EXTRACTION PHOSPHORIC ACID PURIFICATION PROCESS

摘要

FIELD: inorganic compounds technology. SUBSTANCE: invention relates to removal of sulfates and suspended materials from concentrated solutions (57.5-64% P2O5) of extraction phosphoric acid obtained via acid decomposition of apatite concentrate. In particular, to extraction phosphoric acid containing 57.5-64% P2O5 and 0.3-3% SO4, strontium compound is added in amount required to achieve ratio Sr2+: SO2-4 = 0.82-1.05 in acid. Stirring is effected for 0.5-1 h followed by settling for 50-100 h and separation of concentrates product sediment. EFFECT: enabled purification of high-concentration phosphoric acid and essentially full removal of sulfate precipitates. 2 cl, 3 ex