Regeneration of CO₂‐rich aqueous amine‐ionic liquid blends in CO₂ capture process

Abstract

In this present work, solvent regeneration of CO2‐rich aqueous solvent blends containing Monoethanolamine (MEA) and Ionic liquids was studied experimentally. The ionic liquids (ILs) used are tetrabutylammonium acetate [TBA][OAC] and tetrabutylammonium bromide [TBA][Br]. The solvent mixture composition of ILs are 2, 5, 10 wt% and their respective MEA as 28, 25, 20 wt%. CO2 absorption and desorption process were performed using solvent blends. The recovery of solvent was performed for three different temperatures 358, 368 and 373 K. The findings reveal that solvent blends of MEA with [TBA][Br] exhibit higher regeneration efficiency and lower regeneration energy than MEA with [TBA][OAC] blends with a minimum composition of 2 wt% [TBA][Br]. Energy consumption for recovery of 2 wt% [TBA][Br] blend with 28 wt% MEA was found to be 65.66 KJ mole−1 of CO2 which is 41.97% less than 30 wt% MEA. Furthermore, physicochemical properties such as pH, density, viscosity, carbon loading and surface tension have been measured before and after CO2 absorption and desorption process. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd.