CHEMICAL ENGINEERING JOURNAL
·
2015
·
IF 4.321
Yanmei Yuan,Hong Tao,Jinhong Fan,Luming Ma
Compared with heavy metal catalysts, persulfate (PS) activated with iron-based materials for controlling refractory organic pollutants are more effective, environment-friendly, and safe to human health. However, Fe 2+ application is limited to acidic conditions, and Fe 0 is not thermodynamically stable in water. Ferrous sulfide (FeS) ore particles are large-sized, low-purity, crystallized iron-based materials that are inexpensive and readily available. In this work, FeS is proposed as an alternative electron donor to activate persulfate and degrade p -chloroaniline (PCA). The effects of initial solution pH, FeS dose, and persulfate concentration on PCA degradation and total organic carbon (TOC) removal were examined at 20 ± 5 °C in batch experiments. Cl − , SO 4 2 − , and Fe 3+ ions were the main inorganic products used to investigate the oxidative mechanism in the present system. Compared with Fe 2+ , FeS could serve as a continuous-releasing source of dissolved Fe 2+ and surface bound Fe 2+ , with PCA removal increasing by 80% at pH 7.0 for a 1 h reaction. In contrast with Fe 0 , recycling of Fe 3+ to Fe 2+ can prevent excessive Fe 2+ consumption and Fe 3+ accumulation. The PS activation mechanism was affected by the initial solution pH. And the application ranges of pH for PCA fast degradation was from 3.0 to 7.0 in the tested pH values of 3.0–11.0 and nearly complete degradation of PCA (>99%) was observed at 150 min, PCA degradation increased as the FeS dose and persulfate concentration increased. PCA removal, dechlorination, and TOC removal reached over 99% within 60, 210, and 500 min, respectively. Generation of small amounts of amorphous iron oxide precipitants on the residual FeS surface was, observed and FeS recyclability was conducted preliminarily. These findings suggest that FeS can function as an effective persulfate activator for PCA control.
研究领域:
环境科学
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化学工程
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Chenhui Yao,Yongqing Zhang,Meimei Du,Xiaodong Du,Shaobin Huang
Persistent organic pollutants (POPs) are widely distributed and have significant negative environmental impacts. Advanced oxidation processes (AOPs) based on sulfate radicals produced from persulfate (PS) have attracted considerable attention for the degradation of POPs, however, there are several disadvantages with these radical activation systems. This study examined the degradation of p -chloroaniline (PCA) by persulfate (PS) activated with activated carbon (AC). The effects of initial pH and dosage of AC were also investigated. Results showed that AC exhibits good catalytic activity toward PS. Increasing AC dosage significantly improved the PCA degradation rate but PCA removal was not obviously influenced by initial pH ranging from 3 to 9. PS activation in the PS/AC system was a non-radical process as demonstrated by (i) ethanol and tert -butyl alcohol having little effect on PCA removal and (ii) Electron Paramagnetic Resonance results showing no radicals signals in the PS/AC system. Results also demonstrated that TOC could be removed in PS oxidation and PCA dechlorination was rapid (in the initial 30 min). The three major intermediates identified during the PCA degradation in the non-radical oxidation process were N-(4-chloro-phenyl)-benzene-1,4-diamine, 4-chloro-phenyl-diazene and hydroquinone and two pathways of PCA degradation was proposed. This study proposes a new insights into the mechanism of PS activation by AC and an efficient method for POPs removal.
研究领域:
环境科学
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化学工程
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2016
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IF 5.31
Yongqing Zhang,Hien Phuong Tran,Xiaodong Du,Imtyaz Hussain,Shaobin Huang,Shaoqi Zhou,William Wen
In recent years, persulfate activation systems have received increasing attention due to their high oxidation reactivity when removing environmental pollutants. Pyrite, the most common metal sulfide on Earth’s surface, can supply abundant Fe 2+ for persulfate activation. The role of the generated reactive oxygen species (ROS) in persulfate-pyrite systems however, is not fully understood. In this study, batch experiments were used to investigate p -chloroaniline (PCA) degradation by a pyrite-persulfate system. The effects of pyrite dosage, pH, temperature, air conditions (aerobic vs. anaerobic) and pyrite particle size on PCA degradation were examined. Radical detection was conducted using electron paramagnetic resonance (EPR) methods. Results from the EPR spectra indicated that PCA degradation was achieved by sulfate radical and hydroxyl radical oxidation. Aerobic conditions were more beneficial to PCA degradation than anaerobic conditions due to the generated superoxide radicals (O 2 − ) that activated the persulfate to produce more sulfate radicals (SO 4 − ). PCA degradation also increased with higher pyrite doses and under acidic conditions (pH 3.0 and 5.0). PCA was removed completely at pH 3.0 after 60 min. Temperature increase from 10 to 50 °C significantly promoted PCA degradation. These findings provide new understanding of the mechanism involved in pyrite activation of persulfate which can be used to improve PCA degradation by pyrite-persulfate systems.
研究领域:
环境科学
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化学
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DOI
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 23
·11788-11793
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IF 3.708
Yanyan Fang,Hailian Xiao,Ning Sui,Manhong Liu,William W. Yu
Supported Pt nanocatalysts with controlled particle size and size distribution were prepared by immobilizing Pt colloids on different iron oxide supports (γ-Fe2O3, Fe3O4, Fe2O3) via physical adsorption. These catalysts were used to catalyze the liquid phase hydrogenation of o-chloronitrobenzene (o-CNB) to o-chloroaniline (o-CAN) under mild reaction conditions (298 K, 0.1 MPa). The Pt/γ-Fe2O3 exhibited higher catalytic selectivity and activity than other similar works (selectivity = 99.9%, activity = 0.20 molo-CNB/(molPt s)). The stability of the Pt/γ-Fe2O3 was investigated, and the result showed that higher drying temperature could increase the stability of the catalyst.
研究领域:
化学工程
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催化材料科学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2017
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IF 6.216
Jinhong Fan,Lin Gu,Deli Wu,Zhigang Liu
Among the numerous iron-based materials for persulfate (PS) activation, mackinawite (FeS) particles have gained considerable interest as a ubiquitous natural mineral due to their high reactivity. However, the iron and sulfur co-mediated reaction mechanism of PS activation by FeS remains ambiguous. In this study, FeS was applied as a catalyst to activate PS for p -chloroaniline (PCA) degradation and mineralization over a wide initial pH range (3.0–11.0). The reaction was found to follow pseudo-first-order kinetics, with rate constants ranging from 0.0044 to 0.0144 min −1 . The reaction mechanism was elucidated by electron spin resonance (ESR) and quenching studies. A heterogeneous activation mechanism, in which surface Fe(II) species activated PS to produce OH ads and SO 4 − ads , controlled by surface reaction and diffusion was proposed, whereas OH free and SO 4 − free diffusing from the FeS surface were mainly responsible for PCA degradation. The sulfur-mediated cycling of iron species was investigated by comparing PS activation by zero-valent iron (ZVI) and FeS, exogenous Fe(III) addition and X-ray photoelectron spectroscopy (XPS). The results suggested that Fe(II) and S(-II) experienced independent oxidations and that S(-II) species could regenerate Fe(II) from Fe(III) at the FeS surface. Therefore, the S(-II)-promoted Fe(II)/Fe(III) cycle resulted in less PS decomposition but a higher PCA mineralization efficiency. The findings of this study elucidated the novel surface activation mechanism of PS by FeS and provided useful information for utilizing FeS to remediate contaminated water.
研究领域:
环境科学
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化学工程
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DOI
高影响因子
BIORESOURCE TECHNOLOGY
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2018
·
IF 5.807
Hao Xu,Xuesong Zhao,Shaobin Huang,Han Li,Na Tong,Xiangyu Wen,Congcong Sun,Saima Fazal,Yongqing Zhang
This study aimed to illustrate p -Chloroaniline ( p -CIA) biodegradation efficiencies in bioelectrochemical reactors under stimulation by a low-voltage electric field (0.2 V versus Ag/AgCl) in the presence of easily-degrading cosubstrates including glucose and acetate. The biodegradation efficiencies of closed-circuit bioreactors were compared with those of open-circuit reactors. Experimental results showed that the six different bioreactors provided different p -CIA biodegradation efficiencies. The highest biodegradation efficiency of 38.5 ± 10.3 mg/l was obtained in a closed-circuit bioreactor with acetate and the lowest biodegradation efficiency of 15.7 ± 9.4 mg/l was obtained in an open-circuit bioreactor. This difference may be attributed to the presence of electrical stimulation and acetate. The results for generated current and biodegradation efficiency indicated that acetate is a better cosubstrate than glucose. High-throughput sequencing technologies were used to characterise the bacterial community structure of the six bioreactors and revealed that different bacterial communities resulted in different treatment efficiencies.
研究领域:
环境工程
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微生物学
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生物技术
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产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
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2018
·
IF 6.653
Junjian Zheng,Zhiwei Wang,Jinxing Ma,Shaoping Xu,Zhichao Wu
Inability to remove low-molecular-weight anthropogenic contaminants is a critical issue in low-pressure membrane filtration processes for water treatment. In this work, a novel electrochemical ceramic membrane filtration (ECMF) system using TiO2@SnO2–Sb anode was developed for removing persistent p-chloroaniline (PCA). Results showed that the ECMF system achieved efficient removal of PCA from contaminated waters. At a charging voltage of 3 V, the PCA removal rate of TiO2@SnO2–Sb ECMF system under flow-through mode was 2.4 times that of flow-by mode. The energy consumption for 50% of PCA removal for TiO2@SnO2–Sb ECMF at 3 V under flow-through mode was 0.38 Wh/L, much lower than that of flow-by operation (1.5 Wh/L), which was attributed to the improved utilization of the surface adsorbed HO· and dissociated HO· driven by the enhanced mass transfer of PCA toward the anode surface. Benefiting from the increased production of reactive oxygen species such as O2•–, H2O2, and HO· arising from excitation of anatase TiO2, TiO2@SnO2–Sb ECMF exhibited a superior electrocatalytic activity to the SnO2–Sb ECMF system. The degradation pathways of PCA initiated by OH· attack were further proposed, with the biodegradable short-chain carboxylic acids (mainly formic, acetic, and oxalic acids) identified as the dominant oxidized products. These results highlight the potential of the ECMF system for cost-effective water purification.
研究领域:
环境工程
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水处理
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电化学
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膜技术
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2024
·
IF 12.2
Changjin Ou,Sujuan Yuan,Fujii Manabu,Ke Shi,Mohamed Elsamadony,Juntong Zhang,Juan Qin,Jian Shi,Zhipeng Liao
Anaerobic biotechnology for wastewaters treatment can nowadays be considered as state of the art methods. Nonetheless, this technology exhibits certain inherent limitations when employed for industrial wastewater treatment, encompassing elevated substrate consumption, diminished electron transfer efficiency, and compromised system stability. To address the above issues, increasing interest is being given to the potential of using conductive non-biological materials, e,g., iron sulfide (FeS), as a readily accessible electron donor and electron shuttle in the biological decontamination process. In this study, Mackinawite nanoparticles (FeS NPs) were studied for their ability to serve as electron donors for p -chloronitrobenzene ( p -CNB) anaerobic reduction within a coupled system. This coupled system achieved an impressive p -CNB removal efficiency of 78.3 ± 2.9% at a FeS NPs dosage of 1 mg/L, surpassing the efficiencies of 62.1 ± 1.5% of abiotic and 30.6 ± 1.6% of biotic control systems, respectively. Notably, the coupled system exhibited exclusive formation of aniline (AN), indicating the partial dechlorination of p -CNB. The improvements observed in the coupled system were attributed to the increased activity in the electron transport system (ETS), which enhanced the sludge conductivity and nitroaromatic reductases activity. The analysis of equivalent electron donors confirmed that the S 2- ions dominated the anaerobic reduction of p -CNB in the coupled system. However, the anaerobic reduction of p -CNB would be adversely inhibited when the FeS NPs dosage exceeded 5 g/L. In a continuous operation, the p -CNB concentration and HRT were optimized as 125 mg/L and 40 h, respectively, resulting in an outstanding p -CNB removal efficiency exceeding 94.0% after 160 days. During the anaerobic reduction process, as contributed by the predominant bacterium of Thiobacillus with a 6.6% relative abundance, a mass of p -chloroaniline ( p -CAN) and AN were generated. Additionally, Desulfomonile was emerged with abundances ranging from 0.3 to 0.7%, which was also beneficial for the reduction of p -CNB to AN. The long-term stable performance of the coupled system highlighted that anaerobic technology mediated by FeS NPs has a promising potential for the treatment of wastewater containing chlorinated nitroaromatic compounds, especially without the aid of organic co-substrates.
研究领域:
环境工程
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生物技术
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废水处理
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化学工程
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微生物学
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产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2022
·
IF 9.136
Minjun Liu,Ying Liu,Xinru Liu,Chengcheng Chu,Ducheng Yao,Shun Mao
Metal organic framework (MOF)-derived materials normally have three-dimensional (3D) structure, while little attention has been paid to two-dimensional (2D) MOF-derived materials with high catalytic activity. Nevertheless, the underlying agglomeration and metal leaching issues of 2D MOF-derived catalysts hinder their real applications. In this work, we report a bimetallic nanocomposite (Ni-Fe-C-600-acid/GO) derived from 2D Ni-Fe-MOF and graphene oxide (GO) network. Employing Ni(0) and Fe 3 O 4 as active site, the Ni-Fe-C-600-acid/GO shows high efficiency in peroxydisulfate (PDS) activation for the removal of p-chloroaniline (PCA), and the catalyst/PCA dosage ratio (0.8) is substantially lower than those of the previous studies (3.9–156.9). The prepared catalysts demonstrate high catalytic activity over a wide pH range of 3–9 and maintain high efficiency after five cycles with good tolerance to inorganic anions. The singlet oxygen is identified as the predominant active species and relatively weak contributions from sulfate free radicals and hydroxyl radicals are confirmed. This catalysis system presents new insights in 2D MOF-derived catalysts in advanced oxidation processes .
研究领域:
材料科学
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环境工程
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催化
·
纳米技术
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
·
IF 13.3
Zhengkai Wu,Yunning Chen,Xueying Cheng,Renquan Guan,Shuyu Chen,Yingna Guo,Qingkun Shang
How to design and optimize the single-molecule structure of perylene diimide derivatives (PDIs) to obtain high-performance photocatalysts is one of the challenges facing the current research field of PDIs photocatalysis. In this article, we regulate the π-π self-assembly stacking and optoelectronic properties of PDIs by changing the type and position of substituents on the amide site. The PDI-PBA photocatalyst with excellent performance was obtained from seven types of PDIs supramolecular materials. Theoretical calculations and optoelectronic performance tests have shown that PDI-PBA has good crystallinity and maximum dipole moment, resulting in its maximum built-in electric field, effectively promoting the separation and transport of photo-generated carriers. The transient absorption spectra further indicate that photogenerated electrons and holes of PDI-PBA have outstanding separation efficiency and ultra-long lifetime. In the batch reactor, PDI-PBA can degrade almost 100% acetaminophen within 60 min. In the dynamic cycling system with a surface hydraulic load of 14.56 L/(m 2 ·h), the efficiency of PDI-PBA photocatalytic degradation of acetaminophen can reach 84%. PDI-PBA can also effectively degrade phenol, levofloxacin, and ciprofloxacin. This work provides a successful example for the design of novel and efficient PDIs supramolecular materials, and lays the foundation for the application of PDIs photocatalysts in practical wastewater treatment.
研究领域:
材料科学
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环境科学
·
化学
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产品关联
DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2024
·
IF 3.8
Yali Yang,Jia Chen,Xiaojing Liang,Bei Liu,Kaijun Quan,Xiuhui Liu,Hongdeng Qiu
In this paper, three imidazole- and C18- bifunctional silica stationary phases (Sil-Im-C18) were prepared by adjusting introduction interval of octadecyltrichlorosilane (ODS) and 3-imidazol-1-ylpropyl(trimethoxy)silane (TMPImS), which can be used for reversed-phase liquid chromatography (RPLC) and ion exchange chromatography (IEC) with adjustable performance. The successful preparation of Sil-Im-C18 were confirmed by the characterizations of elemental analysis, infrared spectroscopy (FTIR) and contact angle (CA). Chromatographic performance of Sil-Im-C18 were evaluated by the separation of Tanaka test mixture, alkylbenzenes, linear PAHs and a set of analytes with different properties (uracil, phenol, 1,2-dinitrobenzene and naphthalene), and compared with commonly used C18 column. It was found that the chromatographic performance of Sil-Im-C18 changed significantly with the difference in bonding amount of imidazole and C18. Sil-Im-C18 demonstrated the excellent separation performance towards polycyclic aromatic hydrocarbons (PAHs), phenylesters, phenylamines , phenols and inorganic anions, and notably, nucleobases and nucleosides can be separated using pure water as mobile phases . The van Deemter plot showed that the column efficiency of Sil-Im-C18-3 was 64,933 plate· m − 1 for naphthalene, indicated that Sil-Im-C18 was reasonably chromatographic columns. The RSD values of retention time were 0.22 %-0.61 % for 10 needles alkylbenzenes injected continuously at 50 °C to investigate thermal stability and repeatability, all the fluctuations of k of naphthalene were less than 2.3 % for Sil-Im-C18-1 during flushing 24 h with the mobile phase at different pH values (pH = 3 and 8), the retention time of alkylbenzenes were almost same for Sil-Im-C18-1 at different time, the RSD values of retention time of alkylbenzenes were 0.45 %-2.28 % for two batches Sil-Im-C18-1, revealing the excellent repeatability, thermal stability, durability and reproducibility of Sil-Im-C18, and implying a commercial prospect.
研究领域:
分析化学
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色谱技术
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产品关联
DOI
PubMed
高影响因子
Catalysts
·
2024
·Vol. 14
·期 10
·724
·
IF 3.8
Nannan Zhan,Yan Xiao,Xingkun Chen,Yuan Tan,Yunjie Ding
In this study, carbon materials with different dimensions, including the typical one-dimensional (1D) carbon nanotube (CNT), two-dimensional (2D) graphene (GF), and three-dimensional (3D) activated carbon (AC), were investigated as a support for Pt catalysts for the selective hydrogenation of 3,4-dichloronitrobenzene (3,4-DCNB) to 3,4-dichloroaniline (3,4-DCAN). Notably, the Pt/CNT catalyst with the lowest dimension exhibited the best conversion of 3,4-DCNB under mild reaction conditions, followed by Pt/GF. Comprehensive characterizations, including XRD, TEM, XPS, and in situ CO DRIFTS, reveal that the dimension of carbon supports plays an important role in the particle size and electronic properties of Pt species, consequently affecting the catalytic performances of Pt catalysts. According to the results, electron-deficient Pt particles with small sizes are more favorable for the hydrogenation of 3,4-DCNB to 3,4-DCAN. In addition, dynamic tests and in situ DRIFTS of 3,4-DCNB indicated that the carbonaceous supports will largely influence the adsorption and activation capacity of the Pt catalysts, so that Pt loaded on CNT and GF are superior to that on the AC. We believe this study will provide good guidance for designing efficient carbon-supported metal catalysts for selective hydrogenation.
研究领域:
化学工程
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催化科学
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材料科学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）