(687e) Regenerable Mesoporous MgO Calcined from Metal Organic Frameworks (MOFs) for CO2 Capture

Carbon capture and storage (CCS) technology has been gaining more attention due to the considerable correlation between the increasing concentration of atmospheric carbon dioxide and global climate changes.^1,2 Among many potential methods and materials for CO₂ Capture, alkaline earth-based oxide materials such as calcium oxides and magnesium oxides have been positioned as one of the promising solid adsorbent materials owing to their advantages such as wide availability of precursors in nature, high adsorption capacity, low cost and low toxicity.^3,4 Specially, magnesium oxides have been widely studied mainly because of their lower energy requirement for regeneration compared to calcium oxides.³ However, magnesium oxides that have been made from conventional precursors including magnesium hydroxide, magnesium carbonate, magnesium oxalate⁵, magnesium acetate tetrahydrate⁶, magnesium nitrate hexahydrate⁷ and magnesium chloride hexahydrate⁸, are suffering from large CO₂ adsorption capacity loss over multiple adsorption/desorption cycles, mainly because of the sintering of oxide particles.

Here we present the synthesis of magnesium oxide nanoparticles created via thermal decomposition of metal organic frameworks (MOFs)^9,10, which demonstrates improved regenerability in recurring CO₂ adsorption processes. In this case, a magnesium containing MOF is first synthesized via solvothermal process as the precursor, followed by calcination under air atmospheres to generate magnesium oxide nanoparticles. Characterization techniques such as X-ray diffraction, SEM, TEM, EDX, IR and BET surface area analysis were applied to obtain the structural and elemental information of magnesium oxide nanoparticles, while their CO₂ adsorption characteristics were analyzed using TGA. The results show that the magnesium oxide nanoparticles in this work have high surface area and CO₂ adsorption capacities. Most importantly, magnesium oxides in this work exhibit enhanced regenerability compared to those made from conventional precursors^7,8. More details about the impacts of different calcination conditions like temperatures and heating rates onto CO₂ adsorption capacities and regenerability, as well as the explanations for good regenerability will be discussed.

References:

[1] C. F. Cogswell, H. Jiang, J. Ramberger, D. Accetta, R. J. Willey, and S. Choi, Langmuir, 2015, 31, 4534−4541.

[2] D. Andirova, C. F. Cogswell, Y. Lei, S. Choi, Micropor. Mesopor. Mat., 2016, 219, 276–305.

[3] S. Choi, J. H. Drese and C. W. Jones, ChemSusChem, 2009, 2, 796–854.

[4] S. Lee and S. Park, J. Ind. Eng. Chem., 2015, 23, 1–11

[5] G. Song, X. Zhu, R. Chen, Q. Liao, Y.-D. Ding and L. Chen, RSC Adv., 2016, 6, 19069–19077

[6] G. Song, Y.-D. Ding, X. Zhu and Q. Liao, Colloids Surf., A, 2015, 470, 39–45

[7] A. Hanif, S. Dasgupta and A. Nanoti, Ind. Eng. Chem. Res., 2016, 55, 8070−8078

[8] A. M. Ruminski, K.-J. Jeon and J. J. Urban, J. Mater. Chem., 2011, 21, 11486–11491

[9] R. Das, P. Pachfule, R. Banerjee and P. Poddar, Nanoscale, 2012, 4, 591–599

[10] T. K. Kim, K. J. Lee, J. Y. Cheon, J. H. Lee, S. H. Joo and H. R. Moon, J. Am. Chem. Soc. 2013, 135, 8940−8946