Vapor-Phase Radiolysis of Propane-d8 in the Presence of Other Hydrocarbons

The radiolysis of propane‐d₈ has been investigated in the presence of saturated and unsaturated hydrocarbons. Radical scavengers have been added in all experiments in order to prevent the production of hydrogen, methane, ethane, and ethylene by neutral thermal radical reactions. The formation of ethane could be ascribed mainly to the occurrence of the hydride‐transfer reactions $${\mathrm{C}}_2{\mathrm{D}}_5^{+}+{\mathrm{C}}_3{\mathrm{D}}_8\to {\displaystyle {lim}_{k_1}}{\mathrm{C}}_2{\mathrm{D}}_6+{\mathrm{C}}_3{\mathrm{D}}_7^{+}$$ and $${\mathrm{C}}_2{\mathrm{D}}_5^{+}+\mathrm{RH}\to {\displaystyle {lim}_{k_2}}{\mathrm{C}}_2{\mathrm{D}}_5\mathrm{H}+{\mathrm{R}}^{+}.$$ When RH=saturated hydrocarbon, the values of k₂/k₁ increase with increase in the molecular weight of RH. The observation that olefins and aromatic compounds lower the yield of ethane, but do not affect the rates of formation of molecular methane and ethylene, led to the conclusion that ethyl ions may add to the unsaturated hydrocarbons. Evidence has been obtained for a molecular elimination of hydrogen, methane, ethane, and ethylene from several of the hydrocarbons.