Patents by Inventor Mario J. Nappa

Mario J. Nappa 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: 7074973
    Abstract: A process for the preparation of pentafluoroethane is disclosed which involves contacting a mixture comprising hydrogen fluoride and at least one starting material selected from haloethanes of the formula CX3CHX2 and haloethanes 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 (Co+3) and/or (ii) a fluorinated crystalline oxide of (i).
    Type: Grant
    Filed: August 21, 2003
    Date of Patent: July 11, 2006
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Mario J. Nappa, Velliyur Nott Mallikarjuna Rao, H. David Rosenfeld, Shekhar Subramoney, Munirpallam A. Subramanian, Allen C. Sievert
  • Patent number: 7029599
    Abstract: Disclosed herein are 1,1,1,3,3-pentafluorobutane refrigerant or heat transfer fluid compositions further comprising fluoroether, which are useful in refrigerain or air conditioning apparatus or as heat transfer fluids. The compositions of the present invention are also useful in centrifugal compressor apparatus that employ two-stage compressors or single slab.single pass heat exchangers.
    Type: Grant
    Filed: December 16, 2004
    Date of Patent: April 18, 2006
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Barbara Haviland Minor, Mario J. Nappa, Allen C. Sievert
  • Patent number: 6900362
    Abstract: A process for the production of HFC-227ea from HF and HFP is provided. This process takes advantage of an azeotropic composition of HF and HFC-227ea in order to produce HFC-227ea essentially free of HF and recycle unreacted HF back to the reactor. The recycle of said azeotropic composition, also allows the use of HFC-227ea as a diluent to aid in control of reactor temperature for a highly exothermic reaction.
    Type: Grant
    Filed: October 31, 2002
    Date of Patent: May 31, 2005
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Ralph Newton Miller, Mario J. Nappa, Donald J. Toton
  • Publication number: 20040191155
    Abstract: The concentration of undesirable impurities dinitrogen difluoride and dinitrogen tetrafluoride in a nitrogen trifluoride mixture are reduced by heating the mixture in the gas phase in a vessel with an inner wall selected from electropolished metal, ceramic alumina or sapphire, and recovering a nitrogen trifluoride product having reduced concentration of such impurities. The process is preferably carried out at a temperature of at least about 150° C. to about 300° C. and the vessel is preferrably free of packing and has a minimized ratio of the vessel interior surface area to vessel volume in the region of the vessel where the heating step is carried out. The process optionally may further include the step of contacting the inner wall of the vessel with a passivating composition comprising fluorine gas.
    Type: Application
    Filed: March 25, 2003
    Publication date: September 30, 2004
    Inventors: Barry Asher Mahler, Mario J. Nappa
  • Publication number: 20030088132
    Abstract: A process for the production of HFC-227ea from HF and HFP is provided. This process takes advantage of an azeotropic composition of HF and HFC-227ea in order to produce HFC-227ea essentially free of HF and recycle unreacted HF back to the reactor. The recycle of said azeotropic composition, also allows the use of HFC-227ea as a diluent to aid in control of reactor temperature for a highly exothermic reaction.
    Type: Application
    Filed: October 31, 2002
    Publication date: May 8, 2003
    Inventors: Ralph Newton Miller, Mario J. Nappa, Donald J. Toton
  • Patent number: 5488189
    Abstract: The instant invention relates to producing fluorinated propanes and pentanes. More particularly it relates to producing perhalofluoropropanes and pentanes by reacting dihalodifluoromethanes with polyfluoroethylenes, notably tetrafluoroethylene (TFE) and chlorotrifluoroethylene (CTFE) while in the presence of an aluminum chlorofluoride catalyst.
    Type: Grant
    Filed: December 14, 1993
    Date of Patent: January 30, 1996
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Allen C. Sievert, Mario J. Nappa
  • Patent number: 5475167
    Abstract: A process is disclosed for the preparation of pentafluoroethane from chlorotetrafluoroethane (the yield of pentafluoroethane is at least 50 mole percent based upon the amount of chlorofluoroethane reacted with HF) with particularly low levels of chlorofluoroethanes. The process involves providing sufficient pretreatment (where necessary) of a Cr.sub.2 O.sub.3 catalyst with at least one agent selected from the group consisting of CO, H.sub.2, H.sub.2 O and mixtures thereof in the gaseous state such that the total chlorofluoroethane content of said product stream is less than 1 mole percent. Certain high surface area catalysts may be used without such pretreatment.
    Type: Grant
    Filed: February 17, 1995
    Date of Patent: December 12, 1995
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Mario J. Nappa, V. N. Mallikarjuna Rao, William R. Williams
  • Patent number: 5457215
    Abstract: A reaction of perfluoroolefins with bis(silyl) ethers to produce novel partially fluorinated and perfluorinated copolymers and macrocyclic compounds is disclosed.
    Type: Grant
    Filed: July 5, 1994
    Date of Patent: October 10, 1995
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: William B. Farnham, Mario J. Nappa
  • Patent number: 5414165
    Abstract: A process is disclosed for producing 1,1,1,3,3,3-hexafluoropropane with high selectivity. 1,1,1,3,3,3-hexachloropropane is contacted with hydrogen fluoride in the vapor phase at a temperature of from about 200.degree. C. to 400.degree. C. in the presence of a catalyst comprising trivalent chromium, to produce a fluorinated product containing CF.sub.3 CH.sub.2 CF.sub.3 and its haloprecursors (i.e., compounds which may be recycled for further reaction with HF) with a total selectivity of at least about 95 percent; and a sufficient amount of said haloprecursors is reacted with hydrogen fluoride in the vapor phase at a temperature of from 200.degree. C. to 400.degree. C. in the presence of a catalyst comprising trivalent chromium to provide an overall selectivity to 1,1,1,3,3,3-hexafluoropropane of at least about 95 percent based upon the amount of 1,1,1,3,3,3-hexachloropropane initially reacted with HF.
    Type: Grant
    Filed: July 29, 1994
    Date of Patent: May 9, 1995
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Mario J. Nappa, Allen C. Sievert
  • 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: 5396000
    Abstract: A process is disclosed for producing CF.sub.3 CHFCH.sub.2 F using vapor phase catalytic dehydrohalogenation to produce CF.sub.3 CF.dbd.CHF and HF, followed by vapor phase catalytic hydrogenation of CF.sub.3 CF.dbd.CHF in the presence of HF.
    Type: Grant
    Filed: May 24, 1993
    Date of Patent: March 7, 1995
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Mario J. Nappa, V. N. Mallikarjuna Rao
  • Patent number: 5395999
    Abstract: A chlorofluorination process is disclosed which employs a catalyst comprising chromium oxide for producing halohydrocarbons of the formula CHXFCF.sub.3 (where X is selected from Cl and F). The process is characterized by feeding a combination of components comprising (i) at least one halohydrocarbon starting compound selected from CHCl.dbd.CCl.sub.2 and CH.sub.2 ClCF.sub.3, (ii) hydrogen fluoride and (iii) chlorine, to a reaction zone; contacting said combination of compounds in said reaction zone with a catalyst comprising chromium oxide at an elevated temperature to produce reaction zone products containing halohydrocarbons of the formula CHXFCF.sub.3 together with halohydrocarbon reaction products of the formula CHYClCF.sub.3 (wherein Y is selected from Cl and H); and recovering at least a portion of the reaction zone products from the reaction zone including at least one halohydrocarbon of the formula CHXFCF.sub.3.
    Type: Grant
    Filed: October 20, 1993
    Date of Patent: March 7, 1995
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Mario J. Nappa, V. N. Mallikarjuna Rao
  • Patent number: 5283382
    Abstract: Process for the preparation of fluorinated alkanes by contacting a starting material of halogenated alkene or alkane with 1 to 150 molar equivalents based on catalyst of HF, 1 to 30 molar equivalents based on catalyst of a dehydrating agent and less than 100 molar equivalents based on catalyst of a starting material, the catalyst being selected from niobium oxide or tantalum oxide, at a temperature of 0.degree. C. to 185.degree. C. The preferred dehydrating agent is a combination of chlorosulfonic acid and thionyl chloride.
    Type: Grant
    Filed: October 23, 1992
    Date of Patent: February 1, 1994
    Assignee: E. I. du Pont de Nemours and Company
    Inventor: Mario J. Nappa
  • 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: 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: 5258561
    Abstract: A chlorofluorination process is disclosed which employs a catalyst comprising chromium oxide for producing halohydrocarbons of the formula CHXFCF.sub.3 (where X is selected from Cl and F). The process is characterized by feeding a combination of components comprising, (i) at least one halohydrocarbon starting compound of the formula CY.sub.3 CH.sub.2 R.sup.1 (where R.sup.1 is selected from the group of H and F and each Y is independently selected from the group of Cl and F), (ii) hydrogen fluoride and (iii) chlorine to a reaction zone; contacting said combination of compounds in said reaction zone with a catalyst comprising chromium oxide at an elevated temperature to produce reaction zone products containing halohydrocarbon reaction products of the formula CHXFCF.sub.3 together with halohydrocarbons of the formula CZ.sub.3 CHR.sup.2 R.sup.3 (wherein R.sup.2 is selected from the group of H and Cl, R.sup.
    Type: Grant
    Filed: November 6, 1992
    Date of Patent: November 2, 1993
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Mario J. Nappa, V. N. Mallikarjuna Rao
  • Patent number: 5243025
    Abstract: A reaction of perfluoroolefins with bis(silyl) ethers to produce novel partially fluorinated and perfluorinated copolymers and macrocyclic compounds is disclosed.
    Type: Grant
    Filed: January 23, 1991
    Date of Patent: September 7, 1993
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: William B. Farnham, Mario J. Nappa
  • Patent number: 5091168
    Abstract: A method of producing an anhydrous niobium or tantalum pentafluoride involving reacting the corresponding pentoxide or oxyhalide with an excess of anhydrous hydrogen fluoride in the presence of a sufficient dehydrating agent (e.g., COCl.sub.2, SOCl.sub.2 or SO.sub.2 Cl.sub.2) to react with any water formed. Such a process is useful to produce a catalyticallyactive anhydrous niobium or tantalum pentafluoride in essentially a single liquid phase reaction step.
    Type: Grant
    Filed: August 15, 1990
    Date of Patent: February 25, 1992
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Mario J. Nappa
  • 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