Characteristics of Honeycomb Oxidizing Catalysts to Recover Tritiated Hydrogen and Methane Gases

For a large volume air cleanup system in nuclear fusion facility, honeycomb type oxidizing catalyst and absorbing dehumidifier offer a useful advantage in terms of their low pressure drop. In the present study the weight ratio of Pd catalyst on the metal honeycomb of Al-Cr-steel alloy were varied from 0.1 g/L to 4g/L. Catalyst was heated up to over 400 °C with stepwise under flowing air containing hydrogen and methane, and their oxidizing reaction rate was evaluated. Its catalytic activation energies were estimated to be about 36 kJ/mol for hydrogen and 100 kJ/mol for methane. Also it was appeared that the effectiveness of high Pd weight ratio catalyst and high temperature operation, and the limit of previous activation by hydrogen gas.