JOURNAL OF HAZARDOUS MATERIALS
·
2021
·
IF 10.588
Tianming Chen,Chao Zou,Fan Chen,Ye Yuan,Jingjing Pan,Qi Zhao,Mansi Wang,Liang Qiao,Haoyi Cheng,Cheng Ding,Aijie Wang
Biocathode systems could be used for in-situ bioremediation of chlorophenols (CPs) in constructed wetland (CW) sediments. However, little is known regarding whether or how cathode burial depths affect the dechlorination of CPs in sediments. Here, 2,4,6-trichlorophenol (2,4,6-TCP)-dechlorinating biocathode systems were constructed under a cathode potential of − 0.7 V (vs. a saturated calomel electrode, SCE) at three different cathode burial depths (5, 10, and 15 cm). The 2,4,6-TCP removal efficiency and average transformation rate with the biocathode increased by 21.46–36.86% and 14.63–34.88% compared to those in the non-electrode groups. Deeper cathode burial depths enhanced the 2,4,6-TCP dechlorination performance. Furthermore, the oxidation-reduction potential (ORP) of the sediment decreased with sediment depth and the applied potential created a more favorable redox environment for the enrichment of functional bacteria. Deeper cathode burial depths also promoted the selective enrichment of electro-active and dechlorinating bacteria (e.g., Bacillus and Dehalobacter , respectively). The biocathode thus served as the carrier, electron source , and regulator of functional bacteria to accelerate the transformation of 2,4,6-TCP (2,4,6-TCP → 2,4-dichlorophenol → 4-chlorophenol → phenol) in sediments. These results offer insights into the effects of cathode burial depth on 2,4,6-TCP dechlorination in sediments from a redox environment and microbial community structure standpoint.
研究领域:
环境科学
·
微生物学
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产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2025
·
IF 5.4
Jinmei Xu,Senqi Xu,Shangqing Tang,Luyao Wang,Kui Wan,Chuqiao Wang
The widespread use and release of 2,4,6-Trichlorophenol (TCP) poses a significant risk to water bodies and ecosystems. Designing efficient and stable catalysts for photocatalytic degradation of TCP remains a great challenge. In this paper, a Z-scheme α-MnO 2 /Bi 2 S 3 (Mn/Bi) composite enriched with oxygen (O Vs ) and sulfur (S Vs ) vacancies is designed for photocatalytic degradation of TCP. 60-Mn/Bi achieved 88 % degradation efficiency for 20 mg/L TCP solution. The reaction rate ( k ) of 60-Mn/Bi is 6.46 and 4.41 times higher than that of α-MnO 2 and Bi 2 S 3 , respectively. The catalyst exhibited high catalytic activity in a wide pH range and high resistance to anion. In addition, the cycling performance of 60-Mn/Bi is relatively stable, and the ion leaching rate is low. The Z-scheme mechanism is confirmed by characterization and DFT, which effectively retained the strong redox capacity. The abundant vacancy structure enhances the adsorption of TCP and promotes the migration of photogenerated carriers. In addition, the rod-shaped Bi 2 S 3 provides a carrier for α-MnO 2 nanoparticles, which effectively alleviates agglomeration and thus exposes more active sites. Three possible degradation pathways were explored by LC-MS and DFT. This study provides a facile method and guidance for the preparation of Z-scheme catalysts to improve photocatalytic degradation performance.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2021
·
IF 7.086
Bingzhi Liu,Tingyu Pan,Jiajun Liu,Li Feng,Yuning Chen,Huaili Zheng
Chlorophenol is a widely used organic compound, and the environmental and health problems caused by it have being worsened in recent years. This study used 2,4,6-trichlorophenol (2,4,6-TCP) as the target pollutant, and employed ultrasound (US) enhanced zero-valent iron (Fe 0 )/EDTA/air system (FEA), namely US/FEA, to remove 2,4,6-TCP. The influence of single factor experimental conditions such as EDTA concentration, Fe 0 dosage, US power, pH and pollutant concentration on the removal efficiency of 2,4,6-TCP was investigated, and the optimal reaction conditions were determined. The mechanism of reactive oxygen species (ROS) produced by US/FEA was explored. The degradation process and removal mechanism of 2,4,6-TCP in the US/FEA were discussed through the determination and analysis of intermediate products. The results showed that US could continuously activate and renew the Fe 0 surface, accelerate its oxidation and corrosion process, and then continuously and stably produce sufficient amounts of Fe 2+ and Fe 3+ . Ultrasonic cavitation effect could reduce the difficulty of O 2 activation reaction, and promote the production of sufficient H 2 O 2 . The addition of EDTA made the system have a wide range of pH applications, and its performance under neutral and alkaline conditions was also superior. The ROS of US/FEA included ·OH, O 2 ·- and Fe(IV), where Fe(IV) was the main contributor to the removal of 2,4,6-TCP. In addition, the degradation of 2,4,6-TCP had two processes including dechlorination and benzene ring opening. First, 2,4,6-TCP was dechlorinated and degraded into phenol. And then, phenol was degraded into small molecular acids by ring-opening, and finally it was mineralized into CO 2 and H 2 O completely. US/FEA is a promising technology for high-efficiency degradation of organic matter and deep environmental purification.
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
CHEMOSPHERE
·
2023
·
IF 8.8
Ying Wang,Wei Jiang,Yanqiang Tang,Zheming Liu,Qingdong Qin,Yan Xu
Nanoscale zero–valent iron (NZVI) has been widely used in rapid remediation of contaminants. However, several obstacles such as aggregation and surface passivation hampered NZVI from further application. In this study, sulfurized nanoscale–zero valent iron supported by biochar (BC–SNZVI) was successfully synthesized and utilized for highly efficient 2,4,6–trichlorophenol (2,4,6–TCP) dechlorination in aqueous solution. SEM-EDS analysis revealed the even distribution of SNZVI on the surface of BC. FTIR, XRD, XPS and N 2 Brunauer–Emmett–Teller (BET) adsorption analyses were carried out to characterize the materials. Results showed that BC–SNZVI with S/Fe molar ratio of 0.088, Na 2 S 2 O 3 as sulfurization agent, and pre–sulfurization as the sulfurization strategy exhibited the superior performance for 2,4,6–TCP removal. The overall removal of 2,4,6–TCP was well described with the pseudo–first–order kinetics (R 2 > 0.9), and the observed kinetics constant K obs was 0.083 min −1 with BC–SNZVI, which was one order of magnitude higher than that of BC–NZVI (0.0092 min −1 ) and SNZVI (0.0042 min −1 ), and two orders of magnitude higher than that of NZVI (0.00092 min −1 ). Moreover, the removal efficiency of 2,4,6–TCP reached 99.5% by BC–SNZVI with dosage of 0.5 g L −1 , initial 2,4,6–TCP concentration of 30 mg L −1 and initial solution pH of 3.0 within 180 min. The removal of 2,4,6–TCP by BC–SNZVI was acid–promoted and the removal efficiencies of 2,4,6–TCP decreased with the increase of initial 2,4,6–TCP concentrations. Furthermore, more extensive dechlorination of 2,4,6–TCP was achieved with BC–SNZVI and complete dechlorination product phenol became predominant. The facilitation of sulfur for Fe 0 utilization and electron distribution in the presence of biochar remarkably enhanced the dechlorination performance of BC–SNZVI for 2,4,6–TCP. These findings provide insights into BC–SNZVI as an alternative engineering carbon based NZVI material for treating chlorinated phenols.
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
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Yanqiang Tang,Ying Wang,Qingdong Qin,Yan Xu
In the anaerobic biocathode, reductive dechlorination of 2,4,6-trichlorophenol (2,4,6-TCP) mainly proceeded to produce 4-monochlorophenol (4-MCP) and phenol, while anaerobic mineralization was challenging. In this study, biocathodes microbial communities were first acclimated via potentials repeatedly adjusted between −0.278 V and +0.200 V (T-200), −0.278 V and +0.400 V (T-400), and −0.278 V and +0.600 V (T-600). Subsequently, all biocathode potentials were stabilized at −0.278 V for the degradation of 2,4,6-TCP. The results revealed that the T-600 achieved the highest degradation rate of 2,4,6-TCP (0.43 d −1 ), outperforming T-200 (0.051 d −1 ), T-400 (0.020 d −1 ), and open-circuit bioreactor (OC, 0.038 d −1 ) groups. In T-600, pare -dechlorination was facilitated, allowing for the conversion of 2,4,6-TCP to 2-monochlorophenol (2-MCP). Additionally, the detection of 4-hydroxybenzoic acid, an anaerobic mineralization intermediate of 2,4,6-TCP, indicated that anaerobic mineralization was also occurring. Polarity reversal occurred only in T-600 during the acclimation period, resulting in alterations to the electrical properties of the biocathode and microbial community. The cyclic voltammetry (CV) and differential pulse voltammetry (DPV) results indicated that there were more electroactive sites in biocathode of T-600, and the bidirectional extracellular electron transfer (EET) might be related to cytochrome. Mycobacterium (24.33% in slurry and 19.92% in biofilm), Thiobacillus (2.47% in slurry and 17.85% in biofilm), and Arenimonas (4.23% in slurry and 4.32% in cathode biofilm) were identified as the dominant electroactive bacteria in T-600, with Mycobacterium also playing an important role in the degradation of chlorophenols. These findings suggested that polarity reversal may represent a viable strategy for constructing microbial communities capable of achieving simultaneous dechlorination and mineralization of 2,4,6-TCP.
研究领域:
环境微生物学
·
电化学工程
✓ 已验证
产品关联
DOI
高影响因子
Desalination and Water Treatment
·
2016
·
IF 1.272
Jie Cui,Xiaoliang Ma,Xiaogang Wu,Xu Zhang
The adsorption of 2,4,6-trichlorophenol (2,4,6-TCP) on synthesized magnetic mesoporous silica (Fe3O4/SiO2/m-SiO2, MMS) composites and the regeneration of its adsorption capacity through direct UV photolysis was performed in this work. MMS exhibited good performance in removing 2,4,6-TCP from aqueous solutions. The adsorption ratio of 2,4,6-TCP was determined to be influenced by aquatic pH, dissolved humic acids, ionic strength, temperature, and the loaded adsorbents. The adsorption isotherm fit the Freundlich and Polanyi–Manes model better than the Langmuir model, which indicated that the adsorption of 2,4,6-TCP was more likely a pore-filling process. The calculated adsorbed capacity for 2,4,6-TCP on MMS was 55 mg/g. Direct UV photolysis could decompose the adsorbed 2,4,6-TCP and later regenerate the adsorption capacity of MMS to a certain degree; however, the outer mesoporous silica layer was not UV-persistent, and large parts of the mesoporous silica layer were also shown to be corrupted from the Fe3O4/SiO2 core. Therefore, after long duration UV irradiation, the adsorption of 2,4,6-TCP on regenerated MMS was much lower than on freshly synthesized MMS. These results suggest that the photostability of magnetic core-shell-like nanocomposites should be investigated because parts of the composites might leach into the bulk phase during practical use and cause potential environmental risks, similar to other well-known nanomaterials.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
CATALYSIS TODAY
·
2013
·
IF 2.98
Xuefeng Hu,Huanhuan Ji,Fei Chang,Yongming Luo
In this study, a rapid reduction of Cr(VI) and degradation of 2,4,6-trichlorophenol (2,4,6-TCP) in a simultaneous manner was reported through the catalysis of g-C 3 N 4 under visible light ( λ > 420 nm) irradiation. The effects of initial concentration of reactants, dissolved O 2 and pH value were investigated systematically. It indicated that, under the optimized concentration, the Cr(VI) reduction and 2,4,6-TCP oxidation could be accomplished in couple of hours in the presence of g-C 3 N 4 . And also, the O 2 involvement and low pH value were able to significantly improve the removal rate of Cr(VI) and 2,4,6-TCP. In addition, the reaction mechanism was investigated through monitoring the reduced states of Cr(VI) and active oxygen intermediates formed during photoreaction by ESR and XPS, as well as determining the degradation products of 2,4,6-TCP by HPLC–MS. The results supported that the redox reactions of Cr(VI) and 2,4,6-TCP can be performed simultaneously via a synergistic oxidation–reduction mechanism in the presence of g-C 3 N 4 under visible light irradiation.
研究领域:
环境科学
·
光催化材料
✓ 已验证
DOI
高影响因子
KOREAN JOURNAL OF CHEMICAL ENGINEERING
·
2014
·Vol. 32
·期 4
·767-776
·
IF 1.241
Yu Ping,Sun Qilong,Li Jianfeng,Tan Zhenjiang,Pan Jianming,Yan Yongsheng
Magnetic molecularly imprinted microspheres (MMIS) were successfully prepared by suspension polymerization, and then as-prepared MMIS were used as adsorbents for selective recognition of 2,4,6-trichlorophenol (2,4,6-TCP) from aqueous solutions. The results composites were characterized by Fourier transform infrared (FT-IR), X-ray diffraction (XRD), thermo gravimetric analysis (TGA), scanning electron microscope (SEM) and vibrating sample magnetometer (VSM). The results demonstrated that MMIS possesses porous spherical morphology, and exhibits good thermal stability and magnetic property (Ms=10.14 emu g -1 ). Then batch mode of binding experiments was used to determine the equilibrium, kinetics and selectivity recognition. The Langmuir isotherm model fitted the equilibrium data better than did the Freundlich model, and the maximum adsorption capacity on MMIS was about 1.7 times higher than that of MNIS. Kinetics behaviors of MMIS were well described by the pseudo-second-order model. MMIS possessed outstanding selectivity recognition for 2,4,6-TCP in the presence of other competitive phenols (such as sesamol, 3-CP, thymol, 2,4-DCP). Furthermore, the reusability performance of MMIS showed about 17.53% loss after five repeated cycles. Finally, the MMIS were successfully applied to the selective extraction of 2,4,6-TCP from the vegetable samples.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2022
·
IF 14.224
Yanqiang Tang,Jiafeng Chen,Zhixing Xiao,Zheming Liu,Lei Xu,Qingdong Qin,Yuqiao Wang,Yan Xu
The extracellular electron transfer (EET) is regarded as one of the crucial factors that limit the application of the bioelectrochemical system (BES). In this study, two different solid-phase redox mediators (RMs), biochar (1.2 g/L, T-B) and humin (1.2 g/L, T-H) were used for boosting the microorganisms accessing the electrons required for 2,4,6-TCP dechlorination under weak electrical stimulation (−0.278 V vs. Standard hydrogen electrode). BES with dissolved RM anthraquinone-2,6-disulfonate (AQDS 0.5 mmol/L, T-A) was used as a comparison. The results showed that dechlorination of 2,4,6-TCP could be greatly accelerated by biochar (1.78 d −1 ) and humin (1.50 d −1 ) than AQDS (0.24 d −1 ) and no RM control (T-M, 0.27 d −1 ). Moreover, phenol became the predominant dechlorination product in T-H (78.5 %) and T-B (63.0 %) instead of 4-CP in T-M (67.1 %) and T-A (89.8 %). Pseudomonas , Sulfurospirillum , Desulfuromonas , Dehalobacter , Anaeromyxobacter , and Dechloromonas belonging to Proteobacteria or Firmicutes rather than Chloroflexi might be responsible for the dechlorination activity. Notably, different RMs tended to stimulate distinct electroactive bacteria. Pseudomonas was the most abundant microorganism in T-M (41.92 %) and T-A (17.24 %), while Rhodobacter was most prevalent in T-H (20.04 %) and Azonexus was predominant in T-B (48.48 %). This study is essential in advancing the understanding of EET in BES for microbial degradation of organohalide contaminants under weak electrical stimulation.
研究领域:
环境科学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Desalination and Water Treatment
·
2016
·
IF 1.272
Quan Zhang,Fei-yun Sun,Wen-yi Dong,Ru-bing Han,Lei Liu
A laboratory-scale flat-sheet membrane bioreactor (MBR) was employed to treat real micro-polluted surface water loaded with 2,4,6-trichlorophenol (2,4,6-TCP). MBR treatment performances were evaluated in terms of dissolved organic matters (DOM) degradation, target trace organic (2,4,6-TCP) removal, and effluent bio-stability improvement. The experimental results showed that the removal efficiency of DOM related closely with the biomass content in MBR. With continuous growth and accumulation of biomass under a long sludge retention time (SRT), stable DOM removal efficiency above 50% could be obtained, resulted in an effluent DOM kept below 2.0 mg TOC/L. Upon the steady state of MBR, more than 90% 2,4,6-TCP was removed by synergistic function of aeration volatilization, biological degradation, and activated sludge adsorption. The removal pathways of 2,4,6-TCP were specified by series of batch-scale trials, and corresponding contributions were estimated. It was revealed that fresh ultrafiltration rejection took a major responsible for 2,4,6-TCP removal in the start-up phase, which rejected about 15% 2,4,6-TCP. In comparison, for a steady state where had a high biomass content around 450 mg/L, biodegradation was the main pathway for 2,4,6-TCP removal, reflected by that above 300 μg/L 2,4,6-TCP was eliminated by microorganism degradation within no more than 1.2 h. The results herein claimed that MBR is a feasible way to treat micro-polluted water resource, and its removal pathway specification gave reliable guidance for MBR application.
研究领域:
环境工程
·
水处理技术
✓ 已验证
DOI
高影响因子
LUMINESCENCE
·
2019
·Vol. 34
·期 7
·680-688
·
IF 1.691
Yang Liu,Piaopiao Chen,Shan Zheng,Yichen Xing,Chaobiao Huang
In this study, a high fluorescence sensitivity and selectivity, molecularly imprinted nanofluorescent polymer sensor (MIP@SiO 2 @QDs) was prepared using a reverse microemulsion method. 2,4,6-Trichlorophenol (2,4,6-TCP) was detected using fluorescence quenching. Tetraethyl orthosilicate (TEOS), quantum dots (QDs) and 3-aminopropyltriethoxysilane (APTS) were used as cross-linker, signal sources and functional monomer respectively. The sensor (MIP@SiO 2 @QDs) and the non-imprinted polymer sensor (NIP@SiO 2 @QDs) were characterized using infra-red (IR) analysis, X-ray diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The selectivity of MIP@SiO 2 @QDs was examined by comparing 2,4,6-TCP with other similar functional substances including 2,4-dichlorophenol (2,4-DCP), 2,6-dichlorophenol (2,6-DCP) and 4-chlorophenol (4-CP). Results showed that MIP@SiO 2 @QDs had better selectivity for 2,4,6-TCP than the other compounds. Fluorescence quenching efficiency displayed a good linear response at the 2,4,6-TCP concentration range 5–1000 μmol/L. The limit of detection (LOD) was 0.9 μmol/L (3σ, n = 9). This method was equally applicable for testing actual samples with a recovery rate of 98.0–105.8%. The sensor had advantages of simple pretreatment, good sensitivity and selectivity, and wide linear range and could be applied for the rapid detection of 2,4,6-TCP in actual samples.
研究领域:
分析化学
·
环境科学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2012
·Vol. 2
·期 32
·12378-12383
·
IF 0
Xuefeng Hu,Huanhuan Ji,Lei Wu
Pure and Pt nanoparticle-modified rutile TiO2 were synthesized via hydrolysis of TiCl4 in the absence or presence of Pt nanoparticles. HRTEM, XRD, and SEM were used to characterize the structure of the prepared catalysts. The resulting modified TiO2 catalysts show extended visible light absorbance. Photodegradation of 2,4,6-trichlorophenol (2,4,6-TCP) over these photocatalysts was investigated under visible light illumination. The Pt nanoparticles facilitate the separation of photogenerated electron–hole pairs at low Pt content, then enhances the photodegradation rate of 2,4,6-TCP. 0.18Pt–TiO2 achieved the best photocatalytic activity among the tested catalysts. It was found that singlet oxygen rather than ˙OH acts as the main oxidative species for the degradation of 2,4,6-TCP according to the experimental results. The degradation intermediates of 2,4,6-TCP were identified and the degradation pathway was proposed. Pt nanoparticles on TiO2 significantly enhance O2 adsorption and the formation of ˙O2−. The rutile surface is a favorable condition for stabilizing ˙O2−. These properties of the Pt nanoparticle-modified rutile TiO2 facilitate the formation of 1O2via the reaction of superoxide anions with holes.
研究领域:
环境科学
·
材料科学
·
光催化技术
✓ 已验证
产品关联
DOI
危险品化学品经营许可证（带存储）