Promotion of Ni/MCM-41 Catalyst for Hydrogenation of Naphthalene by co-Impregnation with Polyols

The activities of nickel supported on MCM-41 catalysts, prepared by co-impregnation with polyols (ethylene glycol, glycerol, xylitol, sorbitol and glucose), were investigated by hydro-genation of naphthalene. Compared with the conventional wetness impregnation, addition of moderate polyols into the metal nitrate aqueous solution could enhance interaction with support surface, resulting in formation of very small NiO particle size (<5 nm), high dis-persion of the active phase and significant catalytic activity. Particle size of Ni⁰ decreased from 36.1 nm to below 5 nm; meanwhile the complete hydrogenation of naphthalene was dependent on the Ni0 particle size. The hydrogenation activities of the catalysts prepared by co-impregnation with polyols were very high with 100% conversion even at low temperature of 55 oC.