Abstract
MO-Al2O3 (M = Mg、Ca、Sr、Ba) supports were prepared by impregnating nitrates of alkaline earth metals into Al2O3. The bacisity of impregnated supports was studied by CO2 adsorption in a combined system of volumetric adsorption system and micro-calorimeter. From measured heat of CO2 adsorption, the basi-city of MO-Al2O3 supports was found to vary with the property of alkaline earth metals impregnated, nevertheless the density of strong adsorption sites was invariantly increased with loading of A.E. metals (up to 20 wt%). Neither Al2O3 nor MO-Al2O3 showed significant affinity towards NO. However, this molecule could be strongly adsorbed on samples of Pd/Al2O3 and Pd/MO-Al2O3 prepared by impregn-ating the corresponding supports with Pd(NO3)2. The sites density and the heat of NO adsorption on the prepared samples increased monotony only with their loading and dispersion of palladium. Among the studied samples, Pd/SrO-Al2O3 with 10 ~ 20 wt% loading of Sr metals exhibited about good NO adsorption ability. This strontium modified sample is a good trap material for removing NO pollutant from exhaust gases.