Korea’s Activities for the Development of a Detritiation System

Abstract

Tritiated gas and water should be properly treated to minimize an environmental tritium emission in nuclear fusion research facilities. Tritiated gas is usually treated in two steps: it is first oxidized to a tritiated water vapor by a catalyst and then the vapor is adsorbed in a molecular sieve drier. We have used a 1wt.% Pt/SDBC polymer catalyst and Zeolite 13X for the tritiated gas removal system. We confirmed that the decontamination factor of the equipment was more than 100 under a gas flow rate of 90 liters/hr and at a temperature of 65-80 °C.Furthermore we have developed a tritiated organic liquid treatment process. We have used a 0.5wt.% Pd/Al₂O₃ catalyst to oxidize an organic liquid. The simulated organic liquid was converted to water by over 99%. We have also developed a small scale CECE (Combined Electrolysis and Chemical Exchange) process by combining an LPCE (Liquid phase Catalytic Exchange) catalytic column with SPE (Solid Polymer Electrolyte) electrolysis. The experimental results of the CECE process produced a decontamination factor of 13-20. We used the electrolyte Nafion 117 which was coated with Pt as a cathode catalyst and IrO₂ as an anode catalyst. We also tested a palladium alloy membrane for a purification of the hydrogen in the detritiation process.