PROCESS FOR TREATING SMOKE-FREE POWDER WASTE Russian patent published in 1997 - IPC

FIELD: paint industry, more particularly domestic chemistry products. SUBSTANCE: smoke-free powder waste is subjected to mechanical grinding in aqueous, medium. It is then subjected to autoclave depolymerization in aqueous 0.5-1.5% solution of nitric acid or in admixture with sulfuric acid at 120-140 C. The whole is washed till the mixture becomes neutral. Depolymerization is carried out till viscosity of solution in acetone is 1-3 Engler. EFFECT: more efficient treatment process. 2 cl, 2 tbl