Removal of Zn2+ and Cr6+From Waste Water Samples, Using Natural Iranian (Aftar) Zeolites

Abstract

This paper concerned the removal of Zn2+ and Cr6+ ions from waste water using a naturally 
occurring zeolite from semnan region in Iran. A continuous fixed-column study was carried out by using 
zeolite as a low-cost adsorbent for the removal of Zn2+ and Cr6+ ions from aqueous solution under the effect 
of various process parameters such as, grain size and time. The efficiency of removal was higher for Zn than 
Cr ions. The Zn2+ and Cr6+ ions uptake by zeolite increased with initial ions concentration and column 
height, but decreased as the flow rate increased. The adsorption capacity reached a maximum at grain size of 
0.71mm