Efficient separation of xylene isomers by a guest-responsive metal–organic framework with rotational anionic sites
Abstract The separation of xylene isomers ( para -, meta -, orth -) remains a great challenge in the petrochemical industry due to their similar molecular structure and physical properties. Porous materials with sensitive nanospace and selective binding sites for discriminating the subtle structural...
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Published in | Nature communications Vol. 11; no. 1; p. 5456 |
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Main Authors | , , , , , , , , , , |
Format | Journal Article |
Language | English |
Published |
London
Nature Publishing Group
28.10.2020
Nature Publishing Group UK Nature Portfolio |
Subjects | |
Online Access | Get full text |
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Summary: | Abstract
The separation of xylene isomers (
para
-,
meta
-,
orth
-) remains a great challenge in the petrochemical industry due to their similar molecular structure and physical properties. Porous materials with sensitive nanospace and selective binding sites for discriminating the subtle structural difference of isomers are urgently needed. Here, we demonstrate the adaptively molecular discrimination of xylene isomers by employing a NbOF
5
2−
-pillared metal–organic framework (NbOFFIVE-bpy-Ni, also referred to as ZU-61) with rotational anionic sites. Single crystal X-ray diffraction studies indicate that ZU-61 with guest-responsive nanospace/sites can adapt the shape of specific isomers through geometric deformation and/or the rotation of fluorine atoms in anionic sites, thereby enabling ZU-61 to effectively differentiate xylene isomers through multiple C–H···F interactions. ZU-61 exhibited both high
meta
-xylene uptake capacity (3.4 mmol g
−1
) and
meta
-xylene/
para
-xylene separation selectivity (2.9, obtained from breakthrough curves), as well as a favorable separation sequence as confirmed by breakthrough experiments:
para
-xylene elute first with high-purity (≥99.9%), then
meta
-xylene, and
orth
-xylene. Such a remarkable performance of ZU-61 can be attributed to the type anionic binding sites together with its guest-response properties. |
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Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 2041-1723 2041-1723 |
DOI: | 10.1038/s41467-020-19209-7 |