Radiochemical reaction of DT/ T2 and CO under high pressure

•The radiochemical reactions between D–T/T and CO of different concentrations under 1.0 MPa were elucidated.•Only tritium was involved in the reaction of CO, and the reaction rate was in direct proportion to tritium concentration.•CT2O are major products under β irradiation of tritium. For both fuel cycle design and safety evolution of tritium (T) in fusion reactor, it is important to study irradiation-induced reactions between T2 and various molecular species produced from nuclear-fusion fuel cleanup systems. The radiochemical reactions between deuterium-tritium/tritium and carbon monoxide of different concentrations under 1.0 MPa were elucidated in this work. The products and the process of radiochemical reactions of T2/CO and D2-T2/CO mixed system with different tritium concentrations were analyzed by mass spectrometry and gas chromatography. The evolution of the product composition in 300 min. was monitored at room temperature with a rapid decrease of tritium concentration and pressure. It was found that, in T2/CO and D2-T2/CO mixed system, only tritium was involved in the reaction of CO. Under the β irradiation of tritium, the reaction products were mainly composed of tritiated formaldehyde (CT2O) and tiny amount of CO2, C(DT)4, C3(DT)8. The concentration of products rose with the increase of CO concentration in reaction system.