催化学报 ›› 2007, Vol. 28 ›› Issue (8): 743-748.

• 研究论文 • 上一篇    

吡咯烷酮酸性离子液体的合成及其对酯化反应的催化活性

黄宝华,汪艳飞,张焜,方岩雄,周蓓蕾   

  1. 广东工业大学轻工化工学院, 广东广州 510006
  • 收稿日期:2007-08-25 出版日期:2007-08-25 发布日期:2011-08-19

Synthesis of Pyrrolidonium Acidic Ionic Liquids and Their Catalytic Activity for Esterification of Acetic Acid and Butanol

HUANG Baohua*, WANG Yanfei, ZHANG Kun, FANG Yanxiong*, ZHOU Beilei   

  1. Faculty of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, Guangdong, China
  • Received:2007-08-25 Online:2007-08-25 Published:2011-08-19

摘要: 合成并表征了2-吡咯烷酮硫酸氢盐([Hnhp]HSO4)、1-甲基-2-吡咯烷酮硫酸氢盐([Hnmp]HSO4)、1-甲基咪唑硫酸氢盐([Hmim]HSO4)、1-(3-磺酸基)-丙基-3-甲基咪唑硫酸氢盐([C3SO3Hmim]HSO4)和1-(3-磺酸基)-丙基-2-吡咯烷酮硫酸氢盐([C3SO3Hnhp]HSO4)等以HSO-4为阴离子的质子酸离子液体,并以乙酸和正丁醇的酯化反应考察了这些离子液体的催化活性. 结果表明,当n(n-BuOH)∶n(MeCO2H)∶n([C3SO3Hnhp]HSO4)=1.2∶1∶0.005, 反应温度为120 ℃和反应时间为1 h时,酯收率可达99%以上; 反应结束后离子液体与酯产物可分成两相,而且该离子液体重复使用8次,催化活性没有明显下降. 探讨了阳离子结构及Brnsted酸性对催化活性的影响,考察了离子液体与酯化反应相关组分的互溶性. 结果表明,离子液体的分相性能对催化效果有较大的影响,离子液体的催化活性与其酸性、溶解性密切相关.

关键词: 吡咯烷酮阳离子, 离子液体, 功能化, Brnsted酸性, 乙酸, 丁醇, 酯化, 乙酸正丁酯

Abstract: A series of Brnsted acidic ionic liquids, including 2-pyrrolidonium hydrogen sulfate ([Hnhp]HSO4), 1-methyl-2-pyrrolidonium hydrogen sulfate ([Hnmp]HSO4), 1-methylimidazolium hydrogen sulfate([Hmim]-HSO4), 1-(3-sulfonic acid)propyl-3-methylimidazolium hydrogen sulfate ([C3SO3Hmim]HSO4), and 1-(3-sulfonic acid)propyl-2-pyrrolidonium hydrogen sulfate ([C3SO3Hnhp]HSO4), were synthesized and characterized. The catalytic activity of the acidic ionic liquids for the esterification of acetic acid with n-butanol was measured. Under the optimized conditions ofn(n-BuOH)∶n(MeCO2H)∶n([C3SO3Hnhp]HSO4)=1.2∶1∶0.005, 120 ℃, and1 h,the yield ofn-butylacetate could be greater than 99%. The reaction system exhibited good biphasic behavior when the reaction was completed. There was no appreciable decrease in the yield ofn-butylacetate after the esterification was repeated 8 times. The miscibility of the five acidic ionic liquids with the related components of the reaction was investigated, and their biphasic effects on ester yields were examined. The structure-reactivity and Brnsted acidity-catalytic activity relationships were also studied. The acidity and miscibility of the acidic ionic liquids are the important factors relevant to the catalytic activity for the esterification reaction. The activity of the acidic ionic liquids is in good agreement with their acidity order.

Key words: pyrrolidonium cation, ionic liquids, functionalization, Brnsted acidity, acetic acid, butanol, esterification, n-butyl acetate