GREEN CHEMISTRY
·
2018
·Vol. 20
·期 21
·4946-4956
·
IF 8.586
Yongshen Ren,Ziliang Yuan,Kangle Lv,Jie Sun,Zehui Zhang,Quan Chi
The development of new strategies for metal-free promoted reactions has recently received great interest from chemists because these processes benefit from the use of inexpensive catalysts and from avoidance of contamination of the desired products by the metal catalysts. In this study, a method for HNO3-promoted oxidation of biomass-derived 5-hydroxymethylfurfural (HMF) to 2,5-diformylfuran (DFF) was developed in the presence of nitrogen-doped carbon materials using molecular oxygen as the terminal oxidant under mild reaction conditions. The catalytic activity of the nitrogen-doped carbon materials was discovered to greatly increase with increasing pyrolysis temperature; it also depended on both the type of nitrogen atoms in the catalyst and the surface area of the catalyst. The NC-950 catalyst demonstrated unprecedented catalytic activity towards the oxidation of HMF to DFF. Several reaction parameters, such as the reaction solvent, the reaction temperature, the amount of HNO3, the catalyst loading and the oxygen pressure, have been investigated. The highest DFF yield of 95.1% was attained with full HMF conversion after 14 h at 100 °C under 10 bar oxygen pressure in the presence of a catalytic amount of HNO3. Control experiments indicated that the oxidation of HMF was initially promoted by HNO3, and O2 acted as a secondary oxidant for HNO3 recovery. In particular, the NC-950 catalyst had remarkable reusability without significant losses in its activity and selectivity after six consecutive usages.
研究领域:
化学工程
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生物质转化
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2014
·Vol. 6
·期 7
·3753-3763
·
IF 6.739
Lun Li,Liguang Dou,Hui Zhang
M3Al-layered double hydroxide (LDH, M = Mg, Ni, Co) supported Au nanoclusters (AuNCs) catalysts have been prepared for the first time by using water-soluble glutathione-capped Au nanoclusters as precursor. Detailed characterizations show that the ultrafine Au nanoclusters (ca. 1.5 ± 0.6 nm) were well dispersed on the surface of LDH with a loading of Au below ∼0.23 wt% upon synergetic interaction between AuNCs and M3Al-LDH. AuNCs/Mg3Al-LDH-0.23 exhibits much higher catalytic performance for the oxidation of 1-phenylethanol in toluene than Au/Mg3Al-LDH(DP) by the conventional deposition precipitation method and can be applied for a wide range of alcohols without basic additives. This catalyst can also be reused without loss of activity or selectivity. The AuNCs/M(= Ni, Co)3Al-LDH catalysts present even higher alcohol oxidation activity than AuNCs/Mg3Al-LDH. Particularly, AuNCs/Ni3Al-LDH-0.22 exhibits the highest activity (46 500 h−1) for the aerobic oxidation of 1-phenylethanol under solvent-free conditions attributed to its strongest Au–support synergy. The excellent activity and stability of AuNCs/M3Al-LDH catalysts render these materials promising candidates for green base-free selective oxidation of alcohols by molecular oxygen.
研究领域:
化学
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催化科学
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材料科学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2023
·
IF 9.9
Jiaqi Hu,Fangyuan Chen,Jie Mao,Linjie Ni,Jinfeng Lu
Molecular oxygen activation is essential to the photocatalytic oxidation reaction, which is highly dependent on the construction of active sites and efficient charge transfer of photocatalysts. In this study, we constructed Bi 4 V 2 O 11 /Ag/AgCl Z-type heterojunction photocatalysts with significantly enhanced molecular oxygen activation capacity. The systematic characterization and analysis including X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations confirmed that the formation of efficient Z-type heterostructure could be attributed to the introduction of Ag nanoparticles (NPs), which regulated the electron transfer direction from Bi 4 V 2 O 11 to AgCl. Owing to the advantage of enhanced charge transfer efficiency, the O 2 − generation capacity of Bi 4 V 2 O11/Ag/AgCl Z-scheme heterojunction was as high as 4.6 times that of pure Bi 4 V 2 O 11 . Consequently, Bi 4 V 2 O 11 /Ag/AgCl showed good degradation performance against tetracycline (TC), ciprofloxacin (CIP), ranitidine hydrochloride (RAN) and 2,4-dichlorophenoxyacetic acid (2,4-D) under visible light, and their degradation rates were 8.2 times, 5.9 times, 3.8 times and 11.9 times higher than those of Bi 4 V 2 O 11 , respectively. This study provides an effective and feasible strategy to design photocatalyst with improved molecular oxygen activation efficiency.
研究领域:
环境科学
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材料科学
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化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials Today Sustainability
·
2023
·
IF 7.8
G. Yang,H. Sun,R. Liu,J. Shi,X. Tong
Heterogeneous catalytic and selective C–C bond cleavage is considered as the important way for the production of high valuable compounds from large-molecule-weight feedstock . In this article, a sustainable and efficient aerobic oxidative C–C bond cleavage of lignin models is developed with the bismuth-based solid catalyst. Therein, the flower-like Bi 2 O 2 CO 3 exhibits a high photocatalytic efficiency in the reaction medium combined of n-butanol and tetramethylammonium bromide. For example, the selective oxidative C–C bond cleavage of 1-phenyl-ethane-1, 2-diol has been successfully carried out, where the substrate conversion and the selectivity of benzaldehyde was 95% and 99%, respectively. The study exhibited that the amount of oxygen vacancies plays a significant role on the photocatalytic selective aerobic oxidative cleavage processes. Moreover, the selective aerobic oxidative C–C bond cleavage of different lignin models was investigated, and all the yields of corresponding products are more than 90% with this photocatalytic system. Furthermore, the used flower-like Bi 2 O 2 CO 3 can be recycled at least 5 times without the obvious decrease of catalytic activity .
研究领域:
催化化学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Reaction Kinetics Mechanisms and Catalysis
·
2013
·Vol. 111
·期 2
·535-547
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IF 1.104
Chen Shichang,Lu Wangyang,Yao Yuyuan,Chen Haixiang,Chen Wenxing
Iron tetranitrophthalocyanine (FePc) was modified and immobilized on carbon fiber (FePc(NO 2 ) 3 –CF) by covalent bond to obtain a supported heterogeneous catalyst for the removal of dibenzothiophene (DBT) in tridecane. In the supported catalytic system, the catalyst exhibited an excellent catalytic performance without any sacrificial agents, and the conversion of DBT could reach 92 % at 130 °C and 0.2 MPa of initial dioxygen pressure for 3 h. Compared to unsupported FePc, the introduction of carbon fiber dramatically improved the catalytic activity of FePc and facilitated the reuse of catalysts. The amount of FePc(NO 2 ) 3 –CF, temperature and the initial pressure of molecular oxygen were also studied in detail to optimize the reaction conditions. The removal of DBT significantly increased with the increasing of concentration of DBT in model oil. Finally, a mechanism involving high-valent iron oxo species was proposed for the oxygenation. This study provides new insights into industrial desulfurization systems using carbon fiber as catalyst carrier.
研究领域:
化学工程
·
环境科学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Qin Ma,Yukun Cui,Jun Sun,Yuqing Li,Jialu Li,Sihui Zhan,Wenping Hu,Yi Li
Tetrathiafulvalene (TTF), one of the well-known organic photoelectric materials, was served as active sites to accelerate the activation of molecular oxygen to degrade organic pollutants. Herein, a kind of Z-scheme heterojunction photocatalysis was constructed based on g-C 3 N 4 and TTF. According to the experimental results, the mechanism of Z-scheme heterojunction was supported, in which photogenerated electrons transferred from g-C 3 N 4 to TTF. More importantly, TTF on the catalyst surface could serve not only as electron donor, but also as the terminal active site to transfer photoexcited electrons to adsorbed oxygen molecules, producing mass of ⋅O 2 – . Meanwhile, the activation rate constant of TCN-5 for RhB was 0.0624 min −1 , which was 10 and 5 times of g-C 3 N 4 and TTF, respectively. In addition, the results of EPR spectra, rotating disk electrode measurement and molecular oxygen activation measurement also demonstrated that this catalyst was energetically favorable to generate ⋅O 2 – through the single-electron reduction pathway of molecular oxygen. Finally, four possible photodegradation routes for RhB were proposed based on the results of HPLC-MS. This work provides a new insight on the application of organic photoelectric materials in the purification of wastewater by the molecular oxygen activation.
研究领域:
环境科学
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材料科学
·
有机化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Yanjing Liu,Ruitao Wang,Shuhong Liu,Yunsong Xu,Zhirong Zhang,Ying Song,Zhongping Yao
The Fenton-like activated molecular oxygen technology demonstrates significant potential in the treatment of refractory organic pollutants in wastewater, offering promising development prospects. We prepared a N -doped C -coated copper-based catalyst Cu 0 /NC3-600 through the pyrolysis of Mel-modified Cu-based metal–organic framework (MOF). The results indicate that the degradation of 20 mg/L norfloxacin (NOR) was achieved using 1.0 g/L Cu 0 /NC3-600 across a wide pH range, with a removal rate exceeding 95 % and total organic carbon (TOC) removals approaching 70 % after 60 min at pH 5–11. The nitrogen doping enhances the electronic structure of the carbon material, facilitating the adsorption of molecular oxygen. Additionally, the formed carbon layer effectively prevent copper leaching,contributing to increased stability to a certain extent. Subsequently, we propose the catalytic reaction mechanism for the Cu 0 /NC/air system. Under acidic conditions, Cu 0 /NC3-600 activates molecular oxygen to produce the •O 2 – , which serves as the primary active species for NOR degradation. While in alkaline conditions, the high-valent copper species Cu 3+ is generated in conjunction with •O 2 – , both working simultaneously for NOR degradation. Furthermore, based on the LC-MS results, we deduced four possible degradation pathways. This work offers a novel perspective on expanding the pH range of copper-based catalysts with excellent ability to activate molecular oxygen for environmental water treatment.
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
NEW JOURNAL OF CHEMISTRY
·
2020
·Vol. 44
·期 16
·6251-6260
·
IF 3.288
Chaowei Wang,Zhe Liu,Ruimin Gao,Jinhua Liu,Siying An,Ronglan Zhang,Jianshe Zhao
Novel composite materials of vanadium-substituted Keggin-type polyoxometalates anchored on amine-functionalized Ce-MCM-41 (POM/APTES-CeM) are successfully synthesized and fully characterized by FT-IR, XRD, N2 adsorption–desorption isotherms, SEM, TEM, EDX, and XPS. The catalytic activities of these new catalysts are evaluated for the oxidative desulfurization of the model fuel with molecular oxygen as an oxidant. Meanwhile, the optimal reaction conditions are investigated, including the loading amount of POM, catalyst mass, reaction temperature, agitation rate and the amount of oxygen. This result shows that PW9V3/APTES-CeM-50 exhibits the highest catalytic activity with a desulfurization performance of 99.26% as well as brilliant reusability and catalytic efficiency with slight diminution after being used consecutively eight times. Moreover, the kinetic study displays that the oxidative desulfurization process conforms to the pseudo-first-order model.
研究领域:
化学工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED ORGANOMETALLIC CHEMISTRY
·
2016
·Vol. 31
·期 3
·e3578
·
IF 2.452
Yongjin Li,Baoshuai Sun,Yuanrong Zhou,Weijun Yang
A porous alkynylporphyrin conjugated organic polymer (MnE-TPP) was synthesized by Sonogashira coupling reaction with Mn(II) 5,10,15,20-tetrakis(4′-ethynylphenyl)porphyrin and Mn(II) 5,10,15,20-tetrakis(4′-bromophenyl)porphyrin as building blocks. The polymer was characterized using nitrogen adsorption–desorption isotherms, field-emission scanning electron microscopy, high-resolution transmission electron microscopy, Fourier transform infrared and UV–visible spectroscopies, X-ray diffraction, thermogravimetry and inductively coupled plasma atomic emission spectrometry. The electrochemical behaviors of MnE-TPP were investigated by cyclic voltammetry. MnE-TPP was developed as a heterogeneous catalyst for the activation of molecular oxygen to oxidize toluene under mild conditions. The selectivity of total benzaldehyde and benzyl alcohol remained above 70.0% with a conversion of toluene up to 10.2%. The turnover number was as high as 13 653. Also, MnE-TPP remained structurally stable and the toluene conversion rate hardly decreased after 5 h of reaction and five cycles of reuse.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2016
·
IF 3.611
Si-Wen Li,Rui-Min Gao,Rong-Lan Zhang,Jian-she Zhao
A catalyst system designed by a kind of hybrid material POM@MOF-199@MCM-41 (PMM) was found by a one pot and POM template self-construction of MOF-199 in the pore of MCM-41. This catalyst was exploited to act as a stable heteropolyacid-based one in the direct oxidative desulfurization process with a feedstock of model oil under O 2 as oxidant. Based on optimal conditions, the DBT conversion reached up to 98.5% and the PMM could be recycled ten times with a slight decrease, which was compared with heteropolyacid only based on MOF-199 and MCM-41, respectively. Additionally, the structure of ordered nano-sized pores of MOF-199 with POM encapsulated in was clear under crystal analysis, which offered strong evidences for the further movement into the MCM-41.
研究领域:
化学
·
催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Zhao Yang,Yong Liu,Jianlong Wang
Zero-valent copper (ZVC) has shown potential as an oxygen activator for the degradation of organic pollutants from aqueous solution. Nevertheless, the high leaching of copper ions and the demand for acidic condition limited its application. In this study, a novel mesoporous carbon hybrid loaded zero-valent copper (Cu 0 /C) was successfully synthesized from Cu-based metal–organic framework (Cu 3 (BTC) 2 ) through a pyrolysis method and applied to efficiently degrade sulfamethazine (SMT) at neutral pH under aeration condition. The performance of Cu 0 /C composite for the activation of molecular oxygen was evaluated based on the effect of different reaction parameters, such as, initial SMT concentration, initial pH, activator dosage and reaction temperature. The results showed a high efficiency for SMT removal over a broad pH range (3.0–7.0). Moreover, the Cu 0 /C composite exhibited excellent stability and reusability for SMT degradation, and a 96.7% SMT removal and a 68.8% total organic carbon (TOC) conversion were achieved at pH 5.8 after continuous three cycles. Combined with the determination results of reactive oxidizing species and physical-chemical characterization, cupryl species (Cu 3+ ) rather than OH produced by the reaction of the in-situ generated H 2 O 2 with Cu + were the major reactive species. Additionally, the possible reaction mechanism of Cu 0 /C activated oxygen was tentatively proposed.
研究领域:
环境科学
·
材料化学
✓ 已验证
DOI
高影响因子
Canadian Journal of Chemistry
·
2018
·Vol. 96
·期 8
·
IF 1.084
Yongshu Li,Nizhou Xu,Guangyao Mei,Yun Zhao,Yiyong Zhao,Jinghui Lyu,Guofu Zhang,Chengrong Ding
A mild, simple process for the effective aerobic oxidative deoximation of a wide range of ketoximes and aldoximes has been developed that utilizes Fe(NO3)3·9H2O as the single catalyst and molecular oxygen as the green oxidant. The environmentally benign protocol provides moderate to excellent yield and broad functional groups tolerance and is a valuable synthetic method for practical applications. According the relevant verification experiment, a plausible mechanism has been proposed.
研究领域:
有机化学
·
绿色化学
✓ 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）