A novel process for the regeneration and purification of spent electrolyte from sodium hydroxide zinc metallurgy to reduce sodium hydroxide consumption is reported in this paper. This is achieved through a method of causticisation, which maintains the quality of zinc metal powder. This process consists of two steps: sodium carbonate separation and causticisation. The sodium carbonate in the spent electrolyte is separated by adding solid NaOH to increase the alkaline concentration to over 350 g/L. The delamination of the solid-liquid phase appears after the above mixture stands for a few hours....
