The C2H4/He reaction on Rh/MgO studied by transient methods

Abstract

The reaction of a 0.5 mol% C2H4/He mixture with 2.5 wt% Rh/MgO at 310 and 533 K was studied by employing transient and temperature-programmed methods. The reaction of C2H4/He at 310 K gives CH4 and C2H6 in the gas phase, whereas the surface species formed desorb and decompose after programming the temperature in He flow. This procedure results in CH4, C2H4, C2H6 and H2 in the gas phase and carbon on the surface. The reaction of C2H4/He at 533 K produces CH4, C2H6 and surface carbonaceous species, but the reaction is quenched after 5 min of continuous feed. The results indicate that this is due to accumulation of carbonaceous species (Θ{round} = 0.82) which prevent further chemisorption of ethylene. © 1991.