高校化学工程学报Issue(5)：865-871,7.DOI:10.3969/j.issn.1003-9015.2013.05.022
对甲苯磺酸季铵盐离子液体催化酯交换反应制备生物柴油
Transesterification of Glycerol Trioleate to Biodiesel Catalyzed by p-Toluenesulfonic Acid Quaternary Ammonium Ionic Liquids
摘要
Abstract
Alkane sulfonic acid functionalized p-toluene sulfonic acid ionic liquids with four different cations of quaternary ammonium were synthesized. Their IR and NMR spectra show that their structures are in accordance with their theoritical structure. The TG curves show that they are stable and their decomposition temperatures are above 200℃, therefore they can be used as catalyst for the synthesis of biodiesel. Their acidities were determined by using IR spectroscopic probe with pyridine, the results show that the less or shorter the carbon chain in their cations, the stronger the acidity of the ionic liquid, but the difference is little. Meanwhile, the ionic liquids were used as catalyst to prepare biodiesel from glycerol trioleate, and it was found that the yield of methyl oleate is in the same sequence as the acidity of the ionic liquids, and the n-propyl sulfonic acid-3(ethyl) p-toluene sulfonate ionic liquid plays the best. Effects of ionic liquids dosage, mole ratio of methanol to glycerol trioleate, reaction time and reaction temperature on the yield of methyl oleate were investigated. Under optimal transesterification conditions, n (methanol):n (glycerol trioleate):n ( ionic liquids) =12:1:0.167, reaction time 4 h and temperature 130℃, the yield of methyl oleate could reach 92.16%. After the methanol was evaporated and the glycerol was extracted from the ionic liquid phase with acetic ester, the remainder of the ionic liquid phase was reused directly in the next biodiesel preparing reaction, the results show that the yield of methyl oleate is no reduced obviously, which indicates that Alkane sulfonic acid functionalized p-toluene sulfonic acid ionic liquids with four different cations of quaternary ammonium were synthesized. Their IR and NMR spectra show that their structures are in accordance with their theoritical structure. The TG curves show that they are stable and their decomposition temperatures are above 200℃, therefore they can be used as catalyst for the synthesis of biodiesel. Their acidities were determined by using IR spectroscopic probe with pyridine, the results show that the less or shorter the carbon chain in their cations, the stronger the acidity of the ionic liquid, but the difference is little. Meanwhile, the ionic liquids were used as catalyst to prepare biodiesel from glycerol trioleate, and it was found that the yield of methyl oleate is in the same sequence as the acidity of the ionic liquids, and the n-propyl sulfonic acid-3(ethyl) p-toluene sulfonate ionic liquid plays the best. Effects of ionic liquids dosage, mole ratio of methanol to glycerol trioleate, reaction time and reaction temperature on the yield of methyl oleate were investigated. Under optimal transesterification conditions, n (methanol):n (glycerol trioleate):n ( ionic liquids) =12:1:0.167, reaction time 4 h and temperature 130℃, the yield of methyl oleate could reach 92.16%. After the methanol was evaporated and the glycerol was extracted from the ionic liquid phase with acetic ester, the remainder of the ionic liquid phase was reused directly in the next biodiesel preparing reaction, the results show that the yield of methyl oleate is no reduced obviously, which indicates that the ionic liquids were stable, and could be recoveried and reused.关键词
对甲苯磺酸季铵盐离子液体/酯交换/生物柴油/三油酸甘油酯/回收Key words
quaternary ammonium p-toluenesulfonic acid ionic liquids/transesterification/biodiesel oil/gycerol trioleate/recovery分类
化学化工引用本文复制引用
张晓玲,金春英,林金清..对甲苯磺酸季铵盐离子液体催化酯交换反应制备生物柴油[J].高校化学工程学报,2013,(5):865-871,7.基金项目
国家自然科学基金资助项目(20776057，21246008)；福建省科技计划重点项目(2013H0027)；福建省自然科学基金项目(2011J01048)资助。 （20776057，21246008）
