Abstract:Arsenic was separated from arsenic bearing dust with sodium hydroxide solution. Leaching rate of arsenic, antimony and lead is 99.27%, 1.83% and 0.02%, respectively under the optimal conditions. Alkaline solution recovered from sodium arsenate by oxidation and cooling-crystallization is recycled to leaching process to realize water closed circuit. Product of sodium pyroantimonate is prepared by sodium sulfide leaching and air oxidation from alkali leaching residue. Under the optimal conditions, antimony leaching rate is 93.03% and antimony precipitation rate is 98.51%. Product of sponge indium is prepared by sulphuric acid leaching and aluminum plate replacement from sodium sulfide leaching residue with indium leaching rate of 71.83% under the optimal conditions. Main component of sulfuric acid leaching residue is lead sulfide, which can return to lead pydrometallurgy process.