Removal of Radioactive Cesium and Strontium by Zeolites

Abstract

Selective removal of Cs and Sr from high-activity-level water (HALW) has been studied by the use of various kinds of zeolites, i.e., A, X, chabazite(C) and mordenite(M). Breakthrough behaviors were examined by passing the solution containing Cs+ and Sr2+ through a column packed with zeolites in Na+ form. At the flow rate (SV) of 25, S-shaped break-through curves were obtained for Cs. However, strontium, adsorbed on chabazite and mordenite, was partially eluted in the feed solution with replacement of Cs due to a strong affinity of Cs for these zeolites. This elution of Sr resulted in a temporary concentration of Sr and a lowering of total capacity. As for the mixed zeolite columns, break-through properties of Cs and Sr almost corresponded to the combination of those of individual zeolites. The mixture of C/X with an appropriate ratio of 1 : 3 was effective for the one-through removal of Cs and Sr. © 1989, The Chemical Society of Japan. All rights reserved.