Electrochemical codeposition of arsenic from acidic copper sulfate baths: The implications for sustainable copper electrometallurgy

•The main source of arsenic contamination is codeposition during the nucleation stage.•Convection and concentrated Cu(II) electrolytes mitigate arsenic contamination.•The reduction of As(III) to metallic As does not occur readily.•Fast removal of As(III) possible by copper-arsenic codeposition.