Processing of electroplating effluent for the recovery of zinc and chromium using ion exchange technique

Abstract

In order to reduce the pollution and conserve the resourc-es, a process has been proposed to recover zinc and chrom-ium from the electroplating effluent following ion exchange technique. The studies for the extraction of zinc in diffe-rent contact time, pH of the solution, resin dose, mechani-sm of adsorption etc. were made for the recovery of zinc from the solution using cationic resin,Lewatit VP OC 1026. The resin, Lewatit VP OC 1026 has been found to be select-ive for the extraction of zinc from the effluent leaving total chromium in the raffinate. The zinc was effectively eluted from loaded resin with dilute sulphuric acid. The mechanism of extraction of zinc was found to follow the Langmuir isotherm. The chromium was extracted from the raffinate using anionic resin, Amberlite IRA 400 Cl and loaded chromium eluted effectively with 20% NaOH.