Immobilisation and solidification of cesium on 11Å calcium silicate hydroxy hydrate column

Abstract

Calcium silicate hydrate closely resembling silicate mineral "IIÅ tobermorite" has been synthesised by hydrothermal treatment of lime and silica at 175°C. The synthetic mineral exhibits selectivity for C^s+ in the presence of strong solutions of alkali and alkaline earth cations, viz., Na⁺, K⁺, Mg²⁺,Ca²⁺, Sr²⁺, etc. The AI-substituted form of this mineral effectively separates cesium ion when used as an exchanger in column of size 35x5 mm (hxr), It is possible to remove 98.65±0.5% C^s+ from a mixed solution of cesium and sodium (0.0001<em>N</em> C^s++0.5<em>N</em> Na⁺). Column separation of cesium from simulated intermediate level waste solution shows that from the first run - 76% Cs+ can be immobilised on a small column, 18x10mm (hxr), having 2.0g of exchanger.