POLYMER
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2024
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IF 4.1
Zhe Cheng,Pei Wang,Yunlong Sun,Zhipeng Wang,Guangyuan Zhou
Gas separation membranes have a wide range of applications in industry, and there are two important factors in judging membrane standards permeability and selectivity. How to improve the selectivity of gas separation membranes while improving permeability is a challenge. In this study, poly (aryl ether sulfone) (PES) block copolymers were synthesized from fluorine-terminated polysulfone (PSF–F) and hydroxyl-terminated cardo PES containing phenyl substituted isoindolinone side group (PES-PPI-OH). Large side groups can enlarge the free volume and hinder chain movement to improve gas permeation behavior. Solvent-induced microphase separation of block copolymers by casting membranes with solvent benzyl alcohol (BA) can improve selectivity. The PSF- b -PES-PPI (10:10) BA membrane maintain good mechanical properties and tensile strength up to 93 MPa which compared to random polymer membrane rises to 14 MPa. Gas permeation at 23 °C showed that the O 2 /N 2 selectivity of PSF- b -PES-PPI (5:15)BA membrane was 10.6, which was the 2008 Robeson upper bound. Thus, poly (aryl ether sulfone) materials showed great potential application for O 2 /N 2 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
高影响因子
INORGANIC CHEMISTRY COMMUNICATIONS
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2025
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IF 5.4
Haodong Xie,Yuan Xue,Lei Zhang,Li Liu,Xiang Ni,Wenwen Song,Jingyun Qian,Lei Wang,Hongjun Zhu
The small pore aluminosilicate zeolites are always accompanied by the abundant framework aluminum content and the consequential extra-framework counterparts severely restrained its application in the gas separation process. In this work, the high-silica zeolite ERI (Si/Al = 7.3) was successfully fabricated using a OSDA in the potassium cation medium. It is found that the spatial distribution of aluminum sites in the ERI zeolite can be effectively tailored in the synthetic system with varying aluminum content. Furthermore, the ERI frameworks with spatially biased aluminum sites were also clarified. By combining multiple spectroscopy techniques and powder X-ray diffraction crystallography, the framework of aluminum sites related to host-guest interactions confined in high-silica ERI was clarified. In the gas separation of a binary mixture of O 2 /N 2 (21:79 v /v), the Sr 2+ cation-exchanged high-silica zeolite ERI exhibited efficient O 2 adsorption capacity: 0.74 mmol·g −1 and IAST selectivity: 2.89. These findings not only provide a structural foundation but also offer a model for the efficient separation of O 2 from multi-component gas mixtures.
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产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2020
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IF 3.573
Tong Zhang,Liming Deng,Pei Li
Previous studies demonstrate that decarboxylation cross-linking improves both the plasticization resistance and gas separation properties of a polymer precursor. However, when the decarboxylation reactions were carried out at low temperatures (350–400 °C), gas permeability was low because of the intrinsically low gas permeability of the polymer precursor. In this work, we synthesized a series of highly permeable polymer precursors having a triptycene-based Tröger’s base (TB) backbone structure and different amounts of carboxylic acid side groups. The TB polymer precursors were heated in a temperature range of 275–400 °C to induce cross-linking. After cross-linking, a more open polymer structure was obtained, resulting in an increase in the free volume fraction and gas permeability. The lowest cross-linking temperature was 350 °C and the separation performances of the cross-linked polymers surpassed the “2008 Robeson Upper Bound” for the CO2/CH4 and O2/N2 gas pairs. Moreover, the cross-linked polymers were not plasticized by CO2 at a pressure up to 30 bar.
研究领域:
材料科学
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聚合物化学
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气体分离
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产品关联
DOI
高影响因子
MACROMOLECULES
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2022
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IF 6.057
Wenwen Zhao,Wenqiang Ma,Shuangping Xu,Xintian Wang,Hongge Jia,Jingyu Xu,Mingyu Zhang,Yanqing Qu,Jiao Liu
Oxygen/nitrogen (O2/N2) permselective membranes are widely used in both industrial and medical applications. Polysiloxane is one of the most important membrane materials with high oxygen permeability, but its poor capacities for gas separation and membrane formation limit its practical use. In this study, a soluble imide-bridged polypentamethyltrisiloxane (IBPPMS) with a high molecular weight (Mn = 8.91 × 104) was designed and synthesized via a hydrosilylation reaction between polypentamethyltrisiloxane (PPMS) and N,N′-bis(3-allyl)pyromellitic diimide (DAI) in NMP under Karstedt’s catalysis. The ladder-like structure of sample was analyzed and determined through infrared spectroscopy (IR), nuclear magnetic resonance spectroscopy (1H NMR and 29Si NMR), and gel permeation chromatography (GPC). The IBPPMS membrane displays excellent thermal resistance. Furthermore, its O2 permeation performance achieves 47.1 barrer, and its separation factor reaches 7.11 with a feeding proportion of 50% each for O2/N2, exceeding the 2008 Roberson upper bound. Thus, it appears that membranes can achieve high selectivity and permeability as well as exhibit desirable thermal properties and sufficient stability when separating numerous industrial significant gas mixtures. The discovery of trapezoidal structural backbone of this polymer materials substantially affects their separation properties and sustained performances.
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
SEPARATION AND PURIFICATION TECHNOLOGY
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2020
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IF 5.774
Jiuli Han,Lu Bai,Shuangjiang Luo,Bingbing Yang,Yinge Bai,Shaojuan Zeng,Xiangping Zhang
Ionic liquids (ILs) are attractive and prospective materials used in membranes due to the nonvolatility, structure tunability, and the ability to tune the interface compatibility. The cobalt IL Bmim 2 Co(NCS) 4 possesses the porphyrin-like N4-coordinated cobalt center which could selectively and reversibly interact with O 2 . Herein the Bmim 2 Co(NCS) 4 as liquid-phase oxygen carrier was used to fabricate thin-film composite (TFC) membrane with the polymer of intrinsic microporosity (PIM-1). The microstructures, properties and gas separation performance of the membrane were compared with the TFC membrane which takes cobalt porphyrin (T(4-Cl)PPCo) as a carrier. We found that the addition of a small amount of T(4-Cl)PPCo can enlarge the d -spacing of packed chains of PIM-1 and significantly increase the fractional free volume (FFV) and the gas permeability of the membrane, but the selectivity is unsatisfactory. It is worth noting that adding Bmim 2 Co(NCS) 4 into the polymer can increase greatly the O 2 /N 2 selectivity which is higher than that of the membrane with T(4-Cl)PPCo. Although the addition of Bmim 2 Co(NCS) 4 decreases the d -spacing of packed chains of PIM-1, resulting in the slight decline of FFV and gas permeability of the membrane, the Bmim 2 Co(NCS) 4 /PIM-1 TFC membranes exhibit better O 2 /N 2 separation performance than the T(4-Cl)PPCo/PIM-1 TFC membranes in consideration of the Robeson upper bound.
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
CHEMICAL ENGINEERING JOURNAL
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2017
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IF 6.216
Ruxin Peng,Jihai Shao,Yuanlin Xie,Anwei Chen,Liang Peng,Qingru Zeng,Si Luo
Being that the influence of organic ligands on contaminant removal by nanoscale zero valent iron (nZVI) has been explored in quite a few studies, there is little information on reaction mechanisms of the ZVI-ligand system under different aeration conditions. The degradation of nitrobenzene (NB) by nZVI-oxalic acids (OA) was investigated under N 2 , O 2 and without aeration conditions. From the findings, it was evident that OA dramatically improved NB degradation by nZVI with all of the aeration conditions. Approximately 100% of NB was degraded by nZVI-OA+N 2 system after 60 min of reaction, followed in effectiveness by nZVI-OA+ without aeration (95%) as well as nZVI-OA+O 2 (85%). Operation parameters including OA concentration and pH had significant effect on the removal of NB in the nZVI-OA system. 3 mM OA concentration and pH 3.0 were found to be favourable. The Fe 2+ , total dissolved iron concentrations, pH and ORP values in the nZVI-OA systems had also been monitored. Intermediates and trapping experiments showed that reduction played a fundamental role in the NB degradation by nZVI-OA under N 2 or without aeration conditions. The formation of Fe(OA) 0 and Fe(OA) 2 2− complexes had lower standard ORP, which could improve the strength of reductant in the systems, and thus resulting in an increased degradation efficiency of NB by nZVI-OA+N 2 . Under O 2 aeration condition, the NB degradation process could be regarded as an oxidation . In the meantime, OA promoted the production of reactive oxidants species by speeding up the oxidation rates of Fe 2+ by O 2 and H 2 O 2 . Summarily, the improved reactivity of nZVI was largely as a result of the strong complexation ability of OA.
研究领域:
环境科学
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化学
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2017
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IF 3.359
Cheng Tan,Lei Li,Kongzhai Li,Dapeng Zhong
A novel method to separate As from high As-Sb dust using Fe 2 O 3 as a fixative under an O 2 -N 2 atmosphere is proposed. Here, Sb is oxidised and converted to Sb 2 O 4 and FeSbO 4 that remain in the roasted residue, and As is volatilized in the form of As 4 O 6 . The Sb 2 O 3 can be selectively oxidised from the dust by using 21 vol% O 2 , but the formation of amorphous substance (As-Sb-O) hinders the effective separation of As and Sb. Adding Fe 2 O 3 hinders the amorphous substance formation and destroys the structure of the solid solution ((Sb, As) 2 O 3 ) in the raw material by converting the Sb component in it to FeSbO 4 . Therefore, the volatilization rates of As and Sb can reach up to 90.53% and only 13.20%, respectively at a roasting temperature of 723 K, roasting time of 90 min, an Fe 2 O 3 dosage of 15 mass%, and O 2 content of 21 vol%.
研究领域:
冶金学
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环境科学
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产品关联
DOI
高影响因子
ACS Omega
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2021
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IF 3.512
Shuangping Xu,Wenqiang Ma,Hailiang Zhou,Yushu Zhang,Hongge Jia,Jingyu Xu,Pengfei Jiang,Xintian Wang,Wenwen Zhao
The synthesis of poly(methyhydrosiloxane) (PMHS) and N,N′-bis(3-allyl)pyromellitic diimide was optimized for O2/N2 separation. The membrane exhibits excellent mechanical and thermal properties and shows an O2/N2 selectivity of up to 4.44 with an O2 permeability of 31.0 Barrer; compared with polydimethylsiloxane (PDMS) and pure polyimide (PI) membranes, the separation selectivity shows a 107% increase for PDMS, and the permeation shows a 660% increase for pure PI. The obtained results were well above the ones reported on the literature for similar conditions opening the door for the preparation of a stable polysiloxane (PMHS-I) gas separation membrane with extraordinary O2/N2 separation performance.
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
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2023
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IF 9.5
Hongyong Zhao,Ting Song,Xiaoli Ding,Ruyi Cai,Xiaoyao Tan,Yuzhong Zhang
Membrane technology for O 2 /N 2 separation is a mature industrial unit. Membranes with excellent permeation-separation performance are still one of the critical requirements. The cobalt-based compounds have been well known for their good affinity for O 2 , which can facilitate O 2 transfer and improve the O 2 /N 2 selectivity in membranes. The cobalt-based compounds, moreover, have a magnetic responsive effect, which can lead to a further improvement in O 2 /N 2 separation under a magnetic field. A class of PIM-1 mixed matrix membranes (MMMs), containing cobalt-based ionic liquid (CILs)@polyarylate (aromatic polyester) (PAR) (core-shell) composite nanospheres (CILs@PAR (c-s) CNPs), were prepared. Chemical compositions of CILs@PAR (core-shell) CNPs were determined by Fourier transform infrared spectroscopy (FTIR). Morphologies and structures of CILs@PAR (core-shell) CNPs were observed by transmission electron microscopy (TEM). Gas adsorption properties of CILs@PAR (core-shell) CNPs were tested. Thermal properties of the (CILs@PAR (c-s) CNPs)/PIM MMMs were investigated by simultaneous thermal analysis (TGA-DSC). Gas permeation-separation performances of the (CILs@PAR (c-s) CNPs)/PIM MMMs were also reported. Compared with the original PIM-1 membrane, the (CILs@PAR (c-s) CNPs)/PIM MMMs display higher O 2 /N 2 selectivity because of cobalt-based ionic liquid as O 2 carrier, coupled with a reduction in O 2 permeability. With increasing the content of the CILs@PAR (c-s) CNPs, the O 2 /N 2 selectivity increases, and the O 2 permeability decreases. It is also found that, as a magnetic field on the MMMs, the O 2 /N 2 selectivity further increases; and it increases more, as a higher content of CILs@PAR (c-s) CNPs. Therefore, the (CILs@PAR (c-s) CNPs)/PIM MMMs exhibit excellent O 2 /N 2 selectivity of ∼5 coupled with good O 2 permeability of ∼140 Barrer under a 180 mT magnetic field and show great potential for air separation.
研究领域:
材料科学
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化学工程
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分离技术
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产品关联
DOI
高影响因子
HIGH PERFORMANCE POLYMERS
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2025
·
IF 1.6
Zhiqing Liang,Zhongying Liu,Xiuyuan Wei,Hui Wu,Chanjuan Liu,Xiaohua Huang
Bifunctionalized NH2-UiO-66-CF3 nanofillers were successfully prepared by grafting - CF3 on NH2-UiO-66 via aldehyde-amine condensation reaction and applied to the preparation of 6FDA-ODA/NH2-UiO-66-CF3 mixed matrix membranes (MMMs). The successful introduction of -NH2 and -CF3 groups was verified by FT-IR, XRD, and XPS characterization, and the integrity of the crystal structure was ensured. Due to the presence of hydrogen bonding, NH2-UiO-66-CF3 showed good interfacial compatibility with the polymer matrix. Due to the introduction of the - CF3 group, the MMMs exhibited excellent thermal stability (T10% > 500°C, Tg = 300°C–305°C), hydrophobicity (contact angle of 92.96–97.71), and mechanical properties (tensile strength of 74–85 MPa). The gas separation performance tests showed that the MMMs exhibited significantly improved gas permeability and selectivity compared to the pure 6FDA-ODA membranes, which was attributed to the fact that the -NH2 and -CF3 groups provided more adsorption sites for gases. In particular, the PI/NUF(10) MMMs showed the best performance, with permeabilities of 42.71, 9.22, and 92.79 Barrer for CO2, O2, and He, respectively, which were 248%, 213%, and 173% higher than those of the pure membranes. Meanwhile, the selectivities of CO2/N2, O2/N2 and He/N2 were improved by 37%, 24%, and 8%, respectively. Close to the Robeson upper limit, demonstrating excellent gas separation potential.
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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纳米技术
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Zixian Qin,Yuxiu Sun,Zhengqing Zhang,Chenxu Zhang,Chi Tang,Chenxu Geng,Zhihua Qiao
Oxygen/nitrogen (O 2 /N 2 ) separation is of great importance but faces huge challenges owing to their similar molecular size and close polarity. In this work, we construct a polymer of intrinsic microporosity (PIM-1) based mixed matrix membrane (MMM) for efficient O 2 /N 2 separation by using ZIF-8 as the sieving filler along with surface modification of o-carborane (o-CB) to strengthen selective N 2 adsorption fixation as well as polymer-filler interfaces. Markedly, the o-CB on the outer surface of ZIF-8 not only affords the requisite interfacial compatibility in molecular sieving MMMs, but also increases the diffusion difference between O 2 and N 2 by the preferential adsorption with N 2 molecules. This synergistic effect of molecular sieving and adsorption inhibition achieves efficient O 2 /N 2 diffusion differential separation. As expected, the optimal membrane with o-CB-ZIF-8 loading of 35 wt% exhibits an O 2 permeability of 796.5 Barrer and a mixed O 2 /N 2 selectivity of 8.9 with O 2 /N 2 (20:80, vol.) mixtures, exceeding the latest 2015 upper bound limits. Moreover, the according membrane module with o-CB-ZIF-8 loading of 20 wt% also displays moderate O 2 permeability of 391.7 Barrer and O 2 /N 2 selectivity of 5.5 under pressure of 1 bar. This work may provide a feasible platform for designing high-performance MOF-based membranes in air separations.
研究领域:
材料科学
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分离技术
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产品关联
DOI
高影响因子
PROCEEDINGS OF THE COMBUSTION INSTITUTE
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2024
·
IF 5.3
Nan Liu,Qi Chen,Xianwu Jiang,Jie Chen,Lidong Zhang,Jiaying Pan,Haiqiao Wei,Xingqian Mao
This work presents a three-stage hybrid nanosecond discharge (NSD) and direct current (DC) discharge assisted n -C 5 H 12 /O 2 /N 2 ignition with lower discharge energy and higher energy efficiency. The reaction rate coefficients between O 2 (a 1 Δ g ) and n -C 5 H 12 are updated by mass/Master equation simulation. The promotive ignition enhancement via reaction channel O 2 (a 1 Δ g ) + n -C 5 H 12 → C 5 H 10 + H 2 O 2 in the hybrid NSD/DC discharge is demonstrated. The results show that the ignition delay time of the three-stage hybrid plasma assisted ignition is 1–2 orders of magnitude shorter than that of the two-stage hybrid discharge when the reduced electric field strength in the DC discharge stage is over 10 Td. Meanwhile, the plasma-enhanced energy efficiency of three-stage hybrid discharge increases. This improved efficiency on ignition enhancement is due to the kinetic enhancement by the electronically excited species and radicals (O 2 (a 1 Δ g ), O( 1 D), N 2 (B) and O). The kinetic and thermal effects by plasma are effectively intergated to enhance ignition. However, more discharge energy deposited in the vibrationally excited states N 2 ( v ) in the two-stage hybrid discharge is less efficient on ignition enhancement due to the thermal contribution via vibrational-translational relaxation. In the aspect of NO x /N 2 O emissions, reduction efficiency of the three-stage hybrid discharge is two times higher than that of the two-stage hybrid discharge. By controlling the N/N( 2 D) production pathway e + N 2 → e + N + N( 2 D), the three-stage hybrid discharge reduces NO x and N 2 O production by 61.1 % and 90 %, respectively. The results show that the ignition delay time is non-monotonically dependent on the discharge pulse number. There exist optimal pulse number, reduced electric field and effective threshold power density of DC discharge to achieve maximum ignition enhancement and low NO x /N 2 O emissions. This study provides valuable insights into the use of NSD/DC hybrid discharge technology in advanced engines to achieve energy-efficient ignition enhancement and reduce NO x /N 2 O emissions.
研究领域:
能源科学
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环境科学
·
化学动力学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）