METHOD OF SO-INTO-SO CONVERSION CATALYST Russian patent published in 1999 - IPC

FIELD: oxidation catalysts. SUBSTANCE: solutions of active components containing oxides of vanadium and alkali metals (K, Na, Cs, Rb) are mixed with synthetic silica and mixture is then thermally treated and molded. Silica is prepared by precipitation from liquid glass with sulfuric acid solution in two steps. First, silicon dioxide concentration before sulfuric acid is poured in is maintained between 50 and 160 g/l while pH is changed from 12.5-10.5 to 4.0-8.5. Then liquid glass is added to make silicon dioxide concentration and pH value jump to 170-270 g/l and 12.0-9.0, respectively, after which sulfuric acid is added to achieve pH 4.0-8.5. EFFECT: improved apparent density and mechanical strength of catalyst. 2 cl, 1 tbl, 9 ex