Active catalysts for the butane conversion were obtained by mechanically mixing Pt-ZrO2 and sulfated metal oxides (SO4-MeOx), zeolites, or silica-aluminas. Pt-ZrO2 was prepared by the impregnation of zirconia gel with aqueous H2PtCl6. 6H(2)O, followed by calcination at 750 degrees C (0.5 wt.% Pt). The activity order of SO4-MeOx was SO4-TiO2>SO4-Al2O3>SO4-Fe2O3>SO4-SiO2; the alumina catalyst gave the highest selectivity for the skeletal isomerization, i-C-4, 78% with 25% conversion at 220 degrees C under the pulse reaction conditions. No effect of the Pt addition was found when prepared by co-impregnation of metal oxides with sulfate and Pt materials. The effect of mixing with zeolites and silica-aluminas showed satisfactory conversions of butane. Mordenites were highly active, but the selectivity for i-C-4 was relatively low, similar to 50% at 200 degrees C. Silica-aluminas and other zeolites, ZSM-5 and Y-type, were also active at 200 degrees C-240 degrees C, but most of the products were cracked materials : methane, ethane, and propane. The selectivity for i-C-4 highly increased by sulfation of the silica-aluminas to >53%.