Acta Phys. -Chim. Sin. ›› 2006, Vol. 22 ›› Issue (01): 71-75.doi: 10.3866/PKU.WHXB20060114

• ARTICLE • Previous Articles     Next Articles

Thermodynamic Properties of Ionic Liquid BMIAlCl4

TONG Jing; ZHANG Qing-guo; HONG Mei; YANG Jia-zhen   

  1. College of Chemistry, Liaoning University, Shenyang 110036, P. R. China; The Institute of Salt Lakes, Chinese Academy of Sciences, Xining 810008, P. R. China; Graduate School of the Chinese Academy of Sciences, Beijing 100049, P. R. China
  • Received:2005-06-01 Revised:2005-08-22 Published:2006-01-15
  • Contact: YANG Jia-zhen E-mail:jzyanglnu@yahoo.com.cn

Abstract: An ionic liquid (IL) has been prepared by directly mixing AlCl3 and 1-methyl-3-butylimidazolium chloride (BMIC) with molar ratio 1/1 under dry argon atmosphere. The densities and surface tensions of the pure IL were determined in the temperature range of (278.2±0.1) to (343.2±0.1) K. The properties for the ionic liquid were discussed in terms of Glasser′s empirical model. The values of volume of anion AlCl4- were obtained. The mean contribution of per methylene (CH2) group to standard entropy of the IL is 35.2 J•K-1•mol-1 and is in good agreement with contribution of 35.1 J•K-1•mol-1 from [Cn-min][NTf2]. The crystal energy of the IL is much lower than that of ionic solids, which is the main reason for the liquid state of the IL at room temperature. In addition, the interstice model was applied to calculate the thermal expansion coefficient of the IL, and the result agrees reasonably with the experimental value.

Key words: Ionic liquid, Density, Surface tension, AlCl3, Interstice model, Glasser′s theory