On the role of solid particles in CO2 bubble nucleation for solvent regeneration of MEA-based CO2 capture technology

Monoethanolamine (MEA) solution has been used widely in the post-combustion CO 2 capture process; however, the high heat duty and reaction temperature (e.g. 125°C) for MEA regeneration leads to a high energy requirement (nearly 70–80% of the total running cost). We report the use of solid particles (H-Zeolite Socony Mobile-5 (HZSM-5), quartz, and activated carbon) to facilitate the mass transfer of CO 2 bubble nucleation and enhance the CO 2 desorption rate. The results show that the mass transfer of CO 2 from liquid phase to gas phase is the rate-determining step, rather than the chemical reaction. The addition of HZSM-5 particles in the solution significantly enhanced CO 2 bubble nucleation by providing nucleation sites and gas cavities, leading to an average CO 2 desorption rate enhancement of 43.2%, and an energy consumption reduction of 23.3%. This process also operated at ∼95°C, which is a much lower temperature than that used in the commercial process and is feasible for industrial applications. © 2019 Society of Chemical Industry and John Wiley & Sons, Ltd.