Abstract: The present invention is concerned with a method for selectively removing antimony and bismuth from an impure sulphuric acid solution containing at least 50 g/L of acid and some concentration of ferric ion (for example copper refinery electrolyte), is disclosed. The method involves contacting the impure solution with a sufficient quantity of finely divided metallic copper so as to prereduce all ferric ion present in the solution to the ferrous oxidation state. The prereduced solution is then contacted with a chelating resin. The method avoids the deleterious loading of ferric iron onto the ion exchange resin and prevents the return of excessive amounts of chloride ion with the purified electrolyte.