Acta Chimica Sinica ›› 2012, Vol. 70 ›› Issue (06): 770-774.DOI: 10.6023/A1108223 Previous Articles     Next Articles

Special Topic


陈学伟, 宋红兵, 陈鹏, 王芙蓉, 钱宇, 李雪辉   

  1. 华南理工大学化学与化工学院 制浆造纸工程国家重点实验室 广州 510640
  • 投稿日期:2011-08-25 修回日期:2011-12-02 发布日期:2012-02-14
  • 通讯作者: 李雪辉
  • 基金资助:

    国家自然科学基金(Nos. 20876055, 20906029)资助项目.

Studying of the Basicity of Ionic Liquids by Potentiometric Titration

Chen Xuewei, Song Hongbing, Chen Peng, Wang Furong, Qian Yu, Li Xuehui   

  1. School of Chemistry and Chemical Engineering, State Key Laboratory of Pulp & Paper Engineering, South China University of Technology, Guangzhou 510640
  • Received:2011-08-25 Revised:2011-12-02 Published:2012-02-14
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Nos. 20876055, 20906029).

Design, synthesis and application of basic ionic liquids have attracted much extensive interest in recent years. The determination of the basic strength is of crucial significance for the utilization of basic ionic liquids. However, studies on the basicity characterization were rarely reported for basic ionic liquids to the best of our knowledge. In this paper, the acid-dissociation constant pKb values of a series of basic ionic liquids synthesized were determined by potentiometric titration method. Then, the basicity of these ionic liquids was characterized by comparison of their pKb values. Finally, the relationship between the basicity and structure of these ionic liquids was discussed. The results show that the basicity of carboxylate ionic liquids is determined mainly by their anions, whereas the different cation is able to have its basicity finely tuned. The results also show that the basicity of amino-functionalized imidazolium ionic liquid is weaker than that of triethylamine due to the strong electron withdrawing effect of the positively charged imidazolium ring.

Key words: basic ionic liquids, basic strength, potentiometric titration, pKb, basicity-structure relation