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Hydrogenolysis reactions of CFC-113a catalyzed by various heterogeneous catalysts (Rh/Al2O3, Pd/C, Ni, Al2O3, Active carbon) were investigated in the liquid and gas phases. In the liquid phase reaction, different catalysts showed different activities, but all catalysts used gave high selectivities toward HCFC-123 over 95%. It was noticeable that the neutral Al2O3 showed both a high activity and a selectivity in the liquid phase reaction. In the gas phase reaction, transition metals on carbon(Pd/C, Pt/C) were so active for hydrogenolysis of CFC-113a that they even catalyzed the production reaction of overhydrogenated compounds such as HCFC-133a(CF3CH2Cl) and HFC-143a(CF3CH3). Al2O3, which showed the high activity in the liquid phase reaction, did not show a remarkable activity. When Al2O3 was used in the liquid phase reaction, the hydrogenolysis of CFC-113a proceeded without any side products in THF. However, the same reaction in MeOH produced side products, such as CH3OCH3 and CH3CH2OCH3 from solvent. Based on this result, including heterogeneous catalysts, it was concluded that the solvent played an important role in the liquid phase reaction.
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