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Journal of Energy Chemistry 2014年第2期23卷 164-170页

作者： Bo Jiang Hongwei Cheng Longfei Luo Xionggang Lu Naijun Zhang Jizhong Liu Shanghai Key Laboratory of Modern Metallurgy and Materials Processing Shanghai University

***0.225Ta0.07503-δ （BRCFT, R = Ca, La or Sr） membranes were synthesized by a solid-state reaction. Metal cation Ca2＋, La3＋ or Sr2＋ doping on A-site partially substituted Ba2＋ in ***0.225Ta0.07503-δ oxides, and its subsequent effects on phase structure stability, oxygen permeability and oxygen desorption were systematically investigated by XRD, TG-DSC, Hz-TPR, O2-TPD techniques and oxygen permeation experiments. The partial substitution with Ca2＋, La3＋ or Sr2＋, whose ionic radii are smaller than that of Ba2＋, succeeded in stabilizing the cubic perovskite structure without formation of impurity phases, as revealed by XRD analysis. oxygen-involving experi- ments showed that BRCFT with A-site fully occupied by Ba2＋ exhibited good oxygen permeation flux under He flow, reaching about 2.3 ***-l .cm-2 at 900 with I mm thickness. Of all the membranes, BLCFT membrane showed better chemical stability in CO2, owing to the reduction in alkalinity of the mixed conductor oxide by La doping. In addition, we also found the stability of the perovskite structure under reducing atmospheres was strengthened by increasing the size of A-site cation （Ba2＋〉La3＋〉SrZ＋〉Ca2＋）.

关键词： perovskite phase stability oxygen permeation A-site substituted

oxygen permeation and Stability of Ce_(0.8)Gd_(0.2)O_(2-δ)-PrBaCo_(2-x)FexO_(5+δ) Dual-phase Composite Membranes

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Journal of Materials Science & Technology 2014年第12期30卷 1174-1180页

作者： Bo Jiang Hongwei Cheng Longfei Luo Xionggang Lu Zhongfu Zhou Shanghai Key Laboratory of Modern Metallurgy and Materials Processing School of Materials Science and EngineeringShanghai University

Dual-phase membranes of 60 wt% Ce0.8Gd0.2O2-δ-40 wt% Pr Ba Co2exFexO3 d（0 x 2） were prepared by a combined citrate and ethylene diamine tetraacetic acid（EDTA） complexing method. X-ray diffraction（XRD）results revealed the good chemical compatibility between ion-conducting phase CGO and electron-conducting phases PBC2 xFxO after sintering in air. The Fe ionic dopant had a significant effect on the phase structure stability and oxygen permeability under CO2 atmosphere, which was confirmed by XRD, thermogravimetrye differential scanning calorimetry（TGeD SC）, scanning electron microscopy（SEM） and oxygen permeation experiments. CGOeP BC0.5F1.5O dual-phase membrane demonstrated a stable oxygen permeation flux of2.71x10-7mol cm 2s 1with 50 mol% He/CO2 as the sweep gas at 925 C, and this value was much higher than that of perovskite-type membranes. The rate-limiting step in the oxygen permeation process changed from the bulk diffusion to the surface oxygen exchange when the CGOeP BC0.5F1.5O membrane thickness decreased to 0.8 mm or less. Due to the high oxygen permeation fluxes and the excellent structural stability under CO2 atmosphere, the CGOeP BC0.5F1.5O membrane is a great potential candidate material for separating oxygen from air in the oxy-fuel combustion techniques.

关键词： Dual-phase membrane Phase stability oxygen permeation CO2-tolerance

oxygen permeation Behaviors and Hardening Effect of Titanium Alloys at High Temperature

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Journal of Materials Science & Technology 2004年第6期20卷 719-723页

作者： Hongyan MA, Maocai WANG and Weitao WUState Key Laboratory for Corrosion and Protection, Institute of Metai Research, Chinese Academy of Sciences, Shenyang 110016, ChinaGraduate School of the Chinese Academy of Sciences, Beijing 100039, China Lab. for Corrosion and Protection Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China Graduate Sch. Chinese Acad. of Sci. Beijing 100039 China

In order to improve the surface hardness and wear resistance of Ti and Ti alloy components, an oxygen permeation treatment (OPT) was developed. The oxygen permeation behaviors of three Ti alloys, TA2, TB5 and TC11, treated in air with O-P medium at high temperature have been studied. The results show that the 0-P treatment can significantly improve the surface hardness of Ti alloys. The oxidation mass-gain of β-Ti alloy (TB5) is much higher than α-Ti alloy (TA2) under the same condition, while α+β Ti alloy (TC11) is the lowest. All the Ti alloys treated at this condition produce two surface layers: the outer layer consists mainly of TiO2, as well as trace of other oxides, and the inner layer consists of a Ti-O interstitial solid solution formed by the diffusion of oxygen in α crystal lattice. Thick scales of β Ti alloy (TB5) are easily formed depending mainly on the poor solid solution content of oxygen, while deep solution layer can be formed since partial β phase has been transformed into α phase. The scales of α-β Ti alloy (TC11) are very thin and compact. Aluminum-rich zone, as well as deficient zone, is found in oxide layers. A crystallographic characterization of oxygen solution layer has been performed and evaluated by crystallographic lattice constant.

关键词： Microstructure oxygen permeation Titanium Solid solution

Preparation and oxygen permeation properties of SrFe(Cu)O_(3-δ) dense ceramic membranes

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Journal of Natural Gas Chemistry 2009年第1期18卷 45-49页

作者： Heng Zhang Tingting Wang Xinfa Dong Weiming Lin School of Chemistry and Chemical Engineering Qufu Normal University Qufu 273165 Shandong China School of Chemical and Energy Engineering South China University of Technology Guangzhou 510640 Guangdong China

Mixed oxygen-ionic and electronic conducting membranes of SrFe（Cu）O3-δ were prepared by solid-state reaction method. The crystal structure, oxygen nonstoichiometry, and phase stability of the materials were studied by TGA and XRD. oxygen permeation fluxes through these membranes were studied at operating temperature ranging from 750 to 950 ℃. Results showed that doping Cu in SrFeO3-δ compound had a significant effect on the formation of single-phased perovskite structure. For SrFe1-xCu2O3-δ series materials, the oxygen nonstoichiometry and the oxygen permeation flux increased considerably with the increase of Cu-doping content （x = 0.1-0.3）. The sintering property of the membrane decreased significantly when the Cu substitution amount reached 40%. SrFe0.7Cu0.3O3-δ showed high oxygen permeation flux, but SrCuO2 and Sr2Fe2O5 phases formed in the compound after oxygen permeation test induced cracks in the membrane.

关键词： perovskite mixed conductor oxygen permeation phase stability

Preparation and characterization of Ce_(0.8)Sm_(0.2)O_(1.9)-La_(0.8)Sr_(0.2)Cr_(0.5)Fe_(0.5)O_(3-δ) dual-phase membranes for oxygen permeation

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Journal of Materiomics 2020年第1期6卷 224-231页

作者： Guangjun Zhang Xiaonan Bao Fanrong Zeng Nguyen Q.Minh Shaorong Wang School of Chemical Engineering and Technology China University of Mining and Technology1st Da-xue RoadXuzhouJiangsu221116China Jiangsu Province Engineering Laboratory of High Efficient Energy Storage Technology and Equipments 1st Da-xue RoadXuzhouJiangsu221116China University of California San Diego9500 Gilman Drive La JollaCA92093-0147USA

In this study,with La_(0.8)Sr_(0.2)Cr_(0.5)Fe_(0.5)O_(3-δ)(LSCrF)and Ce_(0.8)Sm_(0.2)O_(1.9)(SDC)taken as the electronic conducting phase and the oxide ion conductor,respectively,dual-phase composite ceramic membranes with or without 3%(in mole)Y_(2)O_(3) stable ZrO_(2)(3YSZ)support were prepared and tested as oxygen separation ***,the oxygen transmission performance was tested by the electrochemical method based on the limiting *** results obtained with this method coincide with those acquired by means of gas ***,the dependences of oxygen permeation rate on oxygen partial pressure,temperature and ceramic membrane thickness were *** air was used as the sweeping gas on the porous 3YSZ supported SDC-LSCrF dual-phase membrane,the oxygen permeation rate can reach 0.73,0.82,0.90 and 0.97 mL cm^(-2) min^(-1) at 650,700,750 and 800℃,respectively.

关键词： Dual-phase Ceramic membranes oxygen permeation Limiting current

Advancing oxygen separation:insights from experimental and computational analysis of La_(0.7)Ca_(0.3)Co_(0.3)Fe_(0.6)M_(0.1)O_(3-δ)(M=Cu,Zn)oxygen transport membranes

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Frontiers of Chemical Science and Engineering 2024年第6期18卷 17-29页

作者： Guoxing Chen Wenmei Liu Marc Widenmeyer Xiao Yu Zhijun Zhao Songhak Yoon Ruijuan Yan Wenjie Xie Armin Feldhoff Gert Homm Emanuel Ionescu Maria Fyta Anke Weidenkaff Fraunhofer Research Institution for Materials Recycling and Resource Strategies IWKS Alzenau 63755Germany Electrochemistry Laboratory Paul Scherrer InstituteVilligen PSI 5232Switzerland Department of Materials and Earth Sciences Materials and ResourcesTechnical University of DarmstadtDarmstadt 64287Germany Institute of Physical Chemistry and Electrochemistry Leibniz University HannoverHannover 30167Germany Institute for Computational Physics University of StuttgartStuttgart 70569Germany Computational Biotechnology RWTH AachenAachen 52074Germany

In this study,perovskite-type La_(0.7)Ca_(0.3)Co_(0.3)Fe_(0.6)M_(0.1)O_(3-δ)(M=Cu,Zn)powders were synthesized using a scalable reverse co-precipitation method,presenting them as novel materials for oxygen transport *** comprehensive study covered various aspects including oxygen permeability,crystal structure,conductivity,morphology,CO_(2) tolerance,and long-term regenerative durability with a focus on phase structure and *** membrane La_(0.7)Ca_(0.3)Co_(0.3)Fe_(0.6)M_(0.1)O_(3-δ)exhibited high oxygen permeation fluxes,reaching up to 0.88 and 0.64 mL·min^(−1)·cm^(−2) under air/He and air/CO_(2) gradients at 1173 K,*** 1600 h of CO_(2) exposure,the perovskite structure remained intact,showcasing superior CO_(2) resistance.A combination of first principles simulations and experimental measurements was employed to deepen the understanding of Cu/Zn substitution effects on the structure,oxygen vacancy formation,and transport behavior of the *** findings underscore the potential of this highly CO_(2)-tolerant membrane for applications in high-temperature oxygen *** enhanced insights into the oxygen transport mechanism contribute to the advancement of next-generation membrane materials.

关键词： perovskite oxygen permeation membrane oxygennionsdiffusiono xygen vacancy formation energy energy barrier

Electrifying Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ) for focalized heating in oxygen transport membranes

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Journal of Energy Chemistry 2024年第4期91卷 99-110页

作者： Marwan Laqdiem Julio García-Fayos Laura Almar Alfonso J.Carrillo Álvaro Represa JoséM.López Nieto Sonia Escolástico David Catalán-Martinez Jose M.Serra Instituto de Tecnología Química(Universitat Politècnica de València–Consejo Superior de Investigaciones Científicas) Av.Los Naranjos s/nE-46022 ValenciaSpain

Industry decarbonization requires the development of highly efficient and flexible technologies relying on renewable energy resources,especially biomass and solar/wind *** the case of pure oxygen production,oxygen transport membranes(OTMs)appear as an alternative technology for the cryogenic distillation of air,the industrially-established process of producing ***,OTMs could provide oxygen from different sources(air,water,CO_(2),etc.),and they are more flexible in adapting to current processes,producing oxygen at 700^(-1)000℃.Furthermore,OTMs can be integrated into catalytic membrane reactors,providing new pathways for different *** first part of this study was focused on electrification on a traditional OTM material(Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ)),imposing different electric currents/voltages along a capillary *** to the emerging Joule effect,the membrane-surface temperature and the associated O_(2) permeation flux could be ***,the OTM is electrically and locally heated and reaches 900℃on the surface,whereas the surrounding of the membrane was maintained at 650℃.The O_(2)permeation flux reached for the electrified membranes was~3.7 NmL min^(-1)cm^(-2),corresponding to the flux obtained with an OTM non-electrified at 900℃.The influence of depositing a porous Ce_(0.8)Tb_(0.2)O_(2-δ) catalytic/protective layer on the outer membrane surface revealed that lower surface temperatures(830℃)were detected at the same imposed electric ***,the electrification concept was demonstrated in a catalytic membrane reactor(CMR)where the oxidative dehydrogenation of ethane(ODHE)was carried *** reaction is very sensitive to temperature,and here,we demonstrate an improvement of the ethylene yield by reaching moderate temperatures in the reaction chamber while the O_(2) injection into the reaction can be easily fine-tuned.

关键词： oxygen permeation Oxidative dehydrogenation of ethane oxygen transport membranes Joule effect Mixed ionic-electronic conductors Catalytic membrane reactors

Perovskite-type oxygen-permeable membrane BaCo_(0.7)Fe_(0.2)Nb_(0.1)O_(3-δ) for partial oxidation of methane in coke oven gas to hydrogen

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Rare Metals 2010年第3期29卷 231-237页

作者： ZHANG Yuwen LIU Jiao LIU Yong DING Weizhong LU Xionggang Shanghai Key Laboratory of Modern Metallurgy ＆ Materials Processing Shanghai University Shanghai 200072 China

Perovskite-type oxygen-permeable membrane reactors of BaCo0.7Fe0.2Nb0.1O3-δ （BCFNO） packed with Ru-based catalyst had high oxygen permeability and could be used for hydrogen production by partial oxidation of methane in coke oven gas （COG）. At 1173 K, 94% of methane conversion, 85% of H2 selectivity, 107% of CO selectivity, and as high as 15.4 mL·cm^-2·min^-1 of oxygen permeation flux were obtained. The BCFNO membrane itself had poor catalytic activity to partial oxidation of CH4 in COG. During continuous operation for 70 h at 1173 K, no degradation of the membrane reaction performance was observed. XRD and SEM characterization also demonstrated that the BCFNO membrane reactor exhibited good stability in partial oxidation of methane in COG.

关键词： hydrogen production coke oven gas methane conversion oxygen permeation oxygen-permeable membrane

Microstructure evolution and oxidation states of Co in perovskite-type oxide Ba_(1.0)Co_(0.7)Fe_(0.2)Nb_(0.1)O_(3-δ) annealed in CO_2 atmosphere

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Journal of Energy Chemistry 2014年第5期23卷 575-581页

作者： Chengzhang Wu He Wang Xingxing Zhang Yuwen Zhang Weizhong Ding Chenghua Sun Shanghai Key Laboratory of Modern Metallurgy and Materials Processing Shanghai University School of Chemistry Monash University Clayton VIC 3800 Australia

Ba1.0Co0.7Fe0.2Nb0.1O3-γ（BCFN） oxide with perovskite cubic structure was synthesized by solid state reaction method. COa corrosion of BCFN membrane was investigated by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, diffuse reflectance infrared Fourier- transformed spectroscopy （DRIFT） and X-ray absorption fine structure spectroscopy （XAFS）. Cobalt （Co） K-edge absorption spectra of BCFN annealed in COa reveal that the oxidation states of Co in all the samples were larger than ＋3 and they decreased with the increase of calcination time. At 800 ℃, 1% CO2 introduced into He could speed up the reduction of Co cations in comparison with pure He. In addition, sulfate ions in the bulk of BCFN membrane preferred to migrate to the surface under CO2 calcination and form monoclinic Ba（CO3）0.9（SO4）0.1 besides orthorhombic witherite. Moreover, SEM results indicate that the nucleation and growth of carbonates grains started at the grain boundary of the membrane.

关键词： perovskite oxygen permeation carbon dioxide corrosion sulfate

Preparation and Characterization of Single-Phase Perovskite La_(0.6)Sr_(0.4)Co_(0.8)Fe_(0.2)O_(3-δ)

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Journal of Natural Gas Chemistry 2006年第1期15卷 58-62页

作者： Wenhui Yuan Xiaofang Hu Li Li College of Chemical Engineering and Energy South China University of Technology Guangdong Key Laboratory of Green Chemicals Guangzhou 510640 China

Single-phase perovskite La0.6Sr0.4Co0.8Fe0.2O3-δ has been successfully prepared by using citrate-EDTA complexation method at relatively low calcination temperature. The structure and thermal decomposition process of the complex precursor have been investigated by means of differential scanning calorimetry-thermal gravimetric analysis （DSC/TGA）, X-ray diffraction （XRD）, and Fourier transform infrared spectroscopic （FT-IR） measurements. The precursor decomposed completely and started to form perovskite-type oxide above 420 ℃ according to the differential scanning calorimetry （DSC） and thermal gravimetric analysis （TGA） results. Single-phase perovskite La0.6Sr0.4Co0.8Fe0.2O3-δ obtained has been confirmed from the XRD pattern, and no peak of SrCO3 was found by XRD of the oxides synthesized at a relatively low temperature of 800℃. The reducibility of La0.6Sr0.4Co0.8Fe0.2O3-δ was also characterized by the temperature programmed reduction （TPR） technique. Disk shaped dense La0.6Sr0.4Co0.8Fe0.2O3-δ membrane was prepared by the isostatical pressing method. The oxygen flux rate of dense La0.6Sr0.4Co0.8Fe0.2O3-δ membrane was （2.8-18）× 10^-8 mol/（cm^2.s） in the temperature range of 800-1000 ℃.

关键词： perovskite La0.6Sr0.4Co0.8Fe0.2O3-δ oxygen permeation preparation characterization