Removal of sulfuroxyanions by magnesium aluminium oxides and their thermal decomposition

Abstract
The behaviour of the removal of the sulfuroxyanions, SO2−4, S2O2−3, S2O2−6 and S4O2−6, in aqueous solutions by Mg0.61Al0.260.13O (□:vacancy) was investigated at 40–80°C. All the sulfuroxyanions were removed from solution competitively with OH to form the hydrotalcite‐like compounds. The rate of the removal was first order with respect to the concentration of the sulfuroxyanion in the solution, and the apparent activation energy was about 60 kJ mol−1. All the sulfuroxyanions intercalated in the interlayer of hydrotalcite structure decomposed to SO2−4 at 100–300°C.