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Effect of vacuum impregnation on the performance of Co/SiO_2 Fischer-Tropsch catalyst

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Journal of Natural Gas Chemistry 2011年第4期20卷 350-355页

作者： Xiaofeng Zhou Qingling Chen Yuewu Tao Huixin Weng research Center of Petroleum Processing East China University of Science and Technology Shanghai 200237 China shanghai research institute of petrochemical technology SINOPEC Shanghai 201208 China

Two silica-supported cobalt catalysts were prepared by incipient wetness impregnation under atmospheric and vacuum conditions.N2 ph- ysisorption,H2 chemisorption,XRD,SEM,TEM,XPS and H2-TPR were used to characterize the *** results showed that the impregnation methods had an effect on the size,dispersion and reducibility of cobalt *** vacuum conditions,cobalt-containing steeping liquor could penetrate into the inner pores of silica support and more bivalent cobalt oxides were formed in the Co3O4 ***,cobalt precursors were rarely inclined to agglomerate and the smaller cobalt particles were uniform on the support,which led to the higher activity of the Co/SiO2（B）catalyst than the normal one under the reaction conditions of 483- 523 K,1 - 2 MPa,gas hourly space velocity of 500–1000 h-1 and molar ratio of H2/CO=0.5 - 2.0.

关键词： Fischer-Tropsch synthesis cobalt catalysts silica vacuum impregnation

Dehydrogenation of Isobutane to Isobutene with Carbon Dioxide over SBA-15-Supported Chromia-Ceria Catalysts

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Chinese Journal of Chemistry 2017年第10期35卷 1619-1626页

作者： Chunling Wei Fangqi Xue Changxi Miao Yinghong Yue Weimin Yang Weiming Hua Zi Gao shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of Chemistry Fudan University Shanghai 200433 China shanghai research institute of petrochemical technology SINOPEC Shanghai 201208 China

A series of SBA-15-supported chromia-ceria catalysts with 3% Cr and 1%--5% Ce （3Cr-Ce/SBA） were pre- pared using an incipient wetness impregnation method. The catalysts were characterized by XRD, N2 adsorption, SEM, TEM-EDX, Raman spectroscopy, UV-vis spectroscopy, XPS and H2-TPR, and their catalytic performance for isobutane dehydrogenation with CO2 was tested. The addition of ceria to SBA-15-supported chromia improves the dispersion of chromium species. 3Cr-Ce/SBA catalysts are more active than SBA-15-supported chromia （3Cr/SBA）, which is due to a higher concentration of Cr^6＋ species present on the former catalysts. The 3Cr-3Ce/SBA catalyst shows the highest activity, which gives 35.4% isobutane conversion and 89.6% isobutene selectivity at 570℃ after 10 min of the reaction.

关键词： isobutane dehydrogenation carbon dioxide chromia-ceria SBA-15 supported catalyst

Study of radiation-induced leakage current between adjacent devices in a CMOS integrated circuit

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Journal of Semiconductors 2012年第6期33卷 37-42页

作者：丁李利郭红霞陈伟范如玉 Department of Engineering Physics Tsinghua University Northwest institute of Nuclear technology

Radiation-induced inter-device leakage is studied using an analytical model and TCAD simulation. There were some different opinions in understanding the process of defect build-up in trench oxide and parasitic leakage path turning on from earlier *** reanalyze this problem and make it beyond argument,every possible variable is considered using theoretical analysis,not just the change of electric field or oxide thickness independently. Among all possible inter-device leakage paths,parasitic structures with N-well as both drain and source are comparatively more sensitive to the total dose effect when a voltage discrepancy exists between the drain and source *** N-well regions are commonly connected to the same power supply,these kinds of structures will not be a problem in a real CMOS integrated *** speaking,conduction paths of inter-device leakage existing in a real integrated circuit and under real electrical circumstances are not very sensitive to the total ionizing dose effect.

关键词： Total ionizing dose effect inter-device leakage current CMOS IC

Dehydrogenation of Propane to Propylene in the Presence of CO2 over Steaming-treated HZSM-5 Supported ZnO

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Chinese Journal of Chemistry 2012年第4期30卷 929-934页

作者：张帆缪长喜乐英红华伟明高滋 Department of Chemistry and shanghai Key Laboratory of Molecular Catalysis and lnnovative Materials Fudan UniversityShanghai 200433China shanghai research institute of petrochemical technology Shanghai 201208China

Dehydrogenation of propane to propylene over zinc oxide catalysts supported on steaming-treated HZSM-5 in the presence of CO2 has been investigated. The highest catalytic performance can be achieved on the 5%ZnO/HZSM-5（650） catalyst with the HZSM-5 support steaming at 650 ~C, which allows the maximum propyl- ene yields of 29.7% and 20.3% at the initial and steady states, respectively, in the catalytic dehydrogenation of pro- pane at 600 ~C. The superior catalytic performance of this catalyst can be attributed to high dispersion of ZnO and appropriate Bronsted acidity of the HZSM-5（650） support. The catalytic stability is enhanced by the addition of CO2 to the feed gas due to the suppression of coke formation.

关键词： dehydrogenation supported catalysts ZnO steaming-treated HZSM-5 stability

Insights into Promoting Effect of Sm on Catalytic Performance of the CeO_(2)/Beta Catalyst in Direct Conversion of Bioethanol to Propylene

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Chemical research in Chinese Universities 2022年第6期38卷 1547-1552页

作者： JIN Huan XU Ding TIAN Chao YUE Yinghong HUA Weiming GAO Zi shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of ChemistryFudan UniversityShanghai200438P.R.China shanghai Customs technology Center of Inspection and Test Shanghai200120P.R.China

A series of Sm-doped CeO_(2)/Beta composite catalysts with various Sm/Ce atomic ratios(0.1–0.4) were prepared by an incipient impregnation method, followed by calcination at 650 ℃. They were characterized by X-ray diffraction(XRD), N2 adsorption, X-ray photoelectron spectroscopy(XPS), Raman, NH3-temperature programmed desorption(TPD) and CO_(2)-TPD. The incorporation of Sm into CeO_(2)/Beta increases obviously the propylene yield for the selective conversion of ethanol to propylene. The promoting effect of Sm on CeO_(2)/Beta can be attributed to two reasons. One is more acetone intermediates are generated on the Sm-doped catalysts due to the enhanced formation of oxygen vacancies. The other is the conversion of acetone intermediate to propylene is enhanced owing to weaker and fewer acid sites on the Sm-doped catalysts.

关键词： Bioethanol Renewable propylene Sm-CeO_(2)/Beta composite Sm doping

Liquid-phase a-Pinene Isomerization over Fe-doped Sulfated Zirconia Prepared by a Hydrothermal Treatment-assisted Process

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Chinese Journal of Chemistry 2011年第6期29卷 1095-1100页

作者： Liu, Jianfeng Zhao, Jie Miao, Changxi Yue, Yinghong Hua, Weiming Gao, Zi shanghai research institute of petrochemical technology Shanghai 201208 China shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of Chemistry Fudan University Shanghai 200433 China

A series of Fe-doped （0.5%--3%） sulfated zirconia have been prepared by a hydrothermal treatment-assisted process. Textural and structural characterizations of the as-synthesized materials were performed by means of N2 adsorption, X-ray diffraction, transmission electron microscopy, scanning electron microscopy and thermogravimetric analysis. Temperature-programmed desorption of ammonia was used to determine the acidity of the samples. The effects of Fe-doping on the structure, acidity and catalytic activity of sulfated zirconia for liquid-phase a-pinene isornerization were investigated. The incorporation of small amounts of Fe into sulfated zirconia results in the increase of sulfate content and the number of acid sites, which is responsible for the enhanced activity of Fe-doped catalysts in comparison with the undoped one. Meanwhile, hydrothermal treatment helps to improve the activity of the catalyst.

关键词： sulfated zirconia Fe-doping hydrothermal treatment promoting effect acidity isomerization

Isobutane Dehydrogenation Assisted by C02 over Silicalite-i-Supported ZnO Catalysts: Influence of Support Crystallite Size

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Chinese Journal of Chemistry 2020年第7期38卷 703-708页

作者： Yajun Luo Chunling Wei Changxi Miao Yinghong Yue Weiming Hua Zi Gao shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of ChemistryFudan UniversityShanghai 200438China shanghai research institute of petrochemical technology SINOPEC Shanghai 201208China

The ZnO catalysts supported on Silicalite-1 zeolites with different crystallite sizes(0.08,0.35,1 and 1.7 jjm,respectively)and 5%Zn were synthesized via an incipient wetness *** catalysts were characterized by XRD,N2 adsorption,SEM,TEM-EDX,DRIFT spectra and NH3-TPD,and their catalytic performance in isobutane dehydrogenation assisted by C02 was *** catalytic activity is strongly dependent on the crystallite size of Silicalite-1 *** ZnO/S-l-O.35 catalyst with ca.0.35 μmcrystallite size displays the highest activity,affording an initial isobutane conversion of 51.0%and 74.5%isobutene *** can be attributed to a higher amount of acid sites present on this catalyst as well as the largest amount of nest silanols possessed by the S-l-0.35 support.

关键词： method. crystallite catalyst

Oxidative Dehydrogenation of 1-Butene to 1,3-Butadiene Using CO2 over Cr-SiO2 Catalysts Prepared by Sol-gel Method

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Chemical research in Chinese Universities 2018年第4期34卷 609-615页

作者： GAO Biao LUO Yajun MIAO Changxi YUE Yinghong YANG Weimin HUA Weiming GAO Zi shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of Chemistry Fudan University Shanghai 200433 P. R. China shanghai research institute of PetrochemicaI technology SINOPEC Shanghai 201208 P. R. China

A series of Cr-SiO2 catalysts with a Cr content（mass fraction） ranging from 0.5% to 9% was prepared by a sol-gel method. The catalysts were characterized by XRD, N2 adsorption, EDX elemental mapping, Raman spectros- copy, UV-Vis spectroscopy, XPS and H2-TPR, and their catalytic behavior in the dehydrogenation of 1-butene to 1,3-butadiene（BD） using CO2 as a soft oxidant was studied. The initial BD yield is well correlated with the amount of Cr6~ in the fresh catalysts. The highest BD yield of ca. 34% is achieved on the catalysts with 5%--9% Cr at 600 ~C -1 -1 and weight hourly space velocity（WHSV） of 4.5 g＇geat＇h ~ The promoting effect of CO2 on the BD yield was ob- served, which can be attributed to the reaction coupling between a simple dehydrogenation of 1-butene and the re- verse water-gas shift reaction as well as regaining the oxidation state（lattice oxygen） of reduced Cr3＋ species due to the mild oxidation ability of CO2. The Cr-SiO2 catalyst exhibits higher BD yield than the Cr catalyst supported on SBA-15, which is attributed to the higher amount of Cr6＋ present on the former catalyst.

关键词： 1,3-Butadiene CO2 oxidative dehydrogenation Cr-based catalyst Sol-gel method

Catalytic performance of iron oxide loaded on electron-rich surfaces of carbon nitride

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Journal of Energy Chemistry 2016年第6期25卷 1021-1026页

作者： Zhen Dong Tao Wang Jie Zhao Teng Fu Li Wang Jinlin Li Weiping Ding Key Lab of Mesoscopic Chemistry School of Chemistry and Chemical Engineering Nanjing University Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission & Ministry of Education College of Chemistry and Materials Science South-Central University for Nationalities

Carbon nitride (CN) in CN encapsulated Ni/ Al2O3 (denoted as CN/Ni/Al2O3) catalyst was evidenced previously as a material in electron-rich state and possessed H-2-dissociative adsorption activity due to the electron doping effect from underlying nickel. In this report, iron oxide loaded on the CN/Ni/Al2O3 was synthesized and investigated by Fischer-Tropsch (F-T) synthesis to test the special effect of electron-rich support on the catalytic activity of iron oxide. The Fe/CN/Al2O3 and CN/Ni/Al2O3 samples were accordingly synthesized for comparison. In Fe/CN/Ni/Al2O3, the iron oxide was reduced to magnetite by syngas as evidenced by the in-situ XPS measurements and XRD pattern of used catalyst. Compared with Fe/CN/Al2O3, more light hydrocarbons over Fe/CN/Ni/Al2O3 were observed. It should be understood by the interaction between iron oxide and support mainly due to the effect of electron-rich state and thus enhanced H-2 adsorption ability. In addition, such a novel support facilitated the CO conversion and retarded the water-gas shift reaction and CO2 formation. The new type of adjustment on electronic state should be useful for novel catalyst design. (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： Electron-rich state Fischer-Tropsch synthesis Iron-based H-2-dissociation