常压下新型季铵离子液体密度-温度特性及关联

On the temperature dependence of novel quaternayry ammonium ionic liquids at atmospheric pressure

采用振动管密度计测定了常压下[(CH3CH2)2NH2][HSO4]和[(CH3CH2)3NH][HSO4]两种离子液体在熔点以上温度时,每相间0.5℃的密度数据.系统温度的控制精度为±0.01℃,密度的测量精度为±1×10-5g.cm-3.利用测量密度与对应温度的实验数据,用最小二乘法拟合2种不同的密度方程,给出了密度-温度函数的对应参数.对比得出密度与温度间的适宜函数关系,与实验数据吻合较好.用适宜函数计算[(CH3CH2)2NH2][HSO4]和[(CH3CH2)3NH][HSO4]的密度的平均绝对偏差、最大绝对偏差分别为0.003%、0.001%和0.008%、0.02%,可为离子液体在工程应用中提供基础数据.

The densities of [ （ CH3 CH2 ） 2 NH2 ] [ HSO4 ] and [ （ CH3 CH2 ） 3 NH ] [ HSO4 ] were measured over a temperature rang of melting piont, almost every 0.5℃ with vibrating tube densimeter. The precision of the temperature is 0.01 ℃ and the density is ± 1 × 10^-5 g . cm^-3 At the same time, the dependences of densities on temperatures are expressed with two different density functions by least square nonlinear fitting, and the parameters of the density functions are reported. The better density function is given after the comparison among the two functions, The regressed formulas have good accordance with the experimental data. The average absolute deviation and the maximum absolute deviation of the density measurements from the correlation for two ionic liquids [ （ CH3 CH2 ）2 NH2 ] [ HSO4 ] and [ （ CH3 CH2 ）3 NH ] [ HSO4 ] were 0. 003 % ,0.001% and 0. 008% ,0.02 %, respectively.