Frontiers in Chemistry
·
2020
·
IF 3.693
Wang Jingwen,Wan Ying,Yue Siyang,Ding Jiaqi,Xie Pengchao,Wang Zongping
UV/persulfate (UV/PS) could effectively degrade algal cells and micro-organic pollutants. This process was firstly applied to remove Microcystis aeruginosa (M. aeruginosa) and 2,4,6-trichlorophenol (TCP) simultaneously in bench scale. Algal cells can be efficiently removed after 120 min reaction accompanied with far quicker removal of the coexisted TCP, which could be totally removed within 5 min in the UV/PS process. Both SO4•- and HO• were responsible for algal cells and TCP degradation, while SO4•- and HO• separately dominated TCP degradation and algal cells removal. Apart from the role of radicals (SO4•- and HO•) for algal cells and TCP degradation, UV also played a role to some extent. Increased PS dose (0–4.5 mM) or UV intensity (2.71–7.82 mW/cm2) could enhance the performance of the UV/PS process in both TCP and algae removal. Although some intracellular organic matters can be released to the outside of algal cells due to the cell lysis, they can be further degraded by UV/PS process, which was inhibited by the presence of TCP. This study suggested the good potential of the UV/PS process in the simultaneous removal of algal cells and micro-organic pollutants.
研究领域:
环境科学
·
水处理工程
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产品关联
DOI
PubMed
高影响因子
WATER RESEARCH
·
2019
·
IF 7.913
Yuan Yuan,Wei Zhao,Zicheng Liu,Chen Ling,Changqing Zhu,Fuqiang Liu,Aimin Li
The efficient recovery of heavy metals from complexed wastewater is an essential but challenging task. In this study, a novel low-Fe(III) driven UV/Air process (LFUA) was developed to break the strong complexation between ethylenediamine tetracetic acid (EDTA) and heavy metal ions (HMIs) and enable the enhanced recovery of HMIs via chelating resin adsorption (CRA). The inside mechanism of the LFUA process includes: 1) displacement of HMIs from HMI-EDTA complexes by Fe(III); 2) direct photolysis of Fe(III)-EDTA through a ligand-to-metal charge transition reaction (LMCT) and indirect photolysis of EDTA by HO 2 ·/O 2 · - . The iron dosage was orders of magnitude lower than that previously reported, due to the Fe(II)/Fe(III) redox cycle in the LFUA process. Fe(II) formed during the LMCT reaction of Fe(III)-EDTA was oxidized back to Fe(III) by O 2 and HO 2 ·, and the reformed Fe(III) was then recombined with EDTA to sustains the LMCT reaction. EDTA was completely removed in 20 min at a molar ratio of Fe(III)/EDTA = 0.05. In addition, following the LFUA process, the adsorption amounts of various HMIs onto D463 resin were at least two orders of magnitude higher than those reported using the direct adsorption process. Employing the integrated technique of LFUA + CRA enabled the efficient removal of up to 64.5 mg/L of Cu(II) from inlet wastewater, and residual Cu(II) was below 0.5 mg/L. The results of desorption experiments showed that over 90% of Cu(II) was recovered, and the desorption solution had a Cu concentration of 2.1 g/L and purity of 99%. Furthermore, the economic and practical feasibility of using the combined process of LFUA + CRA was analyzed to substantiate that the technique is highly efficient and clean (produces no harmful sludge). Therefore, it is an appropriate and practical process in removing HMIs-EDTA complexes and recovering HMIs from wastewater.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
PubMed
高影响因子
CHEMOSPHERE
·
2018
·
IF 4.427
Huiwang Dai,Shuying Xu,Jianxin Chen,Xiaozeng Miao,Jianxi Zhu
Oxalate enhanced mechanism of Fe 3 O 4 @γ-Fe 2 O 3 was developed to provide novel insight into catalytic process regulation of iron oxide catalysts in heterogeneous UV-Fenton system. And the iron oxide composite of Fe 3 O 4 @γ-Fe 2 O 3 was characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), fourier transform infrared (FTIR) spectroscopy and nitrogen adsorption-desorption isotherms. The results showed that large amount of iron could be leached from catalyst in the presence of oxalate, which promoted the homogeneous UV-Fenton reactions in solution. Orange II degradation could be significantly enhanced with the increase of the ratio of homogeneous UV-Fenton process to heterogeneous UV-Fenton process. The optimum concentration of oxalate determined by experiment was 0.5 mM in oxalate enhanced heterogeneous UV-Fenton system. On this condition, the pseudo-first-order rate constant value of Orange II degradation was 0.314 min −1 , which was 2.3 times as high as that in heterogeneous UV-Fenton system. The removal rates of color and TOC were 100% and 86.6% after 20 min and 120 min treatment, respectively. In addition, the iron ions in solution could be almost completely adsorbed back to the catalyst surface in later degradation stages of Orange II. During the recycle experiments, the results showed that the increase of pH in solution and the sorption of intermediates on the catalyst surface would hinder oxalate enhanced process and lead to a decrease of degradation rate of Orange II in oxalate enhanced heterogeneous UV-Fenton system.
研究领域:
环境科学
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催化化学
✓ 已验证
DOI
高影响因子
POLYMER ENGINEERING AND SCIENCE
·
2025
·
IF 3.2
Binzhi Wang,Yuewen Huang,Bin Wang,Ruixiang Zhou,Feng Wang,Hui Liu
In this study, an N, N-dimethyl-p-toluidine/benzoyl peroxide redox initiation system was used to synthesize a series of silicone-modified UV-curable acrylic pressure-sensitive adhesives (PSAs) via bulk polymerization. The oxidizing and reducing agents were added separately but simultaneously into a mixture of monomers. The impact of varying monomer content on the PSA's properties, as well as the influence of organosilicon incorporation on water and aging resistance, was evaluated through 180° peel strength and initial adhesion tests. The results demonstrated that the PSA without organosilicon modification exhibited a maximum peel strength of 7.21 N/25 mm and an initial adhesion of 8.41 N/25 mm. Although the introduction of the organosilicon structure reduced both peel strength and initial adhesion, it notably improved the PSA's water resistance and aging resistance. Highlights Synthesis without solvent using redox initiator system. UV-cured system to enhance molecular weight and adhesion. Introduction of silane structure to improve water and aging resistance. Adhesion performance testing on different substrates (PET and BOPP).
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2020
·
IF 9.038
Xiaoxiao Zhang,Zhonglin Chen,Jing Kang,Shengxin Zhao,Binyuan Wang,Pengwei Yan,Fengxia Deng,Jimin Shen,Wei Chu
In this study, kinetics, influencing factors and potential mechanisms involved in the degradation of chloral hydrate (CH) by UV/peroxymonosulfate (PMS) process were demonstrated. The degradation rate of CH could reach 89.6% by UV 254 /PMS process, significantly exceeding UV 300 /PMS (0.7%), UV 350 /PMS (6.3%), UV 254 direct photolysis (9.0%) and PMS alone (0.0%) processes. CH degradation in UV 254 /PMS system followed pseudo first-order degradation kinetics with an apparent rate constant of 0.186 min −1 , which was suppressed by Cl − and HCO 3 − . The optimal pH for CH degradation was around 5.0. Direct mineralization accounted for the CH degradation in UV/PMS system. Interestingly, the addition of PMS at the neutral condition before UV irradiation transferred CH into trichloroacetic acid (TCAA). The transformation efficiency of CH into TCAA at 10 min was enhanced from 2.17%–40.38% with the elevation of initial pH from 7.0–8.0. The subsequent exposure of UV lamps ceased the transformation of CH into TCAA and facilitated the direct mineralization of CH, but it did not work in the refractory TCAA degradation. Finally, it was revealed that HO predominantly participated CH degradation in UV/PMS process, while O 2 − was responsible for the transformation of CH into TCAA by addition of PMS before UV irradiation.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2018
·Vol. 20
·期 18
·12808-12816
·
IF 3.906
Zhiyong Li,Xiaoqing Yuan,Ying Feng,Yongkui Chen,Yuling Zhao,Huiyong Wang,Qingli Xu,Jianji Wang
Photo-induced conductivity modulation of stimuli-responsive materials is of great importance from the viewpoint of fundamental research and technology. In this work, 5 new kinds of azobenzene-based photo-responsive ionic liquids were synthesized and characterized, and UV/vis light modulation of their conductivity was investigated in an aqueous solution. The factors affecting the conductivity modulation of the photo-responsive fluids, such as photo-isomerization efficiency, photo-regulation aggregation, concentration and chemical structure of the ionic liquids, were examined systematically. It was found that the conductivity of the ionic liquids in water exhibited a significant increase upon UV light irradiation and the ionic liquids with a shorter alkyl spacer in the cation showed a more remarkable photo-induced conductivity enhancement with a maximum increase of 150%. In addition, the solution conductivity was restored (or very close) to the initial value upon an alternative irradiation with visible light. Thus, the solution conductivity can be modulated using alternative irradiation with UV and visible light. Although the reversible photo-isomerization of the azobenzene group under UV/vis irradiation is the origin of the conductivity modulation, the photo-regulated aggregation of the ionic liquid in water is indispensable for the maximum degree of conductivity modulation because UV irradiation can weaken, even break the aggregated cis-isomers of the ionic liquids in an aqueous solution.
研究领域:
材料科学
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化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
WATER RESEARCH
·
2023
·
IF 12.8
Xuecong Qian,Shilong Wang,Haijun Cheng,Ziye Jia,Da Wang,Yandong Xie,Jinhao Duan,Yu Tian,Jun Ma
The oxidation kinetics of Mn(II) by free chlorine is relatively low under near-neutral pH conditions which limits the Mn removal efficiency in drinking water treatment. Therefore, this study investigated the oxidation efficiency of Mn(II) by the UV-enhanced chlorination (UV/chlorine) system and identified the responsible reactive radical species. The results show that the oxidation kinetic of Mn(II) was greatly enhanced by the UV/chlorine system under near-neutral pH or even acidic conditions. The pseudo-first-order reaction rate of Mn(II) at pH 8.0 (within the first 20 min) increased from 2.60 × 10 −5 s −1 to 3.41 × 10 −4 s −1 . Based on the scavenging experiments and the steady-state kinetic modeling, ClO · and ClO 2 , whose steady-state concentration (∼10 −10 M and ∼10 −9 M, respectively at pH 8.0) was at least 4 orders of magnitude higher than that of HO · and Cl · , were recognized as the dominant reactive species contributing to the oxidation of Mn(II). Kinetic model calculations indicate that the contribution of ClO · to the oxidation of Mn(II) was consistently maintained above 70 %, and ClO 2 also played an important role in the oxidation of Mn(II) especially under acidic and alkaline conditions. In addition, the background components of HCO 3 − and Cl − had negligible influence on the oxidation efficiency because they barely changed the concentration of the ClO · and ClO 2 . This study first demonstrates the important role of ClO 2 in the oxidation of Mn(II) in the UV/chlorine system, and the possible role of ClO 2 in the degradation of some organic pollutants needs to be carefully evaluated in the future.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL TECHNOLOGY
·
2023
·
IF 2.8
Na Sun,Xianglian Wang,Zhanmeng Liu
In this study, electrochemically generated free chlorine (EC/Cl2) was activated by UV irradiation with a light emitting diode (LED) lamp at 275 nm to degrade acetaminophen (AAP, 2 μM) in aqueous solution. The potential at a RuO2-IrO2/Ti plate anode was set at 1.5 V vs. the Ag/AgCl electrode. Chlorine was in situ generated in the presence of Cl杴 at the anode and then it was transformed into various active species such as 晑OH and reactive chlorine species (RCS) under UV-LED irradiation. The degradation of AAP was investigated using batch tests, evaluating the influence of different experimental conditions such as NaCl concentration, phosphate buffer saline concentration, irradiation time and solution pH, keeping constant the UV-LED power and temperature. Results show that AAP could be completely degraded by the hybrid process with a high mineralization ratio (73%), and the degradation process followed a pseudo-first-order kinetics. The value of the Electric Energy per Order (EEO) = 1.272 kWh m杴3 order?, which is lower than the energy consumption of some other UV-based processes for AAP degradation. Adding 1 mM HCO3杴 ions slightly decreased the rate of AAP degradation. Luminescent bacteria experiment revealed that the acute toxicity of the reacted solution could be greatly reduced and the ecological risk was effectively abated. The scavenging assay shows that RCS plays a key role in the AAP degradation. The intermediate products were identified, and possible degradation routes were proposed. The system can advantageously replace conventional UV mercury lamp based ones in the degradation of microorganic pollutants.
研究领域:
环境科学
·
水处理工程
·
光催化降解
✓ 已验证
DOI
PubMed
高影响因子
CHEMOSPHERE
·
2018
·
IF 4.427
Lingfei Ma,Chaoyi Wang,Haipu Li,Fangyuan Peng,Zhaoguang Yang
Geosmin (GSM) and 2-methylisoborneol (2-MIB) are two common odor compounds in drinking water . In this paper, the performance of UV/chlorine was compared with that of chlorine and UV to degrade GSM (100 ng L −1 ) and 2-MIB (100 ng L −1 ) in water. UV/chlorine was further exploited, and a steady-state kinetic model was used to conduct a detailed study on efficiency, rate, reactive species and pathway. The results showed that UV/chlorine greatly could improve the removal ratio to 90% within 5 min, from approximately 20% with only UV or dark chlorine in 60 min. The removal ratio and rate depended on UV light intensity , free chlorine dosage, reaction time and water quality parameters (e.g. pH, concentrations of HCO 3 − and Cl − ). Among these factors, the first two obviously could accelerate the rate and increase the ratio. The degradation was also significantly improved in an acidic condition, while alkaline conditions and HCO 3 − had inhibitory effects, and Cl − created no difference. Contributions of OH and Cl to the degradation of 2-MIB and GSM were further revealed, and OH was found to be the most important reactive species. In the UV/chlorine process, 6 degradation byproducts of 2-MIB, including 1 alcohol, 2 ketones, and 3 olefins , were identified, and 14 degradation byproducts of GSM, including 6 ketones, 1 aldehyde, 2 alcohols, 3 naphthenes , and 2 olefins, were found by using solid-phase microextraction coupled to gas chromatography-mass spectrometry. The possible degradation pathways of GSM and 2-MIB in UV/chlorine thus were proposed.
研究领域:
环境科学
·
饮用水处理
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产品关联
DOI
PubMed
高影响因子
FIRE AND MATERIALS
·
2017
·Vol. 42
·期 1
·99-108
·
IF 1.352
Xiaomeng Wang,Xueqing Liu,Sha Peng,Panrui Peng,Liyong Zou,Jia Chen,Jiyan Liu
Summary A novel phosphorus-containing acrylate monomer (AOPA) was synthesized starting from 2-methy-2,5-dioxo-1,2-oxaphospholane and hydroxyethyl acrylate. The structure of AOPA was characterized with FTIR and 1 H NMR. AOPA shows good compatibility with polyethylene glycol diacrylate (PEGDA) and can polymerize with PEGDA under UV light irradiation at different mass ratios to form membranes with high transparency (above 88.9% of light transmittance in the range of 400-800 nm) and flexibility. Incorporating 20 wt% of AOPA in PEGDA reduced the total heat release and peak rate by 50.3% and 38.4%, respectively, as measured by micro combustion calorimeter. The membrane containing 40 wt% of AOPA with 0.4 mm thickness can pass the UL94 V0 rating, and limiting oxygen index reaches 33.4%. TG-FTIR and SEM-EDX analysis show that the presence of AOPA depresses the thermal degradation and promotes the char formation.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2023
·Vol. 140
·期 44
·e54628
·
IF 3
Xiaoyu Zhang,Yuqing Zhang,Peiyao Li,Ruotong Wang,Binghao Ma,Fanglei Zeng,Qitu Zhang,Hongyan Dai,Ning Li
In order to improve the problems of traditional self-healing polyurethane coating, such as harsh curing and repair conditions, poor hydrophobicity, thermal stability and human affinity, the prepolymer was synthesized by bio-based polyol castor oil (CO), self-made alkyl aryl modified silicone polyol (Si OH) and isophorone diisocyanate (IPDI), and dimethylglyoxime (DOU) was used as chain extender containing dynamic imine bond, methacrylic acid 2-(tert-butylamino)ethyl ester (MABE) was used as a capping agent containing acrylate and high steric hindrance amino structure, and a UV curable room temperature repair bio-based poly(siloxane-urethane) coating (PUESi) was prepared by stepwise polymerization. In this article, the effect of the amount of DOU on the properties of PUESi was studied. The results showed that PUESi with different dosages of DOU could achieve self-healing at room temperature. The maximum repair efficiency of full cut could reach 91.8%, and the scratch repair efficiency could reach 99.3%; The contact angle meter and synchronous thermal analyzer proved that the introduction of Si OH significantly improved the hydrophobicity, oil repellency and thermal stability of PUESi. The water contact angle increased from 78° to 104°, the oil contact angle increased from 63° to 91°, and the 5% thermal decomposition temperature increased from 179 to 196°C. The coating has broad application prospects in the fields such as antifouling and anticorrosion, building material protection, and automotive instruments.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Ying Xu,Zhiwen He,Shuili Yu,Lei Li,Luyang Cai,Peng Yi
Recently, the heterogeneous advanced reduction processes (ARPs) for bromate (BrO 3 - ) degradation have attracted considerable attention due to its stable performance and easy combination with UV disinfection. In this study, a UV/TiO 2 -Bi advanced reduction process (ARP) was established for BrO 3 - removal without adding external sacrificial agents. In the UV/TiO 2 -Bi ARP, Bi nanoparticles (NPs) doped on the TiO 2 acted as hole trapping centers, while TiO 2 NPs were used as reduction centers for the reduction of BrO 3 - , which enhanced the charge carrier separation. The UV/TiO 2 -Bi-1% ARP exhibited the highest BrO 3 - removal rate without the addition of sacrificial agents in the reaction solution compared to UV/TiO 2 ARP and the UV/TiO 2 -Bi ARP at other Bi/Ti ratios. The result of 72% removal of 200 µg/L BrO 3 - at 60 min by 0.2 g/L TiO 2 -Bi-1% in tap water at pH 6.8 and 7.71 mg/L dissolved oxygen (DO) demonstrates the promising potential of the UV/TiO 2 -Bi ARP for the removal of BrO 3 - in practical applications. Compared to the 99.5% removal in deionized (DI) water at 60 min, lower BrO 3 - reduction in tap water was likely attributed to the consumption of photo-generated electrons by NO 3 – and the adsorption of natural organic matter on the surface of TiO 2 -Bi-1% nanocomposites. The study provides not only a novel BrO 3 - removal system with good photo-reduction performance, but also some guidance for the influence of constituents in raw water on the treatment of BrO 3 - .
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）