含砷烟尘的综合利用

采用氢氧化钠碱性浸出分离回收含砷烟尘中的砷,在优化试验条件下,砷、锑、铅的浸出率分别为99.27%、1.83%和0.20%;砷浸出液经氧化—冷却结晶回收砷酸钠后返回浸出过程循环利用,整个脱砷工艺闭路循环。采用硫化钠浸出—空气氧化法分离回收含砷烟尘碱浸渣中的锑并制备焦锑酸钠,碱浸渣中锑的浸出率为93.03%,锑浸出液中锑沉淀率为98.51%。采用硫酸浸出—铝板置换分离回收硫化钠浸出渣中的铟并制备海绵铟,铟的浸出率为71.83%。硫酸浸出渣中铅的主要以PbS的形式存在,可以作为铅冶炼的原料返回铅厂回收铅。

Comprehensive Utilization of Arsenic Bearing Dust

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.