method for catalytic oxidation of calciumsulfit

摘要

The catalytic oxidations of CaSO3 with air or O2 is carried out hydrothermally or in a soln. of CaCl2 with pref. Fe(II) or (Fe(III) sulphates or sulphates of Co, Cu, Zn, Mn or Ce present at a temp. at which the oxidn. prod. is CaSo4 semi-hydrate or the soluble anhydride. When Ce sulphates are used as catalysts, persulphate ions must also be present. The present is economical and is quicker than oxidation with air/O2 alone, and gives better yields than other catalytic methods. Dismutation into sulphur does not occur.