The use of electrohydrolysis for the recovery of sulphuric acid from copper-containing solutions

Two lab-scale electrohydrolysis (EH) cells have been used to study the effectiveness of this method in the recovery of sulphuric acid from copper-containing electrolytes such as those present in copper electrorefining. Results for the effect of cell current density and temperature on the processing of synthetic electrolytes have been obtained. It has also been shown that EH is effective in recovering sulphuric acid from an industrial electrolyte. In a six-compartment EH cell, a recovered acid concentration of 50 g/L can be obtained in 12 h operation at 45 degrees C and a cell current density of 225 A/m(2) with a cell voltage of 5.9-6.5 V. An equivalent sulphuric acid concentration, with a 30% reduction in cell voltage, can be obtained in similar conditions using a simpler, three-compartment design. (C) 2005 Elsevier B.V. All rights reserved.