In situ ~(13)C MAS NMR study of ~(13)C-labeled n-butane isomerization on sulfated zirnmia (SZ) ralalysLs shows that the kinetics of n-butane isomerization on SZ catalyst at ambient temperature arc well mpmsented by Langmuir-Hinshelwood equation for a reversible first order surface reaction. The calculated isranerizatinn reaction rate constant can be used as a measure of the solid superacidity of the catalysts. The new characterization method iwi'iil. H that SZ catalysts synthesized from a combined one pot-alcohol thermal- supercritical fluid drying technique not only have high surface area and high sulfate content but their superacidity and isomeiization activity are also much higher than those of the conventional SZ catalysts, which is very desirable from the practical point of view.

Key words: ZIRCONIUM OXIDE, BUTANE, ISOMERIZATION, SUPERACID, C13NMR, SULFURIC ACID