IMPROVED HYDROGENATION CATALYSTS FOR COAL-DERIVED LIQUIDS

Benzene, naphthalene and biphenyl hydrogenation in a slurry-phase reac tor were used as probe reactions to investigate the influence of bimet allic catalyst formulations and altervalent carrier doping on hydrogen ation activity and sulphur-poisoning characteristics. It was found tha t addition of a secondary metal such as Pd, Ir or Re to primary metals such as Pt, Rh, or Ru, has a beneficial influence on these parameters . Significant enhancements in hydrogen adsorption capacity, hydrogenat ion activity and sulphur tolerance were observed when metals were disp ersed on TiO2 doped with higher-valence cations. The enhancement facto rs were found to be a function of the dopant concentration in the carr ier. Results related to altervalent carrier doping are explained in te rms of long-range electronic interactions at the metal-support interfa ce which alter the work function of surface metal atoms.