SODIUM PERCARBONATE PRODUCTION PROCESS Russian patent published in 2001 - IPC

FIELD: inorganic compounds technology. SUBSTANCE: soda monohydrate with bulk density below 0.55 g/l is brought into interaction with quasi-stoichiometric amount of 50-70% hydrogen peroxide solution. Reaction is carried out at 20-80 C and vigorous stirring. Paste-like wet sodium percarbonate is dried, after which up to 1 wt.% of alkali and/or alkali-earth metal stearate can be added. Material is compacted at pressure 50- 150 bar to form ceramic product. The latter is crushed and screened to give granulate. Level of active oxygen in sodium percarbonate granulate is 14.5-15.2 wt.%, bulk density 0.8501.1 kg/l, average grain diameter 550-1100 mcm, dissolution rate at least 95% after 1 min and at least 99% after 2 min, exothermic peak within 159-162 C, loss of stability below 6.2% when measured at 105 C - 2 h, and coefficient of abrasion no higher than 8%. Bleaching and detergent compositions contain from 0.5 to 40 wt.% of sodium percarbonate, the rest being modifying additives, enzymatic stabilizers, pollution-removal substances, soap foam regulators, optic bleachers, opacity-imparting substances, corrosion inhibitors, antistatic agents, and bactericidal substances. EFFECT: enhanced preparation process efficiency. 28 cl, 5 tbl, 4 ex