ZINC OXIDE PRODUCTION PROCESS Russian patent published in 2003 - IPC

FIELD: inorganic compounds technology. SUBSTANCE: method involves preparing zinc oxalate crystalline hydrate from zinc acetate and oxalic acid. Crystalline hydrate is treated with ammonium oxalate aqueous solution at temperature not exceeding 150 C during 1-2 h and then dispersed in organic solvent mixture, in particular in ethanol/diethoxyethane/1,3-dioxolane 1:1:1 mixture, whereupon air flow at temperature no higher than 90 C is passed through resulting dispersion to form precipitate. The latter is purged with air flow at temperature no higher than 120 C and then crystallization water is removed by passing air or nitrogen flow at temperature no higher than 270 C followed by thermal decomposition of anhydrous salt in oxygen flow at 300-450 C. Zinc acetate can also be obtained from waste isotope-rich zinc-containing material, in particular zinc oxide-containing waste. To this end, indicated waste is treated with acetic acid solution. Method makes it possible to obtain high-purity zinc oxide with good spreading capacity, aggregation and sedimentation resistance in liquid media, and showing low powder agglomeration. EFFECT: improved quality of zinc oxide product and enabled recovery of the same-quality product from zinc oxide-containing waste. 3 cl, 1 tbl, 3 ex