[1C01-04] Severe Accident

[1C01] High-temperature gas-solid interaction of calcium silicate insulation with cesium hydroxide

*Muhammad Rizaal¹, Kunihisa Nakajima¹, Masahiko Osaka¹, Takumi Saito², Koji Okamoto² (1. Japan Atomic Energy Agency, 2. The University of Tokyo)

Keywords:Cesium, Calcium silicate insulation, Gas-solid chemical interaction, CsAlSiO4

Here we report an experimental study to investigate cesium retention on calcium silicate insulation following the gas-solid chemical interaction at high temperature. This study used cesium hydroxide and was performed at 800ºC under the oxidizing atmosphere. The experimental results showed that water-insoluble CsAlSiO₄ and dicalcium silicate/larnite (Ca₂SiO₄) were formed, which evidences that the insulation material could retain Cs in a stable form.