Desorption of Cs+ Ions Intercalated in Vermiculite Clay through Cation Exchange with Mg2+ Ions

Cesium ions (Cs+) strongly adsorbed in vermiculite clay (Verm) were efficiently desorbed by reacting with magnesium ions (Mg2+). 70–90% removal of adsorbed Cs+ ions was achieved when Verm loaded with 0.1–100 µmol g−1 Cs+ (corresponding to 0.016–16% of the saturation amount) was mixed with 3.0 mol L−1 aqueous Mg(NO3)2. X-ray analyses and powder X-ray diffraction measurements on solid samples confirmed that ion exchange occurred between Cs+ ions in the interlayer space and Mg2+ ions.