In order to study the acid-base properties of the cesium-containing molybdena-alumina catalysts, the amount of adsorbed pyridine was measured and the decomposition of isopropyl alcohol as a probe reaction was carried out. As the cesium-content was increased, the dehydration activity of isopropyl alcohol was decreased and the dehydrogenation activity passed through a maximum.
Adsorbed amount of pyridine was increased with increase in cesium-content.
These results suggest that cesium additives lead to decrease the amount of acid sites.