Conversion of ethanol and isopropanol on alumina, titania and alumina-titania catalysts

Abstract

Alumina, titania and alumina-titania hydrogels were precipitated from the respective chloride solutions. Catalysts calcined at 400–900°C were characterized by DTA, X-ray diffraction and nitrogen absorption. The acidity of the catalysts has been determined by the amine titration method and the catalytic activity of these catalysts towards the conversion of ethanol and isopropanol was determined at different temperatures. Al 2O 3-TiO 2 catalysts are more active in dehydrating alcohols than single oxide catalysts. Dehydration of alcohols is related to the amount of surface acidity rather than to the strength of surface acid sites. The chemical composition and calcination temperature of mixed oxides are among the factors affecting the performance of the catalyst towards the conversion of alcohol. The conversion temperature plays a prominent role in determining the selectivity of the catalyst. The conversion of alcohols via dehydration seems insensitive to the surface area of alumina, titania or alumina-titania catalysts.