Cobalt Catalysts
Mostrando 25-36 de 40 artigos, teses e dissertações.
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25. Degradação do PMMA através da reação despolimerização uitlizando catalisadores de óxidos mistos
In this work, mixed oxides were synthesized by two methods: polymeric precursor and gel-combustion. The oxides, Niquelate of Lanthanum, Cobaltate of Lanthanum and Cuprate of Lanthanum were synthesized by the polymeric precursor method, and treated at 300 C for 2 hours, calcined at 800 C for 6h in air atmosphere. In gel-combustion method were produced and oxi
Publicado em: 2009
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26. Electroless cobalt alloys: magnetic and catalytic properties / Ligas à base de cobalto depositadas quimicamente: propriedades magnéticas e catalíticas
A influência de variáveis do banho na composição, microestrutura e nas propriedades magnéticas de filmes de CoB preparados por deposição química foi estudada. Dois diferentes tipos de agentes complexantes foram utilizados: citrato de sódio e Glicina. Filmes com menor teor de boro foram obtidos com o uso de Glicina como complexante. A deposição de
Publicado em: 2009
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27. Rota hidrometalúrgica de recuperação de molibdênio, cobalto, níquel e alumínio de catalisadores gastos de hidrotratamento em meio ácido
This work describes a hydrometallurgical route for processing spent commercial catalysts (CoMo and NiMo/Al2O3). Samples were preoxidized (500 ºC, 5 h) in order to eliminate coke and other volatile species present. The calcined solid was dissolved in concentrated H2SO4 and water (1:1 vol/vol) at 90 ºC; the insoluble matter was separated from the solution. M
Química Nova. Publicado em: 2008
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28. RemoÃÃo de tiofeno utilizando adsorventes preparados por mistura fÃsica
The need for cleaner fuels has increased that the studies aimed at reducing levels of sulfur in gasoline. The presence of sulfur compounds in fractions of oil is highly undesirable because it results in corrosion and environmental pollution. The hydrodesulfurization is the main process responsible for removing sulfur from most of the fuel industry of oil ref
Publicado em: 2008
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29. "Aplicação de catalisadores de níquel e cobalto preparados via precursores do tipo hidrotalcita nas reações de reforma a vapor, oxidação parcial e reforma oxidativa do metano" / "Application of nickel and cobalt catalysts prepared via hydrotalcite-type precursors in the reactions of steam reforming, partial oxidation and oxidative reforming of methane"
One of the most important applications of methane is the syngas production, a mixture of H2 and CO. Three processes can lead to syngas formation from methane: steam reforming, CO2 reforming and partial oxidation. Various non-noble metal catalysts were studied in these processes, although the carbon deposition or the metal sinterization is always observed. Ca
Publicado em: 2007
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30. Desenvolvimento de catalisadores de ródio e cobalto para a reforma a vapor do etanol.
The development of technologies based on the use of biofuels has taken the attention of the scientific community, due to the current dependence on fossil fuels, which results in an increase of air pollution. This pollution increase is related to public health problems and climate changes. In this context, the use of fuel cells moved by hydrogen is a mean of
Publicado em: 2007
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31. CARBON NANOTUBES DECORATED WITH COBALT PARTICLES / NANOTUBOS DE CARBONO DECORADOS COM PARTÍCULAS DE COBALTO
Carbon nanotubes since they are observed for the first time have been attracted attention due to their structure and unique electronic properties. Many applications, as support materials for catalysts, are proposed because of their aspect ration and good electrical conductivity. These properties favor a better dispersion and stabilization of the metallic nan
Publicado em: 2007
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32. Síntese, caracterização e aplicação de catalisadores mistos contendo cobalto e cobre
Studies on the use of catalysts have been directed to develop new processes taking into consideration the economic point of view (for example, substitution for cheaper raw materials) as well as the green chemistry aspects. The majority of supported catalysts is prepared by the impregnation method of the metallic salt over a material of high specific surface
Publicado em: 2007
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33. Copper and cobalt catalysts supported on CeO2, TiO2 and CeO2-TiO2 to reduction NO by CO / Utilização de catalisadores de cobre e cobalto suportados em CeO2, TiO2 e matrizes de CeO2-TiO2, para redução de NO com CO na ausência ou presença de O2
A redução da emissão de compostos nitrogenados tem sido um dos grandes desafios da área de proteção ambiental e o tratamento catalítico pode reduzir significativamente tal emissão. Neste caminho, têm sido testadas várias categorias de catalisadores. Considerando-se o potencial de utilização de catalisadores de cobre e de cobalto nos processos de
Publicado em: 2007
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34. Recuperação de metais de catalisadores de hidrorrefino usados via fusão com KHSO4
This work describes a process for metal recovery from spent NiMo and CoMo/Al2O3 commercial hydrorefining catalysts. The samples were treated by fusion with potassium hydrogen sulfate (5 h, 600 ºC) with a KHSO4/catalyst mass ratio of 10:1. After fusion the solid was solubilized in water (100 ºC), leaving silicon compounds as residue. Losses of nickel and co
Química Nova. Publicado em: 2006-07
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35. Efeito do teor metálico em catalisadores Co/Al2O3 aplicados à reação de reforma a vapor de etanol
The development of cobalt catalysts to produce hydrogen from ethanol is the goal of this investigation. Co/Al2O3 catalysts were prepared by impregnation and characterized by atomic absorption, nitrogen adsorption, X-ray diffraction, Raman spectroscopy, temperature programmed reduction and carbon analysis. The catalysts contained Co3O4 oxide and Co3+ and Co2+
Química Nova. Publicado em: 2005-08
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36. CATALYSTS SUPPORTED IN MICRO AND MESOPOROUS MOLECULAR SIEVES FOR THE FISCHER- TROPSCH SYNTHESIS / CATALISADORES SUPORTADOS EM PENEIRAS MOLECULARES MICRO E MESOPOROSAS PARA A SÍNTESE DE FISCHER-TROPSCH
The Fischer- Tropsch synthesis converts the synthesis gas (H2 + CO), in a complex variety of hydrocarbons, using a catalyst (Co/Al2O3 normally) were introduced to the used supports by the wetness incipient impregnation. The samples were analyzed by several techniques such as: plasma- emission spectrometry (ICP- EAS), N2 physical adsorption by BET method, X-r
Publicado em: 2004