CHEMICAL ENGINEERING JOURNAL
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2023
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IF 15.1
Jian Guan,Xiangzeng Wang,Jingcheng Du,Quansheng Liang,Wen He,Ying Liu,Ji Ma,Chunwei Zhang,Jiangtao Liu
Polymers of intrinsic microporosity (PIMs) are promising candidates for carbon dioxide (CO 2 ) separation and capture from flue gas or natural gas. PIM-1, which has excellent gas permeation properties over the Robeson upper bound (1991), has been widely functionalized to further enhance the CO 2 permeability or selectivity. In this work, a simple and readily processive surface modification method has been proposed via hydrolysis of the PIM-1 membrane. The two hydrolysis processes by the acid method, amidation and carboxylation processes, have been conducted to functionalize the surface of PIM-1 membranes forming N A -PIM-1 and C A -PIM-1 membranes. The TGA, FT-IR spectra and NMR results verify that the composition and structure inside the PIM-1 membrane remain unchanged. XPS and NMR spectra demonstrate that the nitrile group at the surface was successfully functionalized with an amine group or carboxyl group. The CO 2 permeability and CO 2 /N 2 selectivity of the N A -PIM-1 membrane both increased to 4593.2 Barrer and 28.5, respectively. Another advantage of N A -PIM-1 membranes is the coordination site from introduced nitrogen atoms with zinc ions to form N A -PIM-1-Zn, which could further react with PEI to introduce amine-rich groups on the surface of the PIM-1 membrane. The CO 2 /N 2 selectivity of the N A -PIM-1-Zn-PEI membrane coated with PEI on the surface increases 45.4% compared to the unmodified PIM-1 membranes, with CO 2 permeability decreasing only 15.5% compared to the unmodified PIM-1 membrane. The N A -PIM-1 and N A -PIM-1-Zn-PEI membranes both surpass the Robeson upper bound (2008) even under mixed gas feeding, suggesting that surface modification of PIM-1 is a promising approach for CO 2 capture from natural gas and flue gas.
研究领域:
材料科学
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环境工程
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2023
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IF 9.5
Yonghong Wang,Kaixin Wang,Xinru Zhang,Jinping Li
Carbon molecular sieve (CMS) membranes are widely used for the separation of similar molecular kinetic diameter gas. However, their performance is limited by a large amount of discontinuous porous structures and a few adsorption affinity sites. Herein, we first prepared magnetic Co@NC@ZIF-8 nanoparticles , followed by introducing it into the polyimides matrix to design precursor membrane with vertical nanochain-like particle distribution by magnetic field induction. Afterwards, hybrid carbon molecular sieve (HCMS) membranes were prepared by pyrolyzing precursor with high-temperature under N 2 atmosphere, which had ordered microporous architecture and Co-N-C structure. Resultant HCMS membranes prepared by magnetic field induction had excellent gas separation performance, whose CO 2 , N 2 and CH 4 permeabilities were 27,050, 2614 and 622 Barrer, with CO 2 /N 2 , CO 2 /CH 4 and N 2 /CH 4 selectivities of 10.4, 43.5 and 4.2 respectively. These values far exceeded 2019 CO 2 /CH 4 and 2008 N 2 /CH 4 upper bounds as well as approached 2008 CO 2 /N 2 upper bound. The superior performance resulted from the vertically ordered nanochain-like channels for gas transport, which dramatically shortens the transport path of gas molecules to intensify shape sieving potential. Moreover, the Co-N-C structure on the wall of channels could facilitate CO 2 transport due to the π complexation. Additionally, a large quantity of nitrogen sites in the carbonized Co@NC@ZIF-8 enhance CO 2 adsorption selectivity owing to the acid-base interaction. More remarkably, after 30-day aging testing, it was found that HCMS membranes prepared by magnetic field induction had exceptional aging resistance compared to the pristine CMS membranes and one without magnetic field induction under the same aging environments.
研究领域:
材料科学
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化学工程
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膜技术
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气体分离
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2023
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IF 8.6
Xuebi Du,Shichao Feng,Jianquan Luo,Yongbing Zhuang,Weijie Song,Xuewei Li,Yinhua Wan
Amine-functionalized and metal doped metal–organic frameworks (MOFs) will enable further enhancement of CO 2 adsorption, which holds great promise in mixed matrix membranes (MMMs) for CO 2 /N 2 separation. Four kinds of UiO66 with different sizes have been successfully fabricated by introduction of Ce and/or amino groups in UiO66. The influence of Ce doping on the UiO66 is greatly related to the ligand. Compared with ZrUiO66, the CeZrUiO66 has bigger particle size, lower BET specific surface area and pore volume and a worse CO 2 adsorption capacity. Interestingly, the tendency of Ce-doped ZrUiO66-NH 2 is contrary to the aforementioned. In particular, bimetallic CeZrUiO66-NH 2 has an ultramicroporous structure, small particle size, rich crystal defect, superb CO 2 capture capacity and high CO 2 /N 2 adsorption selectivity, suggesting that the simultaneous introduction of Ce and amino groups is conducive to the enhancement of CO 2 separation. The intrinsic ultramicroporous structure of CeZrUiO66-NH 2 not only offers fast and low resistance transport channels for CO 2 , but also supplies more sites for CO 2 adsorption owning to the doping of Ce and the amino groups. As a result, Pebax/CeZrUiO66-NH 2 (3 wt%) MMMs show the CO 2 permeability of 100.7 Barrer and the CO 2 /N 2 ideal selectivity of 76.4, which is close to Robeson upper bound from 2008. Meanwhile, the Pebax/CeZrUiO66-NH 2 (3 wt%) MMMs present relatively good pressure resistance, which would be advantageous in terms of industrial application.
研究领域:
材料科学
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化学工程
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
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2018
·Vol. 6
·期 34
·16566-16573
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IF 9.931
Danke Chen,Wensen Wang,Wen Ying,Yi Guo,Donghui Meng,Youguo Yan,Rongxin Yan,Xinsheng Peng
The modern global climate change and global warming of Earth make it an urgent need to develop emerging CO2 capture and storage techniques. Herein, we first reported the use of WS2 nanosheets to construct laminated membranes for CO2 separation. However, the WS2 membrane showed poor CO2 separation performance with Knudsen selectivities for N2/CO2 (1.28), CH4/CO2 (1.72) and H2/CO2 (4.96). To improve the performance, an ionic liquid (IL) 1-butyl-3-methyl imidazolium tetrafluoroborate ([BMIM][BF4]) with high CO2 solubility and practically no vapour pressure was used for filling the nanochannels of the WS2 membrane. Compared to the bulk IL, the nanoconfined IL exhibits higher freezing temperature, shift of vibration bands and higher interaction energy between CO2 and ILs. Besides, the prepared WS2 laminated membrane with the nanoconfined ionic liquid shows excellent selectivities for CO2/N2 (153.21), CO2/CH4 (68.81) and CO2/H2 (13.56) in single gas measurements as well as good CO2 permeance due to the nanoconfinement of the IL. The simulation results further confirmed and explained the CO2 separation mechanism. It indicates that the nanoconfinement of ILs into the nanochannels of two-dimensional materials is a novel way to achieve CO2-philic membranes to efficiently separate CO2 from other light gases.
研究领域:
材料科学
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环境工程
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）