Microporous vanadosilicate efficiently removes cesium from wastewater

The effective removal of Cs+ ions from contaminated groundwater, seawater, and radioactive nuclear waste is crucial for public health and for the operation of nuclear power plants. Although several methods for the removal of Cs+ ions have been developed, there is still a need for better methods. Now a team of Korean researchers led by professor Kyung Byung Yoon from the Dept. of Chemistry, Sogang University (Seoul; www.sogang.ac.kr) has reported a novel microporous vanadosilicate with mixed-valence vanadium (V+4 and V+5) ions, which has an excellent ability to capture and immobilize Cs+ from groundwater, seawater and nuclear waste. This vanadosilicate also contains hexadeca-coordinated Cs+ ions, corresponding to the highest coordination number ever observed in chemistry. The performance of Cs+ removers is often compared in terms of their distribution coefficient K d, which is the ratio of the removed amount of Cs+ ions per amount of remover (in grams) to the amount of residual Cs+ ions per mililiter of solution. Among the various sorbents that have been developed, crystalline silicotitanate (CST), currently used at Fukushima, Japan for Cs+ removal from seawater, has been shown to be quite effective. The Korean researchers claim the…