Journal of Environmental Chemical Engineering
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2023
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IF 7.7
Na Yang,Hao Jiang,Longfei Zhang,Xiang Wang,Luhong Zhang,Yongli Sun,Bin Jiang
Spinel oxides can be considered effective heterogeneous catalysts in activating peroxymonosulfate (PMS) for wastewater decontamination . However, the intrinsic characteristics of agglomeration and metal ion leaching impede its further application. In this work, to further improve the catalytic efficiency and stability of the catalyst, ZIF-8 was employed as the candidate and further etched by tannic acid (TA) to obtain a core-shell structure with less mass transfer resistance. Following this, CoFe 2 O 4 was anchored on TA-ZIF-8 matrix via a hydrothermal method. Benefiting from the tailored core-shell structure and high activity of CoFe 2 O 4 , the as-prepared CoFe 2 O 4 @TA-ZIF-8 catalyst shortened the mass transfer distance of radical to target pollutant, thus realizing high radical utilization efficiency. Accordingly, 98.1% of tetracycline (TC) can be eliminated in 30 min with kinetic constants 3.15 times higher than pristine CoFe 2 O 4 . Besides, the TC degradation efficiency can still maintain 84.1% after five consecutive cycles with cobalt leaching lower than 0.306 mg/L, showing favorable stability compared with pristine CoFe 2 O 4 . Furthermore, electron paramagnetic resonance (EPR) and quenching experiments exhibited that singlet oxygen and sulfate radicals play dominant roles in TC degradation processes. This work fabricates an efficient CoFe 2 O 4 @TA-ZIF-8 heterogeneous catalyst for degrading refractory TC, which may possess potential applications in wastewater treatment .
研究领域:
环境科学
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催化材料
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产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2024
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IF 8.4
Yuanyuan Wang,Suyue Zhong,Shumin Li,Yangyang Dai,Wenjun Su,Jian Li
Rapid industrialization poses a serious threat to the balance of ecosystems and environmental sustainability, and the application of membrane technology is an effective way to alleviate this situation. Two-dimensional (2D) MXene nanosheets are superior materials for constructing high-performance separation membranes, but their biggest drawback is that they are prone to agglomeration. After alkalizing them, the obtained alkaline MXene (TCOH) nanosheets have hydroxyl-rich surfaces, stabilized structure and great affinity for CO 2 . Based on this, a self-supported TA-ZIF-8/TCOH@Pebax mixed matrix membranes (MMMs) with block polymer Pebax-1657 as matrix and TA-ZIF-8/TCOH as composite filler were prepared in this work. ZIF-8 was modified with tannic acid (TA) to enrich the surface with hydroxyl groups, yielding TA-ZIF-8 that is both pro-CO 2 and well interfacially compatible. The using of TA-ZIF-8 not only improves the selectivity of the separation membrane, but also its mutually repulsive electrostatic force with TCOH can expand the layer spacing of TCOH nanosheets as much as possible, which leads to a rich gas transportation channel of the membrane. Experiments have shown that the prepared TA-ZIF-8/TCOH@Pebax MMM had outstanding separation performance beyond the 2019 Robinson upper bound when the content of TA-ZIF-8 was appropriate. Also, the TA-ZIF-8/TCOH@Pebax MMM showed superior thermal stability, durability and mechanical properties. In summary, the strategy of combining nanoparticles and nanosheets as composite fillers in this study provides an effective way to regulate the low permeance of MMMs. In the meantime, the application of TCOH provides a novel idea for further research on gas separation membranes.
研究领域:
材料科学
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环境工程
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产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
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2023
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IF 7.7
Chunmei Gao,Peng Zou,Shifeng Ji,Yunqing Xing,Jiaonan Cai,Jinjian Wu,Tianyang Wu
Herein, we report a preparation method based on a modified zeolite imidazolate skeleton loose nanofiltration membrane used to achieve the efficient separation of salt and dye from dye wastewater. In this study, negatively charged hydrophilic TA@ZIF-8 was synthesized using a tannin surface-functionalization-assisted etching process by tannic acid (TA). A novel, highly negatively charged, and loose nanofiltration membrane was then prepared by adding TA@ZIF-8 to a polyethyleneimine (PEI) and tricarboxylic acid (TMA) crosslinking system. The addition of TA@ZIF-8 nanoparticles not only changed the degree of crosslinking of PEI/TMA but also provided a preferential channel for water molecules, thereby improving the flux of the membrane. Then, the success of TA@ZIF-8 NPs and membranes preparation were verified by SEM, XRD, FT-IR, TGA , BET, XPS and other methods. The results showed that the optimal preparation conditions were 0.020 wt% TA@ZIF-8 loading, and the contact angle of the membranes decreased from 79.8° to 53.7°. The water flux of the membrane is 81 L·m −2 ·h −1 ·bar −1 , which is 1.5 times that of PEI/TMA membrane. In addition, TA@ZIF-8–2 membrane not only has high rejection rate for Methyl blue (98.7 %), Toluidine blue (89.6 %), Cr 6+ (91.2 %), but also maintains high transmittance for NaCl and Na 2 SO 4 . Besides, the separation performance of the membrane was stable for a long time in a mixed solution of dye and salt and excellent antifouling performance. Therefore, the loose TA@ZIF-8/PEI/TMA nanofiltration membrane has broad application prospects in printing and dyeing wastewater treatments .
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2022
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IF 9.136
Guangyong Zeng,Yongcong Liu,Qingquan Lin,Shengyan Pu,Size Zheng,Micah Belle Marie Yap Ang,Yu-Hsuan Chiao
Industrial development resulted to an increase in discharge of hazardous oily wastewater with multi-component, which gravely threatens human health and the ecosystem. This is a huge challenge ushered in membrane technology. Recently, two-dimensional material, MXene has been demonstrated as a potential candidate for the construction of functional membranes. A novel TA-ZIF-8@MXene metal–organic framework (MOF) composite membrane has been fabricated and exploited for oily wastewater treatment. The composite membrane (T-M4) exhibited an excellent water flux (5347.36 L·m −2 ·h −1 ) after the incorporation of ZIF-8 modified by tannic acid (TA) nanoparticles. Moreover, the MOF-MXene composite membrane possessed an excellent chemical stability and high oil/water emulsion separation performance. The experimental results showed that the rejection ratios of T-M4 composite membrane for three different oil/water emulsions reached more than 98%. Furthermore, the chemically stable TA-ZIF-8@MXene/CA composite membrane showed an excellent performance having more than 84% flux recovery ratio (FRR) during multi-cycle oil/water emulsion filtration with neutral, acidic, alkaline, and salty media. In addition, molecular dynamics simulations were used to reveal the separation mechanism of the composite membrane. The investigation successfully applied MXene membrane materials to micron-level separation, which provided the reference for the application of MXene in O/W 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
危险品化学品经营许可证（带存储）