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Vicinal hydroxyl group-inspired selective oxidation of glycerol to glyceric acid on hydroxyapatite supported Pd catalyst

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Green Energy & Environment 2022年第4期7卷 691-703页

作者： Difan Li Xiuge Zhao Qingqing Zhou Bingjie Ding Anna Zheng Qingpo Peng Zhenshan Hou key laboratory for advanced materials Research Institute of Industrial CatalysisSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai200237China

Selective oxidation of glycerol provides a feasible route towards the sustainable synthesis of high value-added chemicals.Herein,the hydroxyapatite(HAP)supported palladium(Pd)species were fabricated by impregnation and subsequent calcination.The as-obtained heterogeneous Pd catalyst afforded not only excellent selectivity to glyceric acid(GLA)up to 90%with 59%conversion of glycerol but also good recyclability by using molecular oxygen as an oxidant under mild conditions.The characterization of catalysts indicated that both the surface basicity and Pd sites on the catalyst played a crucial role in promoting glycerol oxidation.Notably,it demonstrated that the presence of the vicinal hydroxyl group of glycerol molecule can assist the oxidation reaction via forming a coordination between the vicinal hydroxyl group and Ca^(2+) sites on HAP-derived catalysts.In this catalytic process,the secondary hydroxyl of glycerol kept untouched and the primary hydroxyl of glycerol was converted into carboxyl group,while the Pd species acted as active centers for cooperatively promoting the subsequent oxidation to generate GLA.Additionally,this catalytic system can be extended widely for the oxidative conversion of other vicinal diols into the corresponding a-hydroxycarboxylic acids selectively.Isotope labeling experiment using H_(2)^(18)O confirmed that H_(2)O not only acted as solvent but also was involved in the catalytic cycles.On the basis of the results,a possible reaction mechanism has been proposed.The HAP-supported Pd catalytic system has been shown to serve as an effective approach for the upgrading of bio-derived vicinal diols to high value-added chemicals.

关键词： Hydroxyapatite Palladium Glycerol oxidation Glyceric acid Vicinal hydroxyl group

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Surface pits stabilized Au catalyst for low-temperature CO oxidation

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Rare Metals 2022年第9期41卷 3060-3068页

作者： Ya-Feng Cai Chen Fei Cheng Zhang Jie Yang Li Wang Wang-Cheng Zhan Yang-Long Guo Xiao-Ming Cao Xue-Qing Gong Yun Guo Key Laboratory for Advanced Materials and REsearch Institute of Industrial Catalysis School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai200237China

Development of active and stable catalysts for low-temperature CO oxidation has long been regarded as a hot topic.In this contribution,we used CeO_(2) with high-density surface pits as support to prepare an active and stable Au/CeO_(2) catalyst by an adsorption-deposition method.The obtained 0.05 wt%Au/CeO_(2)-TD(where TD represents thermal decomposition)can maintain its activity at 80℃ for more than 20 h or even after calcination at 800℃ for 2 h.The characterization results showed that the high-density surface pits on CeO_(2)-TD play a decisive role in the stabilization of Au and enhancement of the redox property.This work may provide a new strategy to improve the stability of supported metal catalysts by a simple and conventional method.

关键词： Au catalyst CeO_(2) Surface defect Stability CO oxidation

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Understanding the role of tungsten on Pt/CeO_(2)for vinyl chloride catalytic combustion

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Journal of Rare Earths 2022年第9期40卷 1462-1470,I0005页

作者： Qifeng Zhang Zhengbo Zhou Tian Fang Han Gu Yanglong Guo Wangcheng Zhan Yun Guo Li Wang Key Laboratory for Advanced Materials and REsearch Institute of Industrial Catalysis School of Chemistry&Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

Spherical CeO_(2)synthesized by the hydrothermal process was used as support to prepare Pt/WO_(3)/CeO_(2),and the effects of tungsten(W)contents on activity,stability and polychlorinated by-products were investigated to understand the role of W for vinyl chloride(VC)catalytic oxidation.The introduction of12 wt%W to Pt/CeO_(2)(P12 WC)exhibits the highest catalytic activity with 90%conversion of VC at 250℃,meanwhile the stability improves and the polychlorinated by-products in the tail gas significantly decrease due to the removal of dissociated Cl species in the formation of HCl.The beneficial effects of W on Pt/CeO_(2)are closely related to the chemical state of Pt,redox and surface acid sites distribution.The doped W not only makes Pt disperse evenly on the support with the high valence,but also weakens the interaction between Pt and CeO_(2)by the formation of Pt-O-W and Pt-O-W-O-Ce species,which facilitates oxygen mobility.In addition,the modification of W species also significantly increases the surface acidity amount and changes the distribution of acid sites.

关键词： Tungsten oxides Vinyl chloride Catalytic oxidation Pt/CeO_(2) By-products Rare earths

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Insight into the photoexcitation effect on the catalytic activation of H_(2) and C-H bonds on TiO_(2)(110)surface

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Chinese Chemical Letters 2022年第10期33卷 4705-4709页

作者： Min Zhou Hai-Feng Wang key laboratory for advanced materials Centre for Computational Chemistry and Research Institute of Industrial CatalysisEast China University of Science and TechnologyShanghai 200237China

Semiconductor photocatalysis holds great promise for breaking the inert chemical bonds under mild condition;however,the photoexcitation-induced modulation mechanism has not been well understood at the atomic level.Herein,by performing the DFT+U calculations,we quantitatively compare H_(2) activation on rutile TiO_(2)(110)under thermo-versus photo-catalytic condition.It is found that H2 dissociation prefers to occur via the heterolytic cleavage mode in thermocatalysis,but changes to the homolytic cleavage mode and gets evidently promoted in the presence of photoexcited hole(h^(+)).The origin can be ascribed to the generation of highly oxidative lattice O-radical(O_(br)^(·−))with a localized unoccupied O-2p state.More importantly,we identify that this photo-induced promotion effect can be practicable to another kind of important chemical bond,i.e.,C-H bond in light hydrocarbons including alkane,alkene and aromatics;an exception is the C(sp^(1))-H in alkyne(HC≡CH),which encounters inhibition effect from photoexcitation.By quantitative analysis,the origins behind these results are attributed to the interplay between two factors:C-H bond energy(E_(bond))and the acidity.Owing to the relatively high E_(bond) and acidity,it favors the C(sp^(1))-H bond to proceed with the heterolytic cleavage mode in both thermo-and photo-catalysis,and the photoexcited O_(br)^(·−)is adverse to receiving the transferred proton.By contrast,for the other hydrocarbons with moderate/low E_(bond),the O_(br)^(·−)would enable to change their activation mode to a more favored homolytic one and evidently decrease the C-H activation barrier.This work may provide a general picture for understanding the photocatalytic R-H(R=H,C)bond activation over the semiconductor catalyst.

关键词： Density functional theory calculation Photocatalysis H_(2)activation C-H bond activation TiO_(2)

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Cationic quaternary ammonium-stabilized Nb oxoclusters catalyze reductive amination of carbon dioxide with hydrosilane

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Green Chemical Engineering 2022年第2期3卷 146-156页

作者： Yuan Ma Xinjian Wei Jian Fang Qingpo Peng Wen Xu Zhenshan Hou key laboratory for advanced materials Research Institute of Industrial CatalysisSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai200237China

The N-formylation of amines with CO_(2)and hydrosilanes is an emerging yet important reaction in fine chemical industry.Herein,we have reported a methyltrioctylammonium cation(TOMA)stabilized Nb oxocluster catalyst that can effectively realize two electron reduction of CO_(2)and form C-N bond simultaneously,leading to the corresponding formamides.The oxocluster catalyst exhibits excellent catalytic activity to transform secondary and primary amines into the corresponding formamides,with the conversion ranging from 81.5%to 99.2%under room temperature conditions.Furthermore,the Nb oxocluster catalyst shows the unique characteristics of ionic liquids,and it is highly robust and easy to be recycled for five times with negligible loss of catalytic activity.On the basis of the activity tests and structure characterization of Nb catalysts,it was found that TOMA cation played an important role in modulating the Nb oxocluster with high stability and uniform dispersion.The mechanism studies demonstrate that the formylation reaction proceeds through the formation of silyl formate intermediate rather than carbamate,and the Lewis base site of negative oxygen atoms from polyoxoniobate anions can exert a favorable impact on activation both CO_(2)and Si-H bond of PhSiH 3,allowing that N-formylation reaction proceed smoothly under very mild reaction conditions.

关键词： CO_(2) Amine Hydrosilane N-formylation Polyoxoniobate

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Catalytic transfer hydrogenolysis of C–O bonds in lignin model compounds without arene hydrogenation

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Green Chemical Engineering 2022年第1期3卷 25-33页

作者： Kai Cui Xiuge Zhao Qingpo Peng Honghui Gong Xinjia Wei Jiajia Wang Manyu Chen Zhenshan Hou key laboratory for advanced materials Research Institute of Industrial CatalysisSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai200237China

The shortage of resources and the destruction of the environment have caused serious resource and environmental problems shared by all countries around the world. As a ubiquitous renewable resource, biomass has great prospects for replacing fossil energy and attracted attention from the society. The use of catalytic approach to transform biomass into high-value chemicals is an effective way to use biomass efficiently. In this work, Nisupported catalysts has been developed for the selective cleavage of C–O bonds in lignin model compounds with 2-propanol as the hydrogen source solvent. Among these catalysts, it was indicated that zirconium phosphate(Zr P)-supported Ni catalysts were highly efficient and recyclable for alkyl-aryl ether(α-O-4 and β-O-4) cleavage in lignin model compounds. The further investigation demonstrated that the transfer hydrogenolysis of the C–O bond is highly selective, which afforded phenols and aromatics as dominant products without the products arising from hydrogenation of aromatic rings. Through a series of characterization of the catalyst, it was demonstrated that the medium strong acid sites of the Zr P support promoted the cleavage of alkyl-aryl ethers(α-O-4 and β-O-4),and Br?nsted acid sites favored for achieving high selectivity toward C–O bond cleavage. Additionally, Ni(0) sites on the Zr P catalysts were responsible for the catalytic transfer hydrogenolysis.

关键词： C–O bond cleavage Hydrogenolysis Zirconium phosphate Biomass conversion Ni catalysts

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Epoxidation of propylene by molecular oxygen over unsupported AgCu_x bimetallic catalyst

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Rare Metals 2015年第7期34卷 477-490页

作者： Xiang Zheng Yang-Long Guo Yun Guo Qing Zhang Xiao-Hui Liu Li Wang Wang-Cheng Zhan Guan-Zhong Lu key laboratory for advanced materials Research Institute of Industrial Catalysis East China University of Science and Technology

The unsupported Cu and Ag catalysts with different oxidation states were prepared, and their catalytic performances for propylene epoxidation were investigated.The metallic Cu catalyst exhibits much higher catalytic activity and propylene oxide(PO) selectivity than Cu2 O and Cu O catalysts.The Cu0 species are the main active sites for propylene epoxidation, but Cu2 O and Cu O species are in favor of CO2 and acrolein production.The PO selectivity of 54.2 % and propylene conversion of 2.6 % can be achieved over the metallic Cu catalyst at 160 °C in initial stage, but metallic Cu catalyst would be oxidized to Cu2 O during propylene epoxidation, resulting in a sharp decrease in the PO selectivity and propylene conversion.Nanosize Ag Cuxbimetallic catalysts were prepared.It is found that adding Ag to the metallic Cu catalysts can prevent the oxidation of Cu and make Ag Cuxbimetallic catalysts more stable under the condition of propylene epoxidation.The Ag/Cu molar ratio can remarkably affect the catalytic performance of Ag Cuxcatalyst and the selectivity to PO and acrolein.After Ag Cuxwas supported on MOx-modified a-Al2O3, its catalytic performance can be improved and has a close relationship with the acid–base property of support.

关键词： Epoxidation of propylene Propylene oxide Molecular

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Synthesis of mesoporous CeO_2-MnO_x binary oxides and their catalytic performances for CO oxidation

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Journal of Rare Earths 2014年第2期32卷 146-152页

作者：詹望成张欣烨郭杨龙王丽郭耘卢冠忠 key laboratory for advanced materials Research Institute of Industrial CatalysisEast China University of Science and Technology

Mesoporous CeO2-MnOx binary oxides with different Mn/Ce molar ratios were prepared by hydrothermal synthesis and characterized by scanning electron microscopy （SEM）, N2 sorption, X-ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS） and H2 temperature-programmed reduction （H2-TPR）. The characterization results indicated that the CeO2-MnOx catalysts exhibited flower-like microspheres with high specific surface areas, and partial Mn cations could be incorporated into CeO2 lattice to form solid solution. The CeO2-MnOx catalysts showed better catalytic activity for CO oxidation than that prepared by the coprecipitation method. Furthermore, the CeO2-MnOx catalyst with Mn/Ce molar ratio of 1 in the synthesis gel （Ce-Mn-1） exhibited the best catalytic activity, over which the conversion of CO could achieve 90% at 135 ℃. This was ascribed to presence of more Mn species with higher oxida- tion state on the surface and the better reducibility over the Ce-Mn-I catalyst than other CeO2-MnOx catalysts.

关键词： mesoporous composite oxides ceria manganese oxide hydrothermal synthesis CO oxidation rare earths

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Catalytic wet oxidation of N,N-dimethyl formamide over ruthenium supported on CeO_2 and Ce_(0.7)Zr_(0.3)O_2 catalysts

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Journal of Rare Earths 2019年第3期37卷 265-272页

作者： Jiawen Gong Dongzhi Li Li Wang Wangcheng Zhan Yanglong Guo Yunsong Wang Yun Guo Key Laboratory for Advanced Materials and REsearch Institute of Industrial Catalysis School of Chemistry & Molecular Engineering East China University of Science and Technology

A series of Ru supported on CeO_2 and Ce_(0.7)Zr_(0.3)O_2(CeZrO) was prepared by incipient-wet impregnation method and investigated in the catalytic wet oxidation of N,N-dimethyl formamide(DMF) in batch reactor. The physicochemical property of the catalysts was characterized by Brunauer-Emmett-Teller(BET), X-ray diffraction(XRD), H_2 temperature-programmed reduction(H_2-TPR), X-ray photoelectron spectroscopy(XPS) and thermogravimetry(TG). Compared with 3%Ru/CeO_2, 3%Ru/Ce_(0.7)Zr_(0.3)O_2 catalyst exhibits much higher performance for DMF degradation due to the promotion of Ru dispersion and the transfer of active oxygen, and 99% DMF conversion and 97% COD elimination are obtained at 453 K,2.5 MPa oxygen pressure after 5 h. The reaction mechanism of DMF degradation was suggested. The carbonaceous species deposition and oxidation of Ru can be responsible for catalyst deactivation. And the catalyst activity can be recovered by air calcination and H_2 reduction.

关键词： Catalytic wet oxidation N,N-dimethyl formamide Ru Degradation Catalyst deactivation and regeneration Rare earths

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Nano-preparation promoting effectively luminescent properties of one-dimensional rare earth oxides

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Journal of Rare Earths 2012年第11期30卷 1096-1101页

作者：李俊峰卢冠忠谢宝庚王艳芹郭耘郭杨龙 Key Laboratory for Advanced Materials and REsearch Institute of Industrial Catalysis East China University of Science and Technology

Rare earth （La, Nd and Tb） oxides with one-dimensional micro/nanostmcatres were synthesized hydrothermally under facile and mild conditions with two surfactants, and characterized by X-ray diffraction （XRD）, thermal gravimetry （TG）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM） and photoluminescence. The results showed that the synthesized rare earth oxides behaved regular nano- and micro-scale structures. And the morphologies of samples depended on the radii of rare earth ions, with the help of two sur- factants of sodium dodecyl sulfonic and PEG 600. Nanocrystalline La2O3：Eu^3＋ possessed good photoluminescence （PL） property and might be used as a nanosized phosphor, its PL intensity was akered by the doping Eu^3＋ concentration and the optimum concentration of Eu^3＋ was 3 mol.%. In comparison with bulk Eu^3＋/La2O3, Eu^3＋/nano-La2O3 showed better photoluminescence property, nearly equal to that of nanocrtstalline La2O3：Eu^3＋. Tb4O7 microwires showed interesting photoluminescence properties.

关键词： rare earth oxides one-dimensional morphology hydrothermal synthesis luminescence property Eu^3＋ dopant

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