双阳离子型离子液体C3(MIM)2PF62的热容测定及估算

摘要

利用差示扫描热量计(DSC)测定了双阳离子型离子液体1,1′-(丙烷-1,3-二基)-双(3-甲基-1H-咪唑鎓-1-基)双六氟磷酸盐([C3(MIM)2][PF6]2)在293.15-543.15 K温区内的摩尔热容.实验结果表明:在293.15-403.15 K和433.15-543.15 K温区内,该化合物无相变及其他热异常现象发生,将实验数据拟合得到了该化合物热容随温度变化的多项式方程.其熔化温度、熔化焓及熔化熵分别为416.83 K,38.256 kJ/mol和91.778 J/(K·mol).由热容数据计算出其在固相区和液相区相对于标准参考温度298.15 K的热力学函数值.采用基团贡献法对433.15-543.15 K温区的热容进行了估算,为该离子液体的工业应用提供了热力学基础数据.%The molar heat capacity of dicationic ionic liquid 1, 1'-( propane-1, 3-diyl)-bis (3-methyl-1Himidazolium-1-yl) dihexafluorophosphate ( [C3 ( MIM )2][PF6]2 ) was measured with differential scanning calorimeter(DSC) at 293.15-543.15 K.The results show that no phase transition or other thermal anomaly is observed in the range of 293.15-403.15 K and 433.15-543.15 K, in which the molar heat capacities are fitted to polynomials.The fusing temperature, molar enthalpy and entropy of fusion are 416.83 K, 38.256 kJ/mol and 91.778 J/(K· mol), respectively.The thermodynamic functions relative to the standard reference temperature 298.15 K were derived based on the heat capacity data.A group contribution method was used to calculate its molar heat capacity from 433.15 to 543.15 K.The basic data are helpful for its industrial application.