Characterization of raw and chemically activated natural zeolite as a potential sorbent for heavy metal ions from waste water

Abstract

In this study, raw and chemically activated natural zeolite from Zlatokop deposit (Serbia) were investigated by FTIR, XRD, SEM-EDX, TGA and BET in order to define their properties as further potential sorption materials. Obtained results indicate porous (meso-pore range) and defined crystal alumino-silicate structure of these materials, with Na+, K+, such as Ca2+ and Mg2+ as dominating exchangeable cations. Content of clinoptilolite (ca. 90%) indicates the high quality of the zeolite samples. Preliminary sorption analyses of these materials toward copper(II) ion from aqueous solution showed good removal efficiency for base activated zeolite (zVBB) compared to raw natural (zVBN) and acid activated (zVBA) zeolite. Since these were preliminary sorption tests, the investigated zeolites will be further examined under different experimental conditions.

Modification of Clinoptilolite as a Robust Adsorbent for Highly-Efficient Removal of Thorium (IV) from Aqueous Solutions

“…The existence of this type of hysteresis loop is considered to be a characteristic for the clinoptilolite material, which can be attributed to multilayer physical adsorption followed by capillary condensation either in the space between the crystallites of zeolite or in mesopores of impurities (quartz, feldspars, etc.) [ 45 , 51 , 52 ].…”