Abstract:Methanol and rapeseed oil were used as raw materials to prepare biodiesel under the action of solid acid catalyst. The effects of reaction temperature, alcoholoil ratio, catalyst dosage and microwave frequency on dielectric properties of mixtures were investigated, and the coupling ability of chemical reaction system with microwave was also analyzed. The test results show that under the single factor reaction condition, the dielectric properties of mixture are decreased with the increasing of reaction time. Increasing the reaction temperature and the amount of the catalyst can advance the time for the dielectric constant and loss factor of mixture to stable value, and increasing the molar ratio of alcohol to oil has the opposite effect. The more the molar ratio of alcohol to oil is, the bigger the dielectric loss tangent of mixture is, and the stronger the coupling ability with microwave is. When the microwave frequency is 2 450 MHz, the coupling ability of mixture with microwave is stronger than that of 915 MHz.