Hydrodechlorination of chlorobenzene on Nb2O5-supported Pd catalysts influence of microwave irradiation during preparation on the stability of the catalyst

Catalytic hydrodechlorination of chlorobenzene was studied on Pd/Nb2O5 catalysts prepared by the conventional and the microwave heating techniques. The catalysts were characterized by X-ray diffraction (XRD), BET surface area, hydrogen chemisorption and scanning electron microscopy (SEM). The time-on-stream studies reveal that the microwave-irradiated catalyst exhibits better resistance towards deactivation than the conventionally prepared catalyst. Microwave irradiation also seems to be preferable than the high-temperature reduction adopted to increase the particle size. The microwave-irradiated catalyst also shows higher residual activity than the electrically heated catalyst at all reaction temperatures studied. This is attributed to the formation of larger particles of palladium which is in conformity with the basic observation made in the literature that hydrodechlorination is more facile on low-dispersed Pd catalysts. (C) 2002 Elsevier Science B.V. All rights reserved.