Home – Home – Jornals – Chemistry for Sustainable Development 2008 number 4

The possibility of phosphogypsum processing into sodium sulphate and technical-grade calcium carbonate using soda is considered. It is shown that the conversion of phosphogypsum proceeds within 20-30 min by 96-98 %. To obtain sodium sulphate solutions with low concentration of calcium sulphate, it is necessary to carry out conversion under the conditions of a 5-10 % excess of soda over sulphate ions with respect to the stoichiometrically necessary amount. It is established that in this case sodium sulphate corresponds to the high-grade product. The second product of phosphogypsum processing - technical-grade calcium carbonate - is promising for use as filler in the production of linoleum; after further processing it is a raw material for obtaining the salts of calcium, strontium and rare earth elements.