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Cooperative catalytic effects between the penta-coordinated Al and Al_(2)O_(3)in Al_(2)O_(3)-AlPO_(4)for aldol condensation of methyl acetate with formaldehyde to methyl acrylate

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Chinese Journal of Chemical Engineering 2022年第12期52卷 172-183页

作者： Zhenyu Wu zengxi li Chunshan li School of Chemical Science University of Chinese Academy of SciencesBeijing 100049China Beijing Key Laboratory of Ionic liquids Clean Process Key Laboratory of Green Process and EngineeringKey Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China Zhongke Langfang Institute of Process EngineeringChinese Academic of SciencesHebei 065000China

The bare amorphous Al_(2)O_(3)-AlPO_(4)and Cs/Al_(2)O_(3)-AlPO_(4)catalysts were developed for the aldol condensation of methyl acetate with formaldehyde to methyl *** structure and property of catalyst were characterized by XRD,XPS,BET,Pyridine-IR,FT-IR,^(27)Al-MASNMR,NH_(3)-/CO_(2)-TPD and *** correlation between structural features and acid-base properties was established,and the loading effect of the cesium species was *** to cooperative catalytic effects between the penta-coordinated Al and Al_(2)O_(3),the weak-Ⅱacid and medium acid site densities and the product selectivity were *** the basic site densities of these catalysts were almost in proportion to the conversion of methyl *** loaded Cs could form new basic sites and change the distribution of acid sites which further enhance the catalytic *** a result,the 10Cs/8AlP was proved to be an optimal catalyst with the yield and selectivity of 21.2%and 85%for methyl acrylate *** the reaction,a deactivation behavior was observed on 10Cs/8AlP catalyst due to the carbon deposition,however,it could be regenerated by thermal treatment in the air atmosphere at 400℃.

关键词： Methyl acrylate(MA) Aldol condensation Al_(2)O_(3)-AlPO_(4) Penta-coordinated aluminum Cooperative effects

全民健身视域下民族武术套路运动的发展策略分析

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当代体育科技 2024年第4期14卷 102-104页

作者：李增曦陈雪莹韩国龙仁大学韩国京畿道龙仁市17092 韩国明知大学韩国京畿道龙仁市17058

该文旨在探讨全民健身视域下民族武术套路运动的发展策略,将全民健身政策与传统武术相结合,以促进全民身体素质的提高,推动传统文化的传承与创新。首先,在政策制定方面,强调制定专项政策,包括财政支持、场地政策和人才培养政策,以确保... 详细信息

该文旨在探讨全民健身视域下民族武术套路运动的发展策略,将全民健身政策与传统武术相结合,以促进全民身体素质的提高,推动传统文化的传承与创新。首先,在政策制定方面,强调制定专项政策,包括财政支持、场地政策和人才培养政策,以确保武术套路运动在全国范围内得到充分的政策支持。其次,在推广措施方面,提出通过全媒体宣传、社区体验课、学校合作等方式,将武术套路运动推广至更广泛的群体。通过这一全面而系统的发展策略分析,该文旨在为全民健身政策下的民族武术套路运动提供可行性和科学性的指导,以期促进传统武术的繁荣与创新,朝着全面建设中国体育强国的目标迈出坚实的一步。

关键词：全民健身民族武术武术套路民族传统体育

liquid-phase esterification of methacrylic acid with methanol catalyzed by cation-exchange resin in a fixed bed reactor:Experimental and kinetic studies

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Chinese Journal of Chemical Engineering 2023年第6期58卷 1-10页

作者： Junyang liu Luming Wang Yuhang Bian Chunshan li zengxi li Jie li School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China Beijing Key Laboratory of Ionic liquids Clean Process Key Laboratory of Green Process and EngineeringState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China Langfang Technological Center of Green Industry Langfang 065801China

The kinetic behavior of esterification between methacrylic acid and methanol catalyzed by NKC-9 resin was studied in a fixed bed *** reaction was conducted in the temperature range of 323.15 to 368.15 K with the molar ratio of reactants from 0.8 to 1.4 under certain *** measurement data were regression with the pseudo-homogeneous(P-H),Eley-Rideal(E-R),and Langmuir-Hinshelwood(L-H)heterogeneous kinetic *** adsorption experiments were implemented to gain the adsorption equilibrium constants of four *** the above three models,the L-H model exhibited the best fitting *** stability of NKC-9 was evaluated by long-term running with the yield of methyl methacrylate no decrease during 3000 h *** structure and physicochemical properties of the new and used catalyst were performed by several characterizations including thermogravimetric analysis(TG),scanning electron microscope(SEM),X-ray diffraction(XRD)and Fourier transform infrared spectroscopy(FT-IR)and so on.

关键词： Kinetics Esterification Methyl methacrylate Cation-exchange resin Fix bed reactor

A novel kind of multiple steady states characteristics in the dividing wall column

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Chinese Journal of Chemical Engineering 2019年第4期27卷 869-876页

作者： Erwei Song zengxi li Erqiang Wang School of Chemical Sciences University of Chinese Academy of Sciences

In this article, one kind of multiple steady states(MSS) phenomenon was investigated for a dividing wall column(DWC). The four-section model constructed in Aspen Plus was employed to simulate two DWC cases: mixture of n-hexane, n-heptane and n-octane;system of methanol, ethanol and n-propanol. It can be seen that there is a range of vapor split ratio in which multiple solutions of reflux ratio exist for fixed DWC configuration with the same feed and product streams. The width and the curve shapes of the MSS region, and the number of solutions change with the liquid split ratio. This MSS phenomenon was further explained using the component recovery around the prefractionator and the component recycling flow inside the DWC. This MSS phenomenon is helpful for DWC design by knowing the probable existence of multiple solutions in advance.

关键词： Dividing wall column Multiple steady states Vapor split ratio liquid split ratio Recycling flow

In-situ generated ionic liquid catalyzed aldol condensation of trioxane with ester in mild homogeneous system

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Green Energy & Environment 2019年第3期4卷 293-299页

作者： Gang Wang zengxi li Chunshan li Suojiang Zhang School of Chemical Sciences University of Chinese Academy of Sciences100049China Beijing Key Laboratory of Ionic liquids Clean Process State Key Laboratory of Multiphase Complex SystemsThe National Key Laboratory of Clean and Efficient Coking TechnologyInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China

α, β-unsaturated esters were often synthesized from aldehydes and esters in the presence of strong organic base that was very sensitive to air and moisture via aldol reaction. Trioxane was very useful C1 resource, however, the decomposition of it was always the challenging problem that facing researchers. Herein, a novel synthetic methodology for α, β-unsaturated ester preparation from trioxane and ester with mild catalysis of generated ammonium trifluoromethanesulfonate ionic liquid. The enolization of ester as well as the decomposition of trioxane could proceed easily in the presence of boryl trifluoromethanesulfonate and amine at 20–25℃. Then the enolate and decomposed formaldehyde occurs aldol reaction to form α, β-unsaturated ester. With this strategy, the yield and selectivity of product from various substrates including aliphatic esters,lactones and thioester could reach up to 85.2% and 90.1%.

关键词： α,β-unsaturated ester Trioxane Ionic liquid Aldol reaction Enolization

Ionic liquid catalyzed solvent-free synthesis of chalcone and its derivatives under mild conditions

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Chinese Journal of Chemical Engineering 2021年第5期34卷 160-166页

作者： Qiu Zhao Gang Wang Fuxia liao Yifan Sha Fei Xu Chunshan li zengxi li Yijun Cao School of Chemical Engineering and Energy Zhengzhou UniversityZhengzhou 450001China Key Laboratory of Green Process and Engineering State Key Laboratory of Multiphase Complex SystemsBeijing Key Laboratory of Ionic Liquids Clean ProcessInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China

An ionic liquid(IL)catalyzed solvent-free process was developed for the direct synthesis of chalcone and its derivatives by using substituted acetophenones and benzaldehydes via aldol reaction under mild conditions.A series of acidic and basic ILs were selected and *** influences of cations and reaction conditions on product yield and selectivity were systematically ***[Bmim]OH was identified as the optimal IL,with the highest yield and selectivity reaching up to 96.7% and 100%,respectively.A reaction mechanism-based kinetic model was established and regressed with experimental data,revealing the β-Hydroxylketone dehydrolysis with activation barrier of 37.8 kJ·mol^(-1) was observed as the ratecontrolling step.

关键词： Ionic liquid Chalcone Aldol reaction Kinetic model

Effect of SiO_(2)/Al_(2)O_(3)ratio on the conversion of methanol to olefins over molecular sieve catalysts

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Frontiers of Chemical Science and Engineering 2011年第1期5卷 79-88页

作者： Qian WANG Lei WANG Hui WANG zengxi li Xiangping ZHANG Suojiang ZHANG Kebin ZHOU Graduate University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Multiphase Complex System Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China

A series of SAPO-34 molecular sieves with different SiO_(2)/Al_(2)O_(3)ratios have been synthesized for the methanol-to-olefin(MTO)*** physico-chemical properties are characterized by various techniques such as X-ray diffraction(XRD),scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),Fourier transform infrared spectroscopy(FT-IR)and N2 *** results are compared with those of the commercial HZSM-5,which show that the crystallinity and particle diameter of SAPO-34 as well as HZSM-5 increase with SiO_(2)/Al_(2)O_(3)*** variation of BET surface area of SAPO-34 is different from that of HZSM-5 and the sample with SiO_(2)/Al_(2)O_(3)ratio of 0.4 exhibits the highest BET surface ***-IR spectra indicate that HZSM-5 has both Brǿnsted and Lewis acid sites and Brǿnsted acid sites are stronger,whereas SAPO-34 samples are dominated only by Lewis acid *** the SiO_(2)/Al_(2)O_(3)ratio increases,propylene and butylenes become the predominant product of the MTO reaction over *** contrast,the main products of this reaction catalyzed by SAPO-34 are ethylene and *** to the product distribution,the reaction mechanism over HZSM-5 catalysts is proposed.

关键词： HZSM-5 SAPO-34 methanol-to-olefin(MTO) SiO_(2)/Al_(2)O_(3)ratio

Leaching kinetics of fluorine during the aluminum removal from spent li-ion battery cathode materials

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Journal of Environmental Sciences 2024年第4期138卷 312-325页

作者： Shengjie li Jianxin Zhu Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

The high content of aluminum(Al)impurity in the recycled cathode powder seriously affects the extraction efficiency of Nickel,Cobalt,Manganese,and lithium resources and the actual commercial value of recycled materials,so Al removal is crucially important to conform to the industrial standard of spent li-ion battery cathode *** this work,we systematically investigated the leaching process and optimum conditions associated with Al removal from the cathode powder materials collected in a wet cathode-powder peeling and recycling production line of spent li-ion batteries(liBs).Moreover,we specifically studied the leaching of fluorine(F)synergistically happened along with the removal process of Al,which was not concerned about in other studies,but one of the key factors affecting pollution prevention in the recovery *** mechanism of the whole process including the leaching of Al and F from the cathode powder was indicated by using NMR,FTIR,and XPS,and a defluoridation process was preliminarily investigated in this *** leaching kinetics of Al could be successfully described by the shrinking core model,controlled by the diffusion process and the activation energy was 11.14 kJ/***,the leaching of F was attributed to the dissolution of liPF6and decomposition of PVDF,and the kinetics associated was described by Avrami *** interaction of Al and F is advantageous to realize the defluoridation to some *** is expected that our investigation will provide theoretical support for the large-scale recycling of spent liBs.

关键词： Al removal F leaching Cathode powder Heating alkali leaching Leaching kinetics

Additives strategies to improving cycling stability of li metal batteries by modifying electrode electrolyte interphases

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Progress in Natural Science:Materials International 2024年第2期34卷 338-344页

作者： Yuan li Pengfei Huang Chunyu Cui Xiaoyuan Ma li Chen Zekun li linhai li Yuhong Tian School of Biological and Chemical Engineering Guangxi University of Science and Technology School of College of Chemistry and Chemical Engineering Hunan University Isky Future Energy Institute

li metal batteries（LMBs） have attracted much attention due to the ultra-high theoretical capacity of the li metal anode（LMA）.However,the uncontrollable dendrites growth and low coulombic efficiency hinder their practical ***,we explore 3,5-difluoropyridine（2F-BD） as a novel electrolyte additive to enable highperformance *** 2F-BD additive participates in and modifies the solvation structure of li ions by reducing the coordinated number of PF6-at the electrode surface,leading to the formation of a liF and li3N-rich solid electrolyte interphase（SEI）.The liF component increases the robustness of SEI and suppresses the formation of li dendrites,while the li3N component facilitates the transportation and reaction kinetics of li *** a result,the li‖li symmetric cell presents a stable cycling performance of up to 500 h at a current density of 1 mA *** coupling with liFePO4cathode,the obtained full cell achieves high specific capacities of 106.06 mA h g-1and 84.98 mA h g-1at 2.55 mA cm-2and 5.10 mA cm-2,respectively,and maintains a high capacity retention of84.0% after 1000 cycles at 0.13 mA cm-2,with an average cycling CE of 99.58%.

关键词： Electrolyte additive li dendrites li metal batteries liF and li3N-Rich electrode-electrolyte interphase liFePO4 cathode