Study On The Separation Behavior Of High Arsenic And Antimony Fumes In Sulfur And Oxygen Systems

Massive dust with high content of arsenic and antimony are generated from nonferrous pyrometallurgical industries,and the contents of As and Sb are more than20%.The dust not only represents potential hazard to the environment but also is a secondary resource.The dust can not be directly recycled to the antimony smelting process,due to the high arsenic content.It is necessary to treat the dust individually to remove arsenic and recover the antimony resource.The dust with high content of arsenic and antimony used in this study was provided by a plant which treated tin anode slime through a pyrometallurgical process.Based on the volatility difference of sulfide and oxide of arsenic and antimony,the As and Sb behaves separated were researched in the selective sulfuration process and oxidation fixation process.In the process of sulfuration,the volatilization rate of arsenic is about 95.36%and that for antimony is only about 9.07%under the condition of roasting temperature of 350℃,sulfur amount of 22%,roasting time of 90 min and nitrogen flow rate of 70 mL/min.The roasted residue,as antimony sulfide ore,is used for antimony produced.In the process of oxidation fixation,the volatilization rates of As and Sb can reach up to90.53%and only 13.20%,respectively at a roasting temperature of 450℃,an Fe₂O₃dosage of 15%,roasting time of 90 min,and O₂ content of 21 vol%.Besides,the roasted product is reducing by LDPE achieving the reduction and recovery of Sb phases.The volatilization rates of Sb can reach up to 93.50%and lead is not volitale,and susceptibility of iron is 99.50%,at a roasting temperature of 1000℃,LDPE dosage of 25%,roasting time of 60 min.Because arsenic and antimony possess similar character,the solid solutions and amorphous substance are formed under different conditions,which will hinders the separation of As and Sb.The purpose of two methods destroys or hinders the solid solutions and amorphous substance,and further achieves the separation of As and Sb.These methods provide some new ideas;it has some significance for resolving contradiction between resource shortage and environmental protection.