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Surprising separation selectivity of ethylene from ethane over pure siliceous zeolites with framework flexibility

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Science China Materials 2018年第5期61卷 763-764页

作者： Xiangju Meng feng-shou xiao Department of Chemistry Zhejiang University

Recovery and purify of light olefins from the off-gas ofthe catalytic crackers have been focused for more than50 years, driven largely by the escalating demand forfeedstock for production of polyethylene and poly-propylene, which requires the separation of C2H4/C2H6and C3H6/C3H8 mixtures in which the olefins and paraf-fins are present at roughly equal concentrations [1,2].

关键词：中国科学材料科学

Targeted synthesis of zeolites from calculated interaction between zeolite structure and organic template

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National Science Review 2022年第9期9卷 67-78页

作者： Qinming Wu Huimin Luan feng-shou xiao Key Lab of Biomass Chemical Engineering of Ministry of Education College of Chemical and Biological Engineering Zhejiang University Key Lab of Applied Chemistry of Zhejiang Province Department of Chemistry Zhejiang University

Zeolites,a class of silica-based porous materials,have been widely employed in the chemical industry for uses such as sorption,separation,catalysis and ion ***,the synthesis of zeolites is performed in the presence of organic templates via a trial-and-error route,which is labor-intensive and *** recent years,theoretical simulation from the interaction between a zeolite structure and an organic template has been used to guide the synthesis of zeolites,which is *** this review,recent progress in the targeted synthesis of zeolites from interaction between a zeolite structure and an organic template are briefly outlined including the design of new templates for zeolite synthesis,preparation of zeolites with new composition,development of novel routes for zeolite synthesis,synthesis of intergrowth zeolites,generation of novel zeolite structures,control of zeolite morphology and modulation of aluminum distribution in *** targeted syntheses reveal that the minimum energy principle from the theoretical simulation is key for guiding zeolite *** review will be important for zeolite researchers for rationally synthesizing zeolites and effectively designing new zeolite structures.

关键词： zeolite organic template targeted synthesis interaction energy theoretical simulation

Theoretical design for zeolite synthesis

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Science China Chemistry 2022年第9期65卷 1683-1690页

作者： Qinming Wu Huimin Luan feng-shou xiao Key Lab of Biomass Chemical Engineering of Ministry of Education College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China Key Lab of Applied Chemistry of Zhejiang Province Department of ChemistryZhejiang UniversityHangzhou 31007China

Zeolites,an important class of microporous crystals,have been widely utilized in the fields of catalysis,ion-exchange,separation,and sorption for a long *** general,zeolites are synthesized in the presence of costly organic templates under hydrothermal conditions by trial-and-error method,which is not only environmentally unfriendly but also *** recent years,novel concepts of design for zeolite synthesis,which are sustainable,cheap,simple,and efficient,have been *** this review,the recent advances in design for zeolite synthesis will be briefly summarized,mainly including the design of organic templates for directing the formation of zeolites,design of organotemplate-free route for zeolite synthesis,design of solvent-free strategy for zeolite synthesis,design for novel interzeolite transformation,and targeted control of zeolite *** review might be helpful for developing sustainable routes for targeted synthesis of zeolites in the future.

关键词： zeolite organic template organotemplate-free solvent-free interzeolite transformation morphology control

New routes for the construction of strong metal-support interactions

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Science China Chemistry 2022年第11期65卷 2051-2057页

作者： Hai Wang Liang Wang feng-shou xiao Key Lab of Biomass Chemical Engineering of Ministry of Education College of Chemical and Biological EngineeringZhejiang UniversityHangzhou310027China College of Chemistry Zhengzhou UniversityZhengzhou 450001China

Supported metal nanoparticles(NPs)on solid carriers are highly efficient catalysts in many industrial ***,the sintering and/or leaching of metal NPs occurred under harsh reaction conditions that caused the catalyst *** metal-support interactions(SMSIs)serve as an effective method to stabilize the metal NPs against sintering and leaching,which have been extensively *** addition to the classical route to construct SMSIs via high-temperature reduction treatments,new routes have emerged recently to extend the scope of catalysts with SMSIs and optimized their catalytic *** this review,we briefly summarize these routes that avoid the high-temperature reduction treatments for the construction of *** significant advantages in stabilizing metal NPs,modulating the geometric/electronic structure of metal species,and the mechanism on the SMSI formation are particularly ***,the current challenges and developing trends in the construction of SMSIs for achieving more efficient catalysts are outlooked.

关键词： strong metal-support interaction supported catalyst metal nanoparticles heterogeneous catalysis

Efficient adjustment of product selectivity using controllable Pd nanoparticles in nitroarene hydrogenation

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Particuology 2020年第1期18卷 13-18页

作者： Jian Zhang Liang Wang Fang Chen feng-shou xiao Key Laboratory of Applied Chemistry of Zhejiang Province and Department of Chemistry Zhejiang UniversityHangzhou 310028China

Product selectivity adjustment is a much-studied topic in mesoscience that is critical for industrial processes and strongly related to reaction intermediates formed by interactions between catalytic active sites and ***,we report efficient adjustment of the product selectivity in the hydrogenation of substituted nitroarenes via rational reaction intermediates achieved using controllable Pd *** nanoparticles fixed within zeolite Beta crystals(Pd@Beta)afforded rational Pd-NO2 interactions,in which the Pd nanoparticle-adsorbed substituted nitroarenes,such as nitrobenzaldehyde,were reasonably hydrogenated into the corresponding ***,for Pd nanoparticles supported on the external surfaces of zeolite beta crystals,various side products were obtained owing to the coexistence of Pd-NO2 and Pd-C=O *** Pd nanoparticles were artificially controlled in various positions in a fixed-bed reactor,the product selectivity was significantly *** results demonstrate the importance of molecular adsorption and diffusion processes in adjusting product selectivity in catalytic reactions.

关键词： Product selectivity Nitroarene hydrogenation Pd nanoparticles Zeolite crystals

Solvent-free synthesis of zeolite catalysts

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Science China Chemistry 2015年第1期58卷 6-13页

作者： Xiangju Meng Qinming Wu Fang Chen feng-shou xiao Key Lab of Applied Chemistry of Zhejiang Province Department of Chemistry Zhejiang University

The most used method for preparation of zeolites is hydrothermal synthesis from silicate or aluminosilicate gels at temperatures in the range of 60-200 ℃. Excess water used in the industrial process results in several issues, including high autogeneous pressure, low efficiency, pollution, etc. To solve these problems, several strategies have been developed. This review describes the solvent-free synthesis of zeolites. The combination of solvent-free synthesis and organotemplate-free synthesis can open the pathway to a highly sustainable zeolite synthesis protocol in industry.

关键词： zeolites solvent-free sustainable

Fischer-Tropsch reaction within zeolite crystals for selective formation of gasoline-ranged hydrocarbons

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Journal of Energy Chemistry 2021年第3期30卷 429-433页

作者： Chengtao Wang Wei Fang Liang Wang feng-shou xiao Key Lab of Biomass Chemical Engineering of Ministry of Education College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027ZhejiangChina Department of Chemistry Zhejiang UniversityHangzhou 310028ZhejiangChina

Product selectivity control is attractive in Fischer-Tropsch(F-T)synthesis but it is still a challenge,because the F-T products follow the Anderson-Schulz-Flory(ASF)distribution with maximized gasoline-ranged(C_(5)-C_(11))hydrocarbon selectivity at 45%.Herein,we report a strategy by optimizing the gasoline selectivity to outperform the ASF *** key to this success is fixation of the metal nanoparticles within zeolite crystals(metal@zeolite),where the zeolite micropore adjusts the product *** example,the Ru@NaY exhibited the gasoline selectivity 64.3% in the F-T reaction,which is significantly higher than the ASF limitation and about 2 times of that(32.8%)over conventionally supported Ru catalyst(Ru/NaY).This investigation might offer an alternative route for the direct transformation of syngas to liquid fuels with controllable selectivities.

关键词： F-T synthesis Zeolite Ru nanoparticles Gasoline

Insights into the Organotemplate-Free Synthesis of Zeolite Catalysts

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Engineering 2017年第4期3卷 567-574页

作者： Yeqing Wang Qinming Wu Xiangju Meng feng-shou xiao Key Lab of Applied Chemistry of Zhejiang Province Department of Chemistry Zhejiang University Hangzhou 310007 China

As the most important nanoporous material, zeolites, which have intricate micropores, are essential heterogeneous catalysts in industrial processes. Zeolites are generally synthesized with organic templates under hydrothermal conditions; however, this method is environmentally unfriendly and costly due to the formation of harmful gases and polluted water. This article briefly summarizes the role of organic templates and describes designed routes for the organotemplate-free synthesis of zeolites, aided by zeolite seeds and zeolite seeds solution. Furthermore, this review explicates that the micmpore volume decreases with an increase of the Si/Al ratios in the organotemplate-free synthesis of zeolite products, where Na^＋ exists as an alkali cation. This feature is very important in directing the synthesis of zeolite catalysts with controllable Si/AI ratios under organotemplate-free conditions, and is thus important for the efficient design of zeolites.

关键词： Zeolite seed-directed synthesis Organotemplate-free synthesis Zeolite seeds solution Si/Al ratiosZeolite micropore volume

Mesoporous zeolites for biofuel upgrading and glycerol conversion

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Frontiers of Chemical Science and Engineering 2018年第1期12卷 132-144页

作者： Jian Zhang Liang Wang Yanyan Ji Fang Chen feng-shou xiao Key Laboratory of Applied Chemistry of Zhejiang Province and Department of Chemistry Zhejiang University Hangzhou 310028 China Key Laboratory of Biomass Chemical Engineering of Ministry of Education Zhejiang University Hangzhou 310027 China

With the recent emphasis and development of sustainable chemistry, the conversion of biomass feed- stocks into alternative fuels and fine chemicals over various heterogeneous catalysts has received much attention. In particular, owing to their uniform micropores, strong acidity, and stable and rigid frameworks, zeolites as catalysts or co-catalysts have exhibited excellent catalytic performances in many reactions, including hydrodesulfurization, Fischer-Tropsch synthesis, and hydrodeoxygenation. However, the relatively small sizes of the zeolite micropores strongly limit the conversion of bulky biomolecules. To overcome this issue, mesoporous zeolites with pores larger than those of biomolecules have been synthesized. As expected, these mesoporous zeolites have outperformed conventional zeolites with improved activ- ities, better selectivities, and longer catalyst lives for the upgrading of pyrolysis oils, the transformation of lipids into biofuels, and the conversion of glycerol into acrolein and aromatic compounds. This review briefly summarizes recent works on the rational synthesis of mesoporous zeolites and their superior catalytic properties in biomass conversion.

关键词： biomass conversion mesoporous zeolite sustainable chemistry