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Low-cost and fluoride-free synthesis of MFI zeolite nanosheets with enhanced stability for benzene alkylation with ethanol

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Journal of Energy Chemistry 2025年第1期 458-468页

作者： Peng Zhu Cun Liu Yiren Yu Guoshu Gao Yumeng Zhao Xiongfu Zhang Guodong Liu Guohui Yang State Key Laboratory of fine chemicals School of Chemical Engineering Dalian University of Technology State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFI zeolite nanosheets through a Silicalite-1(Sil-1) seed suspension and urea cooperative strategy, only with inexpensive colloidal silica as the Si source. Our approach was effective for synthesizing both Sil-1 and aluminum-containing ZSM-5 nanosheets. By optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where Sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented *** obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully carried out in a 3 L highpressure autoclave, yielding samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFI nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis.

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Study on Mechanism of Rare Earth PVC Stabilizer

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Journal of Rare Earths 2003年第3期21卷 328-330页

作者：彭振博胡斌苏庆德曲锦忠 Department of Chemistry University of Science and Technology of China Kehua institute of fine chemical Industry

Rare earth compounds can be used as PVC thermal stabilizers. According to the infrared spectra of the mixture of PVC and some stearates, the mechanism of stabilization of different stearates was studied. The specialty of rare earth stabilizers was found. They can change the conformation of PVC and restrain the elimination of HCl. From this aspect, the unique synergetic effect with other stabilizers of rare earth compounds can be explained.

关键词： organic chemistry PVC stabilizer infrared spectroscopy synergetic effect rare earths

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Wormholelike mesoporous carbon supported Pt Ru catalysts toward methanol electrooxidation

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Journal of Energy Chemistry 2017年第1期26卷 200-206页

作者： Weifeng Liu Xiaoping Qin Xiongfu Zhang Zhigang Shao Baolian Yi State Key Laboratory of fine chemicals School of Chemical Engineering Dalian University of Technology Dalian institute of chemical Physics Chinese Academy of Sciences

Wormholelike mesoporous carbons (WMCs) with three different pore diameters (D-P), namely WMC-F7 (D-p = 8.5 nm), WMC-F30 (D-p =4.4 nm), and WMC-F0 (D-p =3.1 nm) are prepared via a modified sol-gel process. Then PtRu nanoparticles with the particle size (40 of 3.2 nm supported on WMCs are synthesized with a modified pulse microwave-assisted polyol method. It is found that the pore diameter of WMCs plays an important role in the electrochemical activity of PtRu toward alcohol electrooxidation reaction. PtRu/WMC-F7 with D-p > 2d(pt) exhibits the largest electrochemical surface area (ESA) and the highest activity toward methanol electrooxidation. With the decrease in Dp, PtRu/WMC-F30 and PtRu/WMC-F0 have much lower ESA and electrochemical activity, especially for the isopropanol electrooxidation with a larger molecular size. When D-p is more than twice d(pt), the mass transfer of reactants and electrolyte are easier, and thus more PtRu nanoparticles can be utilized and the catalysts activity can be enhanced. (C) 2016 Science Press and Dalian institute of chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.

关键词： Wormholelike mesoporous carbon PtRu catalyst Pore diameter Methanol electrooxidation

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Different efficiency toward the biomimetic aerobic oxidation of benzyl alcohol in microchannel and bubble column reactors: Hydrodynamic characteristics and gas–liquid mass transfer

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Chinese Journal of chemical Engineering 2023年第3期55卷 84-92页

作者： Qi Han Xin-Yuan Zhang Hai-Bo Wu Xian-Tai Zhou Hong-Bing Ji fine chemical Industry Research institute School of Chemical Engineering and TechnologySun Yat-sen UniversityZhuhai 519082China fine chemical Industry Research institute School of ChemistrySun Yat-sen UniversityGuangzhou 510275China Huizhou Research institute Sun Yat-sen UniversityHuizhou 516081China

The selective aerobic oxidation of benzyl alcohol to benzaldehyde has attracted considerable attention because benzaldehyde is a high value-added product. The rate of this typical gas–liquid reaction is significantly affected by mass transfer. In this study, CoTPP-mediated(CoTPP: cobalt(II) mesotetraphenylporphyrin) selective benzyl alcohol oxidation with oxygen was conducted in a membrane microchannel(MMC) reactor and a bubble column(BC) reactor, respectively. We observed that 83% benzyl alcohol was converted within 6.5 min in the MMC reactor, but only less than 10% benzyl alcohol was converted in the BC reactor. Hydrodynamic characteristics and gas–liquid mass transfer performances were compared for the MMC and BC reactors. The MMC reactor was assumed to be a plug flow reactor,and the dimensionless variance was 0.29. Compared to the BC reactor, the gas–liquid mass transfer was intensified significantly in MMC reactor. It could be ascribed to the high gas holdup(2.9 times higher than that of BC reactor), liquid film mass transfer coefficient(8.2 times higher than that of BC reactor), and mass transfer coefficient per unit interfacial area(3.8 times higher than that of BC reactor). Moreover,the Hatta number for the MMC reactor reached up to 0.61, which was about 15 times higher than that of the BC reactor. The computational fluid dynamics calculations for mass fractions in both liquid and gas phases were consistent with the experimental data.

关键词： Membrane microchannel reactor Gas-liquid flow Mass transfer Benzyl alcohol Computational fluid dynamics(CFD) Bubble column reactor

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Zn–Ca–Al mixed oxide as efficient catalyst for synthesis of propylene carbonate from urea and 1,2-propylene glycol

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Chinese Journal of chemical Engineering 2017年第5期25卷 609-616页

作者： Sen Liu Suhong Sun Xuehui Tian Peiyong Sun Shenghong Zhang Zhilong Yao College of chemical Engineering Sichuan University Beijing Key Laboratory of Enze Biomass fine chemicals College of Chemical EngineeringBeijing Institute of Petrochemical Technology

A series of Zn–Ca–Al oxides with different CaO and ZnO contents have been prepared and evaluated in the synthesis of propylene carbonate(PC) from 1,2-propylene glycol(PG) and urea in a batch reactor. The effect of catalyst composition, basicity and reaction process parameters such as temperature, catalyst dose, molar ratio of PG to urea, purge gas flow and reaction time has been studied to find suitable reaction conditions for the PC synthesis. The PC selectivity and yield under the desired conditions could reach 98.4% and 90.8%, respectively. The best performing catalyst also exhibited a good reusability without appreciable loss in the PC selectivity and yield after five consecutive reaction runs. In addition, a stepwise reaction pathway involving a 2-hydroxypropyl carbamate intermediate was proposed for the urea alcoholysis to PC in the presence of Zn–Ca–Al catalysts, according to the time dependences of reaction intermediates and products.

关键词： Propylene carbonate 1 2-Propylene glycol Urea Catalysis Alcoholysis

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Preparation of mesoporous activated carbons from coal liquefaction residue for methane decomposition

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Journal of Natural Gas Chemistry 2012年第6期21卷 759-766页

作者： Jianbo Zhang Lijun Jin Shengwei Zhu Haoquan Hu State Key Laboratory of fine chemicals Institute of Coal Chemical EngineeringSchool of Chemical EngineeringDalian University of TechnologyDalian 116024LiaoningChina

Mesoporous activated carbons were prepared from direct coal liquefaction residue （CLR） by KOH activation method, and the experiments were carried out to investigate the effects of KOH/CLR ratio, solvent for mixing the CLR and KOH, and carbonization procedure on the resultant carbon texture and catalytic activity for catalytic methane decomposition （CMD）. The results showed that optimal KOH/CLR ratio of 2 ： 1; solvent with higher solubility to KOH or the CLR, and an appropriate carbonization procedure are conductive to improving the carbon pore structure and catalytic activity for CMD. The resultant mesoporous carbons show higher and more stable activity than microporous carbons. Additionally, the relationship between the carbon textural properties and the catalytic activity for CMD was also discussed.

关键词： mesoporous activated carbon KOH methane decomposition coal liquefaction residue hydrogen

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Liquid-phase epoxidation of propylene with molecular oxygen by chloride manganese meso-tetraphenylporphyrins

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Chinese Journal of chemical Engineering 2022年第8期35卷 61-65页

作者： Xian-Tai Zhou Ling-Ling Wang Yang Li Hong-Bing Ji fine chemical Industry Research institute School of Chemical Engineering and TechnologySun Yat-sen UniversityZhuhai 519082China fine chemical Industry Research institute School of ChemistrySun Yat-sen UniversityGuangzhou 510275China School of chemical Engineering Guangdong University of Petrochemical TechnologyMaoming 525000China

Propylene molecule owns two active sites,the direct epoxidation of propylene by dioxygen is still a challenge due to the limitation of *** this work,the direct liquid-phase propylene aerobic epoxidation protocol by chloride manganese meso-tetraphenylporphyrin(MnTPPCl)was *** conversion of propylene was 12.7%,and the selectivity towards PO(propylene oxide)reached up to 80.5%.The formation of PO was attributed to the mechanism via high-valent Mn species,which was confirmed by means of in situ UV–vis spectrum.

关键词： Propylene Epoxidation Dioxygen Manganese porphyrins Liquid phase

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Advances and perspectives in catalytic oxidation of hydrocarbons in liquid phase

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Progress in Natural Science:Materials International 2007年第9期17卷 1003-1011页

作者： Zhou Lipeng,Yang Guanyu,Zhang Wei,Sun Zhiqiang,Gao Jin,Miao Hong,Chen Chen,Ma Hong,Li Xiaoqiang,Zhang Qiaohong,Wang Feng,Tong Xinli and Xu Jie(Laboratory of fine chemicals,Dalian institute of chemical Physics,Chinese Academy of Sciences,Dalian 116023,China) Laboratory of fine chemicals， Dalian institute of chemical Physics， Chinese Academy of Sciences， Dalian 116023， China

This review article summarizes recent advances in catalytic oxidation of hydrocarbons,especially presents two strategies for activation of C-H bonds or molecular *** on our own research results,the applications of the two methods in the oxidation of cyclohexane,toluene and ethyl benzene,*** introduced,and the perspectives of the two methods are also discussed.

关键词： hydrocarbon oxidation molecular oxygen catalysis C-H bond

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Modified disordered carbon prepared from 3,4,9,10-perylenetetracarboxylic dianhydride as an anode material for Li-ion batteries

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International Journal of Minerals,Metallurgy and Materials 2015年第2期22卷 203-209页

作者： Fei-biao Chen Bo-rong Wu Yun-kui Xiong Wei-lin Liao Dao-Bin Mu Feng Wu Beijing Key Laboratory of Environmental Science and Engineering School of Chemical Engineering and Environment Beijing Institute of Technology Jiangxi fine chemical Key Laboratory Jiangxi Normal University

To prepare an anode material for Li-ion batteries with high discharge capacity and good cycling stability, disordered carbon （DC） formed by calcinations of 3,4,9,10-perylenetetracarboxylic dianhydride was modified via an acid treatment using a mixture of HNO3 and H2SO4. The modified disordered carbon （MDC） was characterized by Fourier-transform infrared （FTIR） spectroscopy, X-ray diffraction （XRD） analysis, Brtmaner-Emmett-Teller （BET） analysis, and scanning electron microscopy （SEM）. FTIR spectra confirm the successful introduction of carbonyl groups onto the DC surface. Some pores appear in the columnar structure of MDC, as observed in SEM micro- graphs. Li＋ ions intercalation/deintercalation is facilitated by the modified morphology. Electrochemical tests show that the MDC exhibits a significant improvement in discharge capacity and cycling stability. These results indicate that the MDC has strong potential for use as an anode material in Li-ion batteries.

关键词： carbon perylenetetracarboxylic dianhydride anode materials lithium-ion batteries

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Synthesis and photoelectric properties of an organic dye containing benzo[l,2-b:4,5-b']dithiophene for dye-sensitized solar cells

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Chinese chemical Letters 2013年第2期24卷 149-152页

作者： Yu-Rong Gao Ling-Ling Chu Wei Guo Ting-Li Ma Dalian Research and Design institute of chemical Industry State Key Laboratory of fine chemicals School of Chemical EngineeringDalian University of Technology

Received 7 September 2012 Received in revised form 27 November 2012 Accepted 11 December 2012 Available online 4 February 2013

关键词： DyesSolar cellsBenzodithiophenePower conversion efficiency

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