Mixed oxides of alumina and zirconia having a relative composition of 50, 80 and 100% Zr2O were synthesized by means of sol-gel methods. The catalysts were sulfated with H2SO4 1N, and were loaded with 0.3% Pt metal using the incipient wetness technique. The characterization of the physicochemical properties was carried out using XRD, N-2-adsorption at 78 K, and SEM. The catalytic properties of the Al2O3-ZrO2 series were studied by means of dehydration of 2-propanol at 180 degreesC and isomerization of n-hexane at 250 degreesC, 1 atm. The sulfated solids presented a high surface acidity and a limited crystallinity, together with high activity for alcohol dehydration (i.e. 2-propanol). On the other hand, the Al2O3-ZrO2 solid solutions (i.e. those having a 20-80% composition) turned out to be the most active ones for the isomerization of n-hexane.