Chin. J. Org. Chem. ›› 2015, Vol. 35 ›› Issue (8): 1773-1780.DOI: 10.6023/cjoc201503012 Previous Articles     Next Articles



胡晶晶, 赵地顺, 李静静, 翟建华, 胡甜甜   

  1. 河北科技大学化学与制药工程学院 石家庄 050018
  • 收稿日期:2015-03-10 修回日期:2015-04-21 发布日期:2015-04-27
  • 通讯作者: 赵地顺
  • 基金资助:

    国家自然科学基金(Nos. 20576026, 21106032)资助项目

Synthesis and Catalytic Esterification Performance of Caprolactam Task-Specific Ionic Liquids

Hu Jingjing, Zhao Dishun, Li Jingjing, Zhai Jianhua, Hu Tiantian   

  1. College of Chemical and Pharmaceutical Engineering, Hebei University of Science and Technology, Shijiazhuang 050018
  • Received:2015-03-10 Revised:2015-04-21 Published:2015-04-27
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Nos. 20576026, 21106032).

Four kinds of caprolactam task-specific ionic liquids (TSILs), 1-(3-sulfopropyl)caprolactam hydrogen sulfate, 1-(3-sulfopropyl)caprolactam p-toluene sulfonate, 1-(3-sulfopropyl)caprolactam phosphate sulfonate, 1-(3-sulfopropyl)ca-prolactam tetrafluoroborate, were prepared and characterized with low price caprolactam as raw material. The catalytic activities of these acidic ionic liquids were investigated by the esterification of acetic acid with ethanol and were compared with 3 kinds of SO3H-functionalized ionic liquids with different nitrogen heterocycles and concentrated sulfuric acid. The results showed that under the optimized conditions [n(C2H5OH):n(CH3COOH)=1:1.5], catalyst amount of 5% (w) based on acetic acid and ethanol., reaction temperature 80 ℃ and reaction time 6 h), the yield of ethyl acetate was up to 93.8%. The ionic liquids dried in vacuum till remained high activity after reused for 10 times, and the corrosion rates of the 316L austenitic stainless steel plates immersed in the systems with these ionic liquids were less than one sixth of that with sulfuric acid. Finally, the yields of series of ethyl esters were also high with [C3SO3HCP]HSO4 as catalyst, and the ionic liquids can form split-phases with ester product. Compared with the traditional sulfuric acid catalytic esterification, catalytic esterification of such ionic liquid has the advantages of low production cost, clean process, low corrosion rate, long useage cycle, and has the potential of replacing the traditional sulfuric acid in catalytic esterification reaction.

Key words: caprolactam, task-specific ionic liquids, esterification, catalytic activity