CHEMISORPTION OF HYDROGEN AND OXYGEN ON GAMMA-ALUMINA-SUPPORTED RHENIUM .1. CHEMISORPTION OF HYDROGEN

The chemisorption of hydrogen on γ-alumina-supported rhenium (10.4 wt.% and 1.04 wt.%) has been investigated gravimetrically, using a Cahn RG (HV) electrobalance, with respect to time (within 300 min), pressure (50-250 Torr, 1 Torr = 133.3 N m-2) and temperature (20-550°C). Some results are compared with earlier data obtained volumetrically on rhenium powder. The chemisorption of hydrogen on supported rhenium was found to be similar to that on rhenium powder and is, in part, slow, thermally activated and, at each temperature in the applied range, partially or completely reversible. The applicability of hydrogen chemisorption, under properly chosen conditions, for the determination of the surface area and dispersion of supported rhenium is indicated and the dispersion data resulting from that determination are given. © 1990.