Effect of Chemical Conditioning and Operational Parameters on Cadmium Adsorption by Zeolite

Zeolites are used for the adsorption of heavy metals. Modification of natural zeolites with various reagent increases their adsorption capacity. In this regard, NaCl, and NH4Cl were used to modify this type of adsorbent.  In this study, the effects of chemical conditioning and particle size on cadmium adsorption, using zeolite followed by statistical evaluation of parameters affecting the cadmium adsorption process were investigated. According to the results, zeolite treated by NaCl had the highest adsorption capacity among the zeolite modified by NH4Cl and natural zeolite. Also, the result showed that an increase in particle size of adsorbent enhanced the adsorption efficiency. Finally, the effect of various parameters such as time, temperature, and pH on cadmium adsorption was investigated. As a result, with respect to the effect of various parameters on cadmium adsorption using Na-zeolite, the following trend was observed: pH>metal concentration>temperature> time.