laboratory study of the effects of process parameters on the performance of weak black liquor (WBL) electrolysis cells showed that anode material, current density and temperature are critical to the operation. The two latter variables showed an interaction effect upon the operation of the cell. In terms of energy efficiency, the IrO2 anode performed better than the Pt anode. The addition of sodium sulfate to the WBL was beneficial to the energy efficiency. No chlorine gas was produced when electrolyzing WBL containing sodium chloride within the pH range 5.4 to 13.