Cs-leaching behavior of Cs-titanosilicate in NaCl solution

Cs-titanosilicate, which is a pollucite-related phase, was synthesized and the Cs-leaching behavior of Cs-titanosilicate was evaluated in a NaCl aqueous solution and ion-exchanged water. CsNO 3, TiO 2 and SiO 2 powders were mixed in ethanol by ball-milling and then the mixed powder was heated at temperatures of 600 to 900 °C under atmospheric and reduced pressures of air. Under reduced pressure, the Cs-titanosilicate phase was crystallized at 700 °C, which was lower than that under atmospheric pressure because CsNO 3 decomposition was promoted under reduced pressure. The Cs-leaching ratio of the Cs-titanosilicate in a NaCl aqueous solution is higher than that in ion-exchanged water. On the other hand, the Cs-leaching ratio of the Cs-titanosilicate synthesized under the reduced pressure was lower than that under atmospheric pressure. It was considered that the lower negative zeta potential of the Cs-titanosilicate synthesized under the reduced pressure diminished the amount of Na + ion adsorbed on the particles surface of the Cs-titanosilicate, which resulted in the suppression of Cs-leaching.