Adsorption and oxidation investigations over Pt/Al2O3 catalyst: A microcalorimetric study

Abstract

The differential adsorption heats of oxygen and NO, as well as catalytic oxidation behavior during NO oxidation and NO2 dissociation reactions over supported Pt-catalysts, were investigated by microcalorimetric measurements. The average heat of adsorption (DH) of oxygen ranged from 310 kJ/mol at 200°C to 289 kJ/mol at 400°C. Over this temperature range formation of platinum oxides and coverage dependence caused variations in the apparent heat of adsorption. NO heat of adsorption from 50 to 150°C was near constant with an average value of 202 kJ/mol over the temperature range.