SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Chenghong Qiang,Nan Li,Shixiang Zuo,Zhimin Guo,Wei Zhan,Zhengping Li,Jiangquan Ma
Seeking active and low-cost cocatalysts is a vital task for solving the sluggish kinetics of photocatalysis process in environmental management. Herein, we report a novel and high-efficiency crystallized RuTe 2 cocatalyst, and loaded it onto black TiO 2 to form photocatalytic heterostructure (denoted as RuTe 2 /B-TiO 2 ) for diclofenac (DCF) degradation. To the best of our knowledge, the RuTe 2 as a cocatalyst for photocatalysis based on swift electron capture has not been documented yet. The degradation efficiency of DCF over 0.5% RuTe 2 /B-TiO 2 reached 95.2% for 120 min, which is 1.2 times higher than that of pure B-TiO 2 . In addition, the effects of different calcination temperatures, catalyst amounts, DCF concentrations and solution pH of the as-prepared catalysts were also investigated in depth. Spectroscopy/electrochemistry showed that 0.5% RuTe 2 /B-TiO 2 exhibited a narrower band gap, more active sites and better electrical conductivity than pure B-TiO 2 . Experiments with trapping agents have shown that O 2 – was the main active substance under irradiation. Furthermore, intermediates for the photodegradation of DCF were detected by liquid chromatography mass system (LC-MS) and density functional theory (DFT) calculations. Finally, the degradation pathway was rationalized and a possible photocatalytic mechanism for 0.5% RuTe 2 /B-TiO 2 was proposed.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
WATER RESEARCH
·
2021
·
IF 11.236
Jinbin Lin,Jing Zou,Hengyu Cai,Yixin Huang,Jiawen Li,Junyang Xiao,Baoling Yuan,Jun Ma
In this study, a commonly used reducing agent, hydroxylamine (HA), was introduced into Fe(II)/PAA process to improve its oxidation capacity. The HA/Fe(II)/PAA process possessed high oxidation performance for diclofenac degradation even with trace Fe(II) dosage (i.e., 1 μM) at pH of 3.0 to 6.0. Based on electron paramagnetic resonance technology, methyl phenyl sulfoxide (PMSO)-based probe experiments and alcohol quenching experiments, Fe IV O 2+ and carbon-centered radicals (R-O • ) were considered as the primary reactive species responsible for diclofenac elimination. HA accelerated the redox cycle of Fe(III)/Fe(II) and itself was gradually decomposed to N 2 , N 2 O, NO 2 − and NO 3 − , and the environmentally friendly gas of N 2 was considered as the major decomposition product of HA. Four possible degradation pathways of diclofenac were proposed based on seven detected intermediate products. Both elevated dosages of Fe(II) and PAA promoted diclofenac removal. Cl − , HCO 3 − and SO 4 2− had negligible impacts on diclofenac degradation, while humic acid exhibited an inhibitory effect. The oxidation capacity of HA/Fe(II)/PAA process in natural water matrices and its application to degrade various micropollutants were also investigated. This study proposed a promising strategy for improving the Fe(II)/PAA process and highlighted its potential application in water treatment.
研究领域:
环境科学
·
水处理技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2022
·
IF 11.357
Yixin Huang,Jing Zou,Jinbin Lin,Haoyu Yang,Mengyun Wang,Jiawen Li,Wei Cao,Baoling Yuan,Jun Ma
The activation of peroxydisulfate (PDS) by organic compounds has attracted increasing attention. However, some inherent drawbacks including quick activator decomposition and poor anti-interference capacity limited the application of organic compound-activated PDS. It was interestingly found that 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonate) (ABTS) could act as both activator and electron shuttle for PDS activation to enhance diclofenac (DCF) degradation over a pH range of 2.0–11.0. Multiple reactive species of ABTS•+, •OH, and SO4•– were generated in the PDS/ABTS system, while only ABTS•+ and •OH directly contributed to DCF degradation. ABTS•+, generated via the reactions of ABTS with PDS, SO4•–, and •OH, was the dominant reactive species of DCF degradation. No significant decomposition of ABTS was observed in the PDS/ABTS system, and ABTS acted as both activator and electron shuttle. Four possible degradation pathways of DCF were proposed, and the toxicity of DCF decreased after treatment with the PDS/ABTS system. The PDS/ABTS system had good anti-interference capacity to common natural water constituents. Additionally, ABTS was encapsulated into cellulose to obtain ABTS@Ce beads, and the PDS/ABTS@Ce system possessed excellent performance on DCF degradation. This study proposes a new perspective to reconsider the mechanism of activating PDS with organic compounds and highlights the considerable contribution of organic radicals on contaminant removal.
研究领域:
环境科学
·
污染控制
·
化学工程
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Ge Song,Yang Zheng,Minghua Zhou
The application of bimetallic catalysts in heterogeneous electro-Fenton (Hetero-EF) is limited due to its poor performance over a wide pH range. In this work, the Hetero-EF/sulfite process was constructed with FeMn@C as the catalyst to improve the degradation of pollutants under neutral pH. The removal efficiency of diclofenac (DCF) (97.8%) was significantly higher than that of Hetero-EF (15.0%) at pH 7, in which the degradation rate constant k was increased by 19.75 times. The existence and transformation process of various active species ( • OH, SO 4 •- , O 2 •- , and 1 O 2 ) in the process were verified by capture experiments and electron paramagnetic resonance (EPR) test. The possible DCF degradation pathway was also proposed. The introduction of sulfite could reduce Fe 3+ and Mn 3+ , promote the Fe(II)/Fe(III) and Mn(II)/Mn(III) cycles, strengthen the generation of active species, and thus promote the degradation of pollutants. The removal efficiency was still maintained 76.6% after five cycles. The Hetero-EF/sulfite process is a simple, feasible, and efficient method to degrade pollutants, which has a broad application prospect.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2018
·
IF 4.427
Xiang Li,Minghua Zhou,Yuwei Pan
Diclofenac sodium (DCF) is frequently detected as a non-steroidal pharmaceutical in the aquatic environment. In this study, the degradation of DCF in two heterogeneous systems, pre-magnetization Fe 0 /H 2 O 2 (Pre-Fe 0 /H 2 O 2 ) and Fe 0 /H 2 O 2 system, was comparably studied. Our findings proved that Pre-Fe 0 could significantly improve the degradation and dechlorination of DCF due to the change of Fe 0 characteristics after pre-magnetization. Compared with Fe 0 /H 2 O 2 process, Pre-Fe 0 /H 2 O 2 process has 2.1–7.0 times higher rate constant for DCF degradation at different H 2 O 2 dosages (0.25–2.0 mM), initial pH (3.0–6.0) and Fe 0 dosages (0.25–1.5 mM). The characterizations by X-ray Photoelectron Spectroscopy and Electron Paramagnetic Resonance confirmed that the enhancement attributed to the increase of Fe 0 corrosion and fast generation of OH . In addition, preliminary degradation mechanism was elucidated by major products identification using UPLC-MS, through which the degradation intermediates, such as 4-hydroxy-diclofenac or 5-hydroxydiclofenac, 2,6-dichloroaniline, phenylacetic acid, 1,3-dichlorobenzene and 2-aminophenylacetic acid were identified. Hydroxylation, decarboxylation , C N bond cleavage and ring-opening involving the attack of OH or other substances, were the main degradation mechanism. Therefore, Pre-Fe 0 /H 2 O 2 process, which does not need extra energy and costly reagents, is an efficient and environmental-friendly process to degrade DCF.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
·
2021
·
IF 7.086
Hua Guo,Zhicheng Xu,Dan Wang,Shiyu Chen,Dan Qiao,Dan Wan,Hao Xu,Wei Yan,Xiaoliang Jin
This work investigates the electrochemical oxidation (EO) of diclofenac (DCF) in water with Ti/Ti 4 O 7 , Ti/Ru–Ir, Ti/Sb–SnO 2 and Ti/PbO 2 electrodes. Scanning electron microscope and X-ray diffraction results suggest that Ti/Ti 4 O 7 has porous stacked surface morphology and Ti/Sb–SnO 2 possesses the smallest grain size. Linear sweep voltammetry test results indicate that PbO 2 has the highest oxygen evolution potential, while Ti/Ti 4 O 7 and Ti/Ru–Ir show better oxygen evolution activity. DCF degradation results reveal that PbO 2 possessed the highest DCF removal ( R DCF = 99.2%) and chemical oxygen demand (COD) removal ( R COD = 97.0%), the fastest COD degradation rate ( k = 0.0275 min −1 , R 2 = 0.964), the lowest specific energy consumption ( EC DCF = 1.81 kWh . g DCF −1 , EC TOC = 6.90 kWh . g TOC −1 ). The toxicity variation of DCF during EO process on PbO 2 is rise first and then to fall. Considering the differences of the four electrodes in residual, conversion and mineralization aspects, mineralization selectivity ( MS ) was proposed to estimate the mineralization inclination of electrodes during EO process, and PbO 2 displays the strongest mineralization inclination ( MS = 0.594). In addition, the possible degradation pathway of DCF on PbO 2 electrode indicates a composite behavior of conversion and mineralization. All of them above indicate the promising application potential of PbO 2 in lower concentration pharmaceuticals and personal care products wastewater treatment . Moreover, MS could be employed as a supplementary index to assess the different inclinations of this composite behavior on various electrodes used for electrochemical treatment of organics in later studies.
研究领域:
环境科学
·
电化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Reaction Chemistry & Engineering
·
2021
·Vol. 6
·期 12
·2411-2424
·
IF 4.239
Shuaiqi Ning,Shuai Mao,Chun Liu,Mingzhu Xia,Fengyun Wang
In this paper, some perovskite catalysts LaFeO3 (LFO) were prepared by using the efficient chelating properties of sodium diethylene triamine pentamethylene phosphonate (DTPMP-2Na) toward metal ions, and the best catalyst LFO-0.1 was selected by using diclofenac sodium as the target pollutant. Then, the influence of different factors (PMS dosage, catalyst dosage, substrate concentration and anion) on the degradation of DCF in a LFO-0.1/PMS system was studied. The catalyst was characterized, and the reaction mechanism of diclofenac (DCF) in the LFO-0.1/PMS system was analyzed. It was concluded that hydroxyl radicals, sulfate radicals and singlet oxygen were produced in the LFO-0.1/PMS system. In the reaction system, singlet oxygen is considered to be the main factor for DCF degradation in this system, and the generation of sulfate radicals is mainly attributed to oxygen vacancies and the electron transfer between Fe3+ and Fe2+. Through the centrifugal recovery of the catalyst to explore its stability, the conclusion is that LFO-0.1 is a stable catalyst. Finally, 15 kinds of oxidation intermediates and products were identified, and the possible degradation pathways of DCF were analyzed, including decarboxylation, dechlorination, C–N cleavage, hydroxylation, ring-closure and ring-opening.
研究领域:
环境科学
·
催化化学
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
·
2021
·
IF 7.086
Jiewen Deng,Hongbin Wang,Yongsheng Fu,Yiqing Liu
Activating peroxides to produce active substances is the key to advanced oxidation processes (AOPs), but this usually requires energy or is accompanied by additional contaminants. In this study, diclofenac (DCF) was effectively removed by peracetic acid (PAA) in phosphate buffer (PBS). According to the results of radical scavenging experiments and electron paramagnetic resonance (EPR), hydroxyl radical (•OH) and organic radicals (i.e., CH 3 C(=O)OO• and CH 3 C(=O)O•) generated from PBS-activated PAA might be the dominant reactive species responsible for DCF degradation. At neutral pH, PBS/PAA system exhibited the best degradation efficiency on DCF. Presence of NO 3 − , SO 4 2− and Cl − had little effect on the removal of DCF, while HCO 3 − and natural organic matter (NOM) significantly inhibited DCF degradation in PBS/PAA system, resulting in the lower degradation efficiency of DCF in natural waters than that in ultrapure water. Finally, four possible degradation pathways, including hydroxylation, formylation, dehydrogenation and dechlorination , were proposed based on the detected reaction products. This study suggests that PBS used to control solution pH should be applied cautiously in PAA-based AOPs.
研究领域:
环境科学
·
化学
✓ 已验证
DOI
PubMed
高影响因子
ENVIRONMENTAL POLLUTION
·
2021
·
IF 8.071
Yan Feng,Zichen Li,Yingying Long,Ning Suo,Zhongwei Wang,Lipin Qiu
Electric and magnetic fields characterized by high efficiency, low consumption and environment-friendly performance have recently generated interest as a possible measure to enhance the performance of the biological treatment process used to remove refractory organics. Few studies have been carried out to-date regarding the simultaneous application of electric and magnetic fields on biofilm process to degrade diclofenac. In this study, 3DEM-BAF was designed to evaluate the electrio-magnetic superposition effect on diclofenac removal performance, kinetics, community structure and synergistic mechanism. The results show that 3DEM-BAF could significantly increase the average removal rate of diclofenac by 65.30 %, 57.46 %, 9.48 % as compared with that of BAF, 3DM-BAF, 3DE-BAF, respectively. The diclofenac degradation kinetic constants and dehydrogenase activity of 3DEM-BAF were almost 6.72 and 2.53 times higher than those of BAF. Microorganisms of 3DEM-BAF in the Methylophilus and Methyloversatilis genera were distinctively enriched, which was attributed to the screening function of electric field and propagation effect of magnetic field. Moreover, three processes were found to contribute to diclofenac degradation, namely electro-magnetic-adsorption, electro-chemical oxidation and electro-magnetic-biodegradation. Thus, the simultaneous application of electric and magnetic fields on biofilm process was demonstrated to be a promising technique as well as a viable alternative in diclofenac degradation enhancement.
研究领域:
环境科学
·
微生物学
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2020
·
IF 9.038
Junlei Zhang,Wei Zhao,Shanshan Wu,Renli Yin,Mingshan Zhu
Advanced oxidation processes (AOPs) based on heterogeneous catalytic activated peroxymonosulfate (PMS) have been becoming alternatives to conventional wastewater treatment technologies to directly degrade chemical contaminants. To build dual/multi redox cycles of different metal ions may be an effective means for better PMS activation. Herein, this study designed Mn 3 O 4 /CuBi 2 O 4 with dual redox cycles of Mn(III)/Mn(IV) and Cu(I)/Cu(II) to activate PMS for efficiently decomposing and mineralizing diclofenac sodium (DCF). Under optimal reaction conditions, DCF (50 mg/L) was degraded totally within 10 min, and TOC removal rate reached up to 74.3%. The possible mechanism of PMS activation by Mn 3 O 4 /CuBi 2 O 4 was proposed, wherein dual redox cycles of Mn(III)/Mn(IV) and Cu(I)/Cu(II) on Mn 3 O 4 /CuBi 2 O 4 effectively facilitated PMS activation to generate · O 2 − , 1 O 2 , SO 4 · − and · OH, which was responsible for DCF degradation. Moreover, combined with degraded products detected by high resolution liquid chromatography coupled to mass spectrometry and corresponding toxic assessment results, the possible degradation pathways of DCF were proposed and the relative toxicity of degraded products was evaluated. This work may be useful for developing stronger heterogeneous activators of PMS to construct more efficient AOPs for purifying wastewater.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2017
·
IF 6.065
Weirui Chen,Xukai Li,Yiming Tang,Jialu Zhou,Dan Wu,Yin Wu,Laisheng Li
A flexible catalyst, Fe-Cu-MCM-41, was employed to enhance diclofenac (DCF) mineralization and inhibit bromate formation in catalytic ozonation process. Greater TOC removal was achieved in Fe-Cu-MCM-41/O 3 process (78%) than those in Fe-MCM-41/O 3 (65%), Cu-MCM-41/O 3 (73%) and sole ozonation (42%). But it was interesting that both Cu-MCM-41/O 3 and Fe-MCM-41/O 3 achieved 93% bromate inhibition efficiency, only 71% inhibition efficiency was observed in Fe-Cu-MCM-41/O 3 . Influence of pH, TBA/NaHSO 3 and detection of by-products were conducted to explore the mechanism. By Pyridine adsorption–IR and XPS, a relationship was found among activity of catalysts, Lewis acid sites and electron transfer effect between Fe (II/III) and Cu (I/II). Fe-Cu-MCM-41 promoted ozone decomposition to generate OH, which accounted for enhanced DCF mineralization. The consumption of aqueous O 3 also suppressed the oxidative of Br − and HBrO/Br − . More HBrO/BrO − accumulated in catalytic ozonation process and less bromate generated. Bromate formation in Fe-Cu-MCM-41/O 3 process was sensitive with pH value, the acidic condition was not favor for bromate formation. Both DCF mineralization and bromate inhibition were influenced by surface reaction. Moreover, Fe-Cu-MCM-41 showed excellent catalytic performance in suppressing the accumulation of carboxylic acid, especially for oxalic acid. Nearly no oxalic acid was detected during Fe-Cu-MCM-41/O 3 process.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Jieling Song,Wen Liu,Zhaokun Xiong,Bo Lai,Rongfu Huang
This study utilized tetrapolyphosphate (TPP) as the electrolyte in the electro-Fenton (EF) system to efficiently generate reactive oxygen species (ROS) for effective degradation of diclofenac sodium (DCF) by activating dissolved molecular oxygen without aeration. The results indicated that the EF-TPP process produced a higher concentration of Fe(II) ions but a lower concentration of total iron than those concentrations in the regular EF-Na 2 SO 4 process, resulting in the higher degradation efficiency of the former system without producing iron sludge. It was found both hydroxyl ( OH) and superoxide radicals (O 2 − ) are primary reactive species in the EF-TPP system. The EF-TPP system produced a much higher amount of OH (3.886 μmol/L) than that of the EF-Na 2 SO 4 system (0.042 μmol/L). In addition, results of density functional theory (DFT) calculations and characterization experiments revealed the reaction pathway of dissolved molecular oxygen with Fe-TPP complexes, which are primarily present as [Fe(TPP)(H 2 O) 2 ] − and [Fe(TPP) 2 ] 4− in the EF-TPP system. These results indicated that both speciation of Fe-TPP complexes can effectively activate molecular oxygen to generate ROS. DCF degradation pathways were proposed by identifying the formed byproducts. Overall results indicated the electrolyte TPP in the EF-TPP system induces the slow release of iron ions, the formation of Fe-TPP complex to stabilize the Fe(II) in the neutral pH condition, and the enhanced activation of dissolved molecular oxygen via one-electron transfer pathway.
研究领域:
环境科学
·
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）