SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Guangcan Huang,Tongxin Liu,Haoxin Peng,Yabo Xie,Qiang Chen,Jian-Rong Li
Mixed-matrix membranes (MMMs) incorporating Metal-Organic Frameworks (MOFs) represent a promising approach for gas separation, which can combine the advantages of selective adsorbents and processable polymers, and display great potential in the gas separation process. However, the further application of MMMs is severely impeded owing to the non-ideal interface between fillers and polymer matrix . In this work, a series of MIL-101(Cr) nanofillers, equipped with different kinds of counter anions were introduced to regulate the chemical microenvironment of the MMMs and improve the interfacial relationship between inorganic filler and polymer. The filler of MIL-101-HNO 3 exhibits improved dispersibility in solvents and heightened interface relationship with the polymer matrix (PIM-1) due to its optimal particle size and distinctive exposure of crystallographic planes. Moreover, gas sorption isotherms reveal that the MIL-101-HNO 3 MOF show reduced N 2 adsorption capacity. Therefore, the MOF filler of MMMs were optimized rationally by microenvironment regulate strategy, leading to the MIL-101-HNO 3 /PIM-1 MMMs achieve high CO 2 permeability and exceptional CO 2 /N 2 ideal selectivity (CO 2 = 14879 barrer, CO 2 /N 2 = 24.3), surpassing the latest 2019 upper bound. That makes MIL-101-HNO 3 /PIM-1 a potential candidate for the selective removal of CO 2 from stack gas and provides new insights into the regulation of the MMMs nanofiller microenvironment.
研究领域:
材料科学
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化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Lingjia Ma,Jiongliang Yuan,Zhaotao Liu,Yiqing Luo,Yuning Su,Kunye Zhu,Zefeng Feng,Huihua Niu,Shuaishuai Xiao,Jianjun Wei,Xu Xiang
The electrocatalytic synthesis of high-value-added urea by activating N2 and CO2 is a green synthesis technology that has achieved carbon neutrality. However, the chemical adsorption and C–N coupling ability of N2 and CO2 on the surface of the catalyst are generally poor, greatly limiting the improvement of electrocatalytic activity and selectivity in electrocatalytic urea synthesis. Herein, novel hierarchical mesoporous CeO2/Co3O4 heterostructures are fabricated, and at an ultralow applied voltage of −0.2 V, the urea yield rate reaches 5.81 mmol g–1 h–1, with a corresponding Faraday efficiency of 30.05%. The hierarchical mesoporous material effectively reduces the mass transfer resistance of reactants and intermediates, making it easier for them to access active centers. The emerging space-charge regions at the heterointerface generate local electrophilic and nucleophilic regions, facilitating CO2 targeted adsorption in the electrophilic region and activation to produce *CO intermediates and N2 targeted adsorption in the nucleophilic region and activation to generate *N ═ N* intermediates. Then, the electrons in the σ orbitals of *N ═ N* intermediates can be easily accepted by the empty eg orbitals of Co3+ in CeO2/Co3O4, which presents a low-spin state (LS: t2g6eg0). Subsequently, *CO couples with *N ═ N* to produce the key intermediate *NCON*. Interestingly, it was discovered through in situ Raman spectroscopy that the CeO2/Co3O4 catalyst has a reversible spinel structure before and after the electrocatalytic reaction, which is due to the surface reconstruction of the catalyst during the electrocatalytic reaction process, producing amorphous active cobalt oxides, which is beneficial for improving electrocatalytic activity.
研究领域:
材料科学
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电化学
·
催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
·
2021
·
IF 3.975
Hui Wang,Yunxia Ni,Zhiyue Dong,Qiang Zhao
Interface compatibility is crucial to performance and robustness of nanocomposite membranes for molecular separation. In this work, a covalent crosslinking method was exploited to fabricate polydimethylsiloxane/metal-organic-frameworks (PDMS/MOFs) mixed matrix membranes with improved interfacial compatibility. Zirconium MOF particles (UiO-66-NH 2 ) were grafted with methoxysilane groups, which further formed covalent crosslinks with silanol terminated PDMS matrix. The strengthened interfacial compatibility prevented sedimentation and aggregation of MOF particles in PDMS precursor solution during the solvent evaporation process, thus the composites showed good membrane formation ability at high MOFs loading (60 wt%). Tensile strength of the hybrid membrane is 2.8 times improved while retaining good flexibility. Moreover, the CO 2 /N 2 selectivity and CO 2 permeability of the PDMS composite membrane incorporated with 40 wt% UiO-66-MS particles are improved by 1.3 times and 0.7 times, respectively.
研究领域:
材料科学
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环境工程
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2015
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IF 2.587
Song Zhao,Xiaochang Cao,Zijian Ma,Zhi Wang,Zhihua Qiao,Jixiao Wang,Shichang Wang
In this work, imidazolate framework ZIF-8 nanoparticles were synthesized and incorporated into a poly(vinylamine) (PVAm) coating solution. The chemical structure of a PVAm/ZIF-8 film was characterized by X-ray diffraction and attenuated total reflectance Fourier transform infrared spectroscopy techniques. Mixed-matrix membranes (MMMs) were developed by coating the PVAm/ZIF-8 mixed dispersion on a polysulfone (PSf) support membrane. Surface and cross-sectional scanning electron microscopy images of the MMMs were employed to observe the dispersion of nanoparticles in the polymer matrix. The CO2 permeance and CO2/N2 selectivity of the MMMs were evaluated by using a CO2/N2 mixture gas. Optimal preparation parameters for the MMMs were achieved by varying the incorporated ZIF-8 contents in the coating solution and the wet coating thickness. The effect of incorporated ZIF-8 on improving the gas permselectivity was revealed, and the mechanism of CO2-facilitated transport in the PVAm/ZIF-8/PSf membrane was analyzed. The CO2/N2 separation performance of PVAm/ZIF-8/PSf membranes with different wet coating thicknesses was also evaluated at 22–60 °C to analyze the changes of the gas permselectivity with increasing temperature.
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
Chemistry-An Asian Journal
·
2021
·Vol. 16
·期 20
·3141-3150
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IF 4.568
Haoyu Wang,Jing Zheng,Jing Zhao,Wanqin Jin
Graphical Metal ions are successfully incorporated into GO channels , which contribute to facilitating CO 2 transport, decreasing N 2 solubility, hindering N 2 diffusion, and form multiple interactions with GO nanosheets, thus achieving the remarkably improved CO 2 /N 2 separation performance (with separation factor increasing 12.2 times) and excellent long-term stability. Graphene oxide (GO) membranes holds great potential for high-performance CO 2 capture. Aiming at enhancing the CO 2 separation performance and structural stability of GO membranes, functionalizing GO channels with metal ions confers a promising strategy. In this study, we reported the fabrication of metal ion-incorporated GO membranes with remarkably improved CO 2 /N 2 separation performance. The metal ions within GO channels contribute to facilitating CO 2 transport, decreasing N 2 solubility, hindering N 2 diffusion, and form multiple interactions with GO nanosheets. After introducing Mg 2+ ions, the CO 2 /N 2 separation factor of GO membrane is remarkably increased from 4 to 48.8 with the CO 2 permeance increases 1.5 times. Moreover, the separation performance of the GO-Mg 2+ membranes shows an excellent long-term stability owing to the structural robustness. This study could provide insights into the regulation of the microstructure of metal ion-functionalized GO membranes for highly selective transport of specific molecules.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2024
·
IF 4.8
Kunpeng Liu,Yixuan Yu,Qi Wang,Lingtong Kong,Tianjun Sun
A comprehensive investigation was conducted to explore the adsorption behaviors of CH 4 over N 2 on ultra-microporous Al/Zr-FDCA frameworks, which were synthesized specifically using the eco-friendly and bio-sourced 2,5-furandicarboxylic acid (FDCA). Characterization results revealed that both Al-FDCA and Zr-FDCA exhibited similar specific surface area and surface groups, leading to comparable methane uptake per-unit mass at atmospheric pressure. However, the presence of Zr nodes generated ultra-micropores around 0.43 nm in size, leading to a pronounced affinity for CH 4 . Zr-FDCA demonstrated a higher CH 4 /N 2 selectivity (8.90) calculated from the isotherms compared to Al-FDCA (3.86). Furthermore, breakthrough experiments indicated that under the same dynamic conditions, Zr-FDCA exhibited 1.5 times higher CH 4 uptake per unit volume and 2.5 times higher CH 4 /N 2 selectivity when compared to Al-FDCA. Initially, a four-step VPSA process was simulated to investigate the separation of CH 4 /N 2 mixture, in which the effects of feed-gas flow rate, adsorption time, adsorption pressure, and desorption pressure in VPSA cycle were extensively evaluated to enhance the purity and recovery of methane. Subsequently, a six-step process was employed for further optimization, achieving a purity of 95.9 % and a recovery of 99.1 %. The obtained results demonstrated the reliability of the established model and highlighted the significant potential of Zr-FDCA for CH 4 /N 2 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
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2023
·
IF 7.4
Hongxia Fang,Chuncai Zhou,Shihai Xu,Jiaqian Shi,Yunhu Hu,Guijian Liu,Lei Wu
Metal-organic frameworks (MOFs) are considered one of the promising adsorbents for CH 4 /N 2 separation. However, MOFs commercialization is a big challenge since their synthetic materials are expensive and not environmentally friendly. Herein, the dealumination solution obtained from coal fly ash (CFA) using sulfuric acid as an extracting agent through direct leaching and roasting technologies was applied as metal feedstock to prepare CFAx-FumMOF-y and compared to aluminum fumarate MOF (Al-FumMOF) in morphology, surface area, micropore volume, and CH 4 /N 2 selective separation. The results indicated that CFAx-FumMOF-y exhibited closely similar surface area (1164.94–1073.08 m 2 /g) and micropore volume (0.40–0.36 cm 3 /g) to Al-FumMOF (1287.55 m 2 /g, 0.42 cm 3 /g), even there were no detectable differences in CH 4 uptakes (CFAx-FumMOF-y, 21.93–20.69 cm 3 /g; Al-FumMOF, 22.13 cm 3 /g) at 298 K and 1.0 bar, suggesting that the impurity metal species in dealumination solution hardly affect textural properties and gas uptakes. Moreover, the isosteric heat of adsorption (Q st ) and IAST CH 4 /N 2 selectivity of CFAs-FumMOF-1 (19.25–17.84 kJ/mol) and CFAb-FumMOF-1 (18.83–18.64 kJ/mol) were slightly superior to Al-FumMOF (17.83.64–16.86 kJ/mol, 4.87), suggesting that CFAx-FumMOF-1 played an identical role as Al-FumMOF in gases separation. The cyclic regeneration experiments and binary breakthrough tests further confirmed that CFAx-FumMOF-y was feasible for practical application. This study provides a new perspective for reducing the production cost of MOFs as well as realizing high-value utilization of CFA.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2022
·
IF 10.53
Li Yin,Dongfeng Li,Hongxia Guo,Shuai Wang,Tiexin Zhang,Yunling Liu,Fangyuan Gai,Xiaogang Zhao
Incorporating functional materials into polymer precursors is an effective way to prepare carbon molecular sieve (CMS) membranes for solving the trade-off problem between permeability and selectivity of gas separation. In this work, we induced ZIF-8 nanoparticles (from 5 to 20 wt%) as a doping agent to construct a series of phenolphthalein-based cardo poly (arylene ether ketone) (PEK-C) -based hybrid carbon molecular sieve (ZCMS) membranes for CO 2 /N 2 separation via an oxidation and a carbonization process with pyrolysis temperature in the range of 500–700 °C. The carbonized ligand and metal centre of ZIF-8 offered additional pores of carbon matrix, which tailored the ultramicropores of ZCMS membranes for both excellent CO 2 permeability and selectivity. By treating with the temperature of 600 °C, ZCMS-600-15 (ZCMS membrane based on 15 wt% of ZIF-8-doped PEK-C) exhibited the highest CO 2 permeability of 8902 Barrer, which was 1.8 times higher than that of CMS-600 (CMS membrane based on naked PEK-C). ZCMS-600-15 showed an ideal CO 2 /N 2 selectivity value of 42.2, which is also higher than that of other samples, indicating that the appropriate doping amount of ZIF-8 is 15 wt% and the proper carbonization temperature is 600 °C. Moreover, among all the samples, ZCMS-600-15 also showed a superior CO 2 permeability of 8285 Barrer and the highest CO 2 /N 2 selectivity of 24.08 for an equimolar mixture of CO 2 and N 2 , far exceeding the 2008 Robeson upper bound. Therefore, our results suggest that incorporating MOFs into polymer precursors to prepare hybrid carbon molecular sieve membranes by carbonization process could solving the trade-off problem between permeability and selectivity, introducing new possibilities for industrial application.
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 Environmental Chemical Engineering
·
2023
·
IF 7.7
Xingqian Wang,Yifei Wang,Yongjiang Shan,Xuerong Wang,Yingdong Yang,Fei Zhang,Xiangshu Chen
In recent years, membrane separation technology has received extensive attention in CO 2 /N 2 separation. Carbon nanotubes (CNTs) were regarded as ideal fillers for constructing high permeability mixed matrix membranes (MMMs) due to their special tubular structure. However, the interfacial compatibility between CNTs and organic polymer phases is a large challenge, seriously hindering the development of carbon-based mixed matrix membranes. In this work, we proposed a novel polyethyleneimine (PEI) surface functionalization strategy to effectively improve the compatibility between multi-walled carbon nanotubes (MWCNTs) and Pebax-1657. The as-prepared PEI@MWCNTs/Pebax-1657 MMMs were analyzed by XRD, EDS, FTIR, TG, etc. The PEI can improve the compatibility of MWCNTs with the polymer matrix. In addition, the abundant amino groups in the PEI structure can provide ample active sites for CO 2 , which can improve CO 2 permeability and CO 2 /N 2 selectivity simultaneously. Combining the low resistance of MWCNTs to gas transport, the membrane showed 178.08% enhancement in selectivity (82.06) of CO 2 /N 2 compared to the pristine membrane with 152.49% increment in the permeability (150.51 Barrer) of CO 2 . This work provides a novel strategy for preparing carbon-based mixed matrix membranes with high gas separation performance.
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
MICROPOROUS AND MESOPOROUS MATERIALS
·
2022
·
IF 5.876
Xiaoli Ding,Yongfu Tang,Hongyong Zhao,Qingping Xin,Yuzhong Zhang
Hollow SAPO-34 with an average particle size of ca .370 nm was synthesized by selective etching its precursor under the controlled alkaline condition. Subsequently, freestanding mixed matrix membranes were synthesized by UV-induced in-situ polymerization of the mixture of hollow SAPO-34, the fluorinated monomer , and the trifunctional cross-linker. The structure and the physical characteristic of hollow SAPO-34 and membranes were characterized by scan electron microscope, wide-angle X-ray diffraction, etc. The effect of the hollow SAPO-34 loading amount on the gas permeation-separation performance of mixed matrix membranes was investigated. The results showed that hollowing out SAPO-34 improved the N 2 /CH 4 sorption selectivity and converted the crystals from preferential adsorption of N 2 to preferential adsorption of CH 4 , the incorporation of hollow SAPO-34 into membranes increased the N 2 /CH 4 solubility selectivity and the permeability. The optimal membrane exhibited a 39-fold increase in N 2 permeability from 6.9 × 10 −13 to 2.7 × 10 −11 cm 3 (STP)cm·cm −2 ·s −1 ·Pa −1 at 0.2 MPa and 35 °C without the loss of N 2 /CH 4 permselectivity, which exceeded the 2008 Robeson upper bound.
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
Membranes
·
2022
·Vol. 12
·期 8
·786
·
IF 4.562
Xingqian Wang,Yuping Zhang,Xinwei Chen,Yifei Wang,Mingliang He,Yongjiang Shan,Yuqin Li,Fei Zhang,Xiangshu Chen,Hidetoshi Kita
Fillers play a critical role in the performance of mixed matrix membranes (MMMs). Microporous metal azolate frameworks (MAFs) are a subclass material of metal–organic frameworks (MOFs). Due to the uncoordinated nitrogen of the organic ligands, MAF-7 (SOD-[Zn(mtz)2], Hmtz = 3-methyl-1,2,4-triazole, window: d = 0.34 nm) shows excellent CO2adsorption performance. In this work, Pebax 1657/MAF-7 MMMs were prepared by a sample solution casting method with MAF-7 particles as fillers for the first time. By means of X-ray diffraction (XRD), scanning electron microscope (SEM), infrared radiation (IR), and thermogravimetry (TG), the compositional and structural properties of the mixed matrix membrane with different filler content were analyzed. The results show that the compatibility of MAF-7 and Pebax is good with a filler content of 5 wt.%. The pure gas testing showed that mixed matrix membrane has a high ideal CO2/N2selectivity of 124.84 together with a better CO2permeability of 76.15 Barrer with the optimized filler content of 5 wt.%. The obtained membrane showed 323.04% enhancement in selectivity of CO2/N2and 27.74% increase in the permeability of CO2compared to the pristine membrane at 25 °C and 3 bar. The excellent separation performance may be due to the ligands that can afford a Lewis base active site for CO2binding with the uniform dispersion of MAF-7 particles in Pebax and the favorable interface compatibility. The obtained membrane overcomes the Robeson’s upper bound in 2008 for CO2/N2separation. This work provides a new strategy by utilizing MAFs as fillers with triazole ligand to enhance the gas separation performance of mixed matrix membranes.
研究领域:
材料科学
·
气体分离
·
膜技术
✓ 已验证
DOI
高影响因子
Inorganic Chemistry Frontiers
·
2023
·Vol. 10
·期 19
·5700-5709
·
IF 7
Yixian Liu,Ruqiang Wu,Yunliang Liu,Peiji Deng,Yaxi Li,Yuanyuan Cheng,Yongchao Du,Zenan Li,Xiong Yan,Naiyun Liu,Zhenhui Kang,Haitao Li
As an environmentally friendly and sustainable method for ammonia synthesis, nitrogen reduction reaction (NRR) by electrocatalysis possesses several advantages, including viability under mild conditions, abundant reaction raw materials and low energy consumption, and thus it is supposed to be a promising alternative to the traditional Haber–Bosch process. However, the stable NN bonds in the nitrogen (N2) and the competing hydrogen evolution reaction (HER) put harsh requirements on catalysts. In this study, the CoS/MoS2 heterojunction catalyst where CoS nanoparticles are anchored on the MoS2 nanosheets is reported as a high-efficiency NRR catalyst. The catalysts have high NH3 yield (23.23 μg h−1 mgcat.−1), reasonable faradaic efficiency (FE, 12.63%) and long-term electrochemical stability under −0.45 V vs. RHE in 0.1 M Na2SO4 solution, whose performance is better than MoS2 and CoS. The TPV results show rapid interfacial electron transfer and good conductivity of the material, and the DFT calculation reveals that the CoS attached to the (100) plane effectively enhances N2 adsorption and catalysis performance.
研究领域:
材料科学
·
电化学
·
催化
·
可持续化学
✓ 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）