Liquid-phase dehydration of 1-phenylethanol over mordenite-like zeolites: Influence of Si/Al ratio

The liquid-phase dehydration of 1-phenylethanol over mordenite-like zeolites, with different Si/Al ratios, was studied at 363 K using cyclohexane as solvent. It was determined that catalyst activity and selectivity greatly depended on the Si/Al ratio. The non-dealuminated mordenite showed the lowest activity, dehydrating 1-phenylethanol mainly to α-methylbenzyl ether via an intermolecular mechanism. Instead, intramolecular dehydration of 1-phenylethanol into styrene was mainly observed over dealuminated samples. Changes in catalytic performance with Si/Al ratio was explained on the basis of: (1) acid site density; (2) relative amount of strong acid sites respect to weak ones; (3) accessibility to strong acid sites.