Selective removal of Cs+ and Sr2+ by electrosorption using intercalating titanosilicate

Abstract

The utilization of ion intercalate capacitive deionization technology is garnering attention as an electrified water treatment method. This study proposes a capacitive deionization technology incorporating Dual-cation TitanoSilicate (DTS) to enable efficient electro-sorption/desorption of radioactive ions Cs and Sr. The synthesized DTS possesses a robust structure, high selectivity for Cs and Sr, and substantial adsorption capacity, incorporating redox-active titanium. Employing DTS as an active material in the electrode demonstrated a high adsorption capacity (186 mg Cs/g, 177 mg Sr/g) and rapid adsorption kinetics, reaching maximum capacity within 30 min, even in environments with a tenfold excess of competing ions. Furthermore, our system exhibited stable performance over 5 cycles of adsorption/desorption, and post-desorption analyses confirmed the durable structure stability without significant alterations. This study highlights the feasibility of CDI technology utilizing DTS for cesium and strontium removal.