CHEMICAL ENGINEERING JOURNAL
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2013
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IF 3.473
Guangyu Zhao,Xiwu Lu,Yi Zhou
The use of combination of air and UV irradiation for organic matters removal has drawn attention since degradation efficiency would be significantly enhanced in the presence of oxygen. Considering the fact that a low-pressure mercury UV lamp (emitting at 254 nm and 185 nm) could dissociate oxygen in gas phase and generate ozone, UV irradiation with addition of ozone enriched air, generated by the same UV lamp, was introduced. This technology was called UV-microO 3 because the concentration of ozone generated by UV irradiation was relatively low (lower than 1 mg L −1 ). The degradation of aniline by UV-aeration and UV-microO 3 processes was comparatively analyzed. It was shown that aniline underwent much faster and more complete degradation in UV-microO 3 process than in UV-aeration system. Hydroxyl radical ( OH) exposure in UV-microO 3 process was 2.46 times of that in UV-aeration system. Furthermore, increasing inlet air flow rate would be of benefit to maintaining high dissolved oxygen (DO) level in UV-aeration system, thus the aniline removal was improved. While concentration of ozone generated by UV irradiation increased at first and then declined as the air flow rate increased from 1.8 L min −1 to 4.8 L min −1 in UV-microO 3 process, and similar trend for aniline removal rate was observed. The contributions of radicals on aniline removal in UV-aeration and UV-microO 3 processes were calculated to be 23.1% and 67.7%. The formation of 4-aminophenol, 4-Hydroxydiphenylamine, azobenzene and 4-Phenylazophenol was observed as the major intermediates in UV-aeration and UV-microO 3 processes, mechanism of aniline degradation was proposed based on experimental evidence.
研究领域:
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
CHEMOSPHERE
·
2023
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IF 8.8
Tianyuan Xu,Ting Chen,Zhenhua Chen,Yijun Cao,Yaowen Xing,Xiahui Gui
A photochemical system combining iron (hydr)oxides and oxalate (Ox) shows application prospects in wastewater treatment due to the abundance of reactive oxygen species (ROS) generation. Nevertheless, it is a challenge to the investigate photochemical activity of iron (hydr)oxides/Ox systems with varying structural properties. Herein, the photochemical behaviors of Ox on goethite (Gt) surface from the view of structural dependent activity, containment degradation, and ROS generation were explored in detail. Results confirmed that bidentate mononuclear was formed on Gt surface after complexing Ox. Combined with density functional theory calculation and pH time evolution during aniline degradation, the photochemical activity of the Gt/Ox system fell in between that of ferrihydrite/Ox and hematite/Ox systems. After irradiating 120 min visible light, 96.5% aniline was degraded by 1.0 mM Ox and 0.2 g/L Gt. The amount of •OH in vis/Gt/Ox system could be up to 309.3 μM and its generation was closely associated with Fe(II) while slightly affected by the generated H 2 O 2 . Moreover, as revealed by high-performance liquid chromatography with mass spectrometric and Ecological Structure Activity Relationships software, the toxicity of the intermediates of aniline degradation in the vis/Gt/Ox system towards fish and green algae increased first but then declined accompanied by the generation of non-toxic ring-opening products at the end of reaction. According to the findings in the presented study, it could be concluded that vis/Gt/Ox is a promising approach to wiping out aniline wastewater.
研究领域:
环境科学
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化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL RESEARCH
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2021
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IF 6.498
Li Li,Ruoning Guo,Sai Zhang,Yiming Yuan
In recent decades, sodium percarbonate (SPC) has been widely applied as a solid replacement for H 2 O 2 in advanced oxidation process (AOPs). In this study, ultraviolet (UV) light was utilized for SPC activation to investigate the aniline degradation performance. The effects of SPC dosages and UV irradiation on aniline degradation were elaborated. The removal efficiency was significantly improved by increasing either the SPC dosage or UV irradiation intensity. Moreover, scavenging experiments showed that •OH, CO 3 •− , and O 2 •− were the predominant reactive species for aniline degradation. Meanwhile, the variation in the amount of •OH in the UV/SPC system was monitored, which revealed the dominant role of •OH. As a result, the mechanism of aniline degradation by the UV/SPC system was demonstrated based on confirmed free radicals. Furthermore, aniline degradation by the UV/H 2 O 2 and UV/H 2 O 2 /Na 2 CO 3 system were compared with the UV/SPC system, and an enhancement by the addition of Fe(II) in the UV/SPC system was verified. Aniline degradation was not significantly affected by the initial pH or the presence of Cl − , SO 4 2− while NO 3 − , HCO 3 − and humid acid (HA) suppressed the reaction. In general, the UV/SPC system is a novel, green, and promising technology for aniline removal from aqueous solutions.
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
CHEMOSPHERE
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2019
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IF 5.108
Bin Ou,Jixiao Wang,Ying Wu,Song Zhao,Zhi Wang
The graphite felt (GF) was modified through the concentrated sulfuric acid , potassium permanganate and ammonia activation with the aim of improving the specific surface area, hydrophilicity and the electrocatalytic activity for the electrogeneration of hydrogen peroxide and its application in the electro-Fenton (EF). The modified graphite felt (M-GF) was characterized by contact angle, scanning electron microscope , X-ray photoelectron spectroscopy, Raman spectrum , cyclic voltammetry and electrochemical impedance spectroscopy. The surface physic-chemical characteristics and morphology of the M-GF were considerably changed after the modification. The current efficiency for H 2 O 2 generation was explored at an optimized current density of 10 mA cm −2 and the value of H 2 O 2 generation for the M-GF was 478.6 mg L −1 , while the GF was 276.5 mg L −1 after 360 min of electrolysis. Finally, the M-GF was used for the mineralization of aniline (100 mg L −1 ), reaching a mineralization percentage of 97% with EF process. The M-GF demonstrated good stability as the aniline mineralization percentage was above 90% after 10 cycles’ degradation, indicating that the M-GF is a promising cathode material for improving the degradation and mineralization of others organic pollutants by the EF process.
研究领域:
环境科学
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材料科学
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
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2018
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IF 4.427
Yao Wu,Jing Guo,Yijie Han,Junyi Zhu,Lixiang Zhou,Yeqing Lan
This study investigated the degradation of aniline by persulfate (PS) activated with rice straw biochar (RSBC). The results demonstrate that aniline could be rapidly decomposed by a combination of PS and RSBC. The degradation efficiency of aniline was up to 94.1% within 80 min, and meanwhile 52% of the total organic carbon was removed. In the initial pH range of 3–9, aniline could be efficiently removed. Reactive species resulting in the rapid degradation of aniline were investigated via radical and hole quenching experiments with various scavengers (e.g., methanol, tert -butyl alcohol and EDTA) and electron paramagnetic resonance technique. Based on the analysis and observation made here, it is speculated that the predominant reactive species responsible for the degradation of aniline may be holes instead of SO 4 − and OH radicals. It is concluded that RSBC could be used as an effective catalyst to activate PS for the degradation of aniline.
研究领域:
环境科学
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化学工程
✓ 已验证
DOI
PubMed
高影响因子
CHEMOSPHERE
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2018
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IF 4.427
Li Li,Jun Huang,Xuebin Hu,Sai Zhang,Qin Dai,Hongxiang Chai,Li Gu
Sodium percarbonate (SPC)-based advanced oxidation process has been applied to the wastewater treatment in recent years. In the present study, a novel catalyst utilization of vanadium(V) was investigated for the activation of SPC for aniline degradation. The mechanism of SPC activation by V(IV) was demonstrated, and the major free radicals were identified through scavenging tests and electron paramagnetic resonance (EPR) analysis. The performance of aniline degradation was evaluated in the V(IV)/H 2 O 2 and V(IV)/H 2 O 2 /Na 2 CO 3 systems and compared with that of the V(IV)/SPC system. The influences of initial pH and effects of inorganic anions were also studied. The results show that aniline could be decomposed efficiently by SPC activated with V(IV) and the degradation efficiency increased with the increase in V(IV) and SPC dosage. O 2 − , CO 3 − , and OH were found to participate in aniline degradation, and O 2 − and CO 3 − were confirmed to be the predominant species. The decomposition of aniline was enhanced when equal amount of H 2 O 2 was utilized instead of SPC under acidic condition while a comparative behavior was achieved in the V(IV)/H 2 O 2 /Na 2 CO 3 system. Furthermore, aniline degradation was not impacted significantly by the initial pH and addition of Cl − , SO 4 2− and NO 3 − , while HCO 3 − led to a betterment of aniline removal. These results indicate that the V(IV)/SPC system is an effective and promising approach for the removal of aniline from water for its feasibility and stability, which achieves eliminating contaminants by another waste.
研究领域:
环境科学
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化学工程
✓ 已验证
DOI
PubMed
高影响因子
CATALYSIS TODAY
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2018
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IF 4.667
Imtyaz Hussain,Yongqing Zhang,Mingyu Li,Shaobin Huang,Waseem Hayat,Liangming He,Xiaodong Du,Guoqiang Liu,Meimei Du
In this study, magnetic BiFeO 3 nanoparticles (BFO MNPs) were successfully synthesized by simple sole-gel method. The BFO MNPs catalyst was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), x-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FT-IR) techniques. The prepared catalyst was used to activate persulfate (PS) to generate sulfate radicals (SO4 − ) for the enhanced degradation of aniline from aqueous solution. It was found that BFO MNPs showed high catalytic activity toward PS decomposition for the degradation of aniline. The degradation efficiency of aniline (0.5 mM) was 100% within 120 min using initial dosage of 0.5 g/L BFO MNPs and concentration of 5 mM persulfate. Even at neutral pH (7.0), aniline was efficiently degraded in BFO MNPs /PS system. The effects of reaction parameters such as initial pH, PS concentration and dosage of BFO MNPs were investigated. The radical scavenging and electron paramagnetic resonance (EPR) results showed that sulfate radicals (SO4 − ) and hydroxyl radicals ( OH) were generated by the activation of PS with BFO MNPs for the degradation of aniline. The stability of catalyst was tested by means of successive reuse cycles. The results revealed that BiFeO 3 catalyst exhibited high reusability and stability in degrading aniline through PS activation .
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
CHEMICAL ENGINEERING JOURNAL
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2021
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IF 13.273
Xi Zheng,Tianyuan Xu,Xueyan Kang,Yaowen Xing,Yijun Cao,Xiahui Gui
Coke powder (CP), the by-product of coal carbonization, its activity of persulfate (PS) activation was systematically investigated. Structural dependent organic pollutant degradation performances and the related mechanisms were discussed in detail. The structural characteristics of CP were studied using X-ray diffraction, Raman, Fourier transform infrared spectra, X-ray photoelectron spectra, and electron paramagnetic resonance (EPR) etc. Characterization results indicate that CP contains ∼ 78% carbon and presents highly disordered amorphous structures with abundant oxygenated functional groups (OFGs) and persistent free radicals (PRFs). The catalytic application reveals that CP held excellent activity for PS activation across a wide pH range from 3 − 11. In the presence of 0.5 g/L CP, 0.25 mM PS and 0.021 mM aniline (pH 7 ± 0.2), >99% aniline was degraded within 40 min. Under the interference of inorganic anions (Cl − , HCO 3 − and SO 4 2− ), 98% aniline degradation efficiency still could be achieved. Meanwhile, quenching tests and EPR demonstrated that the superoxide anion radical (O 2 − ) was responsible for aniline degradation in CP/PS system, and its generation was independent of dissolved oxygen. The outstanding performance of aniline degradation and ROS generation were attributed to the existence of PRFs, sp 2 -hybridized carbon, OFGs and defects on CP inducing O–O bonding homolytic cleavage of PS into sulfate radicals. Besides, the OFGs including C–OH and –COOH as electron donors facilitated PS decomposition to generate O 2 − . The findings imply that CP is an excellent PS activator, and clarify the development of remediation materials by using by-products of coking process for wastewater treatment.
研究领域:
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
CHEMOSPHERE
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2023
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IF 8.8
Qianting Xu,Fengping Zhou,Qingxin Yu,Ye Xiao,Xinyi Jiang,Weihua Zhang,Rongliang Qiu
In the Pearl River Delta of China, many sites are likely contaminated with aniline in the soil and arsenic (As) in the groundwater because of a high As background level and the prevailing printing and dyeing industry. This study is to explore the remediation performance of thermally activated persulfate oxidation for the sites with these two contaminants, aniline and As. The As influence on the aniline degradation and vice versa are also systematically investigated. When the molar ratio of aniline to persulfate is 1: 4.65, over 85% of aniline can be degraded at 40 °C in 24 h, and 100 μg L −1 As(III) in solution can be completely adsorbed by the soil. A higher pH favored the aniline degradation but disfavored the As(III) oxidation. Due to the strong buffer capacity of the soil, aniline in the soil could be more quickly degraded than those in the solution. The As(III), however, seem more easily oxidized in the absence of soil. The coexisting Fe 2+ can substantially improve As(III) oxidation and immobilization, although the dilute Fe 2+ solution may suppress the aniline degradation. The presence of aniline severely inhibited the As(III) oxidation and adsorption, likely due to the competition for the generated free radicals and the adsorption sites on the soils. In contrast, the existing As(III) has a slight effect on aniline degradation. These findings are believed to provide the theoretical basis for the remediation of aniline-arsenic contaminated sites.
研究领域:
环境科学
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污染修复
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化学工程
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2015
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IF 4.321
Donghui Han,Jinquan Wan,Yongwen Ma,Yan Wang,Ying Li,Dongya Li,Zeyu Guan
Persulfate (PS) oxidation of aniline activated by several chelating agents (CAs) mediated ferrous iron (Fe(II)) was investigated. The effects of CAs structure, CA/Fe(II) ratios and pH on PS activation were studied in batch experiments ran for 120 min. Results showed that the accessible Fe(II) in the CA–Fe(II) complex was responsible for PS activation and appropriate Fe(II) accessibility was favored for more efficient utilization of Fe(II), which could improve the PS activation. Due to the steric hindrance, the number of chelating functional groups and the molecule size of CAs determined the Fe(II) accessibility. In addition, the Fe(II) accessibility was affected by the CA/Fe(II) ratio. When the ratio was 5/1, the Fe(II) accessibility followed the sequence: citric acid > oxalic acid > tartaric acid > (S,S)-ethylenediamine-N,N′-disuccinic acid (EDDS), but when the ratio was lower than 3/1, the accessibility followed the sequence: oxalic acid > tartaric acid > citric acid > EDDS. In tartaric acid processes, as high as 91.7% PS decomposition was obtained at initial pH 9. Although the acidification of solution might contribute to the high PS decomposition, Fe(II) buffering and Fe(II) recovery possibly played more important roles. Citric acid and tartaric acid were more effective in promoting PS activation and larger PS decomposition was observed in these processes under various initial pH. However, the intense competition for radicals by tartaric acid decreased the PS efficiency for aniline removal. The results of Electron Spin Resonance (ESR) and radicals quenching experiments indicated that both SO 4 − and OH contributed to the overall oxidation performance, but OH was the dominant oxidative species.
研究领域:
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
DYES AND PIGMENTS
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2023
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IF 4.5
Chunhong Gao,Jinjia Liu,Meilin Jia,Gala Sa,Aiju Xu
Photocatalytic technology has broad prospects in the degradation of organic pollutants due to its green, energy-saving and high-efficiency characteristics. In this study, TiO 2 and V–TiO 2 were prepared by hydrothermal method , and the catalysts were tested by experimental and theoretical calculations under a 400 W metal halide lamp degradation efficiency for aniline (30 mg/L). The synthetic photocatalysts were characterized by XRD , HRTEM , FT-IR, XPS , UV–Vis DRS , PL , EIS , and photocurrent , the results showed that the edges of the V-doped TiO 2 absorption band were redshifted, the band gap value were reduced, the photocatalytic activity were improved, and the PL showed e − /h + had the lowest composite rate for 1.5 mol%V–TiO 2 and broadens the optical response range. 1.5 mol% V was the optimal value for photodegrading aniline, and moderate V modification can significantly inhibit the complexation of e − /h + pairs. Finally, stability measurements performed over 5 cycles show that 1.5 mol%V–TiO 2 has excellent stability. The calculation results show that the optical band gap of V–TiO 2 were significantly reduced, the photocatalytic performance of V–TiO 2 were greatly enhanced.
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
CHEMOSPHERE
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2020
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IF 5.778
Zhiming Yan,Yong Gu,Xing Wang,Yueli Hu,Xia Li
Wastewater contains a large number of anions and organics which can scavenge reactive radicals and limit the application of sulfate radical-based advanced oxidation processes (SR-AOPs) in practical engineering. Here, we studied the removal rate and mechanism of aniline by SR-AOPs in different influencing factors, such as sodium persulfate dosage, ferrous ions dosage, solution pH, Cl - , HCO 3 - , NO 3 - , and other organic matter. By recognizing and analyzing free radicals, we concluded that SO 4 •- plays a major role in aniline degradation. The aniline removal rate increased with the initial concentrations of persulfate and ferrous ions, but aniline degradation was inhibited by excessive dosage. The aniline removal rate by ferrous-ions-catalyzed persulfate was higher under acidic conditions and could be improved under alkaline conditions if no ferrous ions were added. The addition of bicarbonate ions inhibited aniline removal, and the addition of nitrate ions barely caused the effect. While the addition of chloride ions promoted aniline degradation, which was confirmed that HClO generated from the reacting of Cl - and persulfate played a key role. However, TOC indicated that aniline was not completely mineralized in the process. Further analysis of the products from GC-MS demonstrated that chloride-ion additions produced some harmful halogenated by-products. Our results can act as a basis for developing processes for the aniline degradation in wastewater.
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
危险品化学品经营许可证（带存储）