Adsorption characteristics of cesium onto mesoporous geopolymers containing nano-crystalline zeolites

The present study investigates the adsorption of cesium onto high-strength bulk-type mesoporous geopolymers containing nano-crystalline zeolites. Fly ash/slag-based mesoporous geopolymers were synthesized by a hydrothermal treatment. Batch adsorption studies were carried out with different initial cesium concentrations, solution pH values, and contact time with adsorbent. Kinetic and isothermal studies were also conducted against the experimental results to comprehend the mechanism and equilibrium condition of adsorption process. A higher removal efficiency of 96% (against 100 mg/L initial concentration) was observed and the maximum adsorption capacity of the mesoporous geopolymers was found to be 15.24 mg/g. The results showed that these mesoporous geopolymer adsorbents have the potential to be used for the removal of hazardous contaminants from aqueous solutions as selfsupporting sieves. (C) 2017 Published by Elsevier Inc.