Adsorption of Copper(II) and Zinc(II) ions by various agricultural by-products. Experimental studies and modelling

Effective removal of heavy metals from aqueous solutions belongs to the most important issues for many industrialized countries. Removal of copper(II) and zinc(II) ions from leaching solution of industrial waste were studied using hazelnut, almond and walnut shells. Batch adsorption experiments were performed in function of pH, contact time and adsorbent dosage. Adsorption kinetics was investigated using the pseudo-first and pseudo-second order, Elovich equations and intraparticle diffusion models. The results indicate that the second order model best describes adsorption kinetic data and the agricultural by products investigated may be used for removal of copper(II) and zinc(II) ions from leaching solution of industrial waste.