Demonstration of Tritium Extraction from Tritiated Methane in Helium by Utilizing Plasma Decomposition

In the tritium recovery system of a fusion reactor, tritium extraction processing from tritiated hydrocarbon is needed. In the present study, a flow-type plasma reactor utilizing capacitively coupled plasma followed by the double tube permeator of Pd-Ag was developed and tritium extraction from tritiated methane in helium was demonstrated. When the helium gas containing tritiated methane was passed through plasma, it was observed that the concentration of tritiated methane decreased and the concentration of HT increased. However, the apparent decomposition rate of tritiated methane was considerably smaller than that of methane. Moreover, the amount of extracted tritium by Pd-Ag was smaller than expected.