Patents Assigned to Phosphate Engineering and Construction Co.
  • Process for the production of phosphoric acid and hydrogen fluoride from phosphate rock and fluosilicic acid
    Patent number: 5427757
    Abstract: Fluosilicic acid is reacted with phosphate rock in order to produce wet process phosphoric acid and calcium fluoride which is later reacted with sulfuric acid to produce hydrogen fluoride and calcium sulfate. The hydrogen fluoride is then stripped from the phosphoric acid and recovered as either anhydrous hydrogen fluoride or concentrated hydrofluoric acid or reacted with aluminum trihydrate to produce aluminum fluoride; with sodium carbonate to produce sodium fluoride/bifluoride; or with ammonia to produce ammonium fluoride/bifluoride.
    Type: Grant
    Filed: December 2, 1993
    Date of Patent: June 27, 1995
    Assignee: Phosphate Engineering and Construction Co.
    Inventors: William R. Erickson, Leif E. Bouffard