反气相色谱法表征离子液体1-乙基-3-甲基咪唑六氟磷酸盐的溶解度参数

摘要

采用反气相色谱法(IGC)表征了离子液体1-乙基-3-甲基咪唑六氟磷酸盐([EMIM]PF6)在343.15-373.15 K温度范围内的溶解度参数.各温度下溶解度参数分别为20.76(J/cm3)0.5(343.15 K),20.21(J/cm3)0.5(353.15 K),19.73(J/cm3)0.5(363.15 K),19.24(J/cm3)0.5(373.15 K).然后,通过外推法得到[EMIM]PF6在室温(298.15 K)时的溶解度参数为23.01(J/cm3)0.5.同时,测定了探针溶剂与[EMIM]PF6之间的质量分数活度系数、无限稀释活度系数和Flory-Huggins相互作用参数等热力学参数.结果表明,n-C6,n-C7,n-C8,n-C9和四氢呋喃为[EMIM]PF6的不良溶剂;而苯、甲苯、乙醇、甲醇、二氯甲烷、丙酮、乙酸乙酯、氯仿、乙醚、四氯化碳、乙酸甲酯和环己烷为[EMIM]PF6的良溶剂.%The solubility parameters of the ionic liquid(IL)1-ethyl-3-methylimidazolium hexafluorophosphate,[EMIM]PF6,were determined by inverse gas chromatography(IGC)at temperatures from 343. 15 to 373. 15 K. The solubility parameters of[EMIM] PF6 were calculated to be 20. 76(J/cm3)0.5(343. 15 K),20. 21(J/cm3)0.5(353. 15 K),19. 73(J/cm3)0.5(363. 15 K)and 19. 24 (J/cm3 )0. 5(373. 15 K),then the solubility parameter at room temperature(298. 15 K)was obtained to be 23. 01(J/cm3 )0. 5 by lin-ear extrapolation method. The thermodynamic parameters including weight fraction activity coefficient,activity coefficients at infinite dilution and Flory-Huggins interaction parameters between[EMIM]PF6 and the solvents were also determined. The results showed that the solvents including n-C6 ,n-C7 ,n-C8 ,n-C9 ,and tetrahydrofuran were the poor solvents for[EMIM]PF6 ,while benzene,tolu-ene,ethanol,carbinol,dichloromethane,acetone,ethyl acetate,chloroform,ether,tetrachloromethane,methyl acetate and cyclohexane were the favorite ones.