JOAO COUTINHO FERREIRA
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Artigo IPEN-doc 28845 Preparation and characterization of high-performance Ni-based core-shell catalyst for ethanol steam reforming2022 - MORAES, TAMARA S.; BERGAMASCHI, VANDERLEI S.; FERREIRA, JOAO C.; SPINACE, ESTEVAM V.A core–shell catalyst, based on nickel nanoparticles supported on silica nanospheres and surrounded by ceria, was tested for ethanol steam reforming (ESR) reaction (H2O/ethanol: 3/1) under low-temperature conditions (400, 500 and 600 °C) in order to test its stability during the reaction. Two other catalysts of Ni supported in SiO2 and CeO2 were also synthesized to be compared with the core–shell catalyst in the ESR. All catalysts showed excellent activity at 500 and 600 °C with 100% ethanol conversion. Increasing the reaction temperature, carbon deposition on the surface of the catalysts decreases throughout the reaction. The core–shell catalyst showed high coke inhibition capacity in the ESR at 600 °C, without coke formation for at least 100 h of reaction. On the other hand, after 20 h of ESR at 600 °C, Ni–SiO2 and Ni/CeO2 catalysts showed formation of 6.3 and 5.2 mgC/(gcat.h) of coke, respectively. The strong redox capacity of ceria together with the change in catalyst structure due to the deposition of cerium oxide on top of Ni particles led to an excellent ESR activity of this catalyst.Artigo IPEN-doc 25045 Ni supported Ce0.9Sm0.1O2-δ nanowires2019 - RODRIGUES, THENNER S.; MOURA, ARTHUR B.L. de; SILVA, FELIPE A. e; CANDIDO, EDUARDO G.; SILVA, ANDERSON G.M. da; OLIVEIRA, DANIELA C. de; QUIROZ, JHON; CAMARGO, PEDRO H.C.; BERGAMASCHI, VANDERLEI S.; FERREIRA, JOAO C.; LINARDI, MARCELO; FONSECA, FABIO C.We reported herein the synthesis in high yields (> 97%) of Ce0.9Sm0.1O2-δ nanowires displaying well-defined shape, size, and composition by a simple, fast, and low-cost two-step hydrothermal method. The Ce0.9Sm0.1O2-δ nanowires synthesis was followed by the wet impregnation of Ni without the utilization of any stabilizing agent. The Ni/Ce0.9Sm0.1O2-δ nanowires showed higher surface area, high concentration of oxygen vacancies at surface, and finely dispersed Ni particles with significantly higher metallic surface area as compared with catalysts prepared from commercial materials with similar compositions. Such unique and improved properties are reflected on the catalytic performance of the Ni/Ce0.9Sm0.1O2-δ nanowires towards ethanol steam reforming. The nanowires exhibited high yields for hydrogen production (∼60% of selectivity) and an exceptional stability with no loss of activity after 192 h of reaction at 550 °C. The reported results provide insights and can inspire highyield production of nanostructured catalysts displaying controlled and superior properties that enable practical applications in heterogeneous catalysis.Artigo IPEN-doc 23591 Preparação e caracterização de catalisadores de níquel suportados em céria para obtenção de hidrogênio a partir da reforma a vapor do etanol2016 - URBANINHO, A.B.; BERGAMASCHI, V.S.; FERREIRA, J.C.The Ni/Ce catalysts for were prepared by co- precipitation method with a view to their use in steam reforming of ethanol to produce a hydrogen-rich gas mixture. The catalysts were characterized by scanning electron microscopy; x-ray dispersive Spectroscopy and surface area BET method. This paper proposes to prepare, characterize and test nickel catalyst supported on cerium in order to obtain a material with higher activity and selectivity of the catalyst using the steam reforming reaction of ethanol, by varying the reaction temperature, molar ratio water/ethanol and uptime. The catalytic tests were monitored by chemical analysis of syngas from steam reforming of ethanol using an analysis online by gas Chromatograph in the reactor.Resumo IPEN-doc 22970 Preparação e caracterização de catalisadores de níquel suportados em céria para obtenção de hidrogênio a partir da reforma a vapor do etanol2016 - URBANINHO, ANDRE B.; FERREIRA, JOAO C.Artigo IPEN-doc 10700 Resolucao do sistema residuario U (VI)-etanol-piridina2005 - FERREIRA, J.C.; LAINETTI, P.E.O.; CARVALHO, F.M.S.; ABRAO, A.