Removal of Barium from Solution by Natural and Iron(III) Oxide-Modified Allophane, Beidellite and Zeolite Adsorbents.

Efficient capture of barium (Ba) from solution is a serious task in environmental protection and remediation. Herein, the capacity and the mechanism of Ba adsorption by natural and iron(III) oxide (FeO) modified allophane (ALO), beidellite (BEI) and zeolite (ZEO) were investigated by considering the effects of contact time, temperature, pH, Ba concentration, adsorbent dosage, the presence of competitive ions and adsorption-desorption cycles (regenerability). Physicochemical and mineralogical properties of the adsorbents were characterized by XRD, FTIR, SEM with EDX and N physisorption techniques.