Studies On Preparation Of New Solid Base Catalyst And Its Preformance To Transesterification Of Soybean Oils

The four types novel solid base catalystsSBA-15-pr-TBD, SBA-15-pr-TMG,SBA-15-pr-DCOG, SBA-15-pr-NR3OH were prepared by using mesoporous molecularsieve SBA-15as a carrier. The1,5,7-Triazabicyclo[4.4.0]dec-5-ene(TBD),1,1,3,3-tetramethylguanidine(TMG), Dimethyloctadecyl[3-(trimethoxysilyl)propyl]a-mon-ium chloride and1,3-Dicyclohexyl-2-(n-octyl0guanidine(DCOG) were chemically bondedon the SBA-15, respectively. The solid base catalyst were characterized by XRD, SEM,TEM, TG-DTA, XPS, IR and Hammett indicator experiments. The catalytic activities ofthe SBA-15-pr-TBD catalyst toward the transesterification reaction of soybean oil withmethanol were investigated, and the reusability of the four kinds of catalysts was studied.The results indicated that the TBD/SBA-15weight ratio of1/1and the reaction time of48h were the optimal condition to synthesize the catalyst SBA-15-pr-TBD. The soybean oilconversion of95.5%was achieved at423K when a methanol/oil molar ratio of12:1, acatalyst loading of5wt%and a reaction time of6h were employed for thetransesterification reaction. The catalyst SBA-15-pr-TMG was prepared withTMG/SBA-15weight ratio of2/1and the48h reaction time. The high soybean oilconversion of92.2%was achieved at423K when a methanol/oil molar ratio of15:1, acatalyst loading of5wt%and a reaction time of12h were employed for thetransesterification reaction. The DCOG/SBA-15weight ratio of5/2and the reaction timeof48h were used to synthesize the catalyst SBA-15-pr-DCOG. The soybean oil conversionof91.5%was achieved at423K when a methanol/oil molar ratio of15:1, a catalystloading of8wt%and a reaction time of15h were applied for the transesterificationreaction. These three catalysts both had good reusability, and the conversation of soybeanoil was not decreased obviously after the catalysts were used five times. However, theDimethyloctadecyl[3-(trimethoxysilyl)prl)-propyl]ammonium chloride/SBA-15weightratio of1/1and the reaction time of48h were the optimal condition to synthesize thecatalyst SBA-15-pr-NR3OH. The soybean oil conversion of99.2%was achieved at423Kwhen a methanol/oil molar ratio of12:1, a catalyst loading of2.5wt%and a reaction timeof30min were applied for the transesterification reaction. The catalyst SBA-15-pr-NR3OHhad better reusability, and the conversation of soybean oil was not reduced obviously after the catalysts were used seven times.