TAP study of the sorption of CO and CO2 on γAl2O3

The sorption of CO and CO2 on dehydroxylated gamma Al2O3 was studied by means of temperature programmed desorption (TPD) and single pulse experiments in a TAP reactor. The peak temperatures in the TPD responses of CO and CO2 shift to higher values with lower initial surface coverage. The TPD responses have a tail at higher temperatures. Both observations result from a broad distribution of the heat of adsorption of CO and CO2 on gamma Al2O3. Simulation and regression of the pulse responses of CO and CO2 involved a Temkin distribution of the activation energy of desorption. The lower boundary of the activation energy for desorption of both CO and CO2 is 100 kJ/mol. The width of the distributions of the activation energy of desorption of CO and CO2 are, respectively, 5 and 15 kJ/mol. (C) 1999 Elsevier Science B.V. All rights reserved.