The influence of high energy milling to the adsorption of Cd(II) and Zn(II) ions on activated zeolite

Abstract

Natural zeolite is believed to be able to effectively reduce heavy metal levels in water. However, due to the weakness of natural zeolites which have a low surface area and impurity so that the adsorption ability of heavy metals becomes less optimal. Increasing the surface area by using high energy milling is expected to optimize the ability of adsorption. In this study, the particle size of natural zeolite was reduced by using high energy milling then activated with HCl and NH₄Cl. The adsorption process was carried out by mixing activated zeolite and activated zeolite milling(activated zeolite fine powder) in a solution of metal ions Zn(II) and Cd(II). SEM-EDX analysis showed a change in surface morphology size on activated zeolite milling and GSA indicated an increase in surface area from 69.48 m²/g to 97.9 m²/g. Activated zeolite tends to having a little bigger in ability of adsorption to Cd(II) ions and Zn (II) ions than activated zeolite milling in highest variation of concentration, 800 ppm. In optimum contact time of adsorption, activated zeolite could adsorp Cd(II) ions shorter nevertheless longer to Zn(II) ions than activated zeolite milling. Both of the zeolites have ability to adsorp Zn(II) ions more than Cd(II) ions.