Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore 117585, Singapore.
Department of Materials Science and Engineering, National University of Singapore, Singapore 117575, Singapore.
J Am Chem Soc. 2023 May 31;145(21):11643-11649. doi: 10.1021/jacs.3c01705. Epub 2023 May 17.
Exclusive capture of carbon dioxide (CO) from hydrocarbons via adsorptive separation is an important technology in the petrochemical industry, especially for acetylene (CH) production. However, the physicochemical similarities between CO and CH hamper the development of CO-preferential sorbents, and CO is mainly discerned via C recognition with low efficiency. Here, we report that the ultramicroporous material Al(HCOO), ALF, can exclusively capture CO from hydrocarbon mixtures, including those containing CH and CH. ALF shows a remarkable CO capacity of 86.2 cm g and record-high CO/CH and CO/CH uptake ratios. The inverse CO/CH separation and exclusive CO capture performance from hydrocarbons are validated via adsorption isotherms and dynamic breakthrough experiments. Notably, the hydrogen-confined pore cavities with appropriate dimensional size provide an ideal pore chemistry to specifically match CO via a hydrogen bonding mechanism, with all hydrocarbons rejected. This molecular recognition mechanism is unveiled by in situ Fourier-transform infrared spectroscopy, X-ray diffraction studies, and molecular simulations.
通过吸附分离从烃类物质中选择性捕获二氧化碳（CO）是石化行业的一项重要技术，特别是在乙炔（CH）生产中。然而，CO 和 CH 在物理化学性质上的相似性阻碍了 CO 优先吸附剂的发展，并且 CO 主要通过低效率的 C 识别来区分。在这里，我们报告了超微孔材料 Al(HCOO)3，ALF，可以从烃类混合物中选择性捕获 CO，包括含有 CH 和 CH 的混合物。ALF 表现出出色的 CO 容量为 86.2 cm³/g，以及创纪录的 CO/CH 和 CO/CH 吸附比。通过吸附等温线和动态穿透实验验证了从烃类物质中进行逆 CO/CH 分离和选择性 CO 捕获的性能。值得注意的是，具有适当尺寸的受限氢孔腔提供了一种理想的孔化学，通过氢键机制特异性地与 CO 匹配，而排斥所有烃类物质。这种分子识别机制通过原位傅里叶变换红外光谱、X 射线衍射研究和分子模拟揭示出来。
