基于COSMO-SAC模型的分子筛选方法用于咪唑类离子液体吸收甲苯蒸气

采用基于COSMO-SAC模型的分子筛选方法，对作为甲苯蒸气吸收剂的咪唑类离子液体进行了筛选。建立了100种常见的N，N'-二烷基咪唑阳离子与阴离子构成的咪唑类离子液体的s-谱图，在此基础上计算了303.15 K下离子液体对甲苯的吸收势，并以此为热力学评价标准对吸收剂进行筛选。选取6种离子液体进行甲苯蒸气的吸收实验，通过其饱和吸收量验证此方法的可行性。研究表明，实验和分子筛选结果相吻合。利用Gaussian 09软件进行微观结构分析，计算了离子液体阳离子与甲苯的相互作用能。对进气浓度和进气速度等动力学因素的影响进行探究，在条件为303.15 K、进气浓度为10000 mg·m^-3、进气速度为0.05 m³·h^-1情况下，离子液体对甲苯的初始吸收率高达96.2%。此外，实验验证了离子液体随着重复利用次数的增加，其吸收效果基本不变。

COSMO-SAC molecular screening method to analyze imidazole ionic liquids for toluene vapor absorption

Imidazolium ionic liquids as toluene vapor absorbent were evaluated by a molecular screening method based on the COSMO-SAC model. A s-map was established for hundred common imidazolium ionic liquids composed of N,N'-dialkylimidazolium cation and an anion. Absorption potential of ionic liquids to toluene vapor at 303.15 K was calculated from the s-map and was used as thermodynamic evaluation criterion to screen absorbents. Experimental measurements on saturated absorption of toluene vapor in six ionic liquids showed consistent results with these of molecular screening, which verified reliability of this molecular screening method. Interaction energy of ionic liquid cation and toluene was calculated by Gaussian 09 software. Subsequently, effects of kinetic factors such as vapor inlet concentration and velocity were explored. An initial toluene absorption by ionic liquid reached to 96.2% under temperature of 303.15 K, inlet concentration of 10000 mg·m^-3, and inlet velocity of 0.05 m³·h^-1. Further study indicated that toluene absorption was almost not changed with increasing number of repeated use cycles of ionic liquid absorbents.