Studies on H_2S Adsorption and Carbon Deposition Over Mo-Ni/Al_2O_3 Catalysts

摘要

The influence of molybdenum on the CO_2 reforming of methane, simultaneous sulphur poisoning and carbon formation over alumina-supported Ni catalysts was studied. A series of Ni/Al_2O_3 catalysts modified by Mo was prepared to enable the effect of molybdenum content on H_2S adsorption and the catalytic properties of the solids to be studied. The atomic Mo/Ni ration in such catalysts varied in the range 0.01-1.00 while the Ni content was maintained constant at 3.3%. The catalysts were characterized by TPR, hydrogen adsorption and TEM methods. The H_2S adsorption capacities of the catalysts were determined at 923 K employing a mixture consisting of 50 ppm H_2S in a hydrogen stream. The results obtained indicate that the Mo promoter had a very favourable influence on the sulphur resistance of the Ni-based catalyst and led to a reduction in the rate of carbon deposition and the formation of graphitic species over the same.