Study On Separation Of Arsenic And Antimony From Flue Dusts With High Content Of Arsenic And Antimony

In smelting process, arsenic in raw materials is mainly enriched in all kinds of flue dusts due to the volatilities of arsenic and its compounds. These high arsenic flue dusts also contain a number of other valuable metals. Removing arsenic and recovering valuable metals from these flue dusts is an effective way of eliminating arsenic pollution and improving resource utilization.In pyrometallurgical processing anode slime of lead electrolytic refining, a kind of flue dust with high content of arsenic and antimony is produced and up to date, there is not an appropriate technique to process it, resulting in resource waste and environmental pollution. Aiming at this situation, the studies on the atmospheric pressure water leaching, atmospheric pressure caustic alkali leaching and oxygen pressure caustic alkali leaching of the flue dusts with high content of arsenic and antimony, as well as on the treatment of alkaline solution containing arsenic, were carried out in order to remove arsenic from antimony and lead in the flue dusts. The main conclusions obtained in the study were as follows.In the atmospheric pressure water leach of removing arsenic, the leach efficiencies of arsenic and antimony were31.26%and0.46%respectively under the optimum condition of temperature60℃, time2hours and liquid to solid mass ration10, demonstrating that arsenic can not be separated from antimony completely in water leach process.In the atmospheric pressure caustic leach of removing arsenic, the leach efficiencies of arsenic and antimony were74.27%and1.51%spectively under the optimum condition of NaOH concentration25g/L temperature60℃, time2hours and liquid to solid mass ration10. Compared with water leach, the efficiency of removing arsenic increases obviously, but a complete separation of arsenic from antimony still has not reached.In the oxygen pressure caustic alkali leach, under the optimum condition of NaOH concentration40g/L, oxygen pressure2.0MPa, temperature140℃, time2hours and liquid to solid mass ratio10, the leach efficiency of arsenic was above95%, while the leach efficiencies of both antimony and lead were less than1%, indicating that a complete separation of arsenic from antimony was obtained. XRD analyses showed that antimony and lead were present in the phases of NaSb(OH)6, Sb2O3·2Sb2O5, Pb2Sb207in the leach residues. There are28figures,10tables,75references in this paper.