CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Chen-Xuan Li,Chang-Bin Chen,Yun-Jie Wang,Xian-Zhong Fu,Shuo Cui,Jia-Yuan Lu,Jie Li,Hou-Qi Liu,Wen-Wei Li,Tai-Chu Lau
The formation of halogenated disinfection byproducts (DBPs) during organic pollutants degradation in advanced oxidation processes (AOPs) has raised growing concerns globally. However, the detailed roles of chlorine ions (Cl − ) in pollutant degradation by peroxymonosulfate (PMS) alone remain controversial so far. Here, we shed light on the PMS-Cl − -phenol interactions and revealed a previously overlooked pH-dependent phenol transformation pathway. At acidic pH, Cl − significantly accelerated the phenol removal. The Cl − -PMS reaction resulted in abundant reactive chlorine species, which attacked phenol to form 4-chlorophenol and 2, 4-dichlorophenol as the main transformation products. In contrast, the impact of Cl − became negligible at alkaline pH. Raising the pH severely suppressed the phenol chlorination and significantly stimulated generation of singlet oxygen ( 1 O 2 ) for degradation of phenol and the minor formed chlorophenols. The 1 O 2 was resulted from a combined effect of PMS self-decomposition and PMS-benzoquinone interaction at alkaline pH. Our results imply a previously-underestimated impact of Cl − on phenolic compounds degradation in PMS-based AOPs and underscore a potential risk of chlorinated DBPs formation under environmental conditions.
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
ACS ES&T Water
·
2022
·
IF 0
Nan Chen,Juzhuan Ruan,Sen Lu,Zhen Sun,Guan Zhang
Indirect electrocatalytic (EC) oxidation of ammonia into harmless N2 based on in situ generated reactive chlorine species from chlorinated aqueous streams has been considered as an effective technique for ammonia abatement from water/wastewater. However, the precise oxidation mechanism and contribution of reactive species to the ammonia oxidation are still under debate and deserved to be specifically investigated. In order to enhance mass transfer efficiency, this work systematically investigated and optimized a three-dimensional EC (3D-EC) system, which exhibits about two times higher ammonia oxidation rate compared to a two-dimensional EC system. The polarization characters of particle electrodes have been analyzed to correlate with the enhanced generation of ·OH and ClO· radicals under biased conditions, and the role of each oxidative species was specifically quantified. In the enlarged scale study, water flow-by mode was tested with varying experimental parameters including flow rate, hydraulic residence time, and secondary oxidation. Furthermore, the performance of the 3D-EC system for the treatment of six types of practical wastewater with different levels of ammonia and organics was evaluated. This study provides mechanistic insight on the indirect 3D-EC oxidation of ammonia and its potential application on ammonia wastewater treatment.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Zhaofen Xu,Lingfang Tang,Yuanyi Zhou,Gang Lu,Haojie Dong,Mingshan Zhu
Utilizing the immanent salt (Cl – ) in wastewater to generate reactive chlorine species (RCS) satisfies the future needs for sustainable, on-demand, and decentralized ammonia nitrogen (NH 4 + -N) removal. The microstructural evolution of bismuth oxychloride (BiOCl) photocatalyst under irradiation benefits for overcoming the competition between Cl – and H 2 O oxidation and achieving high N 2 selectivity. Herein, internal electric field (IEF) engineering by carbon doping is applied to promote photocatalytic RCS generation rate over BiOCl. The carbon dopant not only enhances the IEF intensity of BiOCl by a factor of 2.1 times for carrier dynamics promotion, but also improves Cl – oxidation against H 2 O oxidation. An RCS production rate of 0.23 mg/L min −1 is realized over carbon-doped BiOCl (C-BiOCl) through the accelerated interaction between lattice and environmental Cl – , which is twice that of the undoped BiOCl (0.11 mg/L min −1 ). The relation between IEF intensity and RCS generation rate over C-BiOCl manifests a correlation coefficient of 0.96. Effective NH 4 + -N degradation with N 2 selectivity of >99% is validated. The system is competent in dealing with saline NH 4 + -N wastewater with a wide range of NH 4 + -N (20∼200 mg N/L) and NaCl (6∼10 g/L) concentrations. In the treatment of realistic landfill leachate (884 mg N/L NH 4 + -N), C-BiOCl displays a photocatalytic NH 4 + -N removal efficiency of up to 95.6% while maintaining the NO 2 − -N (∼2 mg N/L) and NO 3 − -N (∼40 mg N/L) levels. This system provided an interesting and innovative idea for wastewater self-purification.
研究领域:
环境科学
·
废水处理
✓ 已验证
产品关联
DOI
高影响因子
Journal of Water Process Engineering
·
2025
·
IF 6.7
Chengzhi Zhou,Zhen Wang,Haoran Wang,Yanlong Sun,Lei Yang,Hangyang Feng,Liguo Shen,Xia Tian,Junfeng Niu
In the present work, the electrochemical degradation of artificial sweetener alitame was performed by using two-dimensional plate anode and three-dimensional porous membrane anode. The results show that the alitame degradation rate increased about 10 times and energy consumption reduced 10 times, when the plate anode was replaced by porous membrane anode. The degradation rate constant of alitame was 0.305 min −1 and the energy consumption was 0.27 Wh L −1 using membrane anode at current density of 2 mA cm −2 . The presence of NO 3 − and HCO 3 − inhibited the alitame degradation, while Cl − improved the alitame removal significantly. The promotion effect was mainly ascribed to free chlorine specie in high chlorine content, and the effect in low chlorine content was attributed to ·OH, chlorine radical and free chlorine specie together. Twenty-six degradation products including three chlorinated intermediates were identified in the presence of chloridion. The degradation process mainly included hydroxylation, dehydrogenation, sulfur-replaced reaction, dehydration condensation and chlorinated reaction. Toxicity analysis results show that potential risks in developmental toxicity and mutagenicity should be not ignored when chloridion exists. These results demonstrate that electrocatalysis with three-dimensional membrane anode exhibits high efficiency in removing artificial sweeteners especially in a chlorine environment.
研究领域:
环境科学
·
电化学
·
毒理学
✓ 已验证
产品关联
DOI
高影响因子
WATER RESEARCH
·
2023
·
IF 12.8
Jiakai Qiu,Jing Wang,Mingzhu Ren,Xin Yang,Jianbo Zhang,Xiaolong Zhang,Hongbin Cao,Yongbing Xie
Chloride ion (Cl − ) is one of the most common anions in wastewater and saline wastewater, but its elusive effects on organics degradation are not clear yet in many cases. In this paper, the effect of Cl − on organic compounds degradation is intensively studied in catalytic ozonation of different water matrix. It was found that the effect of Cl − is almost completely reflected by transforming ·OH to reactive chlorine species (RCS), which is simultaneously competitive with organics degradation. The competition between organics and Cl − for ·OH directly determines the ratio of their consumption rate of ·OH, which depends on their concentration and reactivity with ·OH. Especially, the concentration of organics and solution pH may change greatly during organics degradation process, which will correspondingly influence the transformation rate of ·OH to RCS. Therefore, the effect of Cl − on organics degradation is not immutable, and may dynamically change. As the reaction product between Cl − and ·OH, RCS was also expected to affect the degradation of organics. But we found that Cl· had no significant contribution to the degradation of organics in catalytic ozonation, which may due to its reaction with ozone. Catalytic ozonation of a series of benzoic acid (BA) with different substituents in chloride contained wastewater was also investigated, and the results showed that the electron-donating substituents can weaken the inhibition of Cl − on BAs degradation, because they increase the reactivity of organics with ·OH, O 3 and RCS.
研究领域:
环境科学
·
废水处理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2023
·
IF 13.6
Wenzhe Liu,Baiyang Chen,Yang Yang,Boqiang Li,Huimei Pan,Wang Luo
Excessive ammonia (NH 4 + ) discharge can lead to algal blooms and disrupt water sustainability, so its control is imperative. Although microbiology-triggered anammox process is promising, its application is limited due to time-consuming cultivation of specific microorganisms and need for skilled operation. To bypass these barriers, this study proposed and verified a photo-induced anammox technology that removes NH 4 + and total nitrogen (TN) from water by ultraviolet (UV)/vacuum UV (VUV)/chlorine under anoxic conditions . Under the Cl/N mass ratio of 5:1, the anoxic VUV/UV/chlorine process achieved 66.8% removal of 10 mg-N/L NH 4 + within 10 min along with 57.8% reduction in TN. Besides the evidence from TN loss, this study confirmed nitrogen gas (N 2 ) as the primary degradation product at low dissolved oxygen (DO) concentration of 2.0 mg/L. The selective conversion of NH 4 + into N 2 was mainly attributed to reactive nitrogen species (RNS, 42.5%) and reactive chlorine species (RCS, 57.5%). The TN removal efficiency was insensitive to certain variations of pH (7.0–9.0), NH 4 + concentration (1–30 mg-N/L), chloride (50–125 mg/L), and sulfate (25–100 mg/L), but sensitive to DO and bicarbonate (25–100 mg/L). Given its robustness and high efficiency, the anoxic VUV/UV/chlorine technology may serve as a potentially promising alternative for NH 4 + and TN alleviation in wastewater.
研究领域:
环境科学
·
微生物学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2024
·
IF 12.2
Xiaoyang Li,Han Zhang,Jiahang Liu,Yingying Chu,Mengying Qian,Zhichao Yang,Ming Hua,Weiming Zhang
Chloride ion (Cl − ) is ubiquitous in diverse water bodies, yet poses a longstanding challenge in water pollution control by hindering the efficiency of pollutant degradation. Herein, we proposed a novel concept involving the direct utilization of endogenous Cl − ions in water for rapid water purification within a non-redox zirconium oxide (ZrO 2 )-activated peroxymonosulfate (PMS) system. In this process, PMS was complexed on the ZrO 2 surface through inner-sphere coordination, and effectively activated by the partial electron cloud deviation from Zr(IV) sites to PMS, thereby forming a metastable surface complex with an elevated redox potential. Afterwards, the coexistence of Cl − could trigger the transformation of the reactive complex into free chlorine species, thus leading to a 255.0-fold enhancement in the elimination rate of micropollutants compared with the ZrO 2 /PMS system. Quantitative structure-activity relationship analysis revealed that the ZrO 2 /PMS/Cl − system displayed strong target-dependence towards electron-rich compounds, showcasing a faster oxidation rate for pollutants with higher E HOMO energy levels. Significantly, the novel system performed robust resistance to complex water matrices, achieved low oxidant consumption for pollutant removal, and demonstrated adaptation across a broad range of Cl − concentrations (1.0–100.0 mM). Overall, our findings provide new mechanistic insights into the influence of Cl − ions on PMS activation, which refresh the understanding of the role of Cl − ions on pollutant degradation, and help to guide the treatment design for chloride-containing wastewater.
研究领域:
环境科学
·
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
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Tangrui Hou,Yujun Zhou,Yang Zhao,Jiansheng Li,Lixiang Zhou
Chlorine-mediated electrochemical advanced oxidation (EAO-Cl) process, which converted Cl - into highly oxidizing active chlorine species under electricity, exhibits exceptional performance in wastewater pollutants removal. In this study, degradation of p -Nitrophenol (PNP) through EAO-Cl was investigated with RuO 2 /Ti foam as anode and Ti foam as cathode. Under high salinity (342 mM NaCl) condition, 95.4 % of PNP with initial concentration of 20 mg/L was removed within 120 min. The reaction kinetics constant was 0.0265 min −1 , which increased nearly 14 times compared to that of in low salinity (25 mM NaCl). ESR and quenching experiments were employed to identify the in-situ generated reactive chlorine species and evaluate their relative contributions to the degradation process. It was found that chlorine radicals (·Cl) was the dominant oxidants and contributed 60.0 % to PNP degradation. The reaction mechanisms and PNP degradation pathways mediated by chlorine species were further elucidated. Long-term continuous reactor operation revealed that PNP was near-completely removed in single-pass mode with energy consumption of 5.22 kWh/m 3 . This study proposed a novel “waste to treat waste” approach for contaminant removal in high-salinity wastewater by in situ conversion of unwanted chloride ions into useful reactive chlorine species, simultaneously enabling pollutant degradation and resource utilization from inherent wastewater salinity.
研究领域:
环境工程
·
电化学
·
水处理技术
·
化学工程
·
污染控制
·
高级氧化工艺
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2018
·
IF 4.427
Xinran Zhang,Jun He,Shuqi Xiao,Xin Yang
Microcystin-LR (MC-LR), a toxin produced by cyanobacteria, is very toxic and poses a threat to public health when entering water treatment works. In this study, UV/chlorine process, as an advanced oxidation process (AOP), has been demonstrated for effective elimination of MC-LR levels and associated toxicity. At a chlorine dose of 3.0 mg L −1 and UV fluence of 125 mJ cm −2 , MC-LR (initial concentration 1.0 μM) was reduced by 92.5%, which was much higher than 20.3% removal under UV irradiation alone and 65.1% removal during dark chlorination. Enhanced degradation was attributed by hydroxyl radicals (HO ) and reactive chlorine species (RCS), mainly Cl 2 - and ClO . Increasing chlorine doses or lowering pH favored MC-LR removal. Increased bicarbonate and natural organic matter concentrations inhibited MC-LR removal, but bromide ions enhanced MC-LR removal instead. MC-LR elimination rates in natural waters were roughly two times smaller than those in ultrapure water. The reactive radicals promoted hydroxylation of both diene of Adda moiety and double bond of Mdha moiety in MC-LR. UV exposure enhanced the dechlorination of chloro-MC-LR via the cleavage of C Cl bond. The toxicity was evaluated by a protein phosphatase (PP2A) inhibition assay. At a chlorine dose of 3.0 mg L −1 and UV fluence of 125 mJ cm −2 , the toxicity of the treated water was reduced by 75.0%, which was also higher than 25.7% and 46.7% removal under UV irradiation alone and during dark chlorination, respectively. These results highlight UV/chlorine is an efficient AOP for MC-LR degradation and detoxification.
研究领域:
环境科学
·
水处理工程
·
毒理学
✓ 已验证
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Haina Bai,Jian Zhang,Shipeng Li,Muchen Lu,Jia Li,Ruoyi Li
In this study successfully prepared AG@MXene/CC composite electrodes by employing a thermosolvation-ultrasonication technique combined with an impregnation method. This approach uniformly dispersed MXene, known for its high electrochemical properties, onto the surface of carbon cloth (CC) through biomass-derived AG hydrogels featuring a three-dimensional network structure. The hydrogen bonding and van der Waals forces between AG and MXene were harnessed to enhance material interactions, thereby improving electron transfer efficiency and electrocatalytic activity. Experimental results demonstrated that the composite electrode could achieve up to 96.16 % degradation rate of tigecycline (TGC) within 30 min under optimal conditions. Furthermore, this study delved into the reaction mechanism of the electrocatalytic system, clarifying the key roles of H* and H 2 O 2 generated at the cathode, as well as ·OH and active chlorine species on the anode's surface during the TGC degradation process. A synergistic catalytic mechanism for the cathode and anode was proposed. The intermediates that may be formed during TGC degradation were analyzed and their toxicity was evaluated, confirming the high biosafety of the treated wastewater. This work not only offers new insights for designing efficient and stable electrocatalysts but also broadens the application scope of the green material AG in the electrocatalytic degradation of antibiotics.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2017
·Vol. 25
·期 1
·672-682
·
IF 2.741
Shi Xue-Ting,Liu Yong-Ze,Tang Yu-Qing,Feng Li,Zhang Li-Qiu
UV/chlorine, as a novel disinfection method, has attracted great interest due to its effective removal for pathogenic microorganism and degradation of trace organic contaminants existed in water environment. This paper investigated the degradation kinetics and pathways of Bezafibrate (BZF), a typical antilipemic drug, during UV/chlorine process. The results showed that 92.3% of BZF was degraded after 20 min in UV/chlorine process. This indicated HO• and reactive chlorine species (RCSs) formed in UV/chlorine played the dominant role in degrading BZF. Observed rate constants of BZF degradation ( k
obs,BZF ) in UV/chlorine process increased linearly in a wide chlorine dosage from 0.1 to 1.0 mM, which implied that ClO• generated from the reactions of chlorine with HO• and Cl• could react with BZF rapidly. The steady-state kinetic modeling result proved this deduction and the rate constant of ClO• with BZF was fitted to be 5.0 × 10 8 M −1 s −1 . k
obs,BZF was affected by Cl − and HA. The total contribution of RCSs (including Cl•, Cl 2 • − , and ClO•) to the degradation of BZF was determined to be ~ 80%, which is much higher than that of HO•. Thirteen degradation products of BZF were identified by LC-MS/MS. Initial degradation products were arisen from hydroxylation, chlorine substitution and cyclization by HO• and RCSs, and then further oxidized to generate acylamino cleavage and demethylation products.
研究领域:
环境科学
·
水处理工程
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）