Interactions between molybdenum and activated carbons on the preparation of activated carbon-supported molybdenum catalysts

The influence of the porous texture and surface chemistry of an activated carbon on the preparation of activated carbon-supported molybdenum catalysts was studied, Activated carbons with various degrees of oxidation were used as supports. Supports and catalysts were characterized by nitrogen adsorption at 77 K, temperature-programmed desorption (TPD), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS), The impregnation with molybdenum produced a reduction of the textural properties. TPD results indicated that there was a transformation of CO2- and CO-evolving oxygen functional groups on the activated carbon as a consequence of the impregnation of molybdenum and that acidic groups were acting as chemical anchorage centers, FTIR and XPS analyses confirmed that interactions were established between molybdenum species and carbonyl and ether surface functional groups. These results indicate that the molybdenum was well distributed and reached the inner porous network of the carbon support. (C) 1998 Academic Press.