JOURNAL OF CATALYSIS
·
2020
·
IF 7.888
Yunchao Feng,Sishi Long,Guihua Yan,Binglin Chen,Jonathan Sperry,Wanjie Xu,Yong Sun,Xing Tang,Xianhai Zeng,Lu Lin
Manganese catalyzed transfer hydrogenation (CTH) of aldehydes is an attractive method for the synthesis of alcohols. Here, we report a novel and efficient MnO@C-N catalyst for the CTH of biomass-derived 5-hydroxymethylfurfural and other aldehydes to alcohols in high yields. Catalytic experimental studies showed that the MnO and nitrogen-doping are responsible for the high selectivity and high conversion, respectively. Isotopic labelling experiments demonstrated that the CTH of aldehydes to alcohols over MnO@C-N is via a route by direct hydrogen transfer . Kinetic studies revealed that the N-doping can improve the reaction rate and reduce the activation energy of the aldehydes conversion. DFT calculations also indicated that both pyridine N and pyrrolic N doping can reduce the energy barrier for acetone desorption by the interaction between N and hydroxyl-H of alcohol. Furthermore, MnO@C-N showed good recyclability for at least five reaction cycles. We anticipate that these results can drive progress in the manganese catalyzed transfer hydrogenation reaction.
研究领域:
化学
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催化科学
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材料科学
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DOI
高影响因子
Journal of Cleaner Production
·
2020
·
IF 7.246
Zhengchu Yan,Jianxin Zhu,Xiuyi Hua,Dapeng Liang,Deming Dong,Zhiyong Guo,Na Zheng,Liwen Zhang
Polyvinyl alcohol (PVA) is widely used in industries and exists in corresponding effluents. As a refractory water-soluble polymer, PVA is hard to be biologically degraded and may cause membrane blockage problem in reclaiming the wastewater. Therefore, it is necessary for PVA-containing wastewater to be pretreated. In this study, the heterogeneous catalytic ozonation to degrade PVA was investigated. The composition of catalysts was screened, the catalyst preparation and the reaction conditions were optimized, and the degradation mechanism was discussed. According to the results, γ-alumina was selected as support, copper and manganese were selected as active components, and subsequently the complex catalyst, copper-oxygen-manganese/γ-alumina (CMA), was formed. The optimal preparation conditions of CMA were as follows: molar ratio of copper to manganese was 1:2 while loading rate was 4 wt%; copper and manganese loaded on γ-alumina successively by ultrasonic impregnation at 25 °C for 2.5 h, then dried at 100 °C for 4 h, and calcined at 500 °C for 4 h. When the initial concentration of PVA solution was 20 mg/L, the optimal dosage of the catalyst for catalytic ozonation was 100 mg/L. The removal rate of PVA reached 97.8% in 15 min at pH = 7, and 99.3% in 10 min at pH = 10. The leaching of the metals in CMA could be neglected, and the catalyst still had a satisfactory result after five cycles of reuse. The catalytic ozonation followed the mechanism of hydroxyl radical reaction. Although only a small fraction of PVA was mineralized after reaction, the long chains of PVA molecules were broken into smaller pieces. Therefore, it is an effective pretreatment method for reclaiming PVA-containing wastewater.
研究领域:
环境科学
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化学工程
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产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2017
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IF 3.387
Ruimei Fang,Haibao Huang,Wenjun Huang,Jian Ji,Qiuyu Feng,Yajie Shu,Yujie Zhan,Gaoyuan Liu,Ruijie Xie
Coal based activated carbon (AC) was pretreated by peracetic acid solution and used for supporting Mn catalyst towards oxidation of gaseous benzene by catalytic ozonation . The as-obtained activated carbon was characterized by XPS, BET, SEM, and TG technologies. It indicates that peracetic acid solution modification not only raised the quantity of chemisorbed oxygen or water, and hydroxyl group on activated carbon material surface, but also increased the specific surface area and benzene adsorption capacity of activated carbon. Benzene could be completely removed in 300 min and CO 2 selectivity reached to 61.9% over Mn/AC-modified catalyst. A possible catalytic ozonation mechanism of activated carbon which was treated by peracetic acid solution supported Mn catalyst for oxidation of benzene was proposed.
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
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Xiaoli Yang,Yalan Wang,Haoxi Ben,Jia Yang,Wei Jiang,Anders Holmen,Yanqiang Huang,De Chen
Fischer–Tropsch synthesis over CoMn oxides is a surface-catalyzed structure-sensitive reaction. Active site changes greatly alter product distribution. The dynamics and essence of the changes in Co species during the reaction have seldom been explored. Herein, multiple characterizations were applied to confirm that two types of active sites, i.e., Co and Co 2 C, coexist on CoMnO x under the reaction conditions. Apart from the direct participation of carbon species in the reaction, the steady-state isotopic transient kinetic analysis also suggested the mutual transformation of carbon species in Co 2 C. The ratio of the two paths altered with the temperature, thus leading to Co 2 C-rich and Co-rich surfaces at intermediate and high temperatures, respectively. Kinetic calculations and microkinetic modeling showed that Co 2 C-rich surfaces facilitated CO adsorption and suppressed hydrogen adsorption. This gave high carbon-chain growth activity. The Co-rich surfaces showed high vacancy and hydrogen coverages, lowering the CO activation and CH 4 formation energies.
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
CATALYSIS TODAY
·
2020
·
IF 5.825
Hong Du,Miao Jiang,Xiuyun Ma,Peifang Yan,Z. Conrad Zhang
The rapid consumption of fossil resources and the grim environmental situation encourage the application of renewable and clean energy resources. Conversion of biomass, which is a kind of renewable, CO 2 neutral as well as abundant reserves carbon containing resource, is significantly important. The production of fuels from biomass by means of gasification and Fischer-Tropsch synthesis is one of the most promising routes for industrial applications. The wax-free liquid fuels synthesis directly from H 2 -deficient syngas similar to bio-gas is highly advantageous for reducing investment and operating cost. Thus, the Mn-promoted meso-ZSM-5 supported cobalt catalyst was applied for the production of wax-free liquid fuels by catalytic H 2 -deficient syngas conversion in this study. The performance of the reaction was influenced obviously by Mn content. The cobalt dispersion increased with the addition of Mn, whereas the reduction degree decreased after Mn doping. Then, the balance between the dispersion and reduction degree led to the change in CO uptake followed a volcanic curve. The catalyst with moderate amount of Mn (1 wt%) had the suitable cobalt particle size and the maximum CO uptake. Thus, the highest CO conversion was obtained over Co-1Mn/meso-ZSM-5 catalyst thanks to its maximum exposed active sites. The appropriate amount of Mn addition also resulted in the decreasing of CH 4 selectivity. The highest space time yield of liquid fuels was acquired over the Co-1Mn/meso-ZSM-5 catalyst from H 2 -deficient syngas conversion under the moderate conditions.
研究领域:
能源化学
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催化反应工程
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产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2022
·Vol. 32
·期 27
·2200131
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IF 19.924
Lu An,Fan Yang,Cehuang Fu,Xiyang Cai,Shuiyun Shen,Guofeng Xia,Jing Li,Yunzhu Du,Liuxuan Luo,Junliang Zhang
Proton exchange membrane water electrolysis (PEMWE) is a key technology to solve the serious energy and environmental problems. However, the poor durability of electrocatalysts in acidic oxygen evolution reaction (OER) environment hinders the large-scale application of PEMWE. Herein, a robust RuMn electrochemical catalyst with a remarkable durability within 20 000 cyclic voltammetry cycles is reported. Furthermore, RuMn is stable for 720 h at 10 mA cm –2 current density in 0.5 M H 2 SO 4 solution with <100 mV overpotential increase, outperforming the most electrocatalysts reported to date, by far. An amorphous RuO x shell is detected after the OER test, indicating a surface reconstruction process on the catalyst that inhibits steady-state dissolution. Further study demonstrates that the excellent durability of RuMn realized by protective RuO x can be attributed to strong bond strength of Ru, which is supported by density functional theory calculations with high dissolution voltage. Thus, improving the bond strength of Ru extends the design strategy for the Ru-based alloy catalysts with considerable stability.
研究领域:
电化学
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能源材料
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催化科学
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
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2025
·
IF 4.8
Fangchao Wang,Rui Liu,Hongyi Cui,Ali Ramazani,Ali Morsali,Guoying Zhang
The epoxidation of long-chain α-olefins presents a significant challenge in synthetic chemistry, particularly when employing molecular oxygen from air as the sole oxidant under additive-free conditions. In this study, we demonstrate that manganese supported on mesoporous silica (Mn/MSN) effectively catalyzes the aerobic epoxidation of long-chain α-olefins without requiring initiators or sacrificial agents. Mechanistic investigations reveal a synergistic interplay between Mn(II) and Mn(III) species, which facilitates the selective cleavage the peroxo bonds (O–O) in alkyl hydroperoxide intermediates. Strategic incorporation of iron and zirconium into the Mn/MSN framework modulates the manganese oxidation states, enriching the Mn(II)/Mn(III) ratio and achieving a remarkable space-time yield of up to 200 mol epoxide mol⁻¹ Mn h⁻¹ . Radical trapping experiments combined with high-resolution mass spectrometry corroborate the formation of allyl carbon-centered and alkoxy radical intermediates during the reaction. This work provides a feasible strategy for long-chain α-olefin aerobic epoxidation without any additives.
研究领域:
催化化学
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材料科学
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有机合成
✓ 已验证
产品关联
DOI
高影响因子
Chemical Science
·
2021
·Vol. 12
·期 13
·4779-4788
·
IF 9.825
Yong Yang,Mehmed Z. Ertem,Lele Duan
The [fac-Mn(bpy)(CO)3Br] complex is capable of catalyzing the electrochemical reduction of CO2 to CO with high selectivity, moderate activity and large overpotential. Several attempts have been made to lower the overpotential and to enhance the catalytic activity of this complex by manipulating the second-coordination sphere of manganese and using relatively stronger acids to promote the protonation-first pathway. We report herein that the complex [fac-Mn(bpy-CONHMe)(CO)3(MeCN)]+ ([1-MeCN]+; bpy-CONHMe = N-methyl-(2,2′-bipyridine)-6-carboxamide) as a pre-catalyst could catalyze the electrochemical reduction of CO2 to CO with low overpotential and high activity and selectivity. Combined experimental and computational studies reveal that the amide NH group not only decreases the overpotential of the Mn catalyst by promoting the dimer and protonation-first pathways in the presence of H2O but also enhances the CO2 electroreduction activity by facilitating C–OH bond cleavage, making [1-MeCN]+ an efficient CO2 reduction pre-catalyst at low overpotential.
研究领域:
化学
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催化科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ChemistrySelect
·
2022
·Vol. 7
·期 45
·e202201614
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IF 2.307
Yafei Zhao,Ye Zhuang,Kai Ye,Yifei Wu,Changhe Luo,Dan Li,Yi Zhang,Jin Yao,Sajid Ali
Graphical To test the VOCs treatment performance of plasma catalysis at a pilot scale (50 m 3 /h), a novel multi-tube DBD coupled with Ag-MnO x /Al 2 O 3 was built, and the toluene (30 mg/m 3 ) removal efficiency and energy yield achieved by the system were 85.4 % and 5.2 g/kWh at the SED of 39.7 J/L, which were nearly three times as much as the single DBD. A pilot-scale multi-tube dielectric barrier discharge (DBD) reactor coupled with a series of Mn−Ag based catalysts for VOCs abatement was set up and investigated. The DBD with 2 %Ag-MnO x /Al 2 O 3 catalyst exhibited the best performance of removal efficiency (85.4 %) and energy yield (5.2 g/kWh) of toluene at the specific energy density of 39.7 J/L, much higher than the single DBD reactor (34.9 %, 2.1 g/kWh). Moreover, the degradation efficiencies of styrene, dimethyl, ethyl acetate and xylene in the plasma catalysis system were also studied. The catalyst presented high stability during the 50 hours of toluene plasma-catalysis oxidation. Finally, the physicochemical properties of this catalyst were characterized and discussed using an energy dispersive spectrometer, X-ray diffraction patterns, and X-ray photoelectron spectroscopy.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED MATERIALS
·
2024
·Vol. 36
·期 47
·2408301
·
IF 27.4
Decheng Li,Yifan Yu,Chilin Li
Here, a rechargeable carbon fluoride battery is demonstrated with unprecedented high rate and long life by oxygen doping and electrolyte formulation. The introductions of Mn 2+ –O catalyst and porous structure during the oxidation process of CF x cathode can promote the splitting of Li–F during charging. By further modulating the electrolyte with triphenylantimony chloride (TSbCl) as anion acceptor and CsF as product modulator, the more readily dissociable CsLiF 2 product instead of LiF is preferentially formed, and the TSbCl-salt protection interface is constructed to confine Li–F based products and reduce fluoride loss at cathode side. These effects endow Li-CF x batteries with durable reversible conversion reaction (for at least 600 cycles), ultrahigh rate performance (e.g., 364 mAh g −1 at 20 A g −1 ) and low charging plateau voltage down to 3.2 V. The cathode exhibits the maximum power density of 38342 W kg −1 and energy density of 1012 Wh kg −1 . Furthermore, this Li-CF x system demonstrates the promising prospects for applications in view of its low temperature operation (e.g., 280 mAh g −1 at −20 °C), low self-discharge ability, large-scale pouch cell fabrication and high cathode loading (5–6 mg cm −2 ), enabling it to move beyond previous role as primary battery and into new role as fast-charging rechargeable battery with high energy density.
研究领域:
能源材料
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电化学
·
储能技术
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Dengtai Wang,Luxiang Jiang,Mingjiao Tian,Jing Liu,Yi Zhan,Xiaoxiao Li,Zuwu Wang,Chi He
Developing cost-effective monolith catalyst with superior low-temperature activity is critical for oxidative efficacious removal of industrial volatile organic compounds (VOCs). However, the complexity of the industrial flue gas conditions demands the need for high moisture tolerance, which is challenging. Herein, CoMn–Metal Organic Framework (CoMn–MOF) was in situ grown on Ni foam (NiF) at room temperature to synthesize the cost-effective monolith catalyst. The optimized catalyst, Co1Mn1/NiF, exhibited excellent performance in toluene oxidation ( T 90 = 239 °C) due to the substitution of manganese into the cobalt lattice. This substitution weakened the Co–O bond strength, creating more oxygen vacancies and increasing the active oxygen species content. Additionally, experimentally and computationally evidence revealed that the mutual inhibiting effect of three typical aromatic hydrocarbons (benzene, toluene and m–xylene) over the Co1Mn1/NiF catalyst was attributed to the competitive adsorption occurring on the active site. Furthermore, the Co1Mn1/NiF catalyst also presents outstanding water resistance, particularly at a concentration of 3 vol%, where the activity is even enhanced. This was attributed to the lower water adsorption and dissociation energy derived from the interaction between the bimetals. Results demonstrate that the dissociation of water vapor enables more reactive oxygen species to participate in the reaction which reduces the formation of intermediates and facilitates the reaction. This investigation provides new insights into the preparation of oxygen vacancy–rich monolith catalysts with high water resistance for practical applications.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Science Bulletin
·
2025
·
IF 21.1
Ziyan Guo,Pengxiang Qiu,Huan Song,Can Ye,Yaning Du,Keding Lu
The mechanisms that produce atmospheric sulfate, a critical PM 2.5 constituent, must be elucidated to inform air quality interventions. Current evidence indicates that manganese-catalyzed heterogeneous SO 2 oxidation is a dominant sulfate source. We demonstrate that black carbon (BC) critically enhances this process through interfacial electronic interactions with HSO 3 − /SO 3 2− species, reducing SO 2 oxidation barriers while increasing reactive oxygen species (ROS) generation ( 1 O 2 , •O 2 − , and •OH). Unique sulfur isotopic signatures measured in BC-Mn 2+ /O 2 systems confirm a novel oxidation pathway in which BC facilitates electron transfer during O 2 -activated SO 2 conversion. Multiphase modeling revealed that under typical haze conditions, BC-mediated catalysis produces sulfate at higher rates than traditional Mn-only pathways. The synergistic BC–Mn system enables continuous redox cycling via O 2 activation, establishing BC as an active electronic modulator rather than a passive substrate in sulfate formation. These findings redefine the role of BC in atmospheric chemistry, offering a molecular basis for targeted sulfate aerosol control.
研究领域:
大气化学
·
环境科学
·
气溶胶化学
·
表面催化
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分子地球化学
·
空气污染控制
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）