SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Zhenggang Wang,Jianwei Yuan,Renhao Li,Haipeng Zhu,Jingui Duan,Yanan Guo,Gongping Liu,Wanqin Jin
Compared with traditional separation methods, membrane-based technology shows advantages in energy efficiency for natural gas purification. To overcome the performance trade-off of conventional polymeric membranes, in this study, ZIF-301 MOF was employed as novel filler to fabricate 6FDA-DAM polyimide mixed-matrix membranes (MMMs) for CO 2 /CH 4 separation. A solvent exchange approach was proposed to remove the high-boiling-point solvent used for fabricating the MMMs. The microstructures and physico-chemical properties of the ZIF-301 fillers and ZIF-301/6FDA-DAM MMMs were characterized by SEM, EDX, XRD, IR, TGA, DSC and high-pressure sorption isotherms. The CO 2 /CH 4 transport properties through the MMMs were evaluated by permeation measurement at various feed pressures and analyzed by solution-diffusion model. The results showed that the incorporation of ZIF-301 into 6FDA-DAM enhanced both the CO 2 permeability and CO 2 /CH 4 selectivity, attributing to the preferential CO 2 sorption and aperture molecular sieving effect of the ZIF-301 filler. The MMM with optimal ZIF-301 loading of 20 wt% exhibited CO 2 permeability of 891 barrer and CO 2 /CH 4 of 29.3 that surpassed the 2008 Robeson upper-bound, suggesting that ZIF-301 based membrane could be a potential candidate for natural gas purification.
研究领域:
材料科学
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化学工程
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环境科学
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产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2025
·
IF 8.2
Yi Wang,Liang Li,Fangli Zhang,Huajiang Wang,Zhaoliang Cui,Zhaohui Wang,Xiaozu Wang
Mixed matrix membranes (MMMs) can significantly improve gas separation performance, but the type and state of the filler in the membrane matrix are key indicators for the development of MMMs. Therefore, in this work, 6FDA-DAM/ODA (1:1), metal–organic frameworks (MOFs) with different particle sizes (UiO-66 and UiO-66-NH2) were synthesized, and then MOFs were doped into 6FDA-DAM/ODA to prepare MMMs. The effects of the dopant materials and their particle sizes on the gas separation performance of the membranes were investigated by testing the permeability of the MMMs to H2, CO2, CH4, and N2. When the dopant material was UIO-66, the permeability and selectivity of MMMs for each gas were significantly improved compared with that of the original membrane; when the dopant material was 300 nm UIO-66-NH2 with a loading of 10 wt %, the permeability performance and the CO2/CH4 selectivity increased from 44.1 to 57.2 compared with that of the original membrane. The permeation performance for CO2, N2, and H2 and the selectivity for CO2/N2, H2/N2, and H2/CH4 were also significantly improved. In terms of comprehensive separation performance, doping 300 nm UiO-66-NH2 was better than doping 70 and 400 nm UiO-66-NH2 and also showed excellent performance in 50:50 (vol/vol) CO2/CH4 binary mixed gas separation. This work provides an idea for the fabrication of MMMs for high-performance gas separation.
研究领域:
材料科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Xue Yang,Yuxuan Wang,Jingxian Hua,Rujing Hou,Jinfeng Chen,Qihan Gong,Chongqing Wang,Yichang Pan
Plate-like or sheet-like porous materials with nanometer thickness have been considered as the preferred fillers to improve mixed-matrix membranes (mmms)-based separation. Herein, hexagonal Co-fa (HG-Co-fa) nanoplates were simply synthesized without the addition of any modifier and used as fillers to construct 6FDA-DAM-based MMMs for efficient CO 2 /CH 4 separation. HG-Co-fa nanoplates exhibit high dispersion and interface compatibility in 6FDA-DAM matrix. The results demonstrated that the CO 2 /CH 4 separation performance of 6FDA-DAM was obviously improved after the incorporation of HG-Co-fa nanoplates. The resultant MMMs with nanoplate loading of 10 wt% showed CO 2 /CH 4 selectivity of 27 and CO 2 permeability of 1419 Barrer at 25 ℃ and 0.2 MPa, surpassing 2008 Robeson upper bound. Meanwhile, the high lattice integrity and structural stability of HG-Co-fa nanoplates contribute to the excellent thermal and mechanical stability of MMMs, contributing to their anti-plasticization property up to 14 bar and long-term stability up to 240 h, indicating their potential for natural gas separation.
研究领域:
材料科学
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环境科学
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化学工程
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产品关联
DOI
高影响因子
MOLECULES
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2023
·Vol. 28
·期 5
·2028
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IF 4.6
Chaohua Song,Longfei Peng,Yinhui Li,Yawei Du,Zan Chen,Weixin Li,Cuijia Duan,Biao Yuan,Shuo Yan,Sibudjing Kawi
Novel polymers applied in economic membrane technologies are a perennial hot topic in the fields of natural gas purification and O2enrichment. Herein, novel hypercrosslinked polymers (HCPs) incorporating 6FDA-based polyimide (PI) MMMs were prepared via a casting method for enhancing transport of different gases (CO2, CH4, O2, and N2). Intact HCPs/PI MMMs could be obtained due to good compatibility between the HCPs and PI. Pure gas permeation experiments showed that compared with pure PI film, the addition of HCPs effectively promotes gas transport, increases gas permeability, and maintains ideal selectivity. The permeabilities of HCPs/PI MMMs toward CO2and O2were as high as 105.85 Barrer and 24.03 Barrer, respectively, and the ideal selectivities of CO2/CH4and O2/N2were 15.67 and 3.00, respectively. Molecular simulations further verified that adding HCPs was beneficial to gas transport. Thus, HCPs have potential utility in fabrication of MMMs for facilitating gas transport in the fields of natural gas purification and O2enrichment.Keywords:6FDA-based polyimide;hypercrosslinking polymers;gas transport;molecular simulations
研究领域:
材料科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
AICHE JOURNAL
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2022
·Vol. 68
·期 8
·e17688
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IF 4.167
Xi Chen,Guining Chen,Guozhen Liu,Gongping Liu,Wanqin Jin
Mixed-matrix membranes (MMMs), judiciously combining processability of polymer and remarkable separation performance of nanofillers, have been extensive pursuits for molecular separation process. Permeability matching between filler and polymer is one of the necessary requisites to desirable mixed-matrix effect. Considering the superior molecular sieving effect of UTSA-280 metal-organic frameworks on C 2 H 4 and C 2 H 6 , here, we report two types of UTSA-280/6FDA-polyimide MMMs toward C 2 H 4 /C 2 H 6 separation. The molecular sieving effect of UTSA-280 endowed 6FDA-DAM:DABA(3:2) membrane with simultaneous improvements in C 2 H 4 permeability and C 2 H 4 /C 2 H 6 selectivity. Optimally, when the filler reached 21.80 wt%, C 2 H 4 permeability and C 2 H 4 /C 2 H 6 selectivity was increased to 6.49 Barrer (by 15%) and 4.94 (by 32%), respectively. On the contrary, UTSA-280/6FDA-DAM MMMs showed undesirable mixed-matrix effect that C 2 H 4 permeability decreased meanwhile C 2 H 4 /C 2 H 6 selectivity nearly kept at polymeric pristine membrane level. It was found that permeability matching between two phases was responsible to these opposite mixed-matrix effects. More specifically, UTSA-280 had a relatively low gas permeability so that it required a less permeable polymeric matrix like 6FDA-DAM:DABA(3:2) to exert its molecular sieving effect. Furthermore, the optimal-matching 6FDA-matrix in permeability with UTSA-280 fillers was predicted by theoretical model. This work not only reports improving C 2 H 4 /C 2 H 6 separation performance via mixed-matrix formulation, but also emphasizes the importance of permeability matching between polymer and filler to realize the mixed-matrix effect.
研究领域:
材料科学
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化学工程
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膜技术
✓ 已验证
DOI
高影响因子
Membranes
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2023
·Vol. 13
·期 5
·461
·
IF 4.2
Yuxuan Zhao,Hongyan Wang,Xiangyun Liu,Xueping Zong,Jiangzhou Luo,Song Xue
The 6FDA-based network PI has attracted significant attention for gas separation. A facile strategy to tailor the micropore structure within the network PI membrane prepared by the in situ crosslinking method is extremely significant for achieving an advanced gas separation performance. In this work, the 4,4′-diamino-2,2′-biphenyldicarboxylic acid (DCB) or 3,5-diaminobenzoic acid (DABA) comonomer was incorporated into the 6FDA-TAPA network polyimide (PI) precursor via copolymerization. The molar content and the type of carboxylic-functionalized diamine were varied in order to easily tune the resulting network PI precursor structure. Then, these network PIs containing carboxyl groups underwent further decarboxylation crosslinking during the following heat treatment. Properties involving thermal stabilities, solubility,d-spacing, microporosity, and mechanical properties were investigated. Due to the decarboxylation crosslinking, thed-spacing and the BET surface areas of the thermally treated membranes were increased. Moreover, the content of DCB (or DABA) played a key role in determining the overall gas separation performance of the thermally treated membranes. For instance, after the heating treatment at 450 °C, 6FDA-DCB:TAPA (3:2) showed a large increment of about ~532% for CO2gas permeability (~266.6 Barrer) coupled with a decent CO2/N2selectivity~23.6. This study demonstrates that incorporating the carboxyl-containing functional unit into the PI backbone to induce decarboxylation offers a practical approach with which to tailor the micropore structure and corresponding gas transport properties of 6FDA-based network PIs prepared by the in situ crosslinking method.
研究领域:
材料科学
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化学工程
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DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2025
·
IF 9
Mengchen Wang,Jiayou Liao,Chengyun Gao,Jiwei Ma,Xianjie Meng,Yinghua Shen,Xu Wu,Yong Wang,Jinping Li
Hyperbranched polyimide (HBPI) membranes have emerged as promising materials for gas separation due to their loose interchain structure and large free volume. However, their widespread application is hindered by challenges such as complex synthesis procedures, high-cost monomers, and poor resistance to plasticization. In this study, a series of Trimesoylchloride (TMC)-branched 6FDA-based PI membranes were successfully synthesized using different contents of TMC as a branching agent to regulate the pore distribution. The molecular structure and degree of branching (DB) of HBPI were characterized using FTIR and 1 H NMR. The incorporation of TMC into the HBPI structure effectively enhanced the permeability and selectivity of the acyl chloride-branched PI membranes while improving thermal stability. The optimized membrane (A5-TMC content is 5%), exhibits the improving O 2 and CO 2 permeabilities of 176.52 and 930.94 Barrer combined with the O 2 /N 2 , CO 2 /N 2 and CO 2 /CH 4 selectivities of 4.68, 24.65 and 23.85, respectively. Particularly, the A5 HBPI membrane, with a DB value of 85.71%, demonstrated superior anti-aging properties compared to linear 6FDA-DAM membrane over 365 days. Most importantly, the 6FDA-DAM-TMC HBPI membranes significantly enhanced the resistance to plasticization at elevated CO 2 feed pressures, maintaining stability up to 300 psi and significantly outperforming the linear 6FDA-DAM membrane. This study provides an effective method for the fabrication of high-performance gas-separated polymer membranes with enhanced plasticization resistance and long-term durability for advanced gas separation applications.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2023
·
IF 9.5
Xiuling Chen,Lei Wu,Cong Xie,Shan Xu,Yanfang Fan,Nanwen Li
Carbon molecular sieve (CMS), as the gas separation membrane materials, still faces challenges for regulation pore diameter precisely. In this work, we propose to reconstruct the 6FDA-DAM-Br-85% polyimide CMS membranes by introducing 6,6'-(1,4-phenylenebis(((4-hydroxyphenyl)amino)methylene))bis(dibenzo[c,e][1,2] oxaphosphinine6-oxide) small molecule compound (DOPO- p -DP) as crosslinking agent to regulate the pore distribution. The crosslinked precursors were obtained via the reaction between C–Br bond in 6FDA-DAM-Br-85% polyimide and N–H bond in DOPO- p -DP compound, the precursors and CMS membranes (550 °C- 2 h) were characterized with ATR-TFIR, XRD and XPS. The pore size distribution of crosslinked CMS membranes was range in 4.5–8.0 Å from the N 2 adsorption data. The crosslinked CMS membranes exhibited excellent gas separation performance, which was strongly dependent on the mass fraction of DOPO- p -DP, an increasing mass fraction of DOPO- p -DP leaded to improve in gas selectivity, while reduced its permeability. The 6FDA-DAM-Br-85%/DOPO- p -DP-20% CMS membrane showed the impressive permeability and superior gas selectivity, the permeabilities of O 2 , CO 2 , and H 2 are 798, 3018, and 13560 Barrer combined with the O 2 /N 2 , CO 2 /CH 4 , and H 2 /CH 4 selectivities of 7.8, 65.6, and 294.8 respectively, the separation performances surpassed the latest trade-off relationship. In addition, the 20% of the DOPO- p -DP crosslinked CMS membrane revealed the superior aging behaviour than that of the 6FDA-DAM-Br-85% CMS membrane over 480 h aging under vacuum conditions.
研究领域:
材料科学
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化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2021
·
IF 8.742
Shan Xu,Xiaolong Ren,Ning Zhao,Lei Wu,Zhiguang Zhang,Yanfang Fan,Nanwen Li
The CO 2 -induced plasticization effects impose detrimental effects on polymeric membranes separation performance. To address this issue, a high-performance crosslinked brominated 6FDA-based polyimide (BMPI) is developed in this work, exhibiting highly suppressed plasticizing effects. The permeability and selectivity of polyimide precursor membranes are tuned by introducing bromine atoms into the polyimide structure, creating a best performing membrane with bromination degree of 60%. The membrane CO 2 permeability reaches 395 Barrer, and the selectivity of CO 2 /CH 4 increases from 22.0 for a non-brominated analogue to 26.0. The debromination induced crosslinked BMPI membranes are achieved upon thermal treatment within the temperature range of 150 °C–350 °C with varied crosslinking degree, resulting in large differences for the membrane separation performance. The completely crosslinked BMPI treated at 350 °C for 10 h demonstrates high CO 2 permeability of 483.6 Barrer and the CO 2 /CH 4 selectivity of 26.0. Most importantly, the crosslinking reaction greatly stabilizes the membrane performance against plasticization under high CO 2 feed pressure. Compared with the non-crosslinked membranes with a plasticizing pressure of 150 psia, the plasticization for the crosslinked membrane occurs at high CO 2 pressure of 600 psia. This study provides a facile approach for the preparation of high-performance gas separation polymeric membranes with enhanced plasticization resistance.
研究领域:
材料科学
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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
·
2020
·
IF 7.183
Guining Chen,Xi Chen,Yang Pan,Yufan Ji,Gongping Liu,Wanqin Jin
Mixed-matrix membranes (MMMs) based on metal-organic frameworks (MOFs) molecular sieves have been extensively studied in gas separation due to the high performance and good compatibility of MOF with polymers. In this work, 6FDA-based polyimides MMMs incorporating M-gallate (M = Ni, Co, Mg) MOF particles were fabricated for the first time and investigated for ethylene/ethane (C 2 H 4 /C 2 H 6 ) separation. By reducing synthesis temperature and introducing agitation, the Ni-gallate particles synthesized in flask (Ni-gallate(F)) with optimized conditions are smaller than Ni-gallate synthesized in autoclave (Ni-gallate(A)). The particle size was reduced from ~7 μm (Ni-gallate(A)) to ~0.8 μm (Ni-gallate(F)), which enables the formation of uniform MMMs. Because of the better compatibility with polyimide and higher adsorption performance of Ni-gallate than Mg-gallate and Co-gallate, the 6FDA-DAM MMM containing Ni-gallate(F) was capable of simultaneously improving C 2 H 4 /C 2 H 6 selectivity and C 2 H 4 permeability whereas the MMM with Mg-gallate(F) or Co-gallate(F) failed in performance enhancement. The 6FDA-DAM MMM with Ni-gallate(F) loading of 20% exhibited optimal C 2 H 4 /C 2 H 6 separation performance that surpassed the upper-bound of pure polymers. Detailed analysis of sorption and diffusion coefficients suggested that the enhanced transport properties in Ni-gallate(F) MMMs were attributed to the increase of sorption coefficient provided by the higher C 2 H 4 sorption capacity and selectivity, as well as the favorable gas diffusivity via moderately confined pores of the incorporated Ni-gallate(F) fillers.
研究领域:
材料科学
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化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2022
·
IF 10.53
Shan Xu,Ning Zhao,Lei Wu,Shuanyan Kang,Zhiguang Zhang,Guolong Huo,Zhongde Dai,Nanwen Li
Tuning the relationship between the microporous structure of carbon molecular sieve (CMS) membranes and the corresponding gas permeability performance enables optimization for gas separation applications. The pre-crosslinked structure of the precursor plays a key role in improving the performance of the CMS membrane. Herein, the thermally crosslinkable brominated 6FDA-based polyimide (BMPI) by debromination is prepared and selected as the precursor to fabricate high performance CMS gas separation membranes . By heat-treating the BMPI membrane at 350 °C for 10 h, the debromination-induced crosslinking exhibited higher permeability over the uncrosslinked precursors, as it forms a pre-crosslinked structure that is more stable at 550 °C. A representative BMPI-350/10h-550 °C CMS membranes pyrolyzed at 550 °C had CO 2 and O 2 permeabilities of 11169 and 2182 Barrer with a CO 2 /CH 4 and O 2 /N 2 ideal selectivity of 26.5 and 5.4. These values are much higher than that of the un-crosslinkable precursor (6FDA-DAM) derived CMS membrane (P CO2 = 3465, α CO2/CH4 = 21.1). Even at the high carbonization temperature of 800 °C, the as-obtained CMS membrane still show a promising CO 2 permeability of 1119 Barrer and a CO 2 /CH 4 ideal gas selectivity of 41.2. Importantly, the excellent gas separation performance of CMS membranes obtained in this work exceeds the Robeson's upper-bound. This work outlines a new protocol to tailor CMS membrane microstructures to meet high permeability performance needs. These CMS membrane materials hold great potential in corrosive natural gas purification applications.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2023
·
IF 4.2
Xiaobing Wang,Qi Ding,Rimin You,Cong Yu,Yujia Li,Junjie Zhao,Xili Cui,Huabin Xing
The development of efficient membranes for ethylene/ethane (C2H4/C2H6) separation is highly important. Here, we report the development of a series of new mixed matrix membranes (ZnAtzPO4/6FDA-DAM MMMs) based on a microporous material with phosphate anion pillar ZnAtzPO4 (Atz = 3-amino-1, 2, 4-triazole) and 6FDA-DAM polymer matrix. Compared with the pure 6FDA-DAM membranes, the C2H4 permeability and the C2H4/C2H6 selectivity of 10 wt % ZnAtzPO4/6FDA-DAM MMMs were simultaneously increased by 46 and 6%, breaking the trade-off between permeability and selectivity. Interestingly, the separation performance of ZnAtzPO4/6FDA-DAM MMMs at 10 wt % for the equimolar C2H4/C2H6 gas mixture was 105.0 Barrer and 3.90, which surpassed the 2013 upper bound of C2H4/C2H6. For ZnAtzPO4/6FDA-DAM MMMs with 10 wt % filler loading, both the solubility selectivity and the diffusion selectivity continued to rise concurrently, enhancing the C2H4/C2H6 separation performance of ZnAtzPO4/6FDA-DAM MMMs. This work generates a useful concept for the design and fabrication of high-performance MMMs.
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