| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method and an apparatus for separation, with which hydrofluoric acid and ammonium hydrogen fluoride are respectively separated from a mixed acid at least including hydrofluoric acid, ammonium hydrogen fluoride, ammonium silicofluoride, and water. <P>SOLUTION: The method for separation includes: a first distillation step to recover a distillate 200 including hydrofluoric acid and water and to recover a bottom 500 including ammonium hydrogen fluoride and silicon by distilling the mixed acid 100; a second distillation step to separate mainly water from the distillate 200 by distilling the distillate 200 and recover a bottom 600 with a hydrofluoric acid concentration higher than that in the distillate 200; and a deposition step to make a first solid 510 crystallized from the bottom 500 of the first distillation step and ammonia react with each other. <P>COPYRIGHT: (C)2013,JPO&INPIT |
