A comparison of various ion exchange resins for the removal of ferric ions from copper electrowinning electrolyte solutions part I: Electrolytes containing no other impurities

Column testing was performed on four commercially available ion exchange resins to evaluate their ability to remove ferric from a synthetic copper electrowinning electrolyte. Results from the loading test indicated that the sulphonated diphosphonic resin, Eichrom Diphonix, has significantly lower capacity than other resins tested. Stripping tests were performed using cuprous elution and showed that the aminophosphonic resin, LanXess Lewatit TP260, stripped more slowly than the two sulphonated monophosphonic resins, Purolite S957 and generic resin D416. Results from the various stripping tests indicate that the use of an ORP titration on the elution cycle appears to be an excellent indicator of the elution endpoint. Further stripping tests performed on the Purolite S957 resin indicate that total stripping time was approximately linear with the theoretical concentration of cuprous in solution, for theoretical cuprous concentrations between 0.4 and 0.8 g/L Cu+.