Environmental Chemistry
·
2012
·Vol. 9
·期 6
·558-563
·
IF 2.57
Lei Wu,Xuefeng Hu,Lei Wu,Xuefeng Hu
Environmental context Aromatic amines are widely used chemicals, which show enhanced toxicity and longer environmental persistence when halogenated. We investigated the chlorination of aniline in seawater and in natural aqueous solutions containing Fe3+ and Cl–, under simulated sunlight irradiation. The results increase our understanding of the transformation pathway of typical nitrogen-containing aromatic contaminants in the environment. Photochlorination of aniline was observed in aqueous solutions containing dissolved FeIII and chloride ions under simulated solar light irradiation. Effects of O2, Cl–, Fe3+ and pH on the formation of chloroanilines (CAs) were investigated. para-chloroaniline (4CA) was identified as the main chlorinated product. The formation of 4CA is enhanced with increased concentrations of Cl– or Fe3+, and decreased pH, whereas oxygen plays a negligible role in the process. The results indicate that, Cl• is formed mainly by the photodissociation of FeCl2+–FeCl2+ complexes, and reacts with Cl– to produce Cl2•–. Aniline is then oxidised by Cl2•– into an anilino radical cation, which further reacts with Cl2•– to generate CAs. The photochlorination of aniline in natural seawater was also observed. Other phototransformation products of aniline were detected and a transformation pathway was proposed. This work provides evidence for the photochemical chlorination path of aniline-based aromatic amines in aqueous solutions.
研究领域:
环境科学
·
化学
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2017
·Vol. 24
·期 23
·19031-19043
·
IF 2.741
Mubeen Ishrat,Buekens Alfons,Chen Zhiliang,Lu Shengyong,Yan Jianhua
Municipal solid waste incineration (MSWI) fly ash has been classified as hazardous waste and needs treatment in an environmentally safe manner. Mechanochemical (MC) treatment is such a detoxification method, since it destroys dioxins and solidifies heavy metals. Milling, however, also introduces supplemental metals (Fe, Ni, Cr, Mn…), following wear of both steel balls and housing. Milling moreover reduces the particle size of fly ash and disperses catalytic metal, potentially rising the reactivity of fly ash to form and destroy ‘dioxins’, i.e. polychlorinated dibenzo- p -dioxins and dibenzofurans (PCDD + PCDF or PCDD/F). To test this issue, model fly ash (MFA) samples were composed by mixing of silica, sodium chloride, and activated carbon, and doped with CuCl 2 . Then, these samples were first finely milled without any additives for 0 h (original sample), 1 h and 8 h, and the effect of milling time (and hence particle size) was investigated on the formation of polycyclic aromatic hydrocarbons (PAHs), and of polychlorinated phenols (CP), benzenes (CBz), biphenyls (PCB) and dioxins (PCDD + PCDF) during de novo tests at 300 °C for 1 h, thus simulating the conditions prevailing in the post-combustion zone of an incinerator, where dioxins are formed and destroyed. These compounds are all characterized by their rate of generation (ng/g MFA) and their signature, i.e. internal distribution over congeners as a means of gathering mechanistic indications. PAH and CBz total yield did not decrease in MC treated MFA with milling time, while total pentachlorophenol (PeCP), PCB and PCDD/F yield decreased up to 86, 94 and 97%, respectively. International Toxic Equivalents (I-TEQ) concentration decreased more than 90%, while degree of chlorination varied inconsistently for PCB and PCDD/F, and average congener patterns of PCDD/F do not vary considerably with milling time for both gas and solid phase.
研究领域:
环境科学
·
化学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2014
·
IF 4.331
Hao Jin,Chao Wang,Jiaqi Shi,Lei Chen
The individual IC 50 (the concentrations causing a 50% inhibition of bioluminescence after 15 min exposure) of cadmium ion (Cd) and nine chlorinated anilines to Photobacterium phosphoreum ( P. phosphoreum ) were determined. In order to evaluate the combined effects of the nine chlorinated anilines and Cd, the toxicities of chlorinated anilines combined with different concentrations of Cd were determined, respectively. The results showed that the number of chlorinated anilines manifesting synergy with Cd decreased with the increasing Cd concentration, and the number manifesting antagonism decreased firstly and then increased. The joint toxicity of mixtures at low Cd concentration was weaker than that of most binary mixtures when combined with Cd at medium and high concentrations as indicated by TU Total . QSAR analysis showed that the single toxicity of chlorinated anilines was related to the energy of the lowest unoccupied molecular orbital ( E LUMO ). When combined with different concentrations of Cd, the toxicity was related to the energy difference ( E HOMO − E LUMO ) with different coefficients. Van der Waals’ force or the complexation between chlorinated anilines and Cd had an impact on the toxicity of combined systems, which could account for QSAR models with different physico-chemical descriptors.
研究领域:
环境科学
·
毒理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF SEPARATION SCIENCE
·
2016
·Vol. 39
·期 11
·2146-2155
·
IF 2.741
Xiuzhi Bai,Ting Zhang,Haipu Li,Zhaoguang Yang
Chloroanisoles, particularly 2,4,6-trichloroanisole, are commonly identified as major taste and odor compounds in water. In the present study, a simple and efficient method was established for the simultaneous determination of chloroanisoles and the precursor 2,4,6-trichlorophenol in water by using low-density-solvent-based simultaneous dispersive liquid–liquid microextraction and derivatization followed by gas chromatography with electron capture detection. 2,4-Dichloroanisole, 2,6-dichloroanisole, 2,4,6-trichloroanisole, 2,3,4-trichloroanisole, and 2,3,6-trichloroanisole were the chloroanisoles evaluated. Several important parameters of the extraction-derivatization procedures, including the types and volumes of extraction solvent and disperser solvent, concentrations of derivatization agent and base, salt addition, extraction-derivatization time, and temperature were optimized. Under the optimized conditions (80 μL of isooctane as extraction solvent, 500 μL of methanol as disperser solvent, 60 μL of acetic anhydride as derivatization agent, 0.75% of Na 2 CO 3 addition w/v, extraction-derivatization temperature of 25°C, without salt addition), a good linearity of the calibration curve was observed by the square of correlation coefficients ( R 2 ) ranging from 0.9936 to 0.9992. Repeatability and reproducibility of the method were < 4.5% and <7.3%, respectively. Recovery rates ranged from 85.2 to 101.4%, and limits of detection ranged from 3.0 to 8.7 ng/L. The proposed method was applied successfully for the determination of chloroanisoles and 2,4,6-trichlorophenol in water samples.
研究领域:
分析化学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMOSPHERE
·
2022
·
IF 8.943
Yufan Zhang,Pu Ma,Heyun Fu,Xiaolei Qu,Shourong Zheng
Chloroanisoles is a class of odorous pollutants commonly identified in drinking water . In the present study, we confined noble metal palladium (Pd) in the micropores of zeolite Y ( ie -Pd@Y) using an ion exchange method, and applied it for the catalytic hydrodechlorination removal of chloroanisoles (represented by 2,4,6-trichloroanisole/TCA) in water. Pd supported on zeolite Y surface ( im -Pd/Y, prepared by conventional impregnation method) was used as the benchmarking catalyst. The characterization results revealed that ie -Pd@Y had smaller Pd particle size and higher Pd n+ /Pd 0 ratio than im -Pd/Y. The catalytic hydrodechlorination of TCA followed a concerted dechlorination pathway and the Langmuir-Hinshelwood model. The ie -Pd@Y catalysts with different Pd loadings exhibit excellent catalytic activities with more than 95% of TCA removed within 30 min, which is far superior to the im -Pd/Y catalysts (27–70%). Moreover, due to the confinement effect of zeolite Y, ie -Pd@Y displayed enhanced catalytic stability as compared with im -Pd/Y. The initial activity of ie -Pd@Y was more than 20 times higher than that of im -Pd/Y after five reaction cycles. Additionally, with the assistance of sieving effect, ie -Pd@Y displayed much stronger capability against the interference from dissolved organic matter than im -Pd/Y. The present results demonstrate that the confined catalysts ie -Pd@Y can be applied in liquid phase catalytic hydrogenation to effectively eliminate halogenated odorants in waters.
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
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2025
·
IF 11.3
Jiafu Li,Tian Qiu,Wenshan Shi,Caroline O. Granger,Md. Tareq Aziz,Patrick T. Justen,Susan D. Richardson
Aromatic disinfection byproducts (DBPs) can account for up to 36% of total organic halogen (TOX) in chlorinated drinking water and may be key drivers of developmental toxicity. However, aromatic DBPs reported to date cannot fully explain the observed TOX or developmental toxicity of drinking water. In this study, 17 chlorobenzenediols were identified in chlor(am)inated drinking water using gas chromatography–high resolution mass spectrometry (GC-HRMS). Total concentrations of chlorobenzenediols in tap water from seven cities ranged from 15 to 116 ng/L, with a mean of 54 ng/L. These levels are higher than previously reported for eight classes of aromatic DBPs and halobenzoquinones. Eleven chlorobenzenediols also formed during chlor(am)ination of Suwannee River natural organic matter (NOM), indicating that NOM is an important precursor. Five chlorobenzenediols have a reported LC50 and/or EC50 of less than 1 mg/L for various organisms, indicating that they are classified as very toxic chemicals and are likely to be among the most developmentally toxic aromatic DBPs discovered. Considering that the chlorobenzenediol concentrations in drinking water were higher than eight classes of reported aromatic DBPs and halobenzoquinones, they are likely to have a much more significant impact on drinking water developmental toxicity than other known aromatic DBPs.
研究领域:
环境毒理学
·
分析化学
·
环境卫生学
·
分子毒理学
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水质安全
·
发育生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL POLLUTION
·
2013
·
IF 3.73
Deyang Kong,Qing Xia,Guoqiang Liu,Qingguo Huang,Junhe Lu
Covalent coupling to natural humic constituents comprises an important transformation pathway for anilinic pollutants in the environment. We systematically investigated the reactions of chlorine substituted anilines with catechol and syringic acid in horseradish peroxidase (HRP) catalyzed systems. It was demonstrated that although nucleophilic addition was the mechanism of covalent bonding to both catechol and syringic acid, chloroanilines coupled to the 2 humic constituents via slightly different pathways. 1,4-addition and 1,2-addition are involved to catechol and syringic acid, respectively. 1,4-addition showed empirical 2nd order kinetics and this pathway seemed to be more permanent than 1,2-addition. Stability experiments demonstrated that cross-coupling products with syringic acid could be easily released in acidic conditions. However, cross-coupling with catechol was relatively stable at similar conditions. Thus, the environmental behavior and bioavailability of the coupling products should be carefully assessed.
研究领域:
环境化学
·
有机化学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Advanced Energy Materials
·
2022
·Vol. 12
·期 20
·2200417
·
IF 29.698
Yao Dong,Wenjian Shen,Wei Dong,Cong Bai,Juan Zhao,Yecheng Zhou,Fuzhi Huang,Yi-Bing Cheng,Jie Zhong
The interfacial properties for the buried junctions of the perovskite solar cells (PSCs) play a crucial role for the further enhancement of the power conversion efficiency (PCE) and stability of devices. Delicate manipulation of the interface properties such as the defect density, energy alignment, perovskite film quality, etc., guarantees efficient extraction and transport of photogenerated carriers. Herein, chlorobenzenesulfonic potassium salts are presented as a novel multifunctional agent to modify the buried tin oxide (SnO 2 )/perovskite interface for regular PSCs. The increasing number of carbon-chlorine bonds (C Cl) in 2,4,5-trichlorobenzenesulfonic potassium (3Cl-BSAK) exhibit efficient interaction with uncoordinated Sn, effectively filling oxygen vacancies in the SnO 2 surface. Importantly, synergistic effects of the functional group-rich organic anions and the potassium ion are achieved for reduced defect density, carrier recombination, and hysteresis. A champion PCE of 24.27% and the open-circuit voltage ( V OC ) up to 1.191 V for modified devices are obtained. The unencapsulated devices maintain 80% of their initial PCE after aging at 80 °C for 800 h in the atmosphere and 95% after aging for 100 d. With 3Cl-BSAK decoration, a high efficiency semitransparent PSC with a PCE of 12.83% and an average visible light transmittance (AVT) over 27% is also obtained.
研究领域:
光伏技术
·
材料科学
·
能源材料
·
半导体界面
·
可再生能源
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）