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Nano Research 2024年第7期17卷 5884-5896页

作者： Fuwen Yang Jie Zhang Jinwei Chen Gang Wang Tong Yu Qian Li Zongbo Shi Qiushi Sun Runsheng Zhuo Ruilin Wang College of Materials Science and Engineering Sichuan UniversityChengdu 610065China Engineering Research Center of Alternative Energy Materials&Devices Ministry of EducationSichuan UniversityChengdu 610065China REZEL Catalysts Corporation Shanghai 200120China

Pt single atoms catalysts with precise coordination environment and high stability are expected to achieve high performance of propane dehydrogenation(PDH).In this work,an innovative synthetic strategy is proposed to construct the S-1@0.1Pt9Zn@DPS-1 nanocomposite as a highly efficient PDH *** engineering is applied to induce the formation of defective porous silicalite-1(DPS-1),which is favorable for achieving the uniformly distributed ZnO *** ZnO nanoclusters were further served as anchoring sites to stabilize the isolated Pt *** structural characterization revealed that penta-O coordinated Pt single atom coupled with ZnO nanoclusters decorated on the ***,the atomically dispersed Pt atoms with the ideal coordination environment could act as the predominant active sites for PDH *** expected,the optimal S-1@0.1Pt9Zn@DPS-1 catalyst delivered an excellent PDH performance(propane conversion of 40.7%,propylene selectivity of 97.5%)and good cycling regeneration *** work provides a new way for improving the activity and stability of catalysts in the field of industrial catalysts.

关键词： defect engineering single platinum atom coordination environment propane dehydrogenation propylene

Access to High-Molecular-Weight Polyethylenes through High Temperature Ethylene Polymerization Catalysed by Ethylene-Bridged ansa-(3-R-Cyclopentadienyl)(Fluorenyl) Zirconocene Complexes

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Chinese Journal of Polymer Science 2024年第1期42卷 42-51,I0007页

作者： Bo Li Haiyan Ma Jiling Huang Shanghai Key Laboratory of Functional Materials Chemistry and Laboratory of Organometallic Chemistry School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

A series of C1-symmetric ethylene-bridged ansa-(3-R-cyclopentadienyl)(fluorenyl) metallocene complexes(Zr: 1-5;Hf: 6) have been synthesized, characterized and investigated as catalyst precursors for the high temperature ethylene polymerization. Using methylaluminoxane(MAO) as the cocatalyst, zirconium complexes 1-5 bearing a bulky substituent on the 3-position of the cyclopendienyl ring showed high catalytic activities up to 1.48×10^(7) g PE·mol_(Zr)^(-1)·h^(-1) toward the polymerization of ethylene and afforded polyethylenes with high molecular weights(1.49×10^(5)-6.31×10^(5) g/mol), meanwhile exhibting great thermal stability at high temperatures up to 120 ℃ together with a long catalytic life time up to 2 h. By adopting low Al/Zr ratios, such as 125, polyethylenes with ultra high molecular weights up to 2.86×106 g/mol were obtained. It is worthy of noting that zirconium complexes 1-4 bearing a substituent with an aryl pendant showed temperature-dependent activities, which increased rapidly with the increase of polymerization temperature, thus weak interaction of the pendent aryl group with the cationic active center is proposed to account for the very low activities displayed at low temperatures. In contrast to zirconocene complexes 1-5, hafnocene complex 6 only displayed very low catalytic activities toward the polymerization of ethylene and afforded polyethylenes with molecular weights ten times smaller than those obtained by zirconocene complexes 1-5. Zirconocene complexes 1-5 were also able to catalyse the polymerization of propylene at high temperatures, but only afforded waxes with low molecular weights.

关键词： ansa-Metallocene Ethylene propylene Polymerization High temperature

Efficacy of Ca/ZSM-5 zeolites derived from precipitated calcium carbonate in the methanol-to-olefin process

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结构化学 2024年第4期43卷 31-38页

作者： Xinyu You Xin Zhang Shican Jiang Yiru Ye Lin Gu Hexun Zhou Pandong Ma Jamal Ftouni Abhishek Dutta Chowdhury College of Chemistry and Molecular Sciences Wuhan UniversityWuhan430072PR China Omya International AG Froschackerstrasse 64622EgerkingenSwitzerland

In the context of heightened environmental consciousness and the growing demand for light olefins,this study explores the promising future prospects for their sustainable production from renewable *** olefins(especially propylene)are a pivotal constituent of the petrochemical industry,and their demand is poised for steady growth driven by various sectors(e.g.,electric mobility,consumer goods and packaging industries),which should not rely solely on traditional petroleum-led ***,sustainable pathways,such as the methanol-to-olefin(MTO)process catalyzed by zeolites,are gaining *** to couple the future olefin demands with the concept of a"methanol economy",this study investigates the synthesis of hierarchical Ca/ZSM-5 zeolites using a cost-effective approach involving Precipitated Calcium Carbonate(PCC)as a hard template,leading to superior catalytic *** characterization techniques are employed to elucidate the cata-lyst's properties,highlighting the dual importance of mesoporosity and calcium species in optimizing its *** spectroscopy provides in-depth insights into its enhanced anti-coking *** research contributes to expanding the catalyst toolkit for zeolite-catalyzed MTO processes,focusing on propylene production,thereby addressing the increasing demand for light olefins while promoting sustainability and circular economy principles.

关键词： Hierarchical zeolite propylene Precipitated calcium carbonate Methanol-to-olefins Characterization

Selective oxidation using in-situ generated hydrogen peroxide over titanosilicates

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结构化学 2024年第6期43卷 12-14页

作者： Zhipeng Wan Hao Xu Peng Wu State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal UniversityShanghai200062China State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal UniversityShanghai200062China Institute of Eco-Chongming Shanghai202162China

Titanosilicates are a class of heteroatom-containing zeolitic materials with tetrahedrally coordinated Ti4+ions incorporated into crystalline zeolite frameworks,with TS-1,Ti-MWW and Ti-MOR as representative and attractive selective oxidation *** liquid-phase oxidations of a variety of substrates such as olefins and ketones with the green oxidant of H2O2 over titanosilicates under mild conditions have attracted considerable research interests in the clean production of fine and bulk chemicals,among which propylene epoxidation and cyclohexanone ammoximation have been industrialized[1].

关键词： PHASE EPOXIDATION propylene H-2

Mesoporous carbons as metal-free catalysts for propane dehydrogenation: Effect of the pore structure and surface property

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Chinese Journal of Catalysis 2019年第9期40卷 1385-1394页

作者： Zhong-Pan Hu Jin-Tao Ren Dandan Yang Zheng Wang Zhong-Yong Yuan Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) School of Materials Science and EngineeringNankai UniversityTianjin 300350China State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering College of Chemistry and Chemical EngineeringNingxia UniversityYinchuan 750021NingxiaChina

Nanocarbon materials have been used as important metal-free catalysts for various reactions including alkane ***,clarifying the active sites and tuning the nanocarbon structure for direct dehydrogenation have always been significantly challenging owing to the lack of fundamental understanding of the structure and surface properties of carbon ***,mesoporous carbon materials with different pore ordering and surface properties were synthesized through a soft-templating method with different formaldehyde/resorcinol ratios and carbonization temperatures and used for catalytic dehydrogenation of propane to *** highly ordered mesoporous carbons were found to have higher catalytic activities than disordered and ordered mesoporous carbons,mainly because the highly ordered mesopores favor mass transportation and provide more accessible active ***,mesoporous carbons can provide a large amount of surface active sites owing to their high surface areas,which is favorable for propane dehydrogenation *** control the surface oxygenated functional groups,highly ordered mesoporous carbons were carbonized at different temperatures(600,700,and 800℃).The propylene formation rates exhibit an excellent linear relationship with the number of ketonic C=O groups,suggesting that C=O groups are the most possible active sites.

关键词： Mesoporous carbons Propane Dehydrogenation propylene Metal-free catalysis

Effect of pH on the catalytic performance of PtSn/B-ZrO2 in propane dehydrogenation

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Chinese Journal of Catalysis 2020年第4期41卷 719-729页

作者： Zhonghai Ji Dengyun Miao Lijun Gao Xiulian Pan Xinhe Bao State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China

Boron-modified ZrO2(B-ZrO2)was synthesized under various pH values(9,10,and 11)and used as the supports of PtSn catalysts(PtSn/B-ZrO2-x)for non-oxidative dehydrogenation of *** NH3-TPD and pyridine IR show that only Lewis acid is present and the acid strength increases with the synthesis ***/B-ZrO2-10 exhibits the best catalytic performance with an initial propane conversion of 36%and a deactivation rate constant(kd)of 0.0127 h^-*** XPS results indicate that the electronic properties of Pt and SnOx are affected not only by their interaction but also by the interaction with *** a careful analysis of the oxygen storage capacity and activity in CO oxidation,it is hypothesized that the interaction between Pt and Sn becomes stronger following the order:PtSn/B-ZrO2-9

关键词： Propane dehydrogenation Platinum-tin propylene Support Stability

Supported Ziegler-Natta catalysts from MgCl_(2)·nROH precursors and its catalytic behaviors for diene copolymerization

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合成橡胶工业 2024年第4期47卷 348-348页

作者： FAN Xun-zhang ZHAO Yuan-jin LUO Shu-fang HE Ai-hua Shandong Provincial Key Laboratory of Olefin Catalysis and Polymerization/Key Laboratory of Rubber-Plastics of Ministry of Education/School of Polymer Science and Engineering Qingdao University of Science and TechnologyQingdao 266042China

Heterogeneous TiCl4/MgCl_(2) type Ziegler-Natta(Z-N)catalysts with unique advantages like low cost,high activity,high stereoregularity and pretty particle morphology,contribute to more than 130 Mt polyolefin large-scale ***,most researches related with heterogeneous Z-N catalysts focused onα-olefin polymerizations like ethylene,propylene,etc.

关键词： catalysts regularity propylene

Sub-nanometer Pt_(2)In_(3) intermetallics as ultra-stable catalyst for propane dehydrogenation

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能源化学:英文版 2023年第8期83卷 304-312,I0009页

作者： Yanan Xing Guiyue Bi Xiaoli Pan Qike Jiang Yuanlong Tan Yang Su Leilei Kang Bonan Li Lin Li Aiqin Wang Jingyuan Ma Xiaofeng Yang Xiao Yan Liu Tao Zhang CAS Key Laboratory of Science and Technology on Applied Catalysis ichEMDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China

Pt-based catalysts are the typical industrial catalysts for propane dehydrogenation(PDH),which still suffer from insufficient lo ng-term durability due to the structu ral instability and coke deposition.A commercial γ-Al_(2)O_(3) supported thermally robust sub-nanometer Pt2In3intermetallic catalyst with atomically ordered structure and rigorously separated Pt single atoms was fabricated,which showed outstanding robustness in 240 h long-term operation at 600℃ with the deactivation rate constant kdas low as0.00078 h^(-1), ranking among the lowest reported *** on various in situ characterizations and theoretical calculations,it was proved that the catalyst stability not only resulted from the separated Pt single-atom sites but also significantly affected by the distance of adjacent Pt *** increasing distance to 3.25 A in the Pt_(2)In_(3)could induce a weak π-adsorption configuration of propylene on Pt sites,which facilitated the desorption of propylene and restrained the side reactions like coking.

关键词： Propane dehydrogenation propylene Pt-In catalyst Intermetallic compounds Pt_(2)ln_(3)

Modeling-based optimization of a fixed-bed industrial reactor for oxidative dehydrogenation of propane

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Chinese Journal of Chemical Engineering 2016年第5期24卷 612-622页

作者： Ali Darvishi Razieh Davand Farhad Khorasheh Moslem Fattahi Department of Chemical and Petroleum Engineering Shiraz UniversityShirazIran Department of Chemical and Petroleum Engineering Sharif University of TechnologyAzadi AvenueTehranIran Department of Chemical Engineering Abadan Faculty of Petroleum Engineering Petroleum University of TechnologyAbadanIran

An industrial scale propylene production via oxidative dehydrogenation of propane （ODHP） in multi-tubular re- actors was modeled. Multi-tubular fixed-bed reactor used for ODHP process, employing 10000 of small diameter tubes immersed in a shell through a proper coolant flows. Herein, a theory-based pseudo-homogeneous model to describe the operation of a fixed bed reactor for the ODHP to correspondence olefln over V2O5/γ-Al203 catalyst was presented. Steady state one dimensional model has been developed to identify the operation parameters and to describe the propane and oxygen conversions, gas process and coolant temperatures, as well as other pa- rameters affecting the reactor performance such as pressure. Furthermore, the applied model showed that a double-bed multitubular reactor with intermediate air injection scheme was superior to a single-bed design due to the increasing of propylene selectivity while operating under lower oxygen partial pressures resulting in propane conversion of about 37.3%. The optimized length of the reactor needed to reach 100% conversion of the oxygen was theoretically determined. For the single-bed reactor the optimized length of 11.96 m including 0.5 m of inert section at the entrance region and for the double-bed reactor design the optimized lengths of 5.72 m for the first and 7.32 m for the second reactor were calculated. Ultimately, the use of a distributed oxygen feed with limited number of injection points indicated a significant improvement on the reactor performance in terms of propane conversion and propylene selectivity. Besides, this concept could overcome the reactor run- away temperature problem and enabled operations at the wider range of conditions to obtain enhanced propyl- ene production in an industrial scale reactor.

关键词： Fixed-bed reactor Mathematical modeling Oxidative dehydrogenation of propane propylene V2O5/γ-Al203 catalyst Optimization

CrOx supported on high-silica HZSM-5 for propane dehydrogenation

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Journal of Energy Chemistry 2020年第8期29卷 225-233,I0008页

作者： Zhong-Pan Hu Yansu Wang Dandan Yang Zhong-Yong Yuan National Institute for Advanced Materials School of Materials Science and EngineeringNankai UniversityTianjin 300350China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education).Nankai University Tianjin 300071China

Industrial propane dehydrogenation(PDH)catalysts generally suffer from low catalytic stability due to the coke formation onto the catalyst surface to cover the active *** exploitation of an efficient catalyst with both high catalytic selectivity and long-term stability toward PDH is of great importance but challenging to *** CrOx supported on high-silica HZSM-5 with a SiO2/Al2O3 ratio of 260(Cr/Z-5(260)is synthesized by a simple wet impregnation method,which exhibits high catalytic activity,good selectivity and excellent stability for *** a weight hourly space velocity(WHSV)of 0.59 h-1,a propylene formation rate of 4.1 mmol g-1cath-1(~32.6% propane conversion and ~94.2% propylene selectivity)can be maintained over the 5%Cr/Z-5(260)catalyst after 50 h time on stream,which is much better than commercial Cr/Al2O3(Catofin process,catalyst life is several hours)at the same reaction *** increasing the WHSV to 5.9 h-1,a high propylene formation rate of 27.9 mmol gcat-1h-1can be obtained over the 5%Cr/Z-5(260)catalyst after 50 h time on stream,demonstrating a very promising PDH *** results and Na+doping experiments reveal that the Cr species combined with Br?nsted acid sites in Cr/HZSM-5 catalysts are responsible for the high catalytic *** particular,the Br?nsted acid sites in HZSM-5 zeolite could increase the propane adsorption and enhance the C–H bond ***,the high surface area and well-defined pores of HZSM-5 zeolite can provide a special environment for the dispersion and stabilization of Cr species,thus guaranteeing high catalytic activity and stability.

关键词： Propane dehydrogenation ZSM-5 zeolite Chromium oxide propylene BrΦnsted acid sites