HYDROGEN CONTENT AND HYDROGENATION ACTIVITY OF MOS2 GAMMA-AL2O3 AND GAMMA-AL2O3 MECHANICAL MIXTURES/

The hydrogen content and the reactivity Of MoS2/gammaAl2O3 catalyst an d gammaAl2O3 support mechanical mixtures have been investigated using high pressure toluene hydrogenation, hydrogen temperature programmed d esorption (H-2-TPD), and oxygen chemisorption. It has been found by H- 2-TPD and confirmed by the oxygen chemisorption that, in the presence of a MoS2/gammaAl2O3 catalyst, the gammaAl2O3 support contains some hy drogen species. These species are therefore provided by spillover from the MoS2 phase which possesses the active sites able to dissociate mo lecular hydrogen. However, no cooperative effect of mechanical mixture s on toluene hydrogenation activities obtained in typical hydrotreatin g conditions, i.e., 6 MPa and 350-degrees-C, both in the presence and in the absence of a H2S partial pressure, has been found. (C) 1994 Aca demic Press, Inc.