Chemistry of sulfate chloride perhydrates. Part 2.—Reperhydration by H2O2
Abstract
The perhydrate, 4Na2SO4 NaCl2H2O2 , has been heated in order to fully desorb the H2O2 . The resulting powder [an intimate mixture of Na2SO4(III) and NaCl] was exposed to the vapour above a solution of H2O2 . Two mechanisms are observed for the regeneration of the perhydrate: at high concentrations of H2O2 (>0.60 g cm–3), direct reaction between the powder and the gaseous H2O2 occurs; at concentrations <0.60 g cm–3 , the powder becomes wet and the Na2SO4 phase (III) transforms into phase (V). Regeneration into the perhydrate then proceeds by crystallisation of the perhydrate from the slurry of Na2SO4(V) and NaCl. The two mechanisms occur together at intermediate concentrations of H2O2.