Science China-Technological Sciences
·
2024
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IF 4.4
Niu WenXing,Zhao XinRui,Yuan Min,Hou ZhiGuo,Liu Lei,Xu Hong,Dong JinXiang
We studied different long-chain ammonium ions intercalated zirconium phosphate α-ZrP, methylamine intercalated ZrP (MA-ZrP), tetramethylammonium hydroxide intercalated ZrP (TMAH-ZrP), dodecyltrimethylammonium bromide intercalated ZrP (DTAB-ZrP), and stearyl trimethyl ammonium bromide intercalated ZrP (STAB-ZrP) as grease co-additives in combination with isobutylene sulfide (SIB). The grease with co-additives displayed excellent extreme-pressure and anti-wear performance. Moreover, the combination of the longest chain ammonium ion intercalated zirconium phosphate, STAB-ZrP/SIB, had the best tribological properties. In comparison to α-ZrP, the advantage of STAB-ZrP was that it did not form a large area of the dense physical film like α-ZrP on the worn surface, but rather gave the SIB a chance to contact with the fresh metal surface to generate a chemical film. Therefore, the sub-micron physical film and nanoscale chemical film always exist side by side on the contact surface during the friction process. This intercalated α-ZrP/SIB additive has great potential for use in harsh operating conditions.
研究领域:
材料科学
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摩擦学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Membranes
·
2022
·Vol. 12
·期 8
·814
·
IF 4.562
Liankai Gu,Yonghao Zhang,Weiqing Han,Kajia Wei
Membrane fouling and regeneration are the key issues for the application of membrane separation (MS) technology. Reactive electrochemical membranes (REMs) exhibited high, stable permeate flux and the function of chemical-free electrochemical regeneration. This study fabricated a micro-filtration REM characterized by a PbO2layer (PbO2-REM) to investigate the electro-triggered anti-fouling and regeneration progress within REMs. The PbO2-REM exhibited a three-dimensional porous structure with a few branch-like micro-pores. The PbO2-REM could alleviate Humic acid (HA) and Bisphenol A (BPA) fouling through electrochemical degradation combined with bubble migration, which achieved the best anti-fouling performance at current density of 4 mA cm−2with 99.2% BPA removal. Regeneration in the electro-backwash (e-BW) mode was found as eight times that in the forward wash and full flux recovery was achieved at a current density of 3 mA cm−2. EIS and simulation study also confirmed complete regeneration by e-BW, which was ascribed to the air–water wash formed by bubble migration and flow. Repeated regeneration tests showed that PbO2-REM was stable for more than five cycles, indicating its high durability for practical uses. Mechanism analysis assisted by finite element simulation illustrated that the high catalytic PbO2layer plays an important role in antifouling and regeneration.Keywords:membrane fouling;reactive electrochemical membrane;PbO2catalytic layer;antifouling;regeneration
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Lubricants
·
2024
·Vol. 12
·期 5
·167
·
IF 3.1
Xiangyu Ge,Xiaodong Wu,Qiuyu Shi,Yanfei Liu,He Liang
This work studied the influence of the voltage parameters on the friction and superlubricity performances of LiPF6-based ionic liquids (ILs). The results show that the voltage direction and magnitude greatly affected the friction performances of ILs and that macroscale superlubricity can be achieved with a stimulation of −0.1 V. The surface analysis and experiment results indicate that the voltage magnitude influences the coefficient of friction (COF) by determining the types of substances in the tribochemical film formed on the ball, while the voltage direction influences the COF by affecting the adsorption behavior of Li(PEG)+ions on the ball. At −0.1 V, the cation group Li(PEG)+adsorption film and FeOOH-containing tribochemical film contribute to friction reduction. The formation of FexOywithin the tribochemical film results in an increase in friction at −0.8 V. The limited adsorption of Li(PEG)+ions and the formation of FexOycontribute to the elevated COF at +0.1 V. This work proves that the friction performances of LiPF6-based ILs could be affected by voltage parameters. A lubrication model was proposed hoping to provide a basic understanding of the lubrication mechanisms of ILs in the electric environment.
研究领域:
材料科学
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摩擦学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
WATER RESEARCH
·
2024
·
IF 11.4
Jiazhou He,Jieqin Zhou,Kui Yang,Liang Luo,Pan Wang,Zhiwei Wang,Jinxing Ma
Recovering ammonia from waste streams ( e.g. , urine) is highly desirable to reduce natural gas-based NH 3 production and nitrogen discharge into the water environment. Electrochemical membrane stripping is an attractive alternative because it can drive NH 4 + transformation to NH 3 via cathodic OH − production; however, the conventional configurations suffer from relatively low ammonia recovery (<80 %) and significant acid/material usage for ammonia adsorption. To this end, we develop a novel stack system that simply uses an oxygen evolution reaction to in-situ produce acid from water, enabling chemical-free ammonia recovery from synthetic urine. In batch mode, the percentage removal and recovery increased respectively from 74.5 % to 97.9 % and 81.8 % to 92.7 % when the electrode pairs increased from 2 to 4 in the stack system. To address the gas-sparging issue that deteriorated ammonia recovery in continuous operation, pulsed electric field (PEF) mode was applied, resulting in ∼100 % recovery under optimized conditions. At an ammonia removal rate of 35.1 g-N m −2 h −1 and electrical energy consumption of 28.9 kWh kg-N −1 , our chemical-free system in PEF mode has achieved significantly higher ammonia recovery (>90 %) from synthetic urine. The total cost to recover 1 kg of NH 3 –N from real human urine was $15.9 in the proposed system. Results of this study demonstrate that this novel approach holds great promise for high ammonia recovery from waste streams, opening a new pathway toward sustainable nitrogen management.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
PubMed
高影响因子
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
·
2023
·
IF 7.8
Jifang Yu,Jianbing Wang,Huijun Yu,Jianwei Hu,Longxin Jiang,Weiyi Wang
Naphthols (NAPs), commonly used phenolic compounds, have significant impact on environmental risk and human health, necessitating advanced treatment methods for their degradation. In this study, a Ti 4 O 7 reactive electrochemical membrane (REM) was developed for the electrochemical oxidation of NAPs. The Ti 4 O 7 REM presented a porosity of 42.18 ± 2.3% and a median pore diameter of 1.21 µm. High permeability (846 LMH bar −1 ) was achieved at relatively low transmembrane pressure and resulted in a convection-enhanced rate constant for Fe (CN) 6 4- oxidation of 1.7 × 10 −4 m/s. The increase in current density and decrease in plate spacing had a positive influence on NAPs degradation. The TOC removal efficiencies of 1-naphthol (1-NAP) and 2-naphthol (2-NAP) were 68.6% and 63.5%, respectively at the current density of 6 mA/cm 2 and plate spacing of 10 mm. Additionally, quantum chemical calculation using density functional theory (DFT) was employed to identify the active sites of NAPs through atom charge and frontier electron density (FED) calculations. Results showed that C14 and C10 were identified as the active sites for 1-NAP, while C9 and C13 were the active sites for 2-NAP. Hydroxyl radical and sulfate radical produced on the electrode surface were the main oxidants for NAPs degradation during the electro-oxidation process. The degradation pathway included hydroxylation , oxygenation, decarbonylation, and ring-open processes, which was in agreement with the theoretical calculations. Furthermore, the quantitative structure-activity relationship (QSAR) predictive model was used to assess the toxicity changes during the electrochemical oxidation process of NAPs, suggesting that the toxicity of intermediates increased at the beginning and significantly reduced at the end. This comprehensive study provides practical and theoretical insights into the application of electrochemical oxidation technique for the reduction of refractory compounds in wastewater.
研究领域:
环境科学
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化学工程
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毒理学
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2021
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IF 10.588
Kui Yang,Xingwei Feng,Hui Lin,Jiale Xu,Cao Yang,Juan Du,Dengmiao Cheng,Sihao Lv,Zhifeng Yang
Herein, we reported a tandem multilevel reactive electrochemical membrane (REM) system was promising for the rapid and complete removal of trace antibiotics from natural waters. Results indicate that a four-stage REM module-in-series system achieved steady over 98% removal of model antibiotic norfloxacin (NOR, 100 μg·L −1 ) from wastewater treatment plant final effluent and surface water with a residence time of 5.4 s, and the electric energy consumption was only around 0.007–0.011 kWh·m −3 . As for the oxidation mechanism , direct electron transfer (DET) oxidation process played an important role in NOR rapid oxidation, enabling the REM system to tolerate various • OH scavenges in natural waters, including natural organic matters, Cl - and HCO 3 - , even at very high concentration levels. Meanwhile, • OH-mediated indirect oxidation process promotes the oxidation and mineralization of NOR. Although the DET-dominated oxidation mechanism makes the REM system cannot achieve the complete mineralization of NOR with residence times of few seconds, the antibacterial activity from NOR was completely eliminated. This REM system featured effective removal performance of trace contaminants with low energy cost and was tolerant to complex waster matrix, suggesting that it could be a powerful supplementary step for wastewater/water treatment.
研究领域:
环境科学
·
水处理工程
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
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2018
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IF 5.116
Jicheng Sun,Qiaoying Wang,Jie Zhang,Zhiwei Wang,Zhichao Wu
In this study, a novel electrochemical membrane filtration (EMF) process was proposed to degrade sulfadiazine (SDZ) in drinking water , and the oxidation mechanisms , kinetics, byproducts and primary impact factors were investigated. In the EMF process, a novel membrane was used as the cathode and two graphite plates were used as anodes. Five oxidation byproducts including 4-OH-sulfadiazine or 5-OH-sulfadiazine, 2-aminopyrimidine, 4-amino- N -carbamimidoyl benzene sulfonamide and 2,5-dihydroxypyrimidine were identified. Possible degradation pathways for SDZ were proposed, and OH and were recognized to be the major reactive oxygen species contributed for SDZ degradation. The degradation of SDZ by EMF followed pseudo-first-order kinetics in batch experiment and the rate constant increased as the applied voltages increased. Compared with the batch experiment, the flow-through mode of EMF slowed SDZ degradation, and the degradation rate also decreased as the flux increased. However, on the base of mass balance calculations more SDZ was degraded in flow-through mode as compared with that in batch experiment. Finally, the degradation of SDZ in natural waters from a municipal drinking water treatment plant was investigated with flow-through mode, and the result shows that the degradation rate (79%) was slightly lower than that obtained for deionized water due to the low conductivity of real-world water systems.
研究领域:
环境科学
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水处理工程
·
化学工程
✓ 已验证
DOI
高影响因子
Lubricants
·
2024
·Vol. 12
·期 5
·146
·
IF 3.1
Shuo Xiang,Xinghao Zhi,Hebin Bao,Yan He,Qinhui Zhang,Shigang Lin,Bo Hu,Senao Wang,Peng Lu,Xin Yang,Qiang Tian,Xin Du
The layered double hydroxide (LDH) has been practically applied in the field of tribology and materials science due to its unique physicochemical properties, weak bonding, flexible structural composition, and adjustable interlayer space. In this work, a series of ultrathin and flexible composition of Ni-Fe LDH samples were prepared via a cost-effective room-temperature co-precipitation process. Then, they were mechanically dispersed into GTL base oil and their lubricating performance were tested by a four-ball tribometer. It is found that the variation of Ni-Fe ratio of Ni-Fe LDH has a great influence on the improvement of lubricating performance of GTL base oil. At the same concentration (0.3 mg/mL), the Ni-Fe LDH with Ni/Fe ratio of 6 was demonstrated to exhibit the best lubricating performance and the AFC, WSD, the wear volume, surface roughness and average wear scar depth decreased 51.3%, 30.8%, 78.4%, 6.7% and 50.0%, respectively. SEM-EDS and X-ray photoelectron spectra illustrated that the tribo-chemical film consisting of iron oxides and NiO with better mechanical properties formed and slowly replaced the physical film, which resists scuffing and protect solid surface from severe collisions.
研究领域:
材料科学
·
摩擦学
✓ 已验证
产品关联
DOI
高影响因子
CARBON
·
2025
·
IF 11.6
Bo Dai,Qian Jia,Bingbing Lai,Xiaoyu Wang,Lizan Wang,Haichao Liu,Wenjing Lou,Xiaobo Wang
To address electrical erosion in rolling bearings of the motor systems of electrical vehicles, this study presents an in situ functionalization of graphene oxide (GO) with an amino-functionalized ionic liquid, [Bmim]PF 6 , resulting in a reduced graphene oxide–ionic liquid composite (rGOIL) with excellent electrical conductivity and outstanding friction-reducing and anti-wear performances. A series of conductive urea-based greases are formulated by optimizing the rGOIL content. The structure and morphology of rGOIL are characterized by FTIR, XRD, Raman spectroscopy, SEM, TEM, and XPS. Tribological tests using an SRV tribometer and electrical erosion evaluation on a bearing test rig show that grease containing 0.5 wt% rGOIL maintains a low and stable friction coefficient (0.102) under a 200 N load at 50 °C, with a 93 % reduction in wear volume compared to conventional polyurea grease. In electrical erosion tests, the bearing vibration amplitude stabilizes at 1.1 mm/s 2 , only 15 % of that measured for the reference grease. XPS and TEM analyses reveal the formation of a tribochemical film consisting of graphene nanosheets, ionically bonded liquid layers, and metal fluorides and phosphates. This film forms a conductive lubrication layer through a synergistic "lubrication–conductivity–lubrication" mechanism, effectively mitigating electrical erosion and enhancing bearing durability.
✓ 已验证
产品关联
DOI
高影响因子
ACS ES&T Engineering
·
2023
·
IF 7.1
Kui Yang,Daoyuan Zu,Zhong Zhang,Jinxing Ma,Zhifeng Yang
A reactive electrochemical membrane (REM) has been identified as an excellent platform in micropolluted water purification due to its rapid mass transfer capability. Unlike traditional flow-by systems, the convection-enhanced REM systems activate the REM’s inner reaction sites, potentially imparting a spatially variable reactivity. Therefore, we explored the spatial scale of micropollutant oxidation in REM. Theoretical and experimental evidence demonstrated that an REM might feature nonuniform oxidation activity along its reaction depth (about hundreds of micrometers). That is, the zone generating •OH was located within a few micrometers beneath the REM surface, i.e., less than 1% of its reaction depth due to the rapid overpotential/potential drop in the REM. The nonuniform reactive character might render the REM of a strong direct electron transfer ability, enabling rapid removal of electron-rich micropollutants even at low potentials. However, unsatisfactory removal of electron-poor micropollutants has been observed, and a higher potential was required to prompt the generation of •OH. These results provide in-depth insight into the spatial scale of nonuniform oxidation of micropollutants in REM, contributing to the analysis of micropollutant oxidation mechanisms and the optimization of the design and operation of REM modules for cost-effective water purification.
研究领域:
环境科学
·
电化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2022
·
IF 10.53
Tahir Maqbool,Quang Viet Ly,Keyou He,Lele Cui,Yangyang Zhang,Mingming Sun,Zhenghua Zhang
Refractory organic matter in different water matrices poses tremendous challenges for treatment processes. The substoichiometric titanium oxide (Ti 4 O 7 ) anode-designed reactive electrochemical membrane (REM) introduced for this critical problem and its performance was comprehensively evaluated in terms of current density, conductivity, membrane flux, total organic carbon (TOC) concentration, and pH using humic acid (HA) as a surrogate refractory organic compound. Increase in membrane flux from 500 to 2000 LMH showed a positive impact on the HA removal. The increase in current density and conductivity improved the mineralization performance. Depending on pH, the induction of electrical current to REM improved the HA removal from 0% to 80% compared to the case without power. It appeared that HA removal was achieved through direct electron transfer , oxidation by hydroxyl radicals (•OH), and electrosorption. The distribution of the three leading phenomena showed electrosorption as the main contributor to HA removal. The noticeable generation of •OH was recorded using electron paramagnetic resonance (EPR), and the structural transformation of HA was confirmed through the blue shift in the major fluorescence peak of HA. The energy consumption per g TOC was recorded to be economical for operation at lab-scale applications and thus highly promising for full-scale consideration. This study showed that REM could remove HA at a medium-level to a higher concentration with extraordinary stability.
研究领域:
环境科学
·
水处理工程
✓ 已验证
DOI
高影响因子
Chem Catalysis
·
2024
·
IF 11.5
Yangyang Zhang,Zhenghua Zhang
The catalyst efficiency-stability trade-off still remains the major challenge for advanced oxidation processes (AOPs). To overcome this challenge, herein, we develop a sustainable and metal-free AOP by an electrified reduced graphene oxide (rGO) membrane in the flow-through electrochemical membrane system, demonstrating efficient degradation of a broader range of water contaminants (>90%), significant reduction of the effluent toxicity (harmless effluent) via the electrochemical activation of peroxymonosulfate (PMS), and long-term stability (>50 h) even in various real water matrices. The external electric field maintains the morphology of rGO and promotes the redox cycle between C–O and C=O groups of rGO at the cathode, with the electrochemical regenerated C–O groups providing sustainable active sites for the formation of rGO-PMS∗, ensuring the long-term stability of the electrified rGO membrane. This work paves the way toward the application of cheap carbonaceous catalysts for effective and sustainable water purification and decontamination.
研究领域:
环境科学
·
材料科学
✓ 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）