Water Effects on Postcombustion CO2 Capture in Mg-MOF-74

详细信息    查看全文

• 作者：Jiamei Yu ; Perla B. Balbuena
• 刊名：The Journal of Physical Chemistry C
• 出版年：2013
• 出版时间：February 21, 2013
• 年：2013
• 卷：117
• 期：7
• 页码：3383-3388
• 全文大小：337K
• 年卷期：v.117,no.7(February 21, 2013)
• ISSN：1932-7455

文摘

Mg-MOF-74, one of the best metal鈥搊rganic framework (MOF) materials for CO₂ adsorption and separation, has been widely explored in CO₂ capture. In this work, water effects on postcombustion CO₂ capture in Mg-MOF-74 are evaluated by using a combination of Grand Canonical Monte Carlo and density functional theory (DFT) simulations. Our results show that in this MOF the CO₂ adsorption capacity is decreased by the presence of water molecules linked to coordinatively unsaturated metal sites (CUMs). This effect is a consequence of the reduction of binding energy between CO₂ and the water-coordinated Mg-MOF-74 framework. DFT calculations indicate that such binding energy is much lower than that without coordinated water. More importantly, we find that the difference of the binding energy between CO₂ and CUM in a MOF and that between CO₂ and CUM-coordinated water are good descriptors to evaluate water effects on CO₂ capture in MOFs with CUMs. At the same time, these investigations further demonstrate that the CUMs in MOFs play an important role in their performance for CO₂ capture from a practical stream containing water and other impurities.