Patents by Inventor Harold F. Porter

Harold F. Porter 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).

  • Production of sodium perborate crystals having improved abrasion resistance
    Patent number: 5215730
    Abstract: A method for improving abrasion resistance of sodium perborate tetrahydrate crystals prepared by reacting sodium metaborate with hydrogen peroxide in an aqueous slurry crystal growth medium, the improvement including highly supersaturating the aqueous slurry crystal growth medium. Also, an agent such as an excess of caustic may be added to the aqueous crystal growth medium to limit the growth rate of individual crystals.
    Type: Grant
    Filed: October 29, 1991
    Date of Patent: June 1, 1993
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Janet M. Rogers, Linda F. Tolbert, Harold F. Porter, deceased, Daniel A. Green
  • Process for shipment of sodium cyanide slurries
    Patent number: 4902301
    Abstract: A process for manufacturing, shipping and unloading substantially solid, ice-like sodium cyanide dihydrate containing essentially no liquid water. A slurry of 58 weight percent or higher sodium cyanide is rapidly cooled to the anhydrous/dihydrate transition temperature while minimizing the settling out of sodium cyanide crystals to form the product in a container. Dissolution prior to unloading is by adding heat and water or dilute sodium cyanide solution.
    Type: Grant
    Filed: April 25, 1988
    Date of Patent: February 20, 1990
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Janet M. Rogers, Harold F. Porter
  • Process for production of sodium cyanide
    Patent number: 4847062
    Abstract: A process for producing anhydrous sodium cyanide crystals by absorbing hydrogen cyanide synthesis gas that contains oxides of carbon and water in aqueous sodium hydroxide and crystallizing the sodium cyanide solution that results from the absorption. The sodium carbonate that forms in the absorption is not removed prior to crystallization.
    Type: Grant
    Filed: September 24, 1987
    Date of Patent: July 11, 1989
    Assignee: E. I. Du Pont De Nemours and Company
    Inventors: Janet M. Rogers, Harold F. Porter
  • Process for purifying hexamethylenediamine
    Patent number: 4282381
    Abstract: Hexamethylenediamine (HMD) is purified by dissolving ammonia in crude molten HMD under pressure, directing the solution thus prepared to a reduced pressure zone where the ammonia is vaporized thereby causing a portion of the HMD to crystallize following which the crystals in the slurry are washed with essentially pure HMD. This purified HMD is suitable for conversion into polyamide fibers.
    Type: Grant
    Filed: August 21, 1980
    Date of Patent: August 4, 1981
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Oscar R. Buehler, Harold F. Porter