Cesium Removal from Waste Seawater by Nanocrystalline Mordenite

Abstract

Up to the present, the process for the liquid waste with high salt content such as the waste seawater generated from the unexpected accident of nuclear power plant has not been studied extensively. In this study, the adsorption efficiencies of Cs in the seawater environment were investigated using mordenite, a type of zeolite, with different particle sizes. Commercial and synthesized mordenites were used for the treatment of the simulated liquid waste based on the seawater containing Cs, and the reaction kinetics and adsorption capacities of nano-sized mordenite were compared with those of bulk scale mordenites. The experimental results clearly showed that the nano scale adsorbent showed fast adsorption kinetics and high binding capacity for Cs. Also, the nano-sized mordenite are well-dispersed in the solution as a colloid, thus, it could be successfully applied to the static adsorption condition. Interestingly, the colloidal mordenite gradually flocculated in the seawater condition. Since self-flocculation occurred after the maximum adsorption of Cs, even in the static condition, it might be beneficial to separate the solid particles from the solution.