Extraction of antimony from a hydrochloric acid side stream of copper electro-refining by hydrolysis
Eduardo Díaz, J.A.M. Calvo, J.M. Gallardo, A. Paúl
Abstract
This work explores the feasibility of recovering antimony, present in a side stream of hydrochloric acid resulting from a copper electro-refining process, by hydrolysis with water. A range of variables that can affect the process have been studied. According to the results, under optimal conditions (pH = 0.645 T = 34 °C), antimony extraction yield is 94.4%. The reaction product is amorphous, with antimony content close to 70% and Cl and O contents similar to the stoichiometric ratios of complex oxychloride compounds. Moreover, significant amounts of arsenic and bismuth have been revealed. The presence of bismuth affects the extraction performance, while arsenic impairs its potential commercialisation.