The worldwide production of cyclohexane is mainly carried out through the hydrogenation of benzene. Unreacted benzene is separated from produced cyclohexane, being one of the most challenging processes in the petrochemical industry due to their extremely close boiling points and the presence of an azeotrope. In this work, an experimental screening of seven ionic liquids has been done in order to check the suitability of the extractive distillation with ionic liquids. The vapor-liquid or vapor-liquid-liquid equilibria (VLE/VLLE) of {cyclohexane/benzene + ionic liquid} binary systems and {cyclohexane + benzene + ionic liquid} ternary systems have been determined by Headspace-Gas Chromatography technique. The Non-Random Two Liquids (NRTL) thermodynamic model has been used to fit the experimental VLE/VLLE accurately. Although all the selected ionic liquids enhanced the cyclohexane/benzene relative volatility (α_1,2) in comparison with conventional solvents, the [4bmpy][TCM] was chosen and implemented in Aspen Plus to simulate the extractive distillation process of benzene from cyclohexane with ionic liquids. The associated operating costs and the energy savings in comparison with conventional process, using N-methyl-2-pyrrolidone (NMP) as solvent, show that the extractive distillation with the [4bmpy][TCM] ionic liquid improves the conventional process, standing as an enhancer technology in the field.

环己烷的全球生产主要通过苯的加氢进行。未反应的苯从生产的环己烷中分离出来，这是石化行业最具挑战性的工艺之一，因为它们的沸点非常接近并且存在共沸物。在这项工作中，已经完成了对七种离子液体的实验筛选，以检查离子液体萃取蒸馏的适用性。{环己烷/苯+离子液体}二元体系和{环己烷+苯+离子液体}三元体系的汽-液或汽-液-液平衡（VLE / VLLE）已通过顶空-气相色谱技术确定。非随机两种液体（NRTL）热力学模型已用于精确拟合实验VLE / VLLE。α _1,2），其与常规溶剂相比，[4bmpy] [TCM]被选择和在Aspen Plus软件实现为从与离子液体环己烷模拟苯的萃取蒸馏方法。与使用N-甲基-2-吡咯烷酮（NMP）作为溶剂的常规方法相比，相关的运营成本和节能效果表明，使用[4bmpy] [TCM]离子液体进行萃取蒸馏可以改善常规方法，该领域的增强技术。