An efficient and clean method for the selective separation of arsenic from scrap copper anode slime containing high arsenic and tin

As the different properties of conventional copper anode slime and scrap copper anode slime (SCAS), the disposal of arsenic before the extraction process is very important. There was simultaneous leaching of As and Sn when the hydrometallurgical process or the sulfation roasting-leaching was applied to treat arsenic in the SCAS. It was difficult to achieve the effective separation of arsenic and tin by these methods. Therefore, an effective and clean pretreatment method for selectively separating arsenic from scrap copper anode slime containing high arsenic and tin via oxygen-enriched roasting followed by acid leaching was proposed. The volatilization rate of arsenic was only 1.13% under the optimum oxygen-enriched roasting parameters. The results of acid leaching showed that the leaching efficiencies of Cu and As were above 97%, and the elements of Sn, Pb, and Ag were enriched in the leaching residue. It is a promising method which can not only obtain selective leachable compounds (such as insoluble SnO2) but also restrict the volatilization of arsenic by forming (MeO)x(As2O5)y or As2O5 to solve the problem of easy dispersion of arsenic, both of which were good for sulfuric acid leaching. Meanwhile, there was no need to develop a new process for treating the leachate, which can be directly sent to the electrolyte purification process.

Automated summary

An effective method for selectively separating arsenic from scrap copper anode slime using oxygen-enriched roasting and acid leaching has been proposed. This method restricts the volatilization of arsenic and allows for the extraction of selective leachable compounds.