Pt Based Catalysts
Mostrando 13-24 de 29 artigos, teses e dissertações.
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13. Catalisadores à base de platina frente a correntes de H2 contendo acetaldeído geradas via reforma do etanol / Platinum-based catalystic in the face of current H2 containing acthaldehyde generated via reforming of ethanol
Due to the greenhouse effect, hydrogen production from bioethanol reforming is a very important subject in heterogeneous catalysis research. Pt based catalysts are employed in H2 purification processes and also as electrocatalysts of PEM (Proton Exchange Membrane) fuel cells. Hydrogen obtained from ethanol reforming may contain acetaldehyde and small amounts
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 23/05/2011
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14. Transition metal-based bimetallic catalysts for the chemoselective hydrogenation of furfuraldehyde
Neste trabalho foi estudada a hidrogenação quimiosseletiva em fase líquida do furfural, empregando-se catalisadores baseados em Pt, Rh e Ni. Sistemas bimetálicos, contendo diferentes quantidades de estanho, foram obtidos por meio de reações de superfície controlada entre um catalisador monometálico e Sn(C4H9)4. Quando foram utilizados catalisadores m
Journal of the Brazilian Chemical Society. Publicado em: 2010
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15. Catalytic materials based on Pt, Pb and carbon powder to the oxidation of formic acid in acid medium / Materiais catalíticos baseados em PT, PB e pó de Carbono para a oxidação de ácido fórmico em meio ácido
Proton Exchange Membrane Fuel Cell (PEMFC) that operates with formic acid as fuel (Direct Formic Acid Fuel Cell, DFAFC) constitutes a promising power source to be used in portable devices. In this context, this work aims to find efficient anodes to be used in this kind of system. All materials, based in Pt, Pb and carbon black were synthesized by the Sol-Gel
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 19/02/2009
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16. Desenvolvimento de nanocamadas e nanocristais de Óxido de Zircônio aplicados a catálise / Development of nanolayers and nanocrystals of Oxide of Zirconium applied the catalysis
This work investigate the synthesis and characterization of a catalytic support of -alumina with a nanolayers and nanocrystals of ZrO2. The incorporation of the platinum began during and after the formation of the catalytic support. The technology is based on the Pechini method. The nanolayer was applied to cover the surface of the γ-alumina, av
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 14/09/2007
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17. Desenvolvimento de catalisadores bifuncionais de óxido de zircônio modificado por óxidos de tungstênio e molibdênio contendo platina para a reação de isomerização de n-parafinas / Development of bifunctional catalysts on zircon oxide modify by tungsten and molybdenum oxides contain platinum for nparaffin isomerization
Bifunctional catalysts based on zircon oxide modified by tungsten (W = 10, 15 and 20 %) and by molybdenum oxide (Mo= 10, 15 e 20 %) containg platinum (Pt = 1%) were prepared by the polymeric precursor method. For comparison, catalysts the tungsten base was also prepared by the impregnation method. After calcinations at 600, 700 and 800 C, the catalysts were
Publicado em: 2007
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18. Estudo do efeito da dopagem da alumina com CÃrio em catalisadores Pt/CeZrO2/Al2O3 na reaÃÃo de oxidaÃÃo parcial do Metano
The transformation of methane into liquid fuels has drawn a lot of attention in the last years due to both economical and environmental concerns. Currently, the main route to obtain synthesis gas from methane is the steam reforming. The major problems associated with this route are the high temperatures and pressures required. Nowadays, the partial oxidation
Publicado em: 2007
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19. Influência de M/C (M = Mo, Cu, Fe e W) incorporado à camada difusora do eletrodo de difusão de gás frente à reação de oxidação de hidrogênio na presença de CO
The performance of proton exchange membrane fuel cells (PEMFC) with Pt-based anodes is drastically lowered when CO-containing hydrogen is used to feed the system, because of the strong adsorption of CO on platinum. In the present work the effects of the presence of a conversion layer of CO to CO2 composed by several M/C materials (where M = Mo, Cu, Fe and W)
Química Nova. Publicado em: 2007
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20. Preparação e caracterização de materiais com base zeolítica para aplicação em catálise
Today, heterogeneous catalysts are commonly used in chemical industries and became very important to several commercial processes. A key problem in catalysis is the evaluation of acid parameters in solid acids and their correlation with catalytic activity. This work involves the study of acidity for zeolites and heteropolyacids and their activity in model re
Publicado em: 2007
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21. Efeito da temperatura de calcinação em catalisadores de platina a base de óxidos de cério e zircônio mássicos e suportados em alumina nas reações de oxidação parcial e reforma autotérmica do metano
The transformation of methane into higher value products became more important in recent years due to the search for new energy sources. The use of partial oxidation and autothermal reforming of methane can give synthesis gas with a H2/CO ratio of 2, that is very adequate for the Fischer-Tropsch synthesis. In order to develop this process, the use of catalys
Publicado em: 2006
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22. "Developments of carbn-dispersed electrocatalysts for cathodes of alkaline fuel cells" / "Desenvolvimento de eletrocatalisadores dispersos para o cátodo de células a combustível alcalinas"
The oxygen reduction reaction (ORR) was studied on electrodes formed by Pt monolayers deposited on different metallic substrates, and on carbon-supported electrocatalysts composed by PtM/C (M = V, Cr e Co) and AgPt/C alloys, and on different Mn oxides (Mn3O4/C, Mn2O3/C and MnO2/C) in alkaline electrolyte. The experimentally measured electrocatalytic activiti
Publicado em: 2006
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23. Estudo da Adição do Promotor Cu aos Catalisadores Pt/Al2O3 e Pt/Nb2O5 para a Oxidação Seletiva de CO / Study of the Addition of Cu Promoter to the Pt/Al2O3 and Pt/Nb2O5 catalysts for the Selective Oxidation of CO
The fuel cells are an alternative to generate energy without polluting the environment. They produce electric energy through the reaction of hydrogen with the oxygen from air. The product of the reaction is water. It is an interesting form of generation energy because its a clean technology. The hydrogen used as combustible for the fuel cells is proceeding f
Publicado em: 2005
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24. "Dependence of the selectivity of the methanol and ethanol electrooxidation reaction on Pt/C and PtRh/C nanoparticles" / "Dependência da seletividade da reação de eletro-oxidação de metanol e etanol sobre nanopartículas de Pt/C e PtRh/C"
The methanol and ethanol electrooxidation is a subject of intense studies in electrocatalysis. The aim of such attention concerning this alcohol electrooxidation activity is due to development of new energy converter systems more efficient and less pollutant. The electrocatalysis research has been also directed to nanoparticle systems. Metallic particles in
Publicado em: 2005