Radiation chemical reactions in carbon dioxide-propane system

Radiolysis of the CO2-C3H8 system by fission fragments (FF) was compared experimentally with those by γ- and (n+γ)-rays. Carbon monoxide formation was observed to reach maximum at 1% propane concentration with all three kinds of radiation. The G(CO) value was found consistently higher with FF than with γ- and (n+γ)-rays, whereas G(C2H6) showed the opposite tendency in the difference between FF and the other radiations. The maximum G(CO) value obtained with FF was 6.7, while only 3.6 was attained with the other radiations. The difference between the radiolysis by FF and by the other radiations was ascribed to reactions taking place within the FF tracks. The rates of in-track reactions and the diffusion out of the tracks were estimated on the basis of Mozumder's track model. This estimation made it clear that, with the rise in the total pressure, CO formation could be expected to be enhanced by FF irradiation, with the reaction CO2++e- → CO+O coming to predominate over other reactions constituting the mechanism of CO2 radiolysis. (auth.)