A Triphasic Modulated Hydrothermal Approach for the Synthesis of Multivariate Metal-Organic Frameworks with Hydrophobic Moieties for Highly Efficient Moisture-Resistant CO2 Capture

作者：Hu, Zhigang; Gami, Abhishek; Wang, Yuxiang; Zhao, Dan^*

来源：Advanced Sustainable Systems, 2017, 1(11): 1700092.

DOI：10.1002/adsu.201700092

• breakthrough dynamics
• hydrophobic adsorbents
• modulated hydrothermal synthesis
• moisture-resistant CO2 capture
• multivariate metal-organic frameworks

The CO2 capture performance of metal-organic frameworks (MOFs) is largely compromised under wet conditions. This study reports a triphasic modulated hydrothermal approach to prepare multivariate (MTV) UiO-66(Zr) MOFs with hydrophobic moieties for wet CO2 capture under heterogeneous aqueous conditions. Among these MOFs, UiO-66(Zr)-NH2-F-4-0.53 shows a binary CO2 adsorption capacity of 0.76 mmol g(-1) and a CO2/N-2 (15/85) selectivity of 18.9 at 298 K, which is among the best of all UiO-66-type MOFs. Besides, UiO-66(Zr)-NH2-F-4-0.53 only loses 30% of its CO2 uptake capacity under wet (70% relative humidity) CO2/N-2 (15/85) mixture condition at 298 K, compared with almost 100% loss of zeolite materials and other hydrophilic adsorbents under similar conditions. This moisture-resistant feature makes UiO-66(Zr)-NH2-F-4-0.53 one of the best physisorption-based adsorbent materials for CO2 capture under wet conditions so far. Moreover, UiO-66( Zr)-NH2-F-4-0.53 demonstrates enhanced breakthrough dynamics with less cross-column pressure drop (Delta P = 0 bar) and 2.7 times larger mass transfer coefficient (k = 0.1235 s(-1)) than that of pristine UiO-66(Zr)-NH2 (Delta P = 0.25 bar, k = 0.0334 s(-1)). The present study offers new insights into the heterogeneous synthesis of MTV-MOFs and a paradigm to design hydrophobic MOFs with improved material features for moisture-resistant CO2 capture applications.

• 出版日期2017-11