Novel non-aqueous MEA solutions for CO2 capture

Abstract

Present obstacles for CO2 capture involve reducing capital and energy costs. This study describes carbon dioxide capture with monoethanolamine (MEA) in organic solvents as a way to reduce the energy consumption during desorption. The solvents used in this study are a mixture of ethylene glycol and 1-propanol (EG/PrOH), diethylene glycol monoethyl ether (DEGMEE), and N-methylformamide (NMF). A microwave regeneration technique was used to easily and quickly screen the performances of the amine solutions and experiments were designed to investigate the solvent effects on CO2 capture by MEA. Globally, DEGMEE solutions resulted in the lowest energy consumptions and good CO2 cyclic capacities; the best solutions reducing the energy consumption by 78% in comparison to the traditional 30 wt% MEA aqueous solution. These findings show that organic solvents have much promise in improving CO2 capture technology. It was also found that using NMF greatly enhanced the CO2 absorption kinetics but was detrimental during the desorption step.