Influence of calcination temperature on surface acidity of the solid superacid of sulfated alumina

The acidity of sulfated alumina catalysts was studied by analyzing DTG and heat of Ar adsorption together with the isomerization of pentane. The initial acid sites were Brönsted-type, and converted into Lewis-type upon increasing the pretreatment temperature. The heat of Ar adsorption of the most active sulfated alumina was 18.9 kJ mol^–1, this value being a little smaller than that of sulfated zirconia (23.6 kJ mol^–1).This revised version was published online in December 2005 with corrections to the Cover Date.