Efficient Removal of Cesium Ions from Radioactive Wastewater Using Na+-Intercalated Layered Manganese Oxide via Solid-Phase Synthesis

Abstract

Efficient capture of radioactive cesium is critical for the long-term development and environmental protection of nuclear energy. This article reports the preparation of Na+-based cation-intercalated manganese oxide (CIMO) via a solid-phase reaction method and their application to the removal of cesium ions from simulated radioactive wastewater. Among them, the manganese oxide structure obtained by Na+ intercalation is of particular interest due to its unique layered structure, excellent physicochemical properties, and excellent adsorption performance for cesium. According to the experimental findings, the layered manganese oxides exhibit outstanding affinity for Cs+ across a broad pH range of 2–8. The maximum adsorption capacity of CIMO for Cs+ is 204.23 mg/g, and the layered manganese oxide exhibits good recyclability. Additionally, in the presence of competing ions and in multiple real wastewater samples, CIMO showed exceptional adsorption removal capability for Cs+. Furthermore, it was shown that the mechanisms by which CIMO removes Cs+ ions are Na+/Cs+ ion exchange and surface electrostatic interactions. Therefore, because of its easy production and environmental friendliness, CIMO can be regarded as a potential adsorbent for the effective removal of Cs+ from radioactive waste water.