Process for preparing hydrogen fluoride
    13.
    发明授权
    Process for preparing hydrogen fluoride 失效
    制备氟化氢的方法

    公开(公告)号:US5219551A

    公开(公告)日:1993-06-15

    申请号:US707611

    申请日:1991-05-30

    IPC分类号: C01B7/19

    CPC分类号: C01B7/192

    摘要: A process for preparing hydrogen fluoride, which comprises (i) reacting calcium fluoride with sulfuric acid to produce a gypsum and a gas containing hydrogen fluoride, (ii) separating hydrogen fluoride from said gas containing hydrogen fluoride, (iii) absorbing said hydrogen fluoride-separated gas with water to obtain an aqueous solution containing hydrogen fluoride and silicofluoric acid, (iv) reacting calcium carbonate with said aqueous solution to obtain a suspension containing silicic acid and calcium fluoride, (v) adding an alkaline substance to said suspension to make pH at least 8, thereby stabilizing the silicic acid as a colloidal solution, (vi) separating a calcium fluoride solid and the colloidal solution of silicic acid from said suspension, and (vii) recycling the separated calcium fluoride as a starting calcium fluoride.