METHOD OF MAGNESIUM SULFATE PRODUCING Russian patent published in 1997 - IPC

FIELD: chemical technology, inorganic chemistry. SUBSTANCE: etching sulfuric acid solution containing 3-10 wt.-% of $$$, 10-20 wt.-% of iron sulfate, impurities of Cr, Ni and other metals is neutralized with the waste finely dispersed magnesite dust taken at ratio = (1.05-1.2):1 to sulfate ions in etching solution, at 60-80 C for 1.5-2.0 h depending on etching solution composition and the end products purpose (relative to "pure" magnesium sulfate with impurities of iron, chrome, nickel compounds and others). Before hydrothermal treatment concentration of sulfate ions is increased by addition of sulfuric acid to 22-26%. EFFECT: decreased energy consumption, simplified technology. 3 cl