The optimum conditions for the synthesis of borneol via the reaction of α-pinene and oxalic acid in the presence of nanometer solid superacid catalyst SO2-4/ZrO2 were obtained. The results show that when the mole ratio of α-pinene to oxalic acid was 1∶0.4, the mass fraction of the catalyst SO2-4/ZrO2 to （α-pinene） 3%, the reaction time 6 h, and the reaction temperature program was 65 ℃ for 1 h, 75 ℃ for 4 h, 90 ℃ for 1 h, the yield of crude product （borneol） reached 70.9%. This method offers little pollution, high yield, mild （reaction） condition, good processing safety, and catalyst reusability.
Isoborneol could be selectively prepared in high yield from camphene and oxalic acid by the way of esterfication-saponification method in the presence of nanometer solid superacid SO42-/ZrO2.The research showed when the esterification reaction temperature was 70℃,the esterification reaction time was 7 h and the use level of catalyst was the mass of camphene of 6%,the conversion of camphene could reach 80.5% and the purity of isoborneol could reach 100%.Furthermore,the components and their contents in light oil（after drying） obtained from wet distillation after esterfication reaction were the same as those in raw material camphene and it could be reused.In addition,the mechanism of the synthetic reaction and the factors influencing the reaction were studied.The particle size,surface area,acidity and the structure of nanometer solid superacid SO42-/ZrO2were also characterized and discussed.
