METHOD OF PROCESSING PHOSPHATE STOCK INTO PHOSPHORIC ACID AND ITS SALTS Russian patent published in 2002 - IPC

FIELD: inorganic compounds technology. SUBSTANCE: phosphate stock comes into contact with pulped cationite at weight ratio phosphate/cationite/solution equal to 1:(3-10):(1-6). Phosphoric acid solution is poured off, cake separated from cationite, and the latter is regenerated by weak hydrochloric acid solution. Decomposition process is repeated until saturated phosphoric acid solution is obtained and salts isolated. Phosphate-to-cationite ratio in each decomposition stage is chosen in correspondence with volume capacity of cationite and such as to ensure liquid-to-solids ratio (5.0-0.5):1. All types of cationites can be used. EFFECT: enabled reuse of spent cationite- regeneration solutions. 5 tbl, 23 ex