The removal of cesium ion with natural Itaya zeolite and the ion exchange characteristics

BACKGROUND The large Itaya zeolite deposit in Yonezawa, Japan produces good quality, natural zeolite. Its properties as an adsorbent and a functional carrier were assessed and the ion exchange characteristics examined. Natural zeolite has a useful high cation exchange capacity, but has a disadvantage in scattering of the powder. In this study a nonwoven fabric containing zeolite was tested for the removal of cesium. RESULTS The X‐ray diffraction (XRD) peak pattern confirmed that Itaya zeolite is mainly clinoptilolite and contains some mordenite. Ion exchange selectivity of the natural zeolite was Ag+ > Pb2+ > Cu2+ > Zn2+ > Cd2+ > Cr3+ > Ni2+ with almost 100% removal of Ag+ and Pb2+ ions. The cation exchange capacity (CEC) of Itaya zeolite was 131 cmol kg‐1. Low concentrations of Cs+ were removed effectively from the solution with natural zeolite. Cesium ions were removed by ion exchange with potassium and sodium. Cs+ was desorbed from the zeolite with ammonium salt solutions. Elution of Cs+ was influenced by the coordination ability of counter anions. CONCLUSION Satisfactory results were obtained using zeolite‐containing nonwoven fabric for the removal of cesium ions. © 2013 Society of Chemical Industry