The effect of solvents with variant polarity was investigated in liquid-phase rearrangement of styrene oxide to phenylacetaldehyde over HZSM-5 zeolite. The experimental results showed that DMF,which possessed the strongest polarity,could be easily adsorbed on the surface of zeolites and resulted in quick deactivation of the catalyst. Other solvents with weaker polarity could improve the reaction rate effectively,while by-products were generated by reacting with phenylacetaldehyde. The weakest polar or nonpo...