Patents by Inventor Taizo Kajitani

Taizo Kajitani 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).

  • Process for producing purified monoammonium phosphate from wet process phosphoric acid
    Patent number: 4610853
    Abstract: A process for producing purified monoammonium phosphate (abbreviated to MAP) directly from wet process phosphoric acid with a high yield is provided, which process comprises reacting wet process phosphoric acid with NH.sub.3 at 50.degree..about.80.degree. C. while keeping the molar ratio of NH.sub.3 /H.sub.3 PO.sub.4 at 0.9.about.1.35; separating the resulting slurry containing MAP crystals and an insoluble sludge into a slurry containing the former and a slurry containing the latter; treating the former slurry in a conventional manner to recover MAP; while treating the latter slurry by heating it to 60.degree..about.95.degree. C. to dissolve MAP contained therein, removing the sludge by centrifugal separation and concentrating the filtrate to recover MAP; and combining the two portions of MAP.
    Type: Grant
    Filed: March 8, 1985
    Date of Patent: September 9, 1986
    Assignee: Chisso Corporation
    Inventors: Taizo Kajitani, Shigeo Fujii, Tadao Sato, Ikuo Yonehara, Chikashi Fukumura, Kenji Harita
  • Process for producing purified diammonium phosphate from wet process phosphoric acid
    Patent number: 4610862
    Abstract: A process for producing purified diammonium phosphate (abbreviated to DAP) directly from wet process phosphoric acid with a high yield is provided, which process comprises reacting wet process phosphoric acid with NH.sub.3 at 50.degree..about.80.degree. C. while keeping the molar ratio of NH.sub.3 /H.sub.3 PO.sub.4 at 1.65-1.90; separating the resulting slurry containing DAP crystals and an insoluble sludge into a slurry containing the former and a slurry containing the latter; treating the former slurry in a conventional manner to recover DAP; while treating the latter slurry by heating it to 60.degree..about.95.degree. C. to dissolve DAP contained therein, removing the sludge by centrifugal separation and concentrating the filtrate to recover DAP; and combining the two portions of DAP.
    Type: Grant
    Filed: March 11, 1985
    Date of Patent: September 9, 1986
    Assignee: Chisso Corporation
    Inventors: Taizo Kajitani, Shigeo Fujii, Tadao Sato, Ikuo Yonehara, Chikashi Fukumura, Kenji Harita