High p-xylene selectivity in aluminum-based metal–organic framework with 1-D channels

• Published in: Journal of industrial and engineering chemistry (Seoul, Korea) Vol. 117; pp. 333 - 341
• Main Authors: Bae, Hyun Jin, Kim, Seung-Ik, Choi, Yujin, Kim, Kyung-Min, Bae, Youn-Sang
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 25.01.2023; 한국공업화학회
• Subjects: Adsorption; Metal-organic framework (MOF); p-Xylene (pX); Simulated moving bed (SMB); Xylene isomer separation; 화학공학; Xylene isomer separation; Adsorption; Simulated moving bed (SMB); Metal-organic framework (MOF); p-Xylene (pX)
• ISSN: 1226-086X; 1876-794X
• DOI: 10.1016/j.jiec.2022.10.021

[Display omitted] •MIL-120(Al) showed high pX selectivity superior to reported values in MOFs and zeolites.•MIL-120(Al) exhibited good cyclic adsorption properties and excellent stabilities.•A dynamic simulation showed a potential of pX separation using a SMB with MIL-120(Al).•High pX selectivity can be attained within 1-D channels of approximately 7 Å. The separation of highly pure p-xylene (pX) from xylene isomers is an industrially important and challenging issue. Although simulated moving bed (SMB) processes using faujasite zeolites are currently used for pX separation, developing novel adsorbents with improved pX separation performances is strongly needed. In this study, an aluminum-based metal–organic framework (MOF), MIL-120(Al) with 1-D channels of approximately 7 Å, exhibited considerably high pX selectivities compared to xylene isomers (αpX/oX: ∼31; αpX/mX: ∼17; αpX/EB: ∼7.5; αpX/OME: ∼11), which are superior to reported values for other MOFs and zeolites under similar conditions. Such high selectivities may originate from the proper pore shape and size of MIL-120(Al). MIL-120(Al) also showed good cyclic adsorption properties as well as superior hydrothermal and chemical stabilities. Finally, a dynamic simulation showed that MIL-120(Al) could achieve approximately complete separation of pX from a xylene isomer mixture using an SMB process.