Molecular Catalysis
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2022
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IF 5.089
Jiacheng Xu,Tiantian Zhang,Shiyu Fang,Zuliang Wu,Erhao Gao,Jiali Zhu,Shuiliang Yao,Jing Li,Lianxin Dai,Weihua Liu,Buhe Zhang,Junwei Zhang
The position of the catalyst in a plasma reactor has an important effect on performance of plasma driven catalytic reaction. An operando diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and mass spectrometry (MS) has been used to investigate CO oxidation on MnO 2 catalyst in in-plasma catalysis (IPC) and post-plasma catalysis (PPC) configurations. It was found that the catalyst in IPC configuration has higher CO conversion and CO 2 selectivity than that in PPC configuration. Operando DRIFTS-MS analysis showed that the IPC configuration generated more reactive oxygen species (M O) on the catalyst surface than the PPC configuration, where M O, M 2+ -O 2 2– , and M + O 2 – are important reactive species promoting CO oxidation to monodentate carbonate that is easy to gasify to gaseous CO 2 . The physical adsorbed O 3 on the catalyst in PPC configuration converts to M 2+ -O 2 2– which combines with CO to form bidentate carbonates that is difficult to gasify to gaseous CO 2 . The mechanisms of CO oxidation on the catalyst in IPC and PPC configurations are discussed.
研究领域:
化学工程
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催化科学
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DOI
高影响因子
WATER AIR AND SOIL POLLUTION
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2025
·Vol. 236
·期 7
·1-16
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IF 3
Jiang Yinying,Yu Jiang,Huang Zhi,Yu Jie,Deng Siwei,Zhu Weiwei,Zeng Zixin
Metformin (MET), recognized as the most extensively consumed pharmaceutical globally, exhibits minimally metabolized and is predominantly excreted unchanged. To remove MET from water, this study synthesized Fe 3 O 4 @MnO 2 (FM) catalysts, which could be easily recoverable using magnets. Notably, Fe 3 O 4 nanospheres, characterized by their superior crystallinity, significantly altered the morphology and structure of the externally wrapped MnO 2 . This modification resulted in an expanded surface area and an increased number of active sites. Furthermore, ultrasound (US) was employed to assist in peroxymonosulfate (PMS) activation, ensure effective dispersion of FM-5, and enhance the homogeneity of the reaction system. The synergistic application of US and FM-5 successfully activated PMS, achieving a remarkable MET degradation efficiency of 98.89% within 80 min, predominantly via a pathway governed by ·O 2 − and 1 O 2 . The FM-5/US/PMS system demonstrated robust adaptability under various environmental conditions. An analysis of the correlation mechanism revealed enhanced MET decomposition under alkaline conditions, thereby broadening the pH adaptation range of FM-5/US/PMS. Using density functional theory (DFT) calculations and HPLC–MS detection to propose degradation products, this study identified a product with comparatively lower toxicity. This work could offer a reference for further development of high performance and eco-friendly catalyst. Graphical
研究领域:
环境科学
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材料科学
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药学
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DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
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2023
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IF 4.7
Mingxia Yang,Senqing Fan,Jiaojiao Chen,Yu Chen,Chuang Li,Jiaxin Meng,Haijie Qing,Yangchao Liu,Zeyi Xiao
An electrocatalytic membrane structured reactor (EMSR) fabricated by loading MnO 2 catalyst in Ti membrane pores for oxidation of n-propanol coupled with hydrogen evolution. During the process of n-propanol oxidation coupled with hydrogen evolution by MnO 2 @Ti EMSR via flow-through mode, the conversion rate of n-propanol was increased by 44%, the selectivity of propionic acid was increased by 33%, and the Faraday efficiency was increased by 59%, compared with those of MnO 2 /Ti membrane with MnO 2 immobilized on the membrane surface. Enhanced contact and mass transfer are two contributors for the catalytic performance improvement by MnO 2 @Ti EMSR via flow-through mode. Besides, the cell voltage during n-propanol oxidation coupled with hydrogen production is decreased by 305 mV with energy consumption reduced by 0.73 kWh Nm H2 -3 , compared with those of hydrogen evolution by water splitting with oxygen evolution reaction. The achievements of this work provide a promising strategy for coproduction of propionic acid and hydrogen.
研究领域:
化学工程
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环境科学
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能源科学
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DOI
高影响因子
CATALYSIS TODAY
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2020
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IF 5.825
Linhao Yu,Hong Chen,Zhe Wen,Mengmeng Jin,Zewei Ma,Xueli Ma,Yushuai Sang,Mengmeng Chen,Yongdan Li
Selective oxidation of 5-hydroxymethylfurfural (HMF) to 2, 5-diformylfuran (DFF) with molecular oxygen is realized with an α-MnO 2 catalyst under mild conditions. In this work, α-MnO 2 exhibited the best performance among the samples examined. Meanwhile, solvent shows a significant effect on the product selectivity and isopropanol is found good for improving the selectivity of DFF. 93.2 % conversion of HMF was achieved at 140 °C for 4 h with 84.3 % selectivity of DFF. Moreover, α-MnO 2 catalyst keeps good reusability in recycling for five times. The reaction pathway indicated that the lattice oxygen species on α-MnO 2 is involved in the selective oxidation of hydroxyl group in HMF molecule.
研究领域:
催化化学
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绿色化学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2024
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IF 7.7
Yingchun Sun,Ru Liu,Yuhui Sun,Ling Long
Formaldehyde (HCHO) poses a significant threat as a common indoor air pollutant, leading to various health issues. However, effectively addressing HCHO removal at room temperature remains a considerable challenge. This paper presents the preparation of a robust, eco-friendly, and biodegradable composite cellulose nanofiber film, incorporating CeO 2 -Ag@MnO 2 catalysts and TEMPO-oxidized cellulose nanofiber (TOCNF), for high-efficiency HCHO removal at room temperature. A CeO 2 -Ag@MnO 2 ternary catalyst with a core–shell structure was constructed to enhance the catalytic oxidation activity and stability. This structure increased the number of active sites on the catalyst surface and enhanced the interfacial synergistic effect of Ce-Ag-Mn. The TOCNF physically adsorbed HCHO in the composite film , while the catalyst oxidized it to CO 2 and water. The composite films, particularly those with 20 wt% CeO 2 -Ag@MnO 2 catalyst, exhibited high HCHO removal rates of 91.2 % at 20 °C and 99.6 % at 60 °C. Furthermore, the TOCNF/20 CAM composite films demonstrated excellent mechanical properties and degradability. This composite film offers an efficient and eco-friendly solution for the catalytic oxidation of HCHO at room temperature.
研究领域:
环境科学
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材料科学
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纳米技术
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催化
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产品关联
DOI
PubMed
高影响因子
Reaction Kinetics Mechanisms and Catalysis
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2025
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IF 1.7
Cheng Lijun,Lei Juan,Ren Xiaoli,Chang Hong,Ju Baihe
In this study, a series of La-α-MnO 2 catalysts with different La doping amounts were prepared by hydrothermal method. It was found that the introduction of La could reduce the crystallinity of α-MnO 2 and increase the specific surface area of the catalyst. Furthermore, La doping can significantly weaken the Mn–O bond, increase the surface Mn 3+ and O ads content, and enhance the oxygen mobility and low-temperature reducibility. The catalytic results indicated that La doping could significantly improve the catalytic oxidation performance of toluene, and 1%La-α-MnO 2 catalyst exhibited the best catalytic activity for toluene oxidation. The toluene conversion rate reaches 90% when the reaction temperature is only 215 °C. In addition, 1%La-α-MnO 2 catalyst presented good stability and repeatability during 50 h durability test under water vapor.
研究领域:
催化化学
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环境科学
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材料化学
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化学工程
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产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
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2023
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IF 7.7
Xixi Chen,Wanyi Fu,Yulong Yang,Yanjun Li,Kai Yang,Xuanbo Xu,Xihui Zhang
Atomic H* has been reported to be thermodynamically feasible for activating hydrogen peroxide (H 2 O 2 ) to produce radicals, while the nonradical pathway and the contributions of metal sites and atomic H* in H 2 O 2 activation need further exploration. In this study, a TiO 2 @MnO 2 catalyst was synthesized via a facile hydrothermal method and surprisingly found to produce atomic H* over Mn sites in water without external energy input (e.g., light and electricity). Atomic H* plays an essential role in the activation of H 2 O 2 via a nonradical pathway, which induces the removal of tiamulin up to 80.4–91.7% in 20 min at a wide pH range of 4.0–11.0. Density function theory calculations prove that atomic H* owns a much lower total energy barrier (ΔG total = 0.68 eV) for the decomposition of H 2 O 2 to generate superoxide and singlet oxygen than Mn sites (ΔG total = 2.90 eV). This study is a re-visit to the mechanism of activating H 2 O 2 via atomic H* for efficient degradation of emerging organic contaminants .
研究领域:
环境科学
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催化
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水处理
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化学工程
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DOI
高影响因子
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