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DOE OSTI · 2305724

Separating Xylene Isomers with a Calcium Metal–Organic Framework

Yu, Liang·Zhang, Jian·Ullah, Saif·Yao, Jinze·Luo, Haoyuan·Huang, Jiajin·Xia, Qibin·Thonhauser, Timo·Li, Jing·Wang, Hao
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Abstract

Here, the purification of p-xylene (pX) from its xylene isomers represents a challenging but important industrial process. Herein, we report the efficient separation of pX from its ortho- and meta- isomers by a microporous calcium-based metal–organic framework material (HIAM-203) with a flexible skeleton. At 30 °C, all three isomers are accommodated but the adsorption kinetics of o-xylene (oX) and m-xylene (mX) are substantially slower than that of pX, and at an elevated temperature of 120 °C, oX and mX are fully excluded while pX can be adsorbed. Multicomponent column breakthrough measurements and vapor-phase/liquid-phase adsorption experiments have demonstrated the capability of HIAM-203 for efficient separation of xylene isomers. Ab initio calculations have provided useful information for understanding the adsorption mechanism.

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Yu, Liang, Zhang, Jian, Ullah, Saif, Yao, Jinze, Luo, Haoyuan, Huang, Jiajin, Xia, Qibin, Thonhauser, Timo, Li, Jing, Wang, Hao. 2023-08-10. Separating Xylene Isomers with a Calcium Metal–Organic Framework. https://doi.org/10.1002/anie.202310672

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