Preparation of Phosphotungstic Acid with Dawson Structure through Hydrothermal Method and Its Catalytic Activity in the Synthesis of Cyclohexene

Phosphotungstic acid with Dawson structure was prepared by hydrothermal method,and it was applied in the catalytic synthesis of cyclohexene.When the mass of the catalyst used was 4.2% of the quantity of cyclohexanol,the reaction temperature was about 170～180 ℃,and the reaction time was 35 min,the yield of cyclohexene could reach more than 93.0%.The catalyst could be reused for 5 times and the yield was still above 75.0%.It was a typical simple and practical new green route to the synthesis of cyclohexene.