SONIA REGINA HOMEM DE MELLO CASTANHO

SONIA REGINA HOMEM DE MELLO CASTANHO

(Fonte: Lattes)

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Graduada em Engenharia de Materiais (UFSCar, Universidade Federal de São Carlos), Mestre em Tecnologia Nuclear (IPEN/USP, Universidade de São Paulo) e Doutora em Ciências Químicas-Cerâmicos (UAM/ES -ICV/CSIC, Universidad Autónoma de Madrid, Espanha e Instituto de Ceramica y Vidrio/CSIC de Espanha). Ela é Pesquisadora Senior e atualmente Gestora Adjunta em Pesquisa e Desenvolvimento do Centro de Ciências e Tecnologia de Materiais (CCTM) do Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP). É Professora da Universidade de São Paulo (USP), no programa de posgraduação Tecnologia Nuclear - Materiais. Coordenadora do grupo de pesquisas (GP/CNPq) em Materiais e Meio Ambiente. Principais áreas de atuação: - Energias Renováveis (células a combustível, catalizadores e biomassa), - Ambiental (mitigação, inertização e requalificação de efluentes e subprodutos de processos extrativistas e industriais, diretivas ambientais (RhOS, WEEE)), - Cerâmicas Biocompatíveis (vidros, compósitos multifuncionais para a implantologia). Experiência em gestão de Centro de Pesquisas, gestão ambiental, gestão de projetos, planejamento composicional de materiais, processamento coloidal, reologia, vidros e vitroceramicos, compósitos multifuncionais e nanoestruturas naturais. (Texto extraído do Currículo Lattes em 27 dez. 2021)

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Use of waste water glass as silica supplier in synthesis of pure and Mg-doped lanthanum silicate powders for IT-SOFC application
2019 - YAMAGATA, C.; LEME, D.R.; CASTANHO, S.R.H.M.
Water glass in alkali solution (Na2SiO3/NaOH) an abundant effluent, generated in the alkaline fusion of zircon sand, represents a potential silica source to be converted in useful silica technological application. Actually, the generation of energy by environmental-friendly method is one of the major challenges for researchers. Solid Oxide Fuel Cells (SOFC) is efficient and environmentally clean technique to energy production, since it converts chemical energy into electrical power, directly. Apatite-type lanthanum silicates are promising materials for application as an electrolyte in intermediate temperature SOFC (IT-SOFC) because of their higher ionic conductivity, in temperatures of range 600–700 °C, than conventional zirconia electrolytes. In this work, pure (La9,56(SiO4)6O2,34) and Mg-doped (La9,8Si5,7Mg0,3O26,4) lanthanum silicate were synthesized, from that rich effluent. Using the sol-gel followed by precipitation method, the single crystalline apatite phase of both silicates was obtained by thermal treatment at 900 °C of their precursors. Sintered ceramic samples reached density of higher than 90%.
Glass ceramic sealants belonging to BAS (BaO-Alsub(2)Osub(3)-SiOsub(2) ternary system modified with Bsub(2)Osub(3) addition
2016 - SILVA, MAVIAEL J. da; BARTOLOME, JOSE F.; AZA, ANTONIO H. de; MELLO CASTANHO, SONIA
Four compositions in the BaO–Al2O3–SiO2 system modified with B2O3 were investigated with regard to their use as glassy seals in anode supported SOFC or iT-SOFC. The glassy system studied contains varying percentages of SiO2, Al2O3, B2O3, and high content of BaO as modifier (67–74%-wt). Their glass transition (Tg) and maximum densification point lies between 630 and 680 ◦C, and 734 ◦C to 828 ◦C, respectively. The viscosities of the four glasses are situated between 107 to 109.5 Pa.s, in the sealing range (730–830 ◦C). Heat treatment at 850 ◦C, revealed crystalline phases identified as BaAl2Si2O8 (hexacelsian) and BaSiO3. The thermal expansion coefficient (TEC) of the obtained glasses (8.8–10.5 ppm/K) was comparable to zirconia (YSZ) electrolyte, and shows chemical compatibility and high characteristic bond strength (up to 33 ± 7 MPa). The compositions with higher BaO contentin the system studied seem to be good candidates for iT-SOFC sealant application.
Cromito de lantânio
2015 - SETZ, L.F.G.; MELLO CASTANHO, S.R.H.; MORELLI, M.R.
O cromito de lantânio (LaCrO3 ) é um material cerâmico sintético, que apresenta como principais características boa condutividade elétrica em altas temperaturas (> 800 °C), estabilidade química e física em atmosferas oxidantes e redutoras e, significativa atividade catalítica quando na forma de pós. Estas características o tornam atrativo para diversas aplicações de interesse tecnológico, como catalisadores, resistências para fornos de alta temperatura e geração de energia elétrica, sendo que nesse campo é potencialmente o material mais adequado para utilização como interconector em células a combustível de óxido sólido (Solid Oxide Fuel Cell - SOFC). As características intrínsecas, propriedades e técnicas de processamento do cromito de lantânio são consideradas neste trabalho por meio de uma revisão dos principais estudos relatados ao longo dos últimos 40 anos.
Thermal properties of a barium borom silicate glass as a sealant for use in anode-supported solid oxide fuel cells
2015 - SILVA, MAVIAEL J.; REIS, SIGNO T. dos; MELLO CASTANHO, SONIA R.H. de
The Solid oxide fuel cell is a very efficient and clean source of energy. The planar design of SOFC requires sealant at the edges of the cell to prevent fuel leakage (H2, CH4, etc) and air mixing at its working temperature (700 to 900°C). The extreme operation conditions of current cell designs involve both high temperatures and highly corrosive environments. As a consequence is necessary a material to seal the chambers of the anode and cathode along each cell unit (the anodecathode-electrolyte and interconnects). The present work is an attempt to engineering glass compositions based on the BaO-Al2O3-SiO2-B2O3 system chosen due its thermal properties and good glass forming tendency. The glass formation or stability against crystallization and the coefficient of thermal expansion were determined by Differential Scanning Calorimeter and Dilatometric analysis, including sinterization curves. The main subject of this work is the development and selection of sealing glasses composition for SOFCs applications and also the development of new methodologies for preparation and evaluation of glass ceramics suitable for SOFC seals applications.
Strontium and cobalt doped-lanthanum chromite
2015 - SETZ, L.F.G.; SANTACRUZ, I.; LEON-REINA, L.; TORRE, A.G. De la; ARANDA, M.A.G.; MELLO CASTANHO, S.R.H.; MORENO, R.; COLOMER, M.T.
Perovskite powders prepared by combustion synthesis with a nominal composition of La0.800Sr0.200Cr0.920Co0.080O3.000 δ were obtained from the corresponding metal nitrates, and characterised in terms of in-situ phase development (crystalline structure and thermal behaviour). Synchrotron X-ray powder diffraction (SXRPD) and Rietveld analyses demonstrated that the as-prepared powder showed an orthorhombic perovskite structure with an estimated composition of La0.803Sr0.197Cr0.966Co0.034O3.000 δ. Second phases present in the as-prepared powder were m-LaCrO4, CoLa1.250Sr0.750O4.000, c-CoCr2.000O4.000 and m-SrCrO4.000. Sintering processes, including phase transition (from orthorhombic to rhombohedral) of the main phase and, melting/evaporation of second phases have been studied by DTA/TGA and dilatometric studies; the results were in full agreement with those detected by High-Temperature Synchrotron X-ray powder diffraction (HT-SXRPD). The transition temperature was determined to be 1380 1C by dilatometric studies, and between 1240 and 1405 1C by HT-SXRPD. Dye-pressed samples sintered at 1600 1C/4 h showed a density of 98.9 dth%. The phase transition is an irreversible process since the sintered perovskite, measured at room temperature after cooling, only showed the rhombohedral phase as main phase. The evaluation of the linearity of the conductivity versus the inverse of temperature and the activation energy values of the sintered material indicated that the electrical conduction occurs via the non-adiabatic small-polaron mechanism in either air or hydrogen atmosphere. In the reducing environment, the perovskite shows significantly reduced electrical conductivity compared with that in air, as it is expected for a p-type conductor. & 2014 Elsevier Ltd and Techna Group S.r.l. All rights reserved.
TG/DTA-MS evaluation of methane cracking and coking on doped nickel-zirconia based cermets
2014 - RESTIVO, THOMAZ A.G.; MELLO CASTANHO, SONIA R.H.; TENORIO, JORGE A.
Cermet materials based on metallic nickel and cubic zirconia are the key material for applications on solid oxide fuel cells and high temperature water electrolysis. The main advantage is the possibility of direct feeding a hydrocarbon fuel, like methane, or even an alcohol as a source of hydrogen. The reforming reaction on the Ni catalyst surface can produce hydrogen continuously. However, the resulting catalyst poisoning by carbon deposition (coking) imparts their broad application. The work shows the evaluation of coking tolerance of some cermets prepared by mechanical alloying techniques and compares new additives specially chosen in order to avoid coking and increase the catalytic activity. Refractory metal additives besides copper were added to the basic cermet. While copper is a known doping agent that avoids coking, the refractory metals (Mo and W) have a twofold effect: promote sintering at lower temperatures and increase Cu activity due to their mutual immiscibility. Results of TG/DTA-MS analysis demonstrate both refractory metals have increased the coking tolerance as well as the catalytic activity during diluted methane cracking. Molybdenum and tungsten additives are promised regarding the improvement of these cermet materials for high temperature electrochemical devices.
Synthesis and sintering behaviour of the lanthanum chromite doped with strontium and cobalt for SOFC interconnect applications
2007 - SETZ, L.F.G.; CORREA, H.P.S.; YAMAGATA, C.; MELLO CASTANHO, S.R.H.
Lanthanum Chromite has been the main candidate as interconnect material for high temperature fuel cell applications, SOFC. So all researches on the direction to clarify some aspects of this material continue to be an interesting contribution to understand and modify the behavior of the Lanthanum Chromite in use. The effort of this work is attaining doped Lanthanum Chromite by combustion synthesis, optimizing the parameters of the synthesis process and studying the influence of the conditioning powder process as milling, atmosphere and temperature of the sintering and also additives concentration on the final density, crystalline structures and expansion thermal behavior. The main characterization techniques used were BET determinations, Archimedes density method, dilatometry, scanning electronic microscopy, X ray diffraction and Rietveld method for refinements of the phases quantification. The homogeneous Lanthanum Chromite doped with Strontium and Cobalt with sintered densities around 97th% and thermal expansion coefficient compatible for SOFC applications (12x10-6°C) were attained with control of the adequate concentrations additives, synthesis conditions, the control of the atmosphere, time and temperature of the sintering process.
Microstructure design by mechanical alloying
2009 - RESTIVO, THOMAZ A.G.; MELLO CASTANHO, SONIA R.H.
Processamento e conformação tape casting de suspensões coloidais de LaCrOsub(3)
2008 - SETZ, LUIZ F.G.; MORENO, RODRIGO; CASTANHO, S.R.H. de M.
Rheological study of doped lanthanum chromite aqueous suspension
2011 - SETZ, L.F.G.; SANTACRUZ, I.; COLOMER, M.T.; MORENO, R.; MELLO CASTANHO, S.R.H.