WATER RESEARCH
·
2024
·
IF 11.4
Yang Yu,Ang Li,Sheng-Qiang Fan,He-Ping Zhao
Dissimilatory iron-reducing bacteria (DIRB) with extracellular electron transfer (EET) capabilities have shown significant potential for bioremediating halogenated hydrocarbon contaminated sites rich in iron and humic substances. However, the role and microbial molecular mechanisms of iron-humic acid (Fe-HA) complexes in the reductive dehalogenation process of DIRB remains inadequately elucidated. In this study, we developed a sustainable carbon cycling approach using Fe-HA complexes to modulate the electron flux from sawdust (SD), enabling almost complete reductive dechlorination by most DIRB (e.g., Shewanella oneidensis MR-1) that lack complex iron-sulfur molybdo enzymes. The SD-Fe-HA/MR-1 system achieved a 96.52% removal efficiency of tetrachloroethylene (PCE) at concentrations up to 250 μmol/L within 60 days. Material characterization revealed that DIRB facilitated the hydrolysis of macromolecular carbon sources by inducing the formation of amorphous ferrihydrite (FeOOH) in Fe-HA complexes. More importantly, the bioavailable FeOOH activated additional intracellular electron flow pathways, increasing the activity of potential dehalogenases. Transcriptome further highlight the innovative role of biogenic amorphous FeOOH in integrating intracellular redox metabolism with extracellular charge exchange to facilitate reductive dechlorination in DIRB. These findings provide novel insights into accelerating reductive dechlorination in-situ contaminated sites lacking obligate dehalogenating bacteria.
研究领域:
环境微生物学
·
污染修复
✓ 已验证
DOI
高影响因子
Journal of Cleaner Production
·
2019
·
IF 6.395
Shenglei Sun,Yue Gao,Jianwei Zhang,Baoyu Gao,Qinyan Yue,Wei Zhang,Zhihao Lu,Xiaohua Zhu
The effective coagulation aid epichlorohydrin-dimethylamine was synthesized, its co-effect with three ferric iron species in polyferric chloride on humic acid elimination and membrane pollution in coagulation-ultrafiltration hybrid technique were appraised to improve the hybrid water treatment technology and generate cleaner water production by this research. To be specific, dosages of polyferric chlorides 2 and polyferric chlorides&epichlorohydrin-dimethylamine were adjusted according to their coagulation performance in jar tests. Furthermore, properties of generated flocs such as floc size (median particle diameter), strength/recovery factor and fractal dimension feature were monitored and combined with results of membrane fouling resistance under various shear forces to understand the mechanism of membrane fouling. Results indicated that epichlorohydrin-dimethylamine can observably enhance the coagulation performance of all polyferric chlorides, especially at low dosage of 4 mg/L. The higher the epichlorohydrin-dimethylamine dosage, the higher removal efficiencies achieved. In particular, for polyferric chloride with basicity of 1.5, the removal efficiency for dissolved organic carbon raised approximately from 15% to 32% as epichlorohydrin-dimethylamine dosage increased from zero to 1.5 mg/L. Meanwhile, for ultra-membrane 3 applied in this study, addition of the epichlorohydrin-dimethylamine also significantly reduced the total membrane fouling resistance of all coagulated water samples by forming cake layer of low compactness and reducing residual micro-particles, 4 even when shearing forces was introduced. Thereinto, the total membrane fouling resistance reduction of polyferric chloride with basicity of 1.5 was the most obvious, which dropped from 2.8 × 10 8 m −1 to 2.3 × 10 8 m −1 , approximately.
研究领域:
环境科学
·
水处理工程
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL RESEARCH
·
2011
·
IF 0.55
Yong-Rui Pi,Jun Tan,Hui Liu,Jie Chen,Zhu-You Qun,Yan-Bo Zeng,Lei Li
Catalytic cracking reaction of 1,2-dimethyl-1,1,2,2-tetrachlorodisilane with a halobenzene (PhCl, PhBr) to prepare methylphenyldichlorosilane has been investigated. Pd(PPh3)4 exhibited the best catalytic activity among the catalysts used. The activity of chlorobenzene was significantly lower than that of bromobenzene. With the latter and toluene as solvent, in the presence of 0.3 mol % Pd(PPh3)4, the conversion of disilane was 100% with a selectivity to MePhSiCl2 of 97.1%.
研究领域:
有机化学
·
催化化学
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2019
·
IF 3.375
Peng Cui,Changtong Song,Xianhong Zhang,Dong Chen,Yuhong Ma,Wantai Yang
The controlled radical polymerization (CRP) of vinyl chloride monomer (VCM), a low activity monomer with high radical reactivity, is still a true challenge. In this study, a novel CRP of VCM with high monomer conversion at 45 °C with xanthene-9-thione (XT) as mediator and bis(4-tert-butylcyclohexyl)peroxydicarbonate (TBCP) as initiator is achieved. The Mn of the produced poly(vinyl chloride) (PVC) increases slightly with increasing monomer conversion and could be mediated in the range from 6k to 12k by simply changing the molar ratio of TBCP/XT while the dispersity maintains around 2.0. The fidelity of XT dormant groups of PVC-XT is about 60–80% and depends on the ratio of TBCP/XT. With the as-prepared PVC-XT as macroinitiator, block copolymerizations of methyl methacrylate (MMA), n-butyl acrylate (BA), and styrene (St) are carried out and the PVC-b-PMMA, PVC-b-PBA, and PVC-b-PSt block copolymers have been synthesized successfully.
研究领域:
高分子化学
·
材料科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2016
·
IF 5.31
Wen-Long Wang,Qian-Yuan Wu,Zhi-Ming Li,Yun Lu,Ye Du,Ting Wang,Nan Huang,Hong-Ying Hu
Carbamazepine (CBZ) is a ubiquitous micropollutant in wastewater and reclaimed water. In this study, we evaluated CBZ degradation by light-emitting diode (LED)-driven UV/chlorine oxidation. Under LED irradiation of 280 nm (LED280) and 310 nm (LED310), UV/chlorine could efficiently degrade CBZ. Compared with LED UV/H 2 O 2 treatment, LED UV/chlorine oxidation achieved a CBZ degradation rate that was one order of magnitude higher. The CBZ degradation followed pseudo-first-order kinetics, and the rate constants ( k obs,CBZ ) for LED280 UV/chlorine and LED310 UV/chlorine increased from 0.072 to 0.91 min −1 and 0.044 to 0.65 min −1 , respectively, when chlorine dosage increased from 0.07 to 0.14 mM. Under neutral conditions, the generated OH and Cl accounted for over 80% of the CBZ degraded by LED UV/chlorine. The maximum k obs,CBZ for LED UV/chlorine was observed at pH 8.5; k obs,CBZ decreased when solution pH increased to 9.5 or decreased to 5.5. This is because the main UV-absorbing chlorine species in the LED280 and LED310 systems is OCl − , which is different from those in low-pressure mercury lamp/chlorine systems. The acute toxicity for CBZ solution treated by LED UV/chlorine increased at lower fluence (<752 mJ/cm 2 ) and decreased at higher fluence (>1233 mJ/cm 2 ). However, the cytotoxicity to Chinese hamster ovary cells and adsorbable organic halide content of CBZ solution both increased after chlorination and LED UV/chlorine. The lowest electrical cost for the degradation of CBZ by LED UV/chlorine occurred under neutral conditions with a chlorine dosage of 0.4–0.7 mM (28.4–49.7 mg/L).
研究领域:
环境科学
·
水处理技术
·
毒理学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
·
2016
·
IF 3.131
Shizong Wang,Jianlong Wang,Yuliang Sun
Chlorinated paraben, namely, methyl 3, 5-dichloro-4-hydroxybenzoate (MDHB) is the by-product of chlorination disinfection of paraben and frequently detected in the aquatic environments, which exhibited higher persistence and toxicity than paraben itself. In this paper, the combined irradiation and biological treatment process was employed to investigate the removal of MDHB from aqueous solution. The results showed that the removal efficiency of MDHB and total organic carbon (TOC) by irradiation process increased with radiation dose no matter what the initial concentration of MDHB was. The maximum removal efficiency of MDHB was 100%, 91.1%, 93%, respectively, for the initial concentration of MDHB of 1 mg/L, 5 mg/L and 10 mg/L with the radiation dose of 800 Gy. However, the maximum removal efficiency of TOC among all the experimental groups was only 15.3% obtained with the initial concentration of 1 mg/L at dose of 800 Gy. The subsequent biological treatment enhanced the mineralization of MDHB. The suitable radiation dose for the subsequent biological treatment was determined to be 600 Gy. In this case the removal efficiency of TOC increased to about 70%. Compared to the single biological treatment, the integrated irradiation and biological treatment significantly increase the degradation and mineralization of MDHB. Moreover, the dechlorination efficiency reached 77.4% during the integrated irradiation and biological treatment process. In addition, eight intermediates were identified during the combined process and the possible degradation pathway was proposed.
研究领域:
环境科学
·
生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF SEPARATION SCIENCE
·
2015
·Vol. 38
·期 24
·4204-4210
·
IF 2.737
Guilong Peng,Ying Lu,Qiang He,Daniel Mmereki,Guangming Zhou,Junhua Chen,Xiaohui Tang
A novel low-density solvent-based vortex-assisted surfactant-enhanced-emulsification liquid–liquid microextraction with the solidification of floating organic droplet method coupled with high-performance liquid chromatography was developed for the determination of 3,5,6-trichloro-2-pyridinol, phoxim and chlorpyrifos-methyl in water samples. In this method, the addition of a surfactant could enhance the speed of the mass transfer from the sample solution into the extraction solvent. The extraction solvent could be dispersed into the aqueous by the vortex process. The main parameters affecting the extraction efficiency were investigated and the optimum conditions were established as follows: 80 μL 1-undecanol as extraction solvent, 0.2 mmol/L of Triton X-114 selected as the surfactant, the vortex time was fixed at 60 s with the vortex agitator set at 3000 rpm, the concentration of acetic acid in sample solution was 0.4% v/v and 1.0 g addition of NaCl. Under the optimum conditions, the enrichment factors were from 172 to 186 for the three analytes. The linear ranges were from 0.5 to 500 μg/L with a coefficient of determination ( r 2 ) of between 0.9991 and 0.9995. Limits of detections were varied between 0.05 and 0.12 μg/L. The relative standard deviations ( n = 6) ranged from 0.26 to 2.62%.
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
ULTRASONICS SONOCHEMISTRY
·
2014
·
IF 3.816
Deming Zhao,Yiya Zheng,Min Li,Shams Ali Baig,Donglei Wu,Xinhua Xu
In this study, nickle/iron (Ni/Fe) nanoparticles were synthesized by liquid phase reductive method in the presence of 20 kHz ultrasonic irradiation to improve nanoparticles’ disparity and avoid agglomeration. The characterized results showed that this method has obviously modified most of the particles in term of sizes and specific surface areas. Meanwhile, the improved nanoscale Ni/Fe particles were employed for the reductive dechlorination of 2,4-dichlorophenol (2,4-DCP) as a function of some influential factors (Ni content, Ni/Fe nanoparticles dosage, reaction temperature and initial pH values) and degradation path. Experimental results showed that 2,4-DCP was first adsorbed by Ni/Fe nanoparticles, then quickly reduced to o -chlorophenol ( o -CP), p -chlorophenol ( p -CP), and finally to phenol (P). The application of ultrasonic irradiation for Ni/Fe nanoparticles synthesis was found to significantly enhance the removal efficiency of 2,4-DCP. Consequently, the phenol production rates increased from 68% (in the absence of ultrasonic irradiation) to 87% (in the presence of ultrasonic irradiation) within 180 min. Nearly 96% of 2,4-DCP was removed after 300 min reaction with these optimized conditions: Ni content over Fe 0 3 wt%, initial 2,4-DCP concentration 20 mg L −1 , Ni/Fe dosage 3 g L −1 , initial pH value 3.0, and reaction temperature 25 °C. The degradation of 2,4-DCP followed pseudo-first-order kinetics reaction and the apparent pseudo-first-order kinetics constant was 0.0737 min −1 . This study suggested that the presence of ultrasonic irradiation in the synthesis of nanoscale Ni/Fe particles could be a promising technique to enhance nanoparticle’s disparity and avoid agglomeration.
研究领域:
环境科学
·
纳米材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
·
2022
·
IF 9.224
Shuhao Wei,Yiyang Qiu,Xiucheng Sun,Xiaolong Wang,Haitao Li,Guojun Lan,Jian Liu,Ying Li
Conversion of waste plastics into high value carbon materials is of great importance for sustainable development. Herein, we propose a new approach to prepare sustainable nanoporous carbon catalysts (NPCs) with high catalytic performance for acetylene hydrochlorination by using waste poly(vinyl chloride) (PVC) as carbon source via a solid grinding method with the assistance of melamine. The addition of melamine not only makes the dechloridation of PVC occur easily at room temperature but also greatly improves the yield of carbon products. The nitrogen and defective sites of the NPCs can be easily adjusted by tuning the amount of melamine. Furthermore, NPCs as a carbon catalyst show superior catalytic performance in acetylene hydrochlorination, and the generated vinyl chloride (VCM) can be polymerized to produce PVC, which realizes the recycling of materials.
研究领域:
材料科学
·
环境科学
·
化学工程
·
催化
✓ 已验证
DOI
高影响因子
Toxics
·
2024
·Vol. 12
·期 11
·808
·
IF 3.9
Dongmei Yang,Jiale Huang,Fenli Min,Huixian Zhong,Jialu Ling,Qun Kang,Zhaohua Li,Lilian Wen
In this study, samples from the Yangtze River, Han River, and Liangzi Lake in Wuhan City were utilized to characterize the formation of disinfection by-products (DBPs) from chlorine-based disinfection residues in drinking water sources. The results indicated that the main DBPs in drinking water sources were trichloromethane (TCM) and trichloroacetic acid (TCAA). The generation of DBPs was significantly positively correlated with oxidative substances, aromatic compounds, pH, and ammonia nitrogen (NH 3 -N) content in the water. The concentration of TCAA increased from 0 to 2.45 ± 0.31 mg/L when the reaction time increased to 72 h. As the NaClO concentration increased from 5 mg/L to 15 mg/L, the concentrations of TCAA, TBM, and DCAN increased from 2.03 ± 0.04 mg/L, 0 mg/L, and 0 mg/L to 2.49 ± 0.34 mg/L, 0.21 ± 0.07 mg/L, and 0.10 ± 0.04 mg/L before decreasing to 1.75 ± 0.19 mg/L, 0.17 ± 0.07 mg/L, and 0.04 ± 0.05 mg/L, respectively. The orthogonal experimental results showed that Br − , NH 3 -N, and pH all had significant influences on the TCM generation, whereas temperature affected the formation of TCAA in the Han River. This work reveals the factors influencing the generation of DBPs from chlorine-based disinfection residues, offering a prevention and control method for DBPs in drinking water sources from a theoretical perspective.
研究领域:
环境科学
·
水处理
·
公共卫生
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COORDINATION CHEMISTRY
·
2014
·
IF 2.212
Yu Jin,Chun-Hua Yu,Wen Zhang
Protonated benzylamine and its N-methylated derivatives, [C6H5CH2NH3−n(CH3)n]+ (n = 0−3), have been adopted as cations in chlorocadmate(II) and chlorocuprate(II) complexes, showing inorganic–organic hybrid architectures. For the Cd(II) compounds, the anionic structures vary from perovskite-type layers (n = 0) to chains (n = 1–3). For Cu(II) compounds, the anionic structures range from perovskite-type layers (n = 0), chains (n = 1) to mononuclear species (n = 2–3). Coordination geometries of the metal ions and intermolecular interactions have been analyzed. Their dielectric properties have been measured.
研究领域:
无机化学
·
材料科学
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL POLLUTION
·
2020
·
IF 6.793
Xulei Zhao,Teng Zhang,Junhe Lu,Lei Zhou,Jean-Marc Chovelon,Yuefei Ji
Sulfate radical (SO 4 − )-based advanced oxidation processes (SR-AOPs) are promising in-situ chemical oxidation technologies widely applied for soil/groundwater remediation. The presence of non-target water constituents may interfere the abatement of contaminants by SR-AOPs as well as result in the formation of unintended byproducts. Herein, we reported the formation of toxic chloronitrophenols during thermally activated persulfate oxidation of 2-chlorophenol (2CP) in the presence of nitrite (NO 2 − ). 2-Chloro-4-nitrophenol (2C4NP) and 2-chloro-6-nitrophenol (2C6NP) were identified as nitrated byproducts of 2CP with total yield up to 90%. The formation of nitrated byproducts is a result of coupling reaction between 2CP phenoxyl radical (ClPhO ) and nitrogen dioxide radical (NO 2 ). As a critical step, the formation of ClPhO was supported by density functional theory (DFT) computation. Both 2C4NP and 2C6NP could convert to 2-chloro-4,6-dinitrophenol (2C46DNP) upon further treatment via a denitration-renitration process. The formation rate of 2C4NP and 2C6NP was closely dependent on the concentration of NO 2 − , solution pH, and natural water constituents. ECOSAR calculation suggests that chloronitrophenols are generally more hydrophobic and ecotoxic than 2CP. Our result therefore reveals the potential risks in the abatement of chlorophenols by SR-AOP, particularly when high level of NO 2 − is present in water matrix.
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）