METHOD OF PREPARING SORBENT Russian patent published in 1997 - IPC

FIELD: inorganic sorbents. SUBSTANCE: invention relates to preparing sorbents that can be used in hydrometallurgy of nonferrous and rare metals as well as in treatment of waste water from corresponding plants, in particular, to preparing oxyhydrate sorbents. Method includes precipitation of metal oxyhydrate in the form of hydrogel by way of interaction of metal salt with alkali in presence of organic substance followed by incubation, filtration, drying, and granulation of final product. Alkali reacts with water-soluble ferric salt. Reaction of initial substances is carried out in weakly alkaline medium, whereupon potassium bichromate is added in chromium to iron molar ratio (0.01- 0.07):1, and, after addition of nitrilemethylphosphonic acid, pH value is adjusted to 3.5-4.5 with subsequent washing off potassium bichromate with ammonia solution. EFFECT: improved preparation procedure and enlarged choice of sorbents. 1 tbl