PROCESS FOR RECOVERING BASIC ZINC CARBONATE WITH HIGH PURITY

摘要

A process for recovering basic zinc carbonate with high purity is provided to obtain a basic carbonate with a high purity which hardly contains an iron component, and obtain a final target material at a low temperature as compared with a conventional method by applying a small amount of sodium carbonate or sodium hydroxide when forming ammonia. A process for recovering a basic zinc carbonate comprises: dissolving zinc sulfate in which iron sulfate is present into water; applying a zinc powder to the zinc sulfate solution; filtering the mixed solution to obtain a filtrate; adding carbonate to the filtrate to form a precipitate; recovering the formed precipitate; adding ammonia water to the precipitate to obtain a zinc carbonate-ammonia complex in a liquid phase; filtering the zinc carbonate-ammonia complex to obtain a filtrate; adding sodium carbonate or sodium hydroxide to the filtrate; and pyrolyzing the mixture to precipitate a basic zinc carbonate. The zinc powder is added in the amount of 1 to 5 weight parts based on the total weight of iron sulfate and zinc sulfate. The sodium carbonate or sodium hydroxide is added to the filtrate in the amount of 1 to 5 weight parts with respect to 100 weight parts of the filtrate before pyrolyzing the mixture. The pyrolysis is performed at a temperature of less than 100 deg.C.