The deactivation of Pd/C catalyst in the hydrodechlorination of the two chlorofluorocarbons CClF(2)-CF(3) (CFC-115) and CF(2)Cl(2) (CFC-12) into their corresponding hydrofluorocarbons CHF(2)-CF(3) (HFC-125) and CF(2)H(2) (HFC-32) has been systematically investigated. Besides Pd/C catalyst, Pd black was used as a model catalyst in order to exclude the effects of carbon support. The results show that Pd/C catalyst is more efficient for the catalytic hydrodechlorination of CFC-115 than that of CFC-12. From the XRD, TEM, and H(2)-TPR characterizations, it can be concluded that the deactivation of Pd/C catalysts in the hydrodechlorination of CFC-115 at 673 K, a weight hourly space velocity (WHSV) of 2400 ml g(-1)(catal.) h(-1) and a H(2):CFC-115 molar ratio of 2 is mainly attributed to the sintering of the active species Pd particles while the catalyst deactivation in the hydrodechlorination of CFC-12 at 553 K, a WHSV of 1000 ml g(-1)(catal.) h(-1) and a H(2):CFC-12 molar ratio of 4 is due to the carbonaceous deposits. Additionally, the deactivation mechanisms of Pd/C catalysts in the two different hydrodechlorination reactions are discussed. (C) 2011 Elsevier B.V. All rights reserved.