Hydrogenolysis of CFC-12 (CF2Cl2) over Pd/γ-Al2O3 pretreated with HCFC-22 (CHF2Cl)

Abstract The hydrogenolysis of CF 2 Cl 2 (CFC-12) has been studied in the gas phase over Pd (3 wt.%)/γ-Al 2 O 3 . Pretreatment of the catalyst with CHF 2 Cl (HCFC-22) was found to significantly improve the catalytic activity and the catalyst lifetime. The formation of Pd-carbide was observed in the CHF 2 Cl-treated catalyst, and the presence of the palladium carbide is thought to enhance the selectivity to the CH 2 F 2 and to prevent sintering of palladium. XRD, TEM and XPS were used to characterize the structure and the composition of Pd/Al 2 O 3 .

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