Patents by Inventor Frederick W. Mader

Frederick W. Mader 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: 4990701
    Abstract: A process for halogen exchange fluorination by contacting a halocarbon having a replaceable halogen other than fluorine with KF.nHF wherein n is 0.5-3 to provide a fluorinated hydrocarbon having at least one more fluorine than the starting halocarbon and, optionally, regenerating the KF.nHF with additional HF, or in a continuous process, with excess HF in the feed.
    Type: Grant
    Filed: March 20, 1990
    Date of Patent: February 5, 1991
    Assignee: E. I. DuPont de Nemours and Company
    Inventors: Wendel R. Cassel, Richard E. Fernandez, Frederick W. Mader
  • Patent number: 4990702
    Abstract: A process for halogen exchange fluorination by contacting a halocarbon having a replaceable halogen other than fluorine with CsF or RbF.multidot.nHF wherein n is 0.5-3 to provide a fluorinated hydrocarbon having at least one more fluorine than the starting halocarbon and, optionally, regenerating the MF.multidot.nHF with additional HF, or in a continuous process, with excess HF in the feed.
    Type: Grant
    Filed: February 15, 1990
    Date of Patent: February 5, 1991
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Richard E. Fernandez, Wendel R. Cassel, Frederick W. Mader
  • Patent number: 4952291
    Abstract: An aldehyde in a mixture containing hemiacetals and hydrates of the aldehyde is purified by treating the mixture with an effective amount of microwave radiation to decompose the hemiacetals and hydrates. Liberated water and/or alcohol is immediately removed with an adsorbent.
    Type: Grant
    Filed: December 6, 1989
    Date of Patent: August 28, 1990
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Neville E. Drysdale, Frederick W. Mader, Rudolf E. Svadlenak
  • Patent number: 4885416
    Abstract: A continuous process for florinating haloalkanes containing at least one nonfluorine halogen atom wherein antimony pentachloride is reacted with HF to produce an antimony (V) chlorofluoride and HCl is removed. The antimony chlorofluoride thus produced is then transferred to a separate reaction zone where it is reacted with the haloalkane, thereby replacing a portion of the nonfluorine halogen in the haloalkane with fluorine of the antimony (V) chlorofluoride.
    Type: Grant
    Filed: February 9, 1988
    Date of Patent: December 5, 1989
    Assignee: E. I. Du Pont De Nemours and Company
    Inventor: Frederick W. Mader
  • Patent number: 4085518
    Abstract: Process of drying water-wet solid materials, which process comprises, in a system,A. forcibly contacting the water-wet solid material with circulating vapor of a fluorocarbon having a fluorine to carbon atom ratio of at least 1.0 and a boiling temperature of less than about 80.degree. C at atmospheric pressure, said fluorocarbon vapor being at a temperture above about 100.degree. C and said contacting being carried out in the absence of a substantial amount of a noncondensable gas, such as air or nitrogen,B. passing the resulting mixture of fluorocarbon vapor and water vapor from step (a) through a zone maintained at a temperature less than 100.degree. and at least 1.degree. C above the atmospheric pressure boiling temperature of the fluorocarbon to condense a substantial portion of the water vapor but not a substantial portion of the fluorocarbon vapor and, preferably, so that the partial pressure of the water in the remaining vapor mixture is less than about 25 cm of mercury,C.
    Type: Grant
    Filed: September 8, 1976
    Date of Patent: April 25, 1978
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Harold L. Jackson, Frederick W. Mader
  • Patent number: 3998588
    Abstract: Process for continuously transferring heat to a moving band of solid material, for example, a textile, a film, particles, or any shaped or unshaped article, the band preferably comprising a disperse dyeable synthetic polymer, for example, a polyester or polyamide, said process comprising passing the band through a substantially enclosed purging-drying region containing the superheated condensable vapor of a liquid having an atmospheric pressure boiling point of less than 120.degree. C., thence immediately thereafter through a substantially enclosed, heat-transfer region containing the superheated condensable vapor of a fluorocarbon having a fluorine to carbon atom ratio of at least 1.5, a solubility parameter of not more than 6.
    Type: Grant
    Filed: May 28, 1975
    Date of Patent: December 21, 1976
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: George R. Coraor, Harold L. Jackson, Frederick W. Mader
  • Patent number: 3991481
    Abstract: Process for substantially quantitatively removing and recovering a volatile, organic, water-immiscible wetting liquid from a solid material which is wet therewith, which process comprises intimately contacting the solid material first with the superheated vapor of a water-immiscible, organic stripping liquid and thereafter with dry steam, said contacting taking place in an environment substantially free of noncondensable gas, condensing the mixture of organic vapor and steam to form a two-phase liquid mixture consisting of liquid organic phase and liquid water phase, and separating the liquid organic phase and the liquid water phase.
    Type: Grant
    Filed: May 28, 1975
    Date of Patent: November 16, 1976
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: George R. Coraor, Harold L. Jackson, Frederick W. Mader