(653g) CO2 Capture in Uio-66-Type Metal-Organic Frameworks (MOFs)

Dan Zhao*

Department of Chemical and Biomolecular Engineering,

National University of Singapore, 117585 Singapore

E-mail: chezhao@nus.edu.sg

The large-scale anthropogenic carbon dioxide (CO₂) emission has aroused world-wild concerns. One of the key steps in carbon mitigation is CO₂ capture from stationary CO₂ emission resources. Metal-organic frameworks (MOFs) are coordination polymers consisting of metal ions or clusters as nodes and organic ligands as spacers. The study of CO₂ capture using MOFs as adsorbents is booming because of their ultra-high surface area, uniform yet tunable pore size, and versatile chemical compositions. However, several issues still exist preventing their large scale applications, such as selectivity, stability, and material cost. In our research, we aim at circumventing the above problems through rational ligand design and crystal engineering based on UiO-66-type MOFs, with the emphases on a) mitigating moisture interference, b) increasing CO₂ selectivity, c) strengthening materials stability, and d) reducing material cost. The synthesized MOF candidates have underwent various tests for their eligibility in CO₂ capture, such as stability, gas sorption, and breakthrough tests. We have identified several promising MOF candidates with the CO₂ capture performance equivalent or even better than the industrial benchmark material zeolite 13X. These materials will be integrated into the next-level process and system research.

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