ACS Sustainable Chemistry & Engineering
·
2016
·
IF 5.267
Yuan-Ying Wang,Xiang-Rong Jing,Ling-Li Li,Wu-Jun Liu,Zhong-Hua Tong,Hong Jiang
Biochar is a solid material obtained from thermochemical conversion of biomass in an oxygen-limited environment. It is widely used as a soil remediator and carbon sequestrator. However, its biotoxicity to the ecosystem remains unclear. In this study, we assess the toxic effects of three fast pyrolytic biochar extract solutions (rice husk, saw dust, Acorus calamus) on a miocroorganism (Pseudomonas aeruginosa), a plant (Triticum spp.), and an animal (Caenorhabditis elegans). Systematic toxicity tests indicate that the biotoxicity of biochars varies with their biomass sources. Biochars derived from rice husk and sawdust have negligible toxic effects on all the tested organisms, suggesting that biochars obtained from agricultural waste are safe for soil application. By contrast, biochar derived from Acorus calamus shows significant toxicity on all tested organisms at relative high dosage, indicating that risk assessment is necessary before its environmental use. Furthermore, this study found that use of the UV254 value is more practical than the SUV254 value for evaluation of biochar biotoxicity. Finally, gel permeation chromatography (GPC) suggests that certain small aromatic molecules may be responsible for the toxicity of biochar derived from Acorus calamus.
研究领域:
环境科学
·
毒理学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
·
2023
·
IF 8.7
Miao Yu,Rui Gao,Xinyuan Lv,Minghao Sui,Tian Li
Disinfection is widely applied in water and wastewater treatment to inactivate viruses. However, the inactivation mechanism associated with viral structural alteration during disinfection is still not clear. In this work, inactivation of bacteriophage phiX174 by ultraviolet radiation (UV 254 ) and free chlorine (FC), two most commonly used disinfection processes , was studied at the molecular level to investigate the relationship between phiX174 genome impairment and virus inactivation, and the correlation between protein impairment and function loss. Double-layer agar technique, quantitative real-time polymerase chain reaction (qPCR), real-time reverse transcription-polymerase chain reaction (RT-qPCR), and liquid chromatography-tandem mass spectrometry techniques (LC-MS/MS), together with structure impairment and function experiments were implemented to quantitatively analyze the inactivation and damage to genome and proteins of phiX174. Results showed that UV 254 and FC could effectively inactivate phiX174 at the practical doses (UV 254 dose of 30 mJ/cm 2 , and FC of 1–3 mg/L) used in water treatment plants , accompanied with the damage to viral genome and proteins. Specifically, a UV 254 irradiation dose of 9.6 mJ/cm 2 , and FC at an initial concentration of 1 mg/L at 4 min could lead to a 4-log 10 inactivation. Nevertheless, the combination of these two methods at selected doses played no significant synergistic disinfection effect. During UV 254 disinfection, the proportion of phiX174 with damaged genome was similar with that of the inactivated phiX174. In addition, UV 254 and FC could disrupt proteins of phiX174 such as H protein, thereby hindering the physiological function associated with these proteins. With these findings, it is suggested that UV 254 and FC disinfection could hinder the injection of the viral genome into host cells, thus resulting in the inactivation of phiX174. This work provides a comprehensive study of the inactivation mechanism of phiX174, which can enhance the applicability of UV 254 and FC in water treatment plants, and facilitate the design and optimization of disinfection technologies for virus control in drinking water and wastewater worldwide to ensure the biosafety .
研究领域:
环境科学
·
微生物学
·
水处理
·
病毒学
✓ 已验证
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2018
·
IF 3.927
Yinan Bu,Liwei Wang,Baiyang Chen,Ruilan Niu,Yi Chen
This study investigated a range of typical water components and parameters, including pH, carbonate, bicarbonate, halides , nitrate, dissolved organic matter (DOM), free chlorine, and initial concentration, on the photodegradation kinetics of seven different haloacetic acids (HAAs) with different halogen substitutions. The results show that the photolysis rates can generally be enhanced by additions of free chlorine and iodide yet decelerated by increases of DOM and bromide. In contrast, pH and feeding HAA concentration did not affect the photodegradation of HAAs significantly over pH ranges from 6 to 11 or doses from 0.05 to 50 mg/L. One exception existed that hydroxide, bicarbonate, and carbonate apparently inhibited the photolysis kinetics of monochloroacetic acid, suggesting that indirect photolysis via hydroxyl radical was partially responsible for this compound. As for the combined influences of water matrix, the photolysis rates of HAAs dosed into tap, lake, and ocean waters were lower than those dosed into ultrapure water by on average 21–38%, indicating that most components in these real waters tended to suppress the photolysis. The study therefore demonstrates the complexity of DBP removal using a UV system, and such results may help assessment of the real potential of UV photolysis for HAA control in water.
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
JOURNAL OF HAZARDOUS MATERIALS
·
2025
·
IF 11.3
Wei Wang,Qirui Wu,Hanzhi Wang,Mingxiang Qv,Dian Dai,Xiaoman He,Ivan P. Pozdnyakov,Li-Zhi Huang,Liandong Zhu
This study investigated the UV 254 irradiation degradation of chloroacetic acids (CAAs), specifically monochloroacetic acid (MCAA), dichloroacetic acid (DCAA), and trichloroacetic acid (TCAA), and evaluated the ecological impact of their degradation products on Chlorella sorokiniana (CS). The degradation followed first-order kinetics, with dechlorination efficiencies of 91.2% for MCAA, 92.9% for DCAA, and 92.4% for TCAA. TCAA was degraded fastest due to its higher chlorine content. Initial pH (3–10) had minimal influence, whereas lower concentrations (0.25 mM) led to slower degradation. Hydroxyl radicals (•OH) were identified as the dominant reactive species via electron paramagnetic resonance analysis. Dechlorination generated Cl⁻ and HCl, resulting in acidification and increased toxicity. Total organic carbon (TOC) analysis indicated nearly complete mineralization. Untreated CAAs significantly inhibited microalgal growth and photosynthesis, while post-degradation pH adjustment (to pH > 4) mitigated toxicity and enabled microalgal assimilation, with CS culture pH further increasing to 9–10, thereby facilitating self-buffered bioremediation. These findings confirm the effectiveness of UV 254 degradation on CAAs and provide valuable guidance for ecological safety in aquatic ecosystem management.
研究领域:
环境科学
·
水处理
·
光催化
·
生态毒理学
·
藻类生物技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMOSPHERE
·
2022
·
IF 8.943
Boyin Yan,Songxue Wang,Zhiquan Liu,Da Wang,Wenxin Shi,Fuyi Cui
In this work, the UV 254 /H 2 O 2 process was utilized to remove β-N-methylamino- l -alanine (BMAA), a kind of cyanobacteria neurotoxin, and the influence of reaction parameters and environmental factors on the degradation of BMAA has been systematically investigated. The results showed that BMAA could be effectively removed in the UV 254 /H 2 O 2 system compared to UV or H 2 O 2 alone and OH was confirmed as the main ROS to degrade BMAA. The degradation rate of BMAA increased first and then decreased with the increase of pH and the maximum k obs was 0.1545 min −1 obtained at pH 9. The removal of BMAA in the UV 254 /H 2 O 2 system was inhibited in actual water, while the degradation rate of BMAA in actual water could still exceed 90% by appropriately extending the reaction time. The decrease in the degradation efficiency of BMAA in actual water was primarily due to the ultraviolet light absorption and competition effects of NOM, and anions (Cl − and HCO 3 − ) would also inhibit the degradation of BMAA. Five by-products ([M − H] - = 118, 103, 88, 87 and 59) were identified in this study and the degradation pathways of BMAA were proposed. The production of by-products was attributed to the fracture of the C–N bond and hydroxylation reaction. This study is worthwhile to deepen the understanding of the degradation mechanism of BMAA in the UV 254 /H 2 O 2 system.
研究领域:
环境科学
·
毒理学
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2022
·
IF 14.224
Yihua Chen,Hang Ma,Jiaxin Zhu,Yurong Gu,Tongzhou Liu
UV/Fe 3+ -facilitated PFOA defluorination was often reported and recognized to proceed through a “ligand-to-metal charge transfer (LMCT)” mechanism in the literatures. Sufficient Fe 3+ supply is important for sustaining the LMCT reaction pathway. In this study, an interesting “excessive defluorination” was observed, even the continuous Fe 3+ supply was cut off, implying a parallel mechanism strengthening PFOA defluorination . Based the results of intermediate products detection, 19 F NMR analysis, and exploration of electron density alternation, transition energy evolution, and bonds characteristics, remarkable electron density perturbation in [PFOA-Fe] 2+ was revealed. This effect was triggered by the complexation between PFOA anion and Fe 3+ , diminishing electron shielding on the perfluorinated carbon chain. Hence, the dissociation energy of C–C bonds was reduced by maximally 53% (C4-C5). Once attacked by high-flux UV 254 photons, the perfluorinated carbon chain underwent scission , and subsequent defluorination was achieved via hydrolysis reactions. This parallel mechanism cooperated with the LMCT mechanism, leading to the observed “excessive defluorination.” The degree of UV/Fe 3+ -synergized PFOA defluorination depended on UV 254 photon flux and Fe 3+ dosage. High UV 254 intensity guaranteed fast defluorination kinetics. A [Fe 3+ ]/[PFOA] molar ratio near 1 showed the best UV/Fe 3+ synergic effect on PFOA defluorination.
研究领域:
环境科学
·
化学
✓ 已验证
DOI
PubMed
高影响因子
WATER RESEARCH
·
2024
·
IF 11.4
Yihua Chen,Jiaxin Zhu,Hang Ma,Yurong Gu,Tongzhou Liu
Perfluorooctane sulfonate (PFOS) is a persistent organic pollutant posing a risk in environmental persistence, bioaccumulation and biotoxicity. This study was to reach a comprehensive and deeper understanding of PFOS elimination in a UV 254 photolytic treatment with the co-presence of Fe 2+ and nitrilotriacetic acid trisodium salt (NTA). PFOS defluorination was noticeably enhanced in the UV/Fe 2+ -NTA treatment compared with UV/NTA, UV/Fe 2+ and our previously studied UV/Fe 3+ treatments. UV–vis, FTIR, and UPLC/MS-MS results indicated the formation of PFOS-Fe 2+ -NTA complex in PFOS, Fe 2+ and NTA mixture. The transition energy gap of PFOS-Fe 2+ -NTA decreased below the excitation energy supplied by UV 254 irradiation, corresponding with red shift appearing in UV–vis scanning spectrum. This favored intramolecular electron transfer from Fe 2+ -NTA to PFOS under UV 254 irradiation to form electron-accepting PFOS. Molecular electrostatic potential and atom charge distribution analyses suggested electron density rearrangement and perturbation in the perfluorinated carbon chain of electron-accepting PFOS, leading to the decrease in bond dissociation energies. Intermediate products detection suggested the parallel defluorination pathways of PFOS desulfonation, middle carbon chain scission and direct C-F cleavage. NTA exhibited crucial functions in the UV/Fe 2+ -NTA treatment by holding Fe 2+ /Fe 3+ in soluble form as a chelant and favoring water activation to generate hydrated electrons (e aq − ) under UV irradiation as a photosensitizer. Fe 2+ acting as the conduit for electron transfer and the bridge of PFOS anion and NTA was thought functioning best at 200 µM in this study. The degree of UV/Fe 2+ -NTA -synergized PFOS defluorination also depended on e aq − yield and UV 254 photon flux. The structure dependence on the electron transfer process of PFOS and PFOA was explored incorporating molecular structure descriptors. Because of possessing greater potential to acquire electrons or less likeliness to donate its electrons than PFOA, PFOS exhibited faster defluorination kinetics in the published “reduction treatments” than “oxidation” ones. Whereas, PFOA defluorination kinetics were at similar level in both “reduction” and “oxidation” treatments.
研究领域:
环境科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
International Journal of Minerals Metallurgy and Materials
·
2024
·Vol. 31
·期 3
·574-584
·
IF 5.6
Huo Xiangtao,Chai Rongxia,Gou Lizheng,Zhang Mei,Guo Min
The coagulation process is a widely applied technology in water and wastewater treatment. Novel composite polyferric magnesium–silicate–sulfate (PFMS) coagulants were synthesized using Na 2 SiO 3 ·9H 2 O, Fe 2 (SO 4 ) 3 , and MgSO 4 as raw materials in this paper. The effects of aging time, Fe:Si:Mg, and OH:M molar ratios (M represents the metal ions) on the coagulation performance of the as-prepared PFMS were systematically investigated to obtain optimum coagulants. The results showed that PFMS coagulant exhibited good coagulation properties in the treatment of simulated humic acid–kaolin surface water and reactive dye wastewater. When the molar ratio was controlled at Fe:Si:Mg = 2:2:1 and OH:M = 0.32, the obtained PFMS presented excellent stability and a high coagulation efficiency. The removal efficiency of ultraviolet UV 254 was 99.81%, and the residual turbidity of the surface water reached 0.56 NTU at a dosage of 30 mg·L −1 . After standing the coagulant for 120 d in the laboratory, the removal efficiency of UV 254 and residual turbidity of the surface water were 88.12% and 0.68 NTU, respectively, which accord with the surface water treatment requirements. In addition, the coagulation performance in the treatment of reactive dye wastewater was greatly improved by combining the advantages of magnesium and iron salts. Compared with polyferric silicate–sulfate (PFS) and polymagnesium silicate–sulfate (PMS), the PFMS coagulant played a better decolorization role within the pH range of 7–13.
研究领域:
环境工程
·
水处理技术
·
化学合成
·
废水管理
·
材料科学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Qingshui Fan,Xiaoxiang Cheng,Xuewu Zhu,Congwei Luo,Huixue Ren,Daoji Wu,Heng Liang
In this study, a heterogeneous carbon nanofiber supported Co 3 O 4 (Co 3 O 4 @CNF) catalyst was prepared, and peroxymonosulfate (PMS) oxidation activated by Co 3 O 4 @CNF integrated with ultrafiltration (UF) membranes was proposed for treating secondary wastewater. The micromorphology and chemical composition of Co 3 O 4 @CNF were characterized by various techniques, demonstrating the successful synthesis of Co 3 O 4 @CNF. The prepared catalyst exhibited superior catalytic performance for PMS, accompanied by the formation of various reactive oxygen species, including • OH, SO 4 •− , 1 O 2 and O 2 •− . The Co 3 O 4 @CNF/PMS system substantially enhanced the removal of effluent organic matter (EfOM), and the DOC and UV 254 values were decreased to 3.8 mg/L and 0.032 cm −1 , with removal rates of 46.5% and 58.4%, respectively. The reduction efficiency of various fluorescent components was also improved, while macromolecular and humic substances were significantly reduced, accompanied by the generation of some small molecular organics. For both polyether sulfone and ceramic membranes, the fouling caused by EfOM was effectively mitigated, with the irreversible fouling resistance reduced by 65.6% and 83.9%, individually. The main fouling mechanism was also changed by increasing the specific filtration volume for the formation of cake filtration. The effectiveness of Co 3 O 4 @CNF/PMS for fouling mitigation was verified through the characterization of the surface morphology and functional groups of the membranes. The results suggest that the process of PMS activated by Co 3 O 4 @CNF integrated with UF has an application potential for secondary wastewater treatment.
研究领域:
环境工程
·
水处理
·
催化
·
膜技术
✓ 已验证
产品关联
DOI
高影响因子
ACS ES&T Water
·
2024
·
IF 4.8
Jiawei Chen,Lin Du,Jian Liu,Lifeng Lin,Min Zhao,Lei Wang,Shaohua Chen,Jianzhi Huang
This study investigated innovative advanced oxidation processes (AOPs) combining far-UVC radiation at 222 nm with sodium percarbonate (SPC) to effectively remove methotrexate (MTX). UV222 significantly enhanced the direct photolysis and AOP degradation of MTX. •OH, CO3•–, and direct photolysis were primarily involved in the degradation, with their relative contribution being in the order •OH > CO3•– > direct photolysis. The fluence-normalized steady-state concentrations of both CO3•– and •OH in UV222/SPC were 7.76 and 4.05 times higher, respectively, than those in UV254/SPC. Transformation product analysis revealed distinct MTX degradation pathways and varied degradation rates of MTX substructures between the systems, with the order in UV254/SPC being 4-aminobenzamide (ABZ) > 2,4-diamino-6-(hydroxymethyl) pteridine (DHP) > l-glutamic acid (LG) and that in UV222/SPC being DHP > ABZ > LG, suggesting different reactivities of MTX moieties under each system. The presence of HCO3– and HA inhibited the MTX degradation, whereas NO3– promoted it, in the UV222/SPC system. In addition, UV222/SPC demonstrated a lower energy consumption compared to UV254/SPC, highlighting its potential for cost-effective wastewater treatment applications. This study offers new insights into the mechanisms of UV222/SPC systems and provides guidance for the development of technologies for the removal of emerging contaminants.
研究领域:
环境科学
·
化学工程
·
水处理
✓ 已验证
产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2023
·
IF 9.8
Weiwei Bi,Xin Zhang,Lei Wang,Yuzhe Ding,Shijun Zhu,Xiaoyan Ma,Qingsong Li,Xueyan Li,Jing Deng
This study systematically compared the degradation kinetics, conversion pathways, formation of disinfection by-products (DBPs), and changes in toxicity for sulfamethazine and carbamazepine in UV/nitrate system. Additionally, the study simulated the generation of DBPs in the post-chlorination process after the introduction of bromine ions (Br − ). The contributions of UV irradiation, hydroxyl radicals ( • OH), and reactive nitrogen species (RNS) to SMT degradation were determined to be 28.70 %, 11.70 %, and 59.60 %, respectively. The contributions of UV irradiation, • OH, and RNS to CBZ degradation were found to be 0.00 %, 96.90 %, and 3.10 %, respectively. A higher dosage of NO 3 − facilitated the degradation of both SMT and CBZ. Solution pH posed almost no effect on SMT degradation, while acidic conditions favored CBZ removal. The degradation of SMT was found to be slightly promoted at low concentrations of Cl − , while the presence of HCO 3 − significantly accelerated the degradation. Cl − , as well as HCO 3 − , retarded the CBZ degradation. Natural organic matter (NOM) as a free radical scavenger and UV irradiation filter posed a substantial inhibitory effect on the degradation of SMT and CBZ. The degradation intermediates and transformation pathways of SMT and CBZ by UV/NO 3 − system were further elucidated. The results showed that the main reaction pathways were bond-breaking reaction, hydroxylation, and nitration/nitrosation reaction. The acute toxicity of most of the intermediates generated during SMT and CBZ degradation was reduced after UV/NO 3 − treatment. After treatment of SMT and CBZ in UV/nitrate system, the DBPs generated in subsequent chlorination were mainly trichloromethane and a small amount of nitrogen-containing DBPs. After bromine ions were introduced in UV/NO 3 − system, a large amount of the originally generated trichloromethane was converted to tribromomethane.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
PubMed
高影响因子
Journal of Water Process Engineering
·
2024
·
IF 6.3
Zhen Tian,Yiyang Li,Lina Wang,Rui Xu,Aihua Wei,Jun He,Chengjun Wang
An innovative technology for the removal of phenolic and non-phenolic organic pollutants from aqueous solution was developed by combining UV 254 irradiation, peroxymonosulfate (PMS), and iodide ions (I − ). Effects of pH, ratio of [I − ]/[PMS], initial concentration of pollutant, dissolved organic matter (DOM) and typical inorganic constituents of environmental water on the degradation of studied pollutants with UV 254 /PMS/I − system were examined. The results showed that pH and [I − ]/[PMS] exhibited significant impact on the degradation of pollutants during UV 254 /PMS/I − process. As the ratio of [I − ]/[PMS] increased from 0.1 to 10.0, the removal efficiencies of phenolic pollutants remarkably increased, but those of non-phenolic pollutants decreased. The DOM at high concentration obviously inhibited the degradation of pollutants during UV 254 /PMS/I − process. Meanwhile, the occurrence of NO 3 − can slightly enhance the degradation of pollutants, and SO 4 2− , Cl − , and HCO 4 − ions had no significant effects on UV 254 /PMS/I − system. The abundant reactive species including OH, SO 4 − , and I /I 2 − during UV 254 /PMS/I − process were generated based on electron spin resonance, fluorescence spectroscopy and steady-state concentration analysis. Quenching experimental results indicated that I /I 2 − can selectively degrade phenolic pollutants via one-electron oxidation. This study provided a reference for the application of reactive radicals involved oxidative technique in water purification .
研究领域:
环境科学
·
水处理技术
✓ 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）