Study upon the recuperative purging of nickel and cobalt ions from residual solutions by means of chemical precipitation

Abstract

The study introduces a cleaning method of waste waters with nickel and cobalt ions content, by the precipitation of these ions as oxalates. The aim of the study is to establish the optimum conditions for a high degree of a metal recovery like nickel oxalate or cobalt oxalate, due to the low value of their products of solubility. The parameters studied were: pH, excess of reactant reagents, concentration of ions and temperature. The crystalline form of the obtained products corresponds to: NiC2O4·2H 2O and CoC2O4·2H2O and extraction degree of metals was around 99%.