Patents Assigned to HF Extraction, LLC
  • Phosphate acidulation utilizing HF acid
    Patent number: 6676914
    Abstract: Phosphoric acid, essentially free from impurities, is prepared by reacting aqueous hydrofluoric acid with phosphate in particles of calcium bearing phosphate rock to form a calcium fluoride pseudomorph solid from which filter-grade phosphoric acid is separated. By reacting the pseudomorph solid with sulfuric acid and thermally treating the reaction product, the HF can be liberated and recycled back to the reaction step of the process. All of the impurities from the phosphate rock are contained in the resulting CaSO4.
    Type: Grant
    Filed: June 9, 2000
    Date of Patent: January 13, 2004
    Assignee: HF Extraction, LLC
    Inventors: Samuel Franklin Sweat, Claude E. Breed, Kenneth E. McGill
  • Preparation of calcium silicate and sulfur dioxide
    Patent number: 6395246
    Abstract: Nascent hydrogen and nascent oxygen are used to convert calcium sulfate and silicon dioxide to calcium silicate and sulfur dioxide.
    Type: Grant
    Filed: October 18, 2000
    Date of Patent: May 28, 2002
    Assignee: HF Extraction, LLC
    Inventors: Samuel Franklin Sweat, Claude E. Breed, Kenneth E. McGill