Journal of Energy Chemistry
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2020
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IF 7.216
Huimin Liu,Yidan Zhang,Jingshan Luo
Ammonia synthesis by electrocatalytic nitrogen reduction reaction (NRR) is considered as a promising alternative to the Haber−Bosch process. However, due to the extremely low ammonia yield and easily accessible extraneous contamination in the laboratory, NRR study always suffers from fluctuation and variability. Finding and eliminating all kinds of possible extraneous contamination is crucial to evaluate the performance of electrocatalytic ammonia synthesis accurately. In this work, we systematically explored two factors that affect NRR results but are easy to be ignored: the selection of membrane for NRR and the unconscious N-source in NRR catalysts. After series of experiments, we proposed a low-cost and almost pollution-free Celgard 3501 membrane as the separator for NRR to avoid the adsorption and release of ammonia by the membrane. In addition, we proposed a pre-reduction strategy to remove residual or adsorbed NO x contaminants in catalysts. These two solutions will help the community to evaluate the NRR activity more accurately.
研究领域:
化学工程
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材料科学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
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2025
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IF 4.3
Zhijian Jiang,Fang Wang,Bingyao Sun,Ying Wang,Zushun Xu,Quanyuan Zhang
Electrodialysis provides a sustainable strategy for acid recovery with operational simplicity and energy efficiency. This study utilized adenine’s basic sites to anchor phytic acid (IP6) and prepared phytic acid-doped adenine-modified sulfonated poly ether ether ketone (SPEEK x A/IP6) membranes with varying adenine substitutions. The acid-base crosslinking among adenine, phytic acid, and sulfonic acid groups enhances membrane mechanical characteristics and dimensional stability. The breaking strength increased 8 %–22 % relative to the pure SPEEK. The interactions between phytic acid and SO 3 H groups with adenine promote proton transport, while the large planar cationic structure of protonated adenine enhances membrane permselectivity. The SPEEK-40A/IP6 membrane exhibited superior H + flux (2.16 mmol m −2 s −1 ) and H + /Fe 2+ permselectivity (58.5), which is 1.72 times higher than the original SPEEK and surpasses both ASTOM (38.9) and recent reported membranes. These findings indicate the significant potential of SPEEK- x A/IP6 membranes for acidic wastewater acid recovery.
研究领域:
材料科学
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环境工程
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化学工程
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DOI
高影响因子
JOURNAL OF POWER SOURCES
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2020
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IF 8.247
Wenjie Xu,Jun Long,Jun Liu,Yanlin Wang,Huan Luo,Yaping Zhang,Jinchao Li,Liangyin Chu,Hao Duan
Branched polyfluoro sulfonated polyimide (BPFSPI) membranes with different degree of branching and degree of sulfonation are designed and prepared for application in vanadium redox flow battery (VRFB). The optimized BPFSPI-10-50 membrane exhibits a similar proton conductivity (2.94 × 10 −2 S cm −1 ) as that of the commercial Nafion 212 membrane (3.20 × 10 −2 S cm −1 ) and a much higher membrane selectivity (3.16 × 10 5 S min cm −3 ) than Nafion 212 membrane (0.42 × 10 5 S min cm −3 ). Meanwhile, BPFSPI-10-50 membrane is durable in V(V) + H 2 SO 4 solutions for more than 30 d. Both coulomb efficiency ( CE ) and energy efficiency ( EE ) of BPFSPI-10-50 membrane are higher than those of Nafion 212 membrane ( CE : 94.2–98.9% vs 73.9–94.9%, EE : 68.0–86.9% vs 67.7–77.9%) in VRFB (40–200 mA cm −2 ) test. Besides, BPFSPI-10-50 membrane displays slower self-discharge rate and excellent discharge capacity retention compared to Nafion 212 membrane. Furthermore, the VRFB with BPFSPI-10-50 membrane shows very stable CE and EE (>98% and 76%) over 200 charge-discharge cycles. Accordingly, the BPFSPI-10-50 membrane with superior cost-performance ratio has an outstanding prospect for application in VRFB.
研究领域:
材料科学
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能源技术
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2025
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IF 9
Xiangyang Liu,Jin Wang,Wenyue Huang,Maogang He
Difluoromethane (R32) is a good additive to improve the coefficient of performance (COP) of hydrofluoroolefins (HFOs) which are the next generation of refrigerants. Therefore, it is important to efficiently recover Difluoromethane (R32) from R410A(a blend of 50 % R32 and 50 % pentafluoroethane (R125)) which will be eliminated due to high global warming potential (GWP). In this work, fluorinated UiO-66 was synthesized by replacing the terephthalic acid ligand in UiO-66 with an organic ligand containing fluorocarboxylic acids to enchance the separation performance of mixed matrix membranes (MMMs) as filler, and the effect of the fluorine content of the fluorinated UiO-66 was investigated. In this study, Fluorinated UiO-66/Pebax MMMs were successfully prepared, with the fluorine content tailored by using different ligands. The separation performance increased with the amount of fluorine in the MOFs, namely UiO-66-(CF 3 ) 2 /Pebax > UiO-66-F 4 /Pebax > UiO-66-F 2 /Pebax > UiO-66-F/Pebax > UiO-66/Pebax MMMs. The 20 wt% UiO-66-(CF 3 ) 2 /Pebax achieved an ultra-high P R32 of 979.53 Barrer (397 % of pure Pebax membrane) while maintaining a high ɑ R32/R125 (16.64, 251 % of pure Pebax membrane).The tested results showed that the fluorinated UiO-66/Pebax MMMs sigificantly improved permeability and selectivity for R410A due to the higher R32 solubility caused by C-F…H hydrogen bonding network formed between the fluorine groups and R32 as well as the better sieving ability caused by the decrease in the pore size of UiO-66. The fluorinated MOFs/Pebax MMMs prepared in this work simultaneously achieved better R32/R125 selectivity and R32 permeability,than the exsited membranes, enabling effective separation and recycle R32 from R410A.
研究领域:
化学工程
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材料科学
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环境科学
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膜技术
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制冷剂回收
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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
Yanling Liu,Qihang Cen,Kaiming Fan,Airan Hu,Xu Yuan,Shengji Xia
Efficient removal of natural organic matter (NOM) and organic micropollutants (OMPs) while preserving essential mineral salts is a critical goal of high-quality drinking water production , which has not been satisfyingly achieved by available nanofiltration (NF) membranes. In this study, a facile modification strategy was developed to enhance membrane salt/organics selectivity, purposely utilizing the advantages of sulfonic acid groups including high hydrophilicity, strong acidity and low complexation propensity for divalent cations. The post-treatment using a heated alkaline solution of taurine endowed the membrane with reduced active layer thickness, properly enlarged pore size and more favorable surface characteristics inheriting from grafted sulfonic acid groups. Compared to the control one, the optimal modified membrane exhibited a more than doubled water permeance and significantly reduced rejections of Ca 2+ and Mg 2+ , while maintaining a high removal capacity for OMPs. The membrane superiority in the rejection selectivity between mineral salts and NOM was further demonstrated for natural surface water treatment, which outperformed a variety of commercial NF membranes. Improved dual resistance to Ca 2+ -involved organic fouling and scaling was also achieved by the sulfonic acid functionalized membrane with a higher passage of Ca 2+ . This study provides insights on the fit-for-purpose enhancement of membrane performance for more efficient water treatment.
研究领域:
环境科学
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水处理
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膜技术
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化学工程
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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）