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Catalytic behavior of Mo-Bi-Fe-Co-K-M-O(M=Ce,Gd,CeGd)catalysts for selective oxidation of isobutene

Journal of Rare Earths 2024年第1期42卷 84-93,I0003页

作者： Qinghui Li Huahua Zhao Jian Yang Jun Zhao Liang Yan Huanling Song Lingjun Chou State Key Laboratory for Oxo Synthesis and selective oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000China University of Chinese Academy of Sciences Beijing100049China

The further improvement of methacrolein(MAL)selectivity from isobutene(IB)oxidation is crucial and challenging.In this study,based on the typical Mo-Bi-Fe-Co-K-O mixed metal oxide,the rare earth element Gd-doped,Ce-doped and CeGd co-doped catalysts were prepared by co-precipitation strategy to increase the selectivity of MAL from 47.9%to 49.8%,64.2% and 68.6%,respectively.In order to elucidate in-depth the promoting effect of Ce and/or Gd,various characterizations were utilized including X-ray diffraction patterns(XRD),Raman,X-ray fluorescence spectrometry(XRF),X-ray photoelectron spectroscopy(XPS),O_(2)-temperature programmed desorption(O_(2)-TPD),H2-temperature programmed reduction(H2-TPR),CO_(2)-temperature programmed desorption(CO_(2)-TPD),IB-temperature programmed desorption(i-C4-TPD)and in-situ IB-Fourier transform infrared spectroscopy(IB-FTIR).Both Ce and Gd finely regulate the bulk and surface structure of the catalyst,thus altering the redox ability,oxygen mobility and storage ability and basicity.Compared with Ce,Gd addition slightly regulates the variation of Co^(2+)/Co^(3+)redox couples,greatly enhances the interaction among the components on the catalyst,thus only increases the content of surface oxygen species and has little effect on their mobility.While Cecontaining catalyst performs stronger oxygen storage and migration ability,thus leading to the overproduction of surface Odefectspecies,which are proposed to be the active sites for the production of MAL and COx.The CeGd co-doped catalyst possesses the proper content of surface Odefectspecies,thus exhibits much higher MAL selectivity.Moreover,the promoting mechanism of Ce and/or Gd over IB oxidation is proposed.Therefore,this work is helpful for understanding the influence of rare earth elements on the structure of mixed metal oxides and the olefin selective oxidation reaction.

关键词： Mixed metal oxide catalyst Rare earth element Isobutene selective oxidation Methacrolein

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Cu,N codoped carbon nanosheets encapsulating ultrasmall Cu nanoparticles for enhancing selective 1,2-propanediol oxidation

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Journal of Energy Chemistry 2024年第4期91卷 27-35页

作者： Yonghai Feng Min Yu Minjia Meng Lei Liu Dewei Rao Institute for Advanced Materials School of Materials Science and EngineeringJiangsu UniversityZhenjiang 212013JiangsuChina School of Chemistry and Chemical Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

In the selective oxidation of biomass-based 1,2-propanediol(PDO)with oxygen as the terminal oxidant,it is challenging to improve the lactic acid(LA)selectivity for nonnoble metal nanoparticles(NPs)due to their limited oxygen reduction rate and easy C-C cleavage.Given the high economic feasibility of nonnoble metals,i.e.,Cu,in this work,copper and nitrogen codoped porous carbon nanosheets encapsulating ultrafine Cu nanoparticles(Cu@Cu-N-C)were developed to realize highly selective of PDO oxidation to LA.The carbon-encapsulated ultrasmall Cu^(0)NPs in Cu@Cu-N-C have high PDO dehydrogenation activity while N-coordinated Cu(Cu-N)sites are responsible for the high oxygen reduction efficacy.Therefore,the performance of catalytic PDO conversion to LA is optimized by a proposed pathway of PDO→hydroxylacetone→lactaldehyde→LA.Specifically,the enhanced LA selectivity is 88.5%,and the PDO conversion is up to 75.1%in an O_(2)-pressurized reaction system(1.0 MPa O_(2)),superior to other Cu-based catalysts,while in a milder nonpressurized system(O_(2)flow rate of 100 mL min-1),a remarkable LA selectivity(94.2%)is obtained with 39.8%PDO conversion,2.2 times higher than that of supported Au nanoparticles(1%Au/C).Moreover,carbon encapsulation offers Cu@Cu-N-C with strong leaching resistance for better recycling.

关键词： selective oxidation Copper and nitrogen doped carbon 1,2-Propanediol Ultrasmall Cu nanoparticles Lactic acid

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2,5-Diformylfuran production by photocatalytic selective oxidation of 5-hydroxymethylfurfural in water using MoS_(2)/CdIn_(2)S_(4) flower-like heterojunctions

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Chinese Journal of Chemical Engineering 2023年第2期54卷 180-191页

作者： Qian Zhu Yan Zhuang Hongqing Zhao Peng Zhan Cong Ren Changsheng Su Wenqiang Ren Jiawen Zhang Di Cai Peiyong Qin National Energy R&D Center for Biorefinery Beijing University of Chemical TechnologyBeijing 100029China Collage of Life Science and Technology Beijing University of Chemical TechnologyBeijing 100029China Research Center for Eco-environmental Sciences Chinese Academy of ScienceBeijing 100085China

The selective oxidation of 5-hydroxymethylfurfural(HMF) into 2,5-diformylfuran(DFF) is an important reaction for renewable biomass building blocks. Compared with thermal catalytic processes, photocatalytic production of DFF from HMF has attracted tremendous attention. Herein, the MoS_(2)/CdIn_(2)S_(4)(MC)flower-like heterojunctions were prepared and considered as photocatalysts for selective oxidation of HMF into DFF under visible-light irradiation in aqueous solution. Results demonstrated MoS_(2) in MC heterojunction could promote the separation of photoexcited electron-hole pairs, while the amount of MoS_(2) dropping was proved influenced on the photocatalytic performance. 80.93% of DFF selectivity was realized when using 12.5% MC as photocatalyst. In addition, the MC catalyst also showed great potential in transformation of other biomass derived benzyl-and furyl-alcohols. The catalytic mechanism suggested that ·O_(2)^(-) was the decisive active radical for HMF oxidation. Therefore, the MC heterojunction could be applied in photocatalytic conversion of biomass to valuable chemicals under ambient condition.

关键词： 2 5-Diformylfuran(DFF) Photocatalysis MoS_(2)/CdIn_(2)S_(4)(MC) selective oxidation Visible light irradiation

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Biomass-based N doped carbon as metal-free catalyst for selective oxidation of D-xylose into D-xylonic acid

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Green Energy & Environment 2022年第6期7卷 1310-1317页

作者： Zengyong Li Yiming Huang Xiao Chi Di Li Linxin Zhong Xuehui Li Chuanfu Liu Xinwen Peng State Key Laboratory of Pulp and Paper Engineering South China University of TechnologyGuangzhou510640China School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou510640China

Rational design and facile preparation of low-cost and efficient catalysts for the selective converting of biomass-derived monosaccharides into high value-added chemicals is highly demanded,yet challenging.Herein,we first demonstrate a N doped defect-rich carbon(NC-800-5)as metal-free catalyst for the selective oxidation of D-xylose into D-xylonic acid in alkaline aqueous solution at 100℃ for 30 min,with 57.4%yield.The doped graphitic N is found to be the active site and hydroxyl ion participating in the oxidation of D-xylose.Hydroxyl ion and D-xylose first adsorb on NC-800-5 surface,and the aldehyde group of D-xylose is catalyzed to form germinal diols ion.Then,C–H bond break to yield carboxylic group.Furthermore,NC-800-5 catalyst shows high stability in recycled test.

关键词： Biomass carbon Metal-free catalysts D-xylose Sugar acid selective oxidation

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Atropisomer-based construction of a new perylene diimide macrocycle as visible-light photocatalyst for selective sulfide oxidation

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Chinese Chemical Letters 2022年第12期33卷 5088-5091页

作者： Fei Yang Miaomiao Zhen Shanshan Wang Wei Wei Huan He Yanqing Xu Key Laboratory of Cluster Science Ministry of Education of ChinaBeijing Key Laboratory of Photoelectronic/Electrophotonic Conversion MaterialsSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China Department of Chemistry Capital Normal UniversityBeijing 100048China Test&Analysis Center of Shougang Technical Research Institute Beijing 100043China

By using a perylene diimine(PDI)syn-atropisomer as highly preorganized precursor,we successfully constructed a visible-light-active organic macrocycle PDI-M.The formation of macrocyclic structure effectively avoids self-aggregation of PDI cores and enhances the absorption in visible region.As a photocatalyst,PDI-M exhibits excellent activity on aerobic selective oxidation of sulfide into sulfoxide under visible light irradiation at room temperature.Mechanism studies show that both superoxide and singlet oxygen act as reactive oxygen species.This work provides a typical case toward the maximum utilization of photosensitive groups under mild conditions.

关键词： Macrocycles Perylene diimine Photocatalysis Atropisomer selective oxidation

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Promotional effect of Cu additive for the selective catalytic oxidation of n-butylamine over CeZrO_(x)catalyst

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Chinese Chemical Letters 2022年第6期33卷 3065-3072页

作者： Xin Xing Ting Zhao Jie Cheng Xiaoxiao Duan Wenpeng Li Ganggang Li Zhongshen Zhang Zhengping Hao National Engineering Laboratory for VOCs Pollution Control Material&Technology Research Center for Environmental Material and Pollution Control TechnologyUniversity of Chinese Academy of SciencesBeijing 101408China College of Environmental Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China

The catalytic elimination of nitrogen-containing volatile organic compounds(NVOCs)still encounters bottlenecks in NO_(x)formation and low N_(2)selectivity.Here,a series of Cu-promoted Ce-Zr mixed oxide catalysts were synthesized using a simple precipitation approach,and n-butylamine was adopted as the probe pollutant to evaluate their catalytic performance.The Ce Cu_(10%)ZrO_(x)catalyst exhibited the best catalytic activity,with 100%n-butylamine conversion and 90%N_(2)selectivity at 250℃.Concurrently,this sample also displayed good water resistance.A detailed characterization of the catalyst was performed through a series of experimental studies and theoretical calculations.The addition of Cu increased the redox property and promoted the production of oxygen vacancies,all of which were favorable for the greatest nbutylamine selective catalytic oxidation performance.The changes of oxygen vacancies over Ce Cu_(10%)ZrO_(x)in reaction process were studied by in situ Raman spectra.Moreover,in situ diffuse reflectance infrared Fourier transform spectra(DRIFTs)and theoretical calculations were employed to explore the reaction mechanism of n-butylamine selective oxidation.The high activity and selectivity of this catalyst confirm the practical feasibility of the selective oxidation of n-butylamine to CO_(2)and N_(2),and the exploration of the reaction mechanism provides new insights into the further design of catalysts.

关键词： N-Butylamine CeCu_(a)ZrO_(x)mixed oxide selective oxidation Oxygen vacancies Reaction mechanism

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selective oxidation of Propane over CsFePVAsMo Heteropoly Compound Catalyst

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Chinese Journal of Chemistry 2004年第8期22卷 831-836页

作者：蔡铁军余长林邓谦彭振山龙云飞吕晓萌 Department of Chemistry & Chemical Engineering Hunan University of Science & Technology Xiangtan Hunan411201 China

Both the partially reduced and non-reduced multi-component heteropoly compound catalysts with Keggin structure were prepared and used for the selective oxidation of propane. The catalysts were characterized by IR, H2-TPR, NH3-TPD, SEM and XRD. The addition of Cs increased the selectivity of acrylic acid and acetic acid. The selective oxidation performance was greatly improved with the addition of As. Among all of the tested catalysts, the catalytic performance of the Cs1.8Fe0.16HxPVAs0.4Mo11O40 (non-reduced) was the best and the maximum yield of acrylic acid reached 16.42%.

关键词： heteropoly compound partially reduced selective oxidation propane acrylic acid

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selective oxidation of CO in Excess H_2 over Ru/Al_2O_3 Catalysts Modified with Metal Oxide

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Journal of Natural Gas Chemistry 2007年第4期16卷 409-414页

作者： Xirong Chen Hanbo Zou Shengzhou Chen Xinfa Dong Weiming Lin School of Chemical and Energy Engineering South China University of Technology Guangzhou 510651 Guangdong China School of Chemistry and Chemical Engineering Guangzhou University Guangzhou 510006 Guangdong China

The Ru/Al2O3 catalysts modified with metal oxide （K20 and La2O3） were prepared v/a incipient wetness impregnation method from RuCl3.nH2O mixed with nitrate loading on Al2O3 support. The activity of catalysts was evaluated under simulative conditions for the preferential oxidation of CO （CO-PROX） from the hydrogen-rich gas streams produced by reforming gas, and the performances of catalysts were investigated by XRD and TPR. The results showed that the activity temperature of the modified catalysts Ru-K20/Al2O3 and Ru-La2O3/Al2O3 were lowered approximately 30℃ compared with pure Ru/Al2O3, and the activity temperature range was widened. The conversion of CO on Ru-K20/Al2O3 and Ru-La2O3/Al2O3 was above 99% at 140-160℃, suitable to remove CO in a hydrogen-rich gas and the selectivity of Ru-La2O3/Al2O3 was higher than that of Ru-K2O/Al2O3in the active temperature range. Slight methanation reaction was detected at 220℃ and above.

关键词： hydrogen-rich gas ruthenium based catalysts CO removal selective oxidation metal oxide

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Oxygen-doped Carbon Nitride Nanocages with Efficient Photon-to-Electron Conversion for selective oxidation of Xylose/Xylan to Yield Xylonic Acid

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Paper And Biomaterials 2023年第2期8卷 53-65页

作者： Junqiang Zhang Zhuoyan Xie Zulfiqar Ali Ning Li Qimeng Liu Wenyue Fan Jiliang Ma Runcang Sun Liaoning Key Lab of Lignocellulose Chemistry and BioMaterials Liaoning Collaborative Innovation Center for Lignocellulosic BiorefineryCollege of Light Industry and Chemical EngineeringDalian Polytechnic UniversityDalianLiaoning Province116034China

Highly efficient photon-to-electron conversion is crucial for achieving photocatalytic conversion.In this study,oxygen-doped carbon nitride nanocages(O@CNNCs)were engineered via dual strategies of morphology-controlled heteroatom doping,which was successfully used in the photocatalytic selective oxidation of xylose/xylan to xylonic acid.The nanocage-shaped O@CNNCs had a larger surface area,which was 4.02 times of carbon nitride(CN).Furthermore,with the assistance of morphology regulation and O-doping,O@CNNCs exhibit highly efficient photon-to-electron conversion,enhanced visible-light utilization,high photocurrent,low resistance,and fast separation/migration of electron-hole pairs.Correspondingly,the photocatalytic oxidation of xylose to xylonic acid using O@CNNCs was successfully achieved under mild reaction conditions with a yield of 83.4%.O@CNNCs have excellent recyclability,in which the yield of xylonic acid in the 5th cycle was 98.2%of its initial use.The O@CNNC photocatalytic system was also suitable for macromolecular xylan,and a xylonic acid yield of 77.34 mg was obtained when 100 mg xylan was used.The oxidation-active species captured experiments indicated that holes were crucial for the selective oxidation of xylose to xylonic acid.Overall,this study provides a new strategy for the preparation of photocatalysts with excellent photon-to-electron conversion and selective oxidation of biomass-derived feedstocks to xylonic acid.

关键词： photon-to-electron conversion morphology regulation oxygen doping selective oxidation xylonic acid

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selective oxidation of methane to formaldehyde by oxygen over silica-supported iron catalysts

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Journal of Natural Gas Chemistry 2009年第3期18卷 288-294页

作者： Jieli He Yang Li Dongli An Qinghong Zhang Ye Wang State Key Laboratory of Physical Chemistry of Solid Surfaces National Engineering Laboratory for Green Chemical Productions of Alcohols Ethers and Esters College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 Fujian China

FeOx-SiO2 catalysts prepared by a sol-gel method were studied for the selective oxidation of methane by oxygen. A single-pass formaldehyde yield of 2.0% was obtained over the FeOx-SiO2 with an iron content of 0.5 wt% at 898 K. This 0.5 wt% FeOx-SiO2 catalyst demonstrated significantly higher catalytic performances than the 0.5 wt% FeOx/SiO2 prepared by an impregnation method. The correlation between the catalytic performances and the characterizations with UV-Vis and H2-TPR suggested that the higher dispersion of iron species in the catalyst prepared by the sol-gel method was responsible for its higher catalytic activity for formaldehyde formation. The modification of the FeOx-SiO2 by phosphorus enhanced the formaldehyde selectivity, and a single-pass formaldehyde yield of 2.4% could be attained over a P-FeOx-SiO2 catalyst （P/Fe = 0.5） at 898 K. Raman spectroscopic measurements indicated the formation of FePO4 nanoclusters in this catalyst, which were more selective toward formaldehyde formation.

关键词： selective oxidation methane formaldehyde iron catalyst sol-gel method

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