Abstract: Mesoporous carbon-based solid acid catalysts were prepared by carbonization-sulfonation method with SiO2 as a template and sucrose as carbon source. The catalysts were characterized by acidimetric analysis, BET, XRD, FT-IR and SEM. The effects of carbonization temperature and sulfonation temperature on the catalyst performance were investigated, then the prepared catalysts were used in transesterification reaction between soybean oil and methanol, and the effects of reaction conditions and the content of fatty acids in the feed were studied. The results show that the optimum preparation conditions of the catalysts for carbonation and sulfonation temperature were 400 ℃ and 170 ℃, respectively; the yield of biodiesel for transesterification reaction between soybean oil and methanol reached 95.94% under the optimum conditions of molar ratio of methanol to soybean oil 30, reaction time 4 h and catalyst dosage of 8% (accounted for the percentage of soybean oil ); The yield of biodiesel is still over 85.46% after the catalyst was reused for five times, ,indicating the good stability of the catalyst. The fatty acids in the feedstock have a negative effect on the performance of the catalyst. However, in the case of 15% fatty acid in the raw material, the biodiesel yield is still over 90%.

Key words: carbonization-sulfonation, mesoporous carbon-based solid acid, transesterification, biodiesel