Abstract: A tin dust contains Sn of 37. 43%,Zn of 8. 82% and In of 0. 56%,which has a high comprehensive recovery value. The valuable metals indium and zinc were recovered by sulphuric acid-atmospheric leaching process,while tin was effectively enriched in the slag. The optimum parameters were determined by the experimental conditions as curing temperature of 140 ℃ ,curing holding time of 40 min,mass ratio of sulfuric acid to tin smoke and dust of 0. 7 ∶1,leaching time of 1. 5 h,leaching temperature of 90 ℃ ,leaching liquid-solid ratio of 4 ∶1 mL / g. Under these conditions,the average leaching rates of indium and zinc reached 96. 68% and 97. 70% respectively,and the average leaching rates of tin decrease to 0. 52%. Compared with the atmospheric acid leaching process,the leaching rate of indium and zinc can be significantly increased by sulfuric acid curing atmospheric pressure leaching process,and the leaching rate of tin can be significantly reduced,which realizes the efficient separation of indium,zinc and tin.

Key words: tin flue dust,indium,sulphuric acid curing,atmospheric leaching