Separation of Carbon Dioxide by Potassium Carbonate based Supported Deep Eutectic Liquid Membranes: Influence of Hydrogen Bond Donor

This article focuses on the study of potassium carbonate (PC) based deep eutectic solvents based supported liquid membranes (DES-SLMs) for CO2 capture. A new class of green solvent was impregnated into microporous polyvinylidene fluoride (PVDF) membrane for the separation of CO2. Two types of DESs were synthesized by mixing and heating PC with glycerol or ethylene glycol separately. The novelty of this study lies in the exploitation of PC-DESs in the PVDF membrane. The mechanism of interaction was inferred from the spectral analysis (FTIR) whereas thermal analysis (TGA) was performed to analyze the stability of the prepared membrane. Experiments were performed to analyze the permeability and selectivity of the membranes. The results showed that PC-Glycerol based SLM exhibited permeability of 34.55 Barrer and ideal selectivity of 59.57 while PC-Ethylene Glycol based SLM exhibited permeability of 20.23 Barrer and ideal selectivity of 34.29 under similar operating conditions. Systematic analysis was made for some of the important operating parameters affecting the separation performance such as temperature and feed composition. Comparison was made between the performance of PC-DES-SLMs and conventional imidazolium based SILMs on the well-known Robeson’s upper bound plot. The current efforts of exploitation of PC-DES membrane will lead to new prospective for the efficient removal of CO2 from the industrial gas mixture.