SEPARATION AND PURIFICATION TECHNOLOGY
·
2015
·
IF 3.091
Jing Zhang,Yao Wu,Liping Liu,Yeqing Lan
The degradation of p -chloronitrobenzene ( p CNB) in different systems including ozone alone, ozone together with zero-valent zinc (Zn(0)) and Zn(0) bubbled with air instead of ozone was investigated. The results demonstrated that the degradation of p CNB by ozone alone was weak. However, the coexistence of Zn(0) and ozone exhibited a significantly synergistic role in p CNB degradation and approximately 98% of the initial p CNB (10 mg/L) was removed within 18 min. The degradation efficiency of p CNB was related to Zn(0) dosage and ozone flow amount, and the optimum conditions were 0.5 g/L and 4.8 mg/min, respectively. p CNB could be effectively degraded in the initial pH range of 4–10, but a higher or a lower pH was not beneficial to the removal of p CNB. Accompanying anions also affected p CNB degradation. Chloride and sulfate slightly improved p CNB degradation, whereas bicarbonate and phosphate markedly suppressed the degradation of p CNB. The reuse of Zn(0) (4 cycles) for p CNB ozonation indicated that the catalytic activity of Zn(0) maintained high and stable. The experiments of free radical scavengers ( tert -butyl alcohol and p -benzoquinone) corroborated the dominant active species responsible for p CNB degradation by a combination of ozone with Zn(0) was O 2 − rather than OH. Based on the results obtained in this study, it can be concluded that ozone activated by Zn(0) is an effective and promising approach to degrade organic contaminants.
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
Catalysts
·
2018
·Vol. 8
·期 5
·182
·
IF 3.465
Feng Li,Jinrong Liang,Wenxi Zhu,Hua Song,Keliang Wang,Cuiqin Li
Ni/TiO2catalysts with different morphologies (granular, sheet, tubular and spherical) were prepared. Hydrogen was generated from ethanol aqueous-phase reforming over Ni/TiO2in a water-ethanol-m-chloronitrobenzene reaction system and directly applied intom-chloronitrobenzene catalytic hydrogenation. Thereby, in-situ liquid-phase hydrogenation ofm-chloronitrobenzene over Ni/TiO2without addition of molecular hydrogen was successful. Compared with granular, sheet and spherical Ni/TiO2, the nanotubular Ni/TiO2prepared from one-step hydrothermal reaction had larger specific surface area, smaller and uniformly-distributed pore sizes and more Lewis acid sites. In-situ liquid-phase hydrogenation ofm-chloronitrobenzene experiments showed the nanotubular Ni/TiO2had the highest catalytic activity, which was ascribed to both catalyst morphology and acid sites. Firstly, the nanotubular structure endowed the catalysts with a nanoscale confinement effect and thereby high catalytic performance. Secondly, the Lewis acid sites not only accelerated water–gas shift reaction, enhancing the ethanol aqueous-phase reforming activity for hydrogen generation, but also promoted the adsorption and hydrogenation of –NO2on the active sites of the catalysts.Keywords:Ni/TiO2;morphology effect;in-situ hydrogenation;aqueous-phase reforming;m-chloronitrobenzene
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2017
·Vol. 5
·期 22
·11294-11300
·
IF 8.867
Xin Li,Yue Wang,Liqun Li,Wenqing Huang,Zicheng Xiao,Pingfan Wu,Wenbo Zhao,Wei Guo,Peng Jiang,Minghui Liang
Two types of model Pt–Cu catalysts are designed and prepared to explore the contribution of the geometric and electronic effects from copper to the catalytic performance of Pt nanoparticles in the selective hydrogenation of p-chloronitrobenzene (p-CNB). One model Pt–Cu catalyst (called Cu/C–Pt) is Pt nanoparticles deposited on ultra-small copper particle-decorated activated carbon, and the other is copper particle-decorated Pt/C catalyst (called Pt/C–Cu). Cu/C–Pt catalyst has an activity lower than that of Pt/C, but the selectivity of the desired product p-chloroaniline (p-CAN) on the Cu/C–Pt catalyst is much higher than that on Pt/C. On the Pt/C–Cu catalyst, p-CNB cannot be completely converted into p-CAN. The dechlorination rates of p-CAN on Cu/C–Pt catalysts are three orders of magnitude lower than that on Pt/C. More interestingly, the dechlorination reaction of p-CAN on Pt/C–Cu cannot be observed. High resolution TEM images of our Pt–Cu catalysts show that Pt nanoparticles keep their crystalline structure after incorporation with copper. The dispersions of Pt in 2Pt/C, 5Cu/C–2Pt, and 2Pt/C–5Cu reach 0.106, 0.083 and 0.027, respectively (the numbers before Pt and Cu represent their percentages), revealing that Pt nanoparticles in Cu/C–Pt have a larger exposed surface than those in Pt/C–Cu. It can be deduced that copper mainly exerts an electronic effect on the catalytic performance of Pt nanoparticles in Cu/C–Pt. On the other hand, the geometric effect on Pt from copper in Pt/C–Cu leads to not only a low dispersion of Pt nanoparticles but a weak activity in catalytic hydrogenation of p-CNB and dechlorination of p-CAN. The interaction between Pt nanoparticles and Cu nanoparticles at room temperature is also discussed.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2021
·
IF 7.92
Xiaohui Zhang,Qingqing Gu,Yanfu Ma,Qiaoqiao Guan,Rui Jin,Hengwei Wang,Bing Yang,Junling Lu
For supported metal catalysts, the underlying support not only disperses and stabilizes metal particles, but also modulates their electronic structures remarkably, and even directly participates in catalytic reactions. Here we report that Pd nanoparticles (NPs) supported on oxygen-functionalized carbon black (Pd/O-C) show an unexpected inverse trend of selectivity on Pd particle size in chemoselective hydrogenation of para -chloronitrobenzene ( p -CNB), compared to those on carbon black (Pd/C). In situ X-ray photoemission spectroscopy reveals that the Pd NPs are more positively charged with decrease of particle size in both samples, while the Pd NPs in Pd/O-C have relatively higher fractions of positive Pd δ+ species than those in Pd/C with similar sizes. Fourier transform infrared spectroscopy shows that the balance of positive Pd δ+ species strongly modulates the competitive adsorption of -NO 2 and -Cl group in p -CNB according to their different electronegativities. As a consequence, we, for the first time, demonstrate that a moderate positive charge of Pd NPs is essential to improve the p- chloroaniline ( p -CAN) selectivity, while too high or too low positive charge could impel the adsorption of the less negatively charged -Cl group, thus generating the dehalogenated aniline by-product. These findings suggest that precise tailoring of the electronic structures of metal NPs could be essential for design of high chemoselective metal catalysts.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
Scientific Reports
·
2025
·Vol. 15
·期 1
·1-11
·
IF 3.9
Wang Peng,Han Lifang,Zou Hua,Cao Yiyao,Gao Xiangjing,Ren Hong,Xu Qiuliang
We explored the feasibility of using urinary metabolites of p-chloronitrobenzene (p-CNB) as exposure biomarkers of occupational p-CNB exposure. Forty-two workers exposed to p-CNB during their jobs at a chemical enterprise in Shaoxing, Zhejiang Province, China were included in the exposure group, while administrative personnel who do not come into contact with p-CNB at work were included in the control group. Each worker in the exposure group was equipped with a personal air sampler to collect airborne p-CNB samples, and urine samples were collected at the conclusion of each shift. After sample collection, the airborne p-CNB concentrations and urinary metabolite concentrations were detected by gas chromatography-tandem mass spectrometry and ultra-performance liquid chromatography - quadrupole - orbitrap high resolution mass spectrometry, respectively. The urinary metabolite concentrations were corrected by the content of urinary creatinine. Subsequently, the correlations between the urinary metabolite concentrations and the p-CNB time-weighted average (TWA) concentrations were assessed using correlation analysis. All p-CNB TWA concentrations measured in this study were below the occupational exposure limit in the Chinese national standards. In the exposure group, N-acetyl-S-(4-nitrophenyl)-L-cysteine (NANPC), 2-chloro-5-nitrophenol (2C5NP), p-chloroacetanilide (p-CAA), p-chlorooxanilic acid (p-COA), 2-amino-5-chlorophenol (2A5CP), and p-chloroaniline (p-CA) were detected at varying levels. The percentages of NANPC, 2C5NP, p - CAA, p - COA, 2A5CP, and p - CA were 64.1%, 5.1%, 0.3%, 15.1%, 5.1%, and 10.3%, respectively. We found extremely significant positive relationships ( p < 0.01) between the urinary metabolite concentrations (p-CA, 2C5NP, 2A5CP, NANPC, and p-COA) and the p-CNB TWA concentrations, with respective correlation coefficients of 0.827, 0.673, 0.790, 0.714, and 0.741. Thus, these five metabolites may be used as exposure biomarkers of occupational p-CNB exposure. Moreover, among these metabolites, NANPC was identified as the most suitable exposure biomarker because it had the highest correlation coefficient and the highest content in urine.
研究领域:
职业卫生
·
毒理学
·
环境医学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2022
·
IF 4.326
Yebin Zhou,Ling Li,Yi Liu,Hongzheng Wang,Zhenlong Feng,Feng Feng,Qunfeng Zhang,Wucan Liu,Wenfeng Han,Chunshan Lu,Xiaonian Li
Most of the catalytic hydrogenation reactions take place under high temperature, high pressure, and high corrosion, which poses a challenge to the activity and stability of hydrogenation catalysts. Herein, an acid resistant and strawberry-like metal–carbon sphere (M/SCS) as a robust hydrogenation catalyst was synthesized by a one-step method. Self-assembled metal nanoparticles gather and are embedded on the surface of the carbon sphere prepared by the carbonization of phenolic resin. By means of the surrounding carbon layer, the acid resistant capability is orders of magnitude intensified compared to traditional commercial catalysts. Over 91.5% and 100% metals of Pd/SCS7 and Pt/SCS7 remain as the catalyst in hydrochloric acid (36–38 wt %), while less than 44.6% and 37.5% metals remain of commercial Pd/AC and Pt/AC. In addition, the sizes are controlled in the range of 11 to 18 nm for metal particles and 400 to 1600 nm for carbon spheres by adjusting the conditions of phenolic aldehyde condensation. N atoms anchored on the carbon spheres with high dispersion can improve electron density on metal particles. M/SCS exhibits both excellent stability and high catalytic performance in the hydrogenation reactions.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
WATER RESEARCH
·
2022
·
IF 13.4
Kai Wei,Yanyan Wan,Minzi Liao,Shiyu Cao,Hao Zhang,Xing Peng,Huayu Gu,Cancan Ling,Meiqi Li,Yanbiao Shi,Zhihui Ai,Jingming Gong,Lizhi Zhang
Chloronitrobenzenes (CNBs) are typical refractory aromatic pollutants. The reduction products of CNBs often possess higher toxicity, and the electron-withdrawing substituent groups are detrimental to the ring-opening during the oxidation treatment, leading to ineffective removal of CNBs by either reduction or oxidation technology. Herein we demonstrate a controllable reduction-oxidation coupling (ROC) process composed of zero-valent iron (ZVI) and H 2 O 2 for the effective removal of CNBs from both water and soil. In water, ZVI first reduced p-CNB into 4-chloronitrosobenzene and 4-chloroaniline intermediates, which were then suffered from the subsequent oxidative ring-opening by ·OH generated from the reaction between Fe(II) and H 2 O 2 . By controlling the addition time of H 2 O 2 , the final mineralization rate of p-CNB reached 6.6 × 10 −1 h −1 , about 74 times that of oxidation alone (9.0 × 10 −3 h −1 ). More importantly, this controllable ROC process was also applicable for the site remediation of CNBs contaminated soil by either ex-situ treatment or in-situ injection, and, respectively decreased the concentrations of p-CNB, m-CNB, and o-CNB from 1105, 980, and 94 mg/kg to 3, 1, and < 1mg/kg, meeting the remediation goals (p-CNB: < 32.35 mg/kg, o-CNB and m-CNB: < 1.98 mg/kg). These laboratory and field trial results reveal that this controllable ROC strategy is very promising for the treatment of electron-withdrawing groups substituted aromatic contaminates.
研究领域:
环境科学
·
污染治理
✓ 已验证
DOI
高影响因子
Toxics
·
2022
·Vol. 10
·期 6
·299
·
IF 4.472
Guoqiang Fan,Tianzhu Shen,Kun Jia,Xiaoping Xiao,Zhanfeng Wu,Fanghua Gong,Huiqiang Lu
Pentachloronitrobenzene (PCNB) is an organochlorine protective fungicide mainly used as a soil and seed fungicide. Currently, there are few reports on the toxicity of PCNB to zebrafish embryo. Here, we evaluated the toxicity of PCNB in aquatic vertebrates using a zebrafish model. Exposure of zebrafish embryos to PCNB at concentrations of 0.25 mg/L, 0.5 mg/L, and 0.75 mg/L from 6 hpf to 72 hpf resulted in abnormal embryonic development, including cardiac malformation, pericardial edema, decreased heart rate, decreased blood flow velocity, deposition at yolk sac, shortened body length, and increased distance between venous sinus and arterial bulb (SV-BA). The expression of genes related to cardiac development was disordered. However, due to the unstable embryo status in the 0.75 mg/L exposure concentration group, the effect of PCNB on the expression levels of cardiac-related genes was not concentration-dependent. We found that PCNB increased reactive oxygen species stress levels in zebrafish, increased malondialdehyde (MDA) content and catalase (CAT) activity, and decreased superoxide dismutase (SOD) activity. The increased level of oxidative stress reduced the proliferation ability of zebrafish cardiomyocytes, and the expressions of zebrafish proliferation-related genes such ascdk-2,cdk-6,ccnd1, andccne1were significantly down-regulated. Astaxanthin (AST) attenuates PCNB-induced reduction in zebrafish cardiomyocyte proliferation by reducing oxidative stress levels. Our study shows that PCNB can cause severe oxidative stress in zebrafish, thereby reducing the proliferative capacity of cardiomyocytes, resulting in zebrafish cardiotoxicity.Keywords:pentachloronitrobenzene;pericardial edema;reactive oxygen species;proliferation of cardiomyocytes;zebrafish
研究领域:
毒理学
·
水生生物学
·
心脏病学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
·
2019
·Vol. 19
·期 7
·3879-3886
·
IF 1.093
Liu Baoliang,Yang Bing,Sun Meiyu,Qian Xiangli,Zhang Qikun
In this study, a Pt loaded active carbon fiber (Pt/ACF) catalyst was prepared by immobilizing Pt nanoparticles on ACF. The catalyst accelerated hydrogenation of p-chloronitrobenzene (p-CNB) to p-chloroaniline (p-CA) at lower temperature and atmospheric pressure,
resulting in approximately 100% yield and selectivity. Several factors that affect p-CA yield were investigated. The nitro reduction rate reached 100% under the optimal reaction conditions, indicating excellent selectivity of the prepared catalyst. This process will overcome the environmental
pollution problems associated with the traditional process, and is a green synthetic process.
研究领域:
化学工程
·
环境科学
✓ 已验证
DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2018
·
IF 5.807
Linlin Chen,Junjie Shao,Hui Chen,Caiqin Wang,Xinyi Gao,Xiangyang Xu,Liang Zhu
For enhanced dechlorination of 2,4-dichloronitrobenzene (2,4-DClNB), a coupled microbial electrosynthesis-upflow anaerobic sludge reactor (MES-UASB) was established, and the effect of cathode potential on the performance of combined process was investigated in this study. Results showed that a higher dechlorination efficiency of 78.5 ± 6.1% was achieved in the coupled MES-UASB at −660 mV, and the degradation rate of 4-chloroaniline (4-ClAn) reached 4.61 mg·L −1 ·d −1 within 120 h at −660 mV of cathode potential in batch experiments. The results of Illumina sequencing indicated that the biocathode operated at a lower potential favored the enrichment of dechlorination-related microbes such as Dehalobacter , Dehalococcoides and Anaeromyxobacter both in granular sludge and cathode biofilm. It could be speculated that a lower cathode potential is more feasible for the dechlorination of 2,4-DClNB due to the enrichment of dechlorination-related microbes as well as the production of electrons with higher energy for long-distance electron transfer (LDET).
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
RSC Advances
·
2020
·Vol. 10
·期 33
·19247-19253
·
IF 3.119
Ying Han,Junkai Huang,Hongyuan Liu,Yue Wu,Zhao Wu,Kemin Zhang,Qingjie Lu
The reduction of p-chloronitrobenzene (p-CNB) by sulfate green rust (GRSO4) was systematically studied. The results revealed that GRSO4 has a good removal effect on p-CNB. The removal efficiencies of p-CNB by GRSO4 improved with the increase of the pH value. The removal efficiencies in the presence of ions were better than that of GRSO4 alone, while natural organic matter (NOM) could adsorb p-CNB, which competed with GRSO4. The reductions of p-CNB by GRSO4 under different conditions followed pseudo-first-order reaction kinetics except for the reactions in the presence of NOM. p-CNB was converted into p-chloroaniline (p-CAN), which produced p-nitrosochlorobenzene and p-chlorophenylhydroxylamine as the intermediate products. The results of the X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed GRSO4 was gradually transformed into goethite. Fe(II) in the GRSO4 structure was the main electron donor involved in the reaction.
研究领域:
环境科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2023
·
IF 7.5
Mengjiao Fan,Yuewen Shao,Kai Sun,Yuchen Jiang,Shu Zhang,Yi Wang,Song Hu,Jun Xiang,Xun Hu
Bio-oil as a carbon source can be used to prepare hybrid metal@carbon material while the polymerization of which generally prevents metals from exposure. In this study, melamine was used as a structural regulating agent for preparing Co/N/C catalyst via heating the mixture of cobalt nitrate, melamine and bio-oil for hydrogenation of o-chloronitrobenzene (o-CNB). The results showed that the Co species was encapsulated in the carbon structure from cross-polymerization of melamine and bio-oil at 600 °C. The further heating to 900 °C led to decomposition of melamine-derived substance, and meanwhile cobalt oxide was reduced and confined in the resulting carbon structure. The formed metallic Co catalyzed the growth of long carbon nanotube with cobalt on the tip, forming the Co/N/C catalyst of higher specific surface area (128.2 m 2 /g) and metallic Co dispersion (3.7%), rendering the superior activity for hydrogenation of o-CNB with the yield of o-chloroaniline up to 90.2%. The encapsulation or exposure of Co species was closely related to relative ratio of bio-oil and melamine in the catalyst precursors. Additionally, leaching of cobalt, due to dechlorination of o-CNB, was found to be an issue of Co/N/C catalyst but not for that of Ni/N/C catalyst.
研究领域:
催化化学
·
能源材料科学
✓ 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）