Hydrogen-assisted dechlorination of CF3OCFCl-CF2Cl to CF3OCF=CF2 over different metal-supported catalysts

In this work the hydrogen-assisted dechlorination of CF3OCFClCF2Cl to produce unsaturated CF3OCF=CF2 was studied over a series of metal catalysts supported on activated carbon. The results obtained indicated that the activity, stability, and selectivity of the materials were strongly dependent on the metal used. The activity of the monometallic catalysts follows the order Pd/C > Ru/C> Ni/C, while the sequence Ru/C > Ni/C > Pd/C was found for the selectivity to the target product. A wide diversity in reaction products was obtained with these materials. Pd-supported samples mainly yield saturated products. In contrast, CF3OCF=CF2 was the product most formed with Ru/C catalysts which, nevertheless, showed the lowest stability. However, when Ru or Cu was added to Pd catalysts, some very active, stable, and selective materials were obtained. Spent samples were characterized by TPD/MS, TGA, XRD, and FESEM techniques. The results obtained revealed that Ru-based catalyst deactivation was mainly due to the formation of heavy halogenated carbonaceous deposits. (C) 2013 Elsevier B.V. All rights reserved.