Abstract:

Na₂SiO₃/ZrO₂ solid base catalysts were prepared by immersion method and used to catalyze soybean oil to produce biodiesel.The effects of the different calcination temperature,calcination time,amount-of-substance ratio of silicon to zirconi-um,amount-of-substance ratio of alcohol to soybean oil and mass ratio of catalyst to oil on the transesterification reaction were investigated.XRD characterization results showed that the crystalline structure of ZrO₂ of the catalysts with addition of Na₂SiO₃ were improved.The determination results of catalysts indicated that when the calcination temperature was 600 ℃,cal-cination time was 3 h,amount-of-substance ratio of silicon to zirconium was 4,amount-of-substance ratio of alcohol to soybean oil was 7 and the catalyst dosage was 3% of soybean oil quality,then the highest yield of biodiesel reached 92.5% .

Key words: biodiesel, transesterification, Na₂SiO₃/ZrO₂, solid base