CO2 capture enhancement by encapsulation of nanoparticles in metal–organic frameworks suspended in physical absorbents
Ronghuan Xu, Hyungseop Ahn, Seonggon Kim, Jae Won Lee, Yong Tae Kang
Abstract
In this study, CO2 nanoabsorbents composed of encapsulated Fe3O4 nanoparticles in metal-organic frameworks (MOFs) and methanol, are developed to overcome the limitations of conventional CO2 sorbents. The polyvinylpyrrolidone-functionalized Fe3O4 nanoparticles encapsulated in (Zn)MOF-74 [Zn2(DOBDC), DOBDC = 2, 5-dihydroxyterephthalic acid] are dispersed in the methanol. Compared with pure methanol, CO2 absorption and regeneration performances of Fe3O4 @ (Zn)MOF-74/methanol are improved by 13.07% and 16.25% (Abs.: 0.84 g-CO2/L-solvent and reg.: 0.77 g-CO2/L-solvent), respectively, at optimum conditions of 0.01 wt%. Cyclic stability experiments exhibit that the performance of Fe3O4 @ (Zn)MOF-74/methanol can preserve 93.76% of their initial capacities. It is finally concluded that the absorption performance is improved by hydrodynamic and shuttle effects while the CO2 sorbent regeneration performance is enhanced by metal-organic heat carriers (MOHCs) and nucleation from the surface of nanoparticles by introducing Fe3O4 @ (Zn)MOF-74 nanoparticles.