Increase in activity of hydrophobic platinum catalyst for oxidation of tritium by irradiation with electron beams

Iwai, Yasunori

no journal, , 

Hydrophobic platinum catalysts have been widely applied in the field of nuclear fusion such as to the exchange reactions of hydrogen isotopes between hydrogen and vapor and to the oxidation reactions of tritium. Hydrophobic platinum catalysts are hardly susceptible to water mist and water vapor. Hydrophobic platinum catalysts are produced by supporting platinum directly on hydrophobic polymer beads. For the hydrophobic polymer, styrene divinyl benzene (SDB) has been applied in Japan. It can be pointed out that the betterment in catalytic activity of hydrophobic catalyst is expected to downsize the catalytic reactor based on a hard look at a large increase in flow rate in future. The acute change in catalytic activity of two types of commercial Pt/SDB catalysts was found when they were irradiated with electron beams. After irradiation with electron beams, the catalytic activity was evaluated by means of overall reaction rate constant for the oxidation of tritium. The overall reaction rate constant increased as increase in dose. The constant showed the peak value in the dose between 500 to 1000 kGy. After the peak, the constant decreased as increase in dose. The overall reaction rate constant at the peak was 6 times larger than that evaluated with unirradiated. The mechanical strength of irradiated Pt/SDB kept sound until 1500 kGy. The irradiation is a promising method to the betterment in catalytic activity of Pt/SDB catalyst.