SO42-/TiO2/Al-pillared clay (STALI-PILC) superacid was prepared by loading active component SO42-/TiO2 on Al-pillared clay. The texture structure properties of the catalyst were studied by means of x-ray powder diffraction and the adsorption of N-2. Acidity properties of the catalyst were tested by Hammett indicator method and FT-IR spectra of adsorbed pyridine technique. The characterization results indicated that Al-PILC carrier could inhibit the information of anatase TiO2 and the transformation of anatase TiO2 into rutile TiO2. ST/Al-PILC catalyst possesses both Lewis and Bronsted acid sites, and the number of acid sites on ST/Al-PILC is much larger than that on Al-PILC carrier, but its acid strength is lower than that of ST. Experimental results show that ST/Al-PILC is an effective catalyst for esterification of n-pentanol with benzoic acid. (C)2004 Elsevier B.V. All rights reserved.