Patents Assigned to Freeport Research and Engineering Co.
  • Production of silica and fluorine-containing coproducts from fluosilicic acid
    Patent number: 4915705
    Abstract: A process for producing high grade silica and fluorine-containing coproducts from fluosilicic acid is described. To produce silica, the fluosilicic acid is reacted with aqueous ammonia to produce a solid silica product and a solution of ammonium fluoride. The solid silica is washed under controlled conditions and further processed to produce a high grade product. The ammonium fluoride solution is concentrated and sold as a concentrated ammonium fluoride solution product or reacted with metal hydoxides or oxides to produce metal fluorides.
    Type: Grant
    Filed: July 22, 1988
    Date of Patent: April 10, 1990
    Assignee: Freeport Research and Engineering Co.
    Inventors: Phillip D. Mollere, Tadeusz K. Wiewiorowski, Vivian C. Astley, Willis L. Thornsberry, Jr., Michael A. Murray