物理化学学报 >> 2012, Vol. 28 >> Issue (11): 2558-2566.doi: 10.3866/PKU.WHXB201208271

热力学,动力学和结构化学 上一篇    下一篇

甲醇对1-丁基-3-甲基咪唑四氟硼酸离子液体结构与性质影响的模拟研究

王丁, 田国才   

  1. 昆明理工大学冶金与能源工程学院, 昆明 650093
  • 收稿日期:2012-06-12 修回日期:2012-08-24 发布日期:2012-10-17
  • 通讯作者: 田国才 E-mail:tiangc01@gmail.com
  • 基金资助:

    国家自然科学基金(50904301, 51264021); 云南省中青年学术技术带头人后备人才(2011CI013)和云南省自然科学基金(2008E0049M)资助项目

Simulation Study of the Effect ofMethanol on the Structure and Properties of 1-Butyl-3-methylimidazolium Tetrafluoroborate Ionic Liquid

WANG Ding, TIAN Guo-Cai   

  1. Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, P. R. China
  • Received:2012-06-12 Revised:2012-08-24 Published:2012-10-17
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (50904031, 51264021), Back-up Personnel Foundation of Academic and Technology Leaders of Yunnan Province, China (2011CI013), and Natural Science Foundation of Yunnan Province, China (2008E0049M).

摘要:

采用分子动力学模拟方法研究了298.15 K、0.1 MPa下摩尔分数为0.1-0.9 的甲醇对1-丁基-3-甲基咪唑四氟硼酸盐([BMIM][BF4])结构与性质的影响. 获得了体系的密度、径向分布函数、配位数、自扩散系数、粘度和电导率, 模拟得到的密度值与实验值符合较好. 结果显示: 体系各组分之间的径向分布函数随甲醇摩尔分数的增加呈规律性变化; 体系内阴阳离子的自扩散系数随着甲醇摩尔分数的增加不断增大; 甲醇的加入削弱了阴阳离子之间的相互作用, 体系粘度随着甲醇摩尔分数的增加逐渐减小, 电导率不断增大. 分析空间分布函数得到体系中各组分的三维空间分布情况.

关键词: 离子液体, 1-丁基-3-甲基咪唑四氟硼酸盐, 甲醇, 分子动力学模拟, 微观结构, 物理化学性质

Abstract:

The microstructure and properties of 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM] [BF4])/methanol mixtures with different amount-of-substance fractions for methanol (0.1-0.9) were studied by molecular dynamics (MD) simulations at 298.15 K and 0.1 MPa. The densities, radial distribution functions, coordination numbers, self-diffusion coefficients, viscosities, and conductivities of the systems were obtained. The simulated densities agreed with experimental values. As the methanol amount-ofsubstance fraction increased, the radial distribution functions of different components in the mixture showed regular changes, the interaction between the anion and cation and the viscosity decreased, and the conductivity and the self-diffusion coefficients increased. The spatial distribution functions obtained from the MD simulations were visualized to depict the microscopic structures of different components in the system.

Key words: Ionic liquid, 1-Butyl-3-methylimidazolium tetrafluoroborate, Methanol, Molecular dynamics simulation, Microstructure, Physicochemical property