CFD Simulation of CO2 Capture in a Microchannel by Aqueous Mixtures of MEA and [Bmim]BF4 Modified with TiO2 Nanoparticles

Abstract

In this research, a novel aqueous solvent, i.e., nanoparticle-enhanced ionic liquid (NEIL), is proposed for CO 2 capture by mixing of MEA as the base fluid and [Bmim]BF 4 ionic liquid and TiO 2 nanoparticles as chemical additives. Then, the flow hydrodynamics, mass transfer characteristics, and CO 2 absorption performance of the proposed solvent are investigated in a T-shaped microchannel structure by Computational Fluid Dynamics technique at steady-state condition. To present a detailed model, the Navier–Stokes and continuity equations are combined with a two-phase laminar flow module considering mass transfer between heterogeneous phases. Then, the effects of [Bmim]BF 4 and TiO 2 mass fraction on CO 2 loading, bubble formation, and velocity profile are investigated at different gas and liquid holdups at ionic liquid fraction 0 % to 10% and nanoparticle fraction 0 to 0.1%. It concludes that the purification fraction reaches a maximum at TiO 2 weight fraction 0.04% and applying solvent with high nanoparticle content decreases purification fraction. In general, the proposed solvent and the considered contactor present adequate performance to absorb CO 2 from the gas mixture.