Regeneration of Chromium Electroplating Electrolytes by the Application of Electromembrane Processes

Abstract

The use of the electromembrane method for the purification of chromium plating electrolytes from cationic impurities (iron, copper, etc.) by three approaches are described. The first variant is based on the removal of these ions during their migration from the solution to be purified into a catholyte through a cationexchange membrane. The second variant is a transfer of chromate anions from a contaminated solution into the anolyte through an anion-exchange membrane. In the third method for the recuperation of chromic acid, accumulated in a recovery bath, it is proposed to use the immersed electrochemical module, combining the processes of concentration and purification from impurities, instead of evaporation.