Filed: September 15, 1992
    Date of Patent: August 9, 1994
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Carl G. Krespan, Allen C. Sievert
  • Patent number: 5274189
    Abstract: This invention relates to a process for producing linear hydrofluorocarbons of the formula XCF.sub.2 (CF.sub.2).sub.n CH.sub.2 F, where X is H or F, and n is 1 to 7 when X is H, and n is 0 to 7 when X is F, by a vapor phase catalytic reaction of HF and phosgene or sulfuryl chloride with corresponding compounds of the formula XCF.sub.2 (CF.sub.2).sub.n CH.sub.2 OZ where Z is H or --C(O)OCH.sub.2 (CF.sub.2).sub.n CF.sub.2 X.
    Type: Grant
    Filed: May 24, 1993
    Date of Patent: December 28, 1993
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Mario J. Nappa, Allen C. Sievert
  • Patent number: 5274190
    Abstract: Linear hydrofluorocarbons of the formula XCF.sub.2 (CF.sub.2).sub.n CH.sub.2 F where X is H or F, and n is 1 to 7 when X is H and 0 to 7 when X is F, are produced by a vapor phase catalytic reaction of HF with corresponding compounds of the formula XCF.sub.2 (CF.sub.2).sub.n CH.sub.2 OY where Y is --(CO)Cl or --SO.sub.2 Cl.
    Type: Grant
    Filed: May 24, 1993
    Date of Patent: December 28, 1993
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Mario J. Nappa, Allen C. Sievert
  • Patent number: 5221493
    Abstract: Azeotropic mixtures of HFC-338pcc and an alcohol such as methanol, ethanol, isopropanol or N-propanol, or a ketone such as acetone, are disclosed that are useful as cleaning agents, refrigerants, aerosol propellants, heat transfer media, gaseous dielectrics, fire extinguishing agents, expansion agents for polyolefins and polyurethanes, power cycle working fluids, polymerization media, particulate removal fluids, carrier fluids, and displacement drying agents.
    Type: Grant
    Filed: October 18, 1991
    Date of Patent: June 22, 1993
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Abid N. Merchant, Allen C. Sievert, Akimichi Yokozeki, Janet C. Sung
  • Patent number: 5157171
    Abstract: A process for the preparation of chlorofluoropropanes of the formula C.sub.3 HCl.sub.2 F.sub.5 by contacting monofluorodichloromethane with tetrafluoroethylene in the presence of a modified aluminum chloride catalyst at a temperature of 0.degree. to 150.degree. C. The novel compound CF.sub.3 CCl.sub.2 CHF.sub.2 is also disclosed.
    Type: Grant
    Filed: April 5, 1991
    Date of Patent: October 20, 1992
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Allen C. Sievert, Carl G. Krespan, Frank J. Weigert
  • Patent number: 4960951
    Abstract: Novel perfluoropolyethers, such as perfluorodipentaerythritol hexaethyl ether, and their intermediates exhibit excellent chemical and thermal stability and are useful as vapor phase soldering fluids and convection cooling liquids.
    Type: Grant
    Filed: February 14, 1990
    Date of Patent: October 2, 1990
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Mario J. Nappa, Allen C. Sievert, Walter R. Tong
  • Patent number: H1188
    Abstract: A process for the preparation of 1,1-dichloro-1,2-difluoroethane (HCFC-132c) comprising contacting 1,1-dichloroethylene with lead dioxide and anhydrous hydrogen fluoride. Addition of fluorine to the double bond of vinylidene chloride can be achieved using inexpensive and readily available commercial raw materials.
    Type: Grant
    Filed: September 19, 1990
    Date of Patent: May 4, 1993
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Mario J. Nappa, Allen C. Sievert