摘要
Copper dust with high arsenic content is a hazardous waste that should be treated properly.Herein,the copper dust is oxidized,leached,and separated at room temperature and atmospheric pressure.To separate As and Bi,part of As(Ⅲ)in copper dust is oxidized to As(V),so that most of the As,Cu,and Zn elements enter the solution and the Bi remains in the leaching residue.Also,the influence of several factors,such as H_(2)SO_(4) dosage,H_(2)O_(2) dosage,liquid-solid ratio,leaching temperature and leaching time,on the leaching percentage of As,Bi,Cu,and Zn is systematically investigated.The optimal conditions are obtained as follows:liquid-solid ratio of 3:1,H_(2)O_(2) dosage of 10 ml/50 g(dust),H_(2)SO_(4) dosage of 4.5 ml/50 g(dust),leaching temperature of 85 C,and leaching time of 3 h.Under these conditions,the leaching percentage of As,Cu,Zn,and Bi is found to be 97.39%,96.11%,97.32%,and 2.40%,respectively.For further recovery of As from the leaching solution,the one-step recycle leaching of the leaching solution is performed to increase the concentration of As in the recycled leaching solution.The concentration of arsenic in the recycling leaching solution is found to be 79.63 g·L^(-1),which is beneficial for the study on further recovery of As_(2)O_(3).
基金
This work was financially supported by the Fundamental Research Funds for the Central South University. Postdoctoral Research Foundation of Central South University (140050037).
