Separation of copper, nickel, tin and lead by ion exchange from plating rinsewater

Because large amounts of water are used in many surface finishing processes, it is necessary to reclaim the water by removing metallic ions that contaminate it. Statistical methods were applied to ion exchange techniques to determine the distribution coefficients of copper, nickel, tin and lead ions in various concentrations of HCl. The calculated distribution coefficients point to the dependency of the ion exchanger's selectivity and the complexed metallic ion, the share of the ion type bound, as well as ligand concentration (Cl-) ions in the solution. In-plant experiments have determined breakthrough (resin) capacities for all the indicated metallic ions and their mixtures.