Production of copper from minerals through controlled and sustainable electrochemistry

Abstract

Extraction of copper using halide media is more rapid than in sulfate media, and the resulting cuprous ions require less energy to electrowin than cupric ions from sulfate media. The quality of the deposit is influenced strongly by the deposit roughness, which is controlled by mass transport. Thus, coupled halide leaching of chalcopyrite and subsequent electrowinning with controlled mass transport provide an opportunity for more sustainable copper production. This paper presents new insights regarding copper extraction and recovery methods from chalcopyrite ore in aqueous chloride media using leaching and electrowinning as well as steps for deposit quality improvements. Viability of integrated leaching and electrowinning was examined using low grade copper ore and continuous leaching solution recirculation. Other sets of experiments were conducted where leaching and electrowinning were performed separately, in order to find optimum experimental conditions for coupled leaching and electrowinning. Analysis based on scientific and statistical tools are presented for comparative evaluation. Copper electrodeposit morphology improvement by use of a variety of smoothing additives as well as mass transport control was also evaluated.