Abstract: 4 kinds of SO3H-functionalized quaternary ammonium ionic liquid were prepared by two-step method. Their IR and NMR spectra showed that their structures were in accordance with their theoretical structure. Their decomposition temperatures shown by TG were higher than 200℃, so they were enough stable as the catalyst in synthesis of biodiesel. Biodiesel was synthesized with triolein and methanol catalyzed by the 4 kinds of ionic liquid prepared. Their catalytic activity was related to their anion structure, and [n-But3N(CH2)3SO3H][CH3SO3] showed the best catalytic activity. The effects of reaction time, molar ratio of methanol to triolein and catalyst amount on the yield of fatty aid methyl ester were investigated when [n-But3N(CH2)3SO3H][CH3SO3] was selected as the catalyst of transesterification reaction. Under the conditions of molar ratio of methanol to triolein at 12:1, mass fraction of ionic liquid 7%(w), reaction temperature 65℃ and reaction time 24 h, the yield of fatty aid methyl ester reached 89.65%, and the ionic liquid was stable during the reaction and could be reused.

Key words: biodiesel, functionalization, [n-But3N(CH2)3SO3H][CH3SO3], ionic liquid, transesterification

摘要： 采用两步合成法制备了4种SO3H-功能化季铵盐离子液体，红外与核磁共振光谱表征结果表明，其结构符合理论结构特点. 热稳定性分析表明，其分解温度都在200℃以上，均可作为制备生物柴油的催化剂. 将这4种离子液体用于催化制备生物柴油，其催化活性主要与其阴离子的结构有关，[n-But3N(CH2)3SO3H][CH3SO3]的催化活性最好. 甲醇:三油酸甘油酯摩尔比为12:1、催化剂用量7%(w)、在65℃下反应24 h时，油酸甲酯产率最高(89.65%). 催化剂重复使用性能良好.

关键词: 生物柴油, 功能化, [n-But3N(CH2)3SO3H][CH3SO3], 离子液体, 酯交换