INORGANIC CHEMISTRY
·
2024
·
IF 4.3
Jing-ran Yu,Pan-pan Zhang,Jia-yu Ding,Yue-bin Liu,Wei-hai Lin,Wei Shao,Jia-jia He,Qihan Gong,Ming Xue
The separation of high-octane dibranched alkanes from naphtha is critical in the refining of gasoline. To date, research on the membrane-based separation of alkane isomers has been limited, with a particular paucity of investigations into mixed-matrix membranes. Herein, the continuous and dense UiO-66/PIM-1 mixed-matrix membrane, which was prepared through precise control of the interfacial structure, was first applied to the differentiation of C6 alkane isomers. Due to the synergistic combination of UiO-66 with differential adsorption capabilities for alkanes and PIM-1 that possesses a cross-linkable structure, the resulting UiO-66/PIM-1-(20) membrane demonstrated remarkable separation performance and high stability. Pervaporation measurements showed that the mass fraction of 2,2-dimethylbutane in the feed side was increased from 50.0 to 75.8 wt % while an excellent flux of 1700 g m–2 h–1 was maintained over a continuous 40 h period. The UiO-66/PIM-1-(20) membrane, characterized by its facile replication and processing, shows potential for large-scale fabrication. This study offers a new approach to the membrane separation of alkane isomers.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2024
·
IF 3.2
Le Chen,An Xie,Nan Zhang,Jianjun Yin,Qun Chen,Mingyang He,Zhihui Zhang
Zeolitic-Imidazolate Framework 8 (ZIF-8), a porous crystalline absorbent, could be synthesized from the coordination reaction of zinc ions and 2-methylimidazole (2-mIM). ZIF-8 has a large specific surface area and a high adsorption capacity for n -hexane ( n HEX). However, ZIF-8 suffers from low selectivity for both linear and mono-chain alkanes. Therefore, ZIF-8 was modified through 2-mIM ligand being partly replaced by 2-nitroimidazole (2-nIM) through Vapor-Phase post-synthesis modification. The modified materials were denoted as ZIF-8-2-nIM-X (X = 24h, 48h, 72h). ZIF-8-2-nIM-X has a higher specific surface area and better thermal stability than ZIF-8. Further thermodynamic and kinetic calculations show that the affinity of hexane isomers on ZIF-8-2-nIM-X is spontaneous physical adsorption combined with an exothermic process. In contrast, kinetic studies show that the adsorption of hexane isomers on ZIF-8-2-nIM-X is a pseudo-second-order kinetic model. The batch and dynamic adsorption and separation properties of ZIF-8-2-nIM-X for hexane isomers were studied. The results of the one-component vapor adsorption equilibrium experiment show that ZIF-8-2-nIM-72h has the best adsorption separation coefficient at 293 K. The adsorption capacity of n HEX and 3-methylpentane (3MP) were 211.63 mg/g and 33.91 mg/g, respectively. Compared with ZIF-8 (selectivity coefficient: 1.08), the adsorption selectivity coefficient of the modified material is greatly improved. The adsorption selectivity coefficient of n HEX/3MP is 6.24 (ZIF-8-2-nIM-72h).
研究领域:
材料科学
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Jiayan Zhu,Lin Zhang,Zongjian Liu,Wenxia Zhai,Zhengfei Ma,Qun Cui,Haiyan Wang
The separation of mono- and di-branched C6 alkane isomers is one of the most challenging industrial processes for the production of high-octane gasoline components. In this work, ZIF-8 with dual ligands of imidazole (IM) and 2-methylimidazole (2-MIM), named as DLA-ZIF-8-IM, was synthesized by the method of delayed linker addition, and the microstructure of DLA-ZIF-8-IM was analyzed. Adsorption thermodynamic, kinetic and separation properties of C6 alkane isomers were investigated. The results show that compared with SALE-ZIF-8-IM prepared by the solvent-assisted ligand exchange method, the synthesis method of DLA-ZIF-8-IM is simpler and the BET specific surface area and pore volume (2136 m 2 ·g −1 and 0.72 cm 3 ·g −1 ) of DLA-ZIF-8-IM are increased by 21 % and 14 %, which is more conducive to adsorption and diffusion of 3-methylpentane (3MP) on DLA-ZIF-8-IM. The equilibrium adsorption capacity of 3MP on DLA-ZIF-8-IM reaches up to 2.89 mmol·g −1 , which is 1.1 times than that on SALE-ZIF-8-IM, and the ratio of diffusion time constants between 3MP and 2,3-dimethylbutane (23DMB) on DLA-ZIF-8-IM (5.13) is 2.2 times than that on SALE-ZIF-8-IM. Moreover, at 30℃, the breakthrough adsorption capacity of 3MP on DLA-ZIF-8-IM is 1.46 mmol·g −1 , which is 1.6 times more than that of SALE-ZIF-8-IM (0.90 mmol·g −1 ), while the breakthrough adsorption capacity of 23DMB is basically the same. The separation factor between 3MP and 23DMB on DLA-ZIF-8-IM is 2.96 via the synergy of thermodynamic and kinetic mechanism and the dynamic adsorption capacity of 3MP reaches 1.46 mmol·g −1 . DLA-ZIF-8-IM achieves complete separation of C6 alkane mixtures for obtaining single high-purity product. This work provides a novel synthesis strategy for developing C6 alkane (clear) adsorption separation materials by modulating microporous structures of dual-ligand MOFs.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Xianjie Wang,Yaning Zhao,Hengsheng Wei,Yi Wang,Jingdong Gou,Jinhui He,Xue Ma,Louwei Cui,Liuyi Pan,Jiaojiao Liu,Dong Li
The separation of coal-derived C8 cyclohexane isomers, particularly cis-1,3-dimethylcyclohexane (cis-1,3-DMCH) and ethylcyclohexane (ECH), remains challenging due to their similar molecular structures and physicochemical properties, while research on cycloalkane isomer separation is limited. A series of functionalized UiO-66 derivatives (UiO-66, UiO-66-(CH 3 ) 2 , UiO-66-OH, and UiO-66-NO 2 ) were synthesized via solvothermal methods and systematically evaluated for their adsorption and separation performance toward C8 cyclohexane isomers through single-component and competitive batch adsorption experiments, dynamic breakthrough tests, and molecular simulations. Among the investigated materials, UiO-66-NO 2 demonstrated superior selectivity (α = 5.10) for cis-1,3-DMCH over ECH, with excellent regeneration stability over multiple cycles, significantly outperforming commercial activated carbons and zeolites. Mechanistic studies revealed that the enhanced selectivity arises from a dual mechanism combining geometric confinement effects and electronic recognition, where the oblate geometry and larger dipole moment of cis-1,3-DMCH enable preferential adsorption through strengthened C-H···O and C-H···NO 2 interactions, as confirmed by calculated binding energies (−37.15 kJ/mol for cis-1,3-DMCH vs. -22.13 kJ/mol for ECH) and diffusion coefficients. This work demonstrates rational MOF functionalization for efficient cycloalkane isomer separation, providing a promising strategy for coal-derived naphtha valorization.
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Fang Zheng,Lidong Guo,Rundao Chen,Feng Zhou,Zhiguo Zhang,Qiwei Yang,Yiwen Yang,Qilong Ren,Zongbi Bao
The separation of hexane isomer mixtures into their individual components is one of the most important while challenging industrial process to produce high-octane gasoline. Herein robust M(pz)[Ni(CN) 4 ], termed MpzNi (M = Co, Ni, pz = pyrazine) that can realize efficient separation of ternary mixtures into the pure, individual components. As optimal pore channels with double-accessible open metal sites providing the adsorbate-dependent affinity differences for molecular exclusion behavior via temperature programming, CopzNi reached optimum performance with not only exceptional selectivity of linear/monobranched alkanes and monobranched/dibranched alkanes, but also notably higher adsorption capacity than those of the previously reported adsorbents. Breakthrough experiments with equimolar ternary C6 alkane isomers and binary branched mixtures confirmed CopzNi can highly capture n -hexane and 2-methylpentane from their mixtures. The excellent separation efficiency, lower-energy regeneration, scalability, recyclability as well as high stability render the CopzNi a benchmark candidate for implementation in the current separation processes.
研究领域:
化学工程
·
材料科学
·
分离技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）