Experimental and Simulation Studies on the Capture of Chlorinated Volatile Organic Compounds by Ionic Liquids

Abstract

The hydrophilic ionic liquid (IL) [EMIM][BF 4 ] was adopted to absorb two chlorinated volatile organic compounds (CVOCs), named 1,2dichloroethane and 1,1,2-trichloroethane. First, [EMIM][BF 4 ] was screened out as the optimal absorbent from 69 IL candidates by the COSMO-RS model. Then, CVOC absorption experiments were conducted usingshows the highest absorption rate for both 1,2dichloroethane (95.81%) and 1,1,2-trichloroethane (84.91%). Quantum chemical calculations show that both strong intermolecular electrostatic interaction and van der Waals interaction promote the absorption of CVOCs by [EMIM][BF 4 ]. Subsequently, industrial-scale CVOC capture processes, simulation and optimization, were carried out with [EMIM][BF 4 ] and TEG as absorbents, to attain the goal of reducing the concentration of CVOCs in the gas stream to 500 ppm (in mole fraction). The result shows that [EMIM][BF 4 ] has a higher processing capacity and a lower heat duty under optimal operating conditions.

Ionic-Liquid-Assisted Capture of Volatile Low-Carbon Alcohols in Printing Plant Exhaust Gas

“…σ-Profile can reveal the interaction mechanism of ILs with target substances at the molecular level through the polar charge density distribution on the molecular surface and is considered a mathematical description of molecular polarity. 38 The σ-profile is mainly classified into three regions: the hydrogen bond donor (HBD) region, the hydrogen bond acceptor (HBA) region, and the nonpolar (NP) region. The molecular fragments with negatively polarized charge densities show positive σ values, and those with positively polarized charge densities show negative σ values.…”