Patent ID: 9567217
Date: 2017-02-14
CPC Classifications: C01B,Y02E

Claim:
1. A method for producing a difluorophosphate, comprising: a step of reacting an aqueous hydrofluoric acid solution with an oxyhalide of phosphorous (except phosphoric trifluoride) to produce a crude difluorophosphoric acid, a step of reacting the crude difluorophosphoric acid with a halide of an alkali metal, an alkaline earth metal, aluminum or an onium to produce a difluorophosphate in the crude difluorophosphoric acid, and a step of heating and drying the crude difluorophosphoric acid containing the difluorophosphate to distill away the crude difluorophosphoric acid, or a step of precipitating the difluorophosphate in the crude difluorophosphoric acid by crystallization, subsequently separating the difluorophosphate by solid-liquid separation, and further distilling away the crude difluorophosphoric acid contained in the difluorophosphate after the solid-liquid separation.