Ionic Liquids for Capturing 1,2-Dimethoxyethane (DMET) in VOCs: Experiment and Mechanism Exploration
Chengmin Gui, Guoxuan Li, Ruisong Zhu, Qinghua Liu, Zhigang Lei
Abstract
Ionic liquids (ILs) as green solvents were first used to capture 1,2-dimethoxyethane (DMET) from exhaust gas. The vapor liquid equilibrium (VLE) data of [EMIM][TF2N] + DMET and triethylene glycol (TEG) + DMET were measured. The results showed that the popular UNIFAC-Lei model is in good agreement with experimental data. The gas absorption experiment with [EMIM][TF2N] as absorbent was conducted. It demonstrates that the IL has good separation performance for capturing DMET, the absorption ratio being 87.32%. Then, the absorption capacities of 45 ILs for DMET were calculated by COSMO-RS model, while DMET removal mechanism was explored by σ-profiles analysis and molecular dynamics (MD) simulation. Finally, industrial scale process simulation using [EMIM][TF2N] and TEG as absorbents to capture DMET was made. Compared to the benchmark TEG process, the total operating cost and the total annual cost (TAC) in the IL process decrease by 24.06% and 17.15%, respectively. This further proves that ILs have great application potential for the condensable volatile organic compounds (VOCs) capture, especially in energy saving and improving economic benefits.