Visando a produção de hidrogênio, como uma fonte renovável de energia, estudaram-se as reações de reforma a vapor e oxidativa do etanol sobre catalisadores de Ru/CeO2-Al2O3. Foi verificado o efeito do suporte e das interações metal/suporte sobre a atividade e seletividade para as reações. Os suportes e catalisadores foram caracterizados por fisissorção de nitrogênio pelo método B.E.T., para avaliar as áreas superficiais específicas, espectroscopia dispersiva de raios-X (EDX), para determinar a distribuição qualitativa da fase metálica sobre os suportes, difração de raios-X (DRX), para identificação das fases óxidas, espectroscopia na região do ultra-violeta e do visível (UV-vis NIR), para avaliar as transições eletrônicas presentes no material, e redução a temperatura programada (RTP), para avaliação do comportamento de redução e das fases redutíveis. Através dos ensaios catalíticos, pode-se verificar que todos os catalisadores foram ativos para ambas as reações de reforma, sob as temperaturas de 400, 600 e 700ºC, onde a conversão do etanol aumentou com o aumento da temperatura e com o aumento da adição de CeO2 ao suporte catalítico. O catalisador 3%Ru/CeO2 foi o mais ativo frente a reação de reforma a vapor e o 3%Ru/25%CeO2-Al2O3 o catalisador mais ativo para a reação de reforma oxidativa do etanol. A maior seletividade para H2 foi obtida a 600ºC para ambas as reações de reforma, com exceção dos catalisadores 3%Ru/20%CeO2-Al2O3, que foi mais seletivo a 700ºC para a reforma a vapor, e 3%Ru/CeO2, que foi mais seletivo a 400ºC para a reforma oxidativa. / Aiming at hydrogen production, as a source of renewable energy, Ru/CeO2-Al2O3 catalysts were studied in ethanol steam reform and ethanol oxidative reforming. The effect of the support and metal/support interaction was verified on the activity and selectivity of the reactions. The supports and catalysts were characterized by x-rays dispersive spectroscopy (XDS), to verify the qualitative distribution of the metallic phase on the supports, x-rays diffraction (XRD), for identification of the crystalline oxide phases, spectroscopy in the region of the ultraviolet and the visible (UV-vis NIR), to evaluate the electronic transitions present in the material, and temperature programmed reduction (TPR), for evaluation of the reductive phases. According to the catalytic tests, all catalysts were active for both reactions under the temperatures of 400, 600 and 700ºC, where the ethanol conversion increased together with the increase of the temperature and, with the addition of CeO2 to the catalytic support. The 3%Ru/CeO2 catalyst was the most active for ethanol steam reforming and the 3%Ru/25%CeO2-Al2O3 catalyst was the most active for ethanol oxidative reforming. The higher selectivity for H2 occurred at 600ºC for both reactions, excluding the 3%Ru/20%CeO2-Al2O3 catalyst, which was more selective at 700ºC for steam reforming, and the 3%Ru/CeO2 catalyst, which was more selective for the oxidative reforming at 400ºC.

Visando a produção de hidrogênio, como uma fonte renovável de energia, estudaram-se as reações de reforma a vapor e oxidativa do etanol sobre catalisadores de Ru/CeO2-Al2O3. Foi verificado o efeito do suporte e das interações metal/suporte sobre a atividade e seletividade para as reações. Os suportes e catalisadores foram caracterizados por fisissorção de nitrogênio pelo método B.E.T., para avaliar as áreas superficiais específicas, espectroscopia dispersiva de raios-X (EDX), para determinar a distribuição qualitativa da fase metálica sobre os suportes, difração de raios-X (DRX), para identificação das fases óxidas, espectroscopia na região do ultra-violeta e do visível (UV-vis NIR), para avaliar as transições eletrônicas presentes no material, e redução a temperatura programada (RTP), para avaliação do comportamento de redução e das fases redutíveis. Através dos ensaios catalíticos, pode-se verificar que todos os catalisadores foram ativos para ambas as reações de reforma, sob as temperaturas de 400, 600 e 700ºC, onde a conversão do etanol aumentou com o aumento da temperatura e com o aumento da adição de CeO2 ao suporte catalítico. O catalisador 3%Ru/CeO2 foi o mais ativo frente a reação de reforma a vapor e o 3%Ru/25%CeO2-Al2O3 o catalisador mais ativo para a reação de reforma oxidativa do etanol. A maior seletividade para H2 foi obtida a 600ºC para ambas as reações de reforma, com exceção dos catalisadores 3%Ru/20%CeO2-Al2O3, que foi mais seletivo a 700ºC para a reforma a vapor, e 3%Ru/CeO2, que foi mais seletivo a 400ºC para a reforma oxidativa. / Aiming at hydrogen production, as a source of renewable energy, Ru/CeO2-Al2O3 catalysts were studied in ethanol steam reform and ethanol oxidative reforming. The effect of the support and metal/support interaction was verified on the activity and selectivity of the reactions. The supports and catalysts were characterized by x-rays dispersive spectroscopy (XDS), to verify the qualitative distribution of the metallic phase on the supports, x-rays diffraction (XRD), for identification of the crystalline oxide phases, spectroscopy in the region of the ultraviolet and the visible (UV-vis NIR), to evaluate the electronic transitions present in the material, and temperature programmed reduction (TPR), for evaluation of the reductive phases. According to the catalytic tests, all catalysts were active for both reactions under the temperatures of 400, 600 and 700ºC, where the ethanol conversion increased together with the increase of the temperature and, with the addition of CeO2 to the catalytic support. The 3%Ru/CeO2 catalyst was the most active for ethanol steam reforming and the 3%Ru/25%CeO2-Al2O3 catalyst was the most active for ethanol oxidative reforming. The higher selectivity for H2 occurred at 600ºC for both reactions, excluding the 3%Ru/20%CeO2-Al2O3 catalyst, which was more selective at 700ºC for steam reforming, and the 3%Ru/CeO2 catalyst, which was more selective for the oxidative reforming at 400ºC.

By the everyday increasing enthusiasm for using renewable-sustainable sources in energy production area, focusing on one and optimizing it in the best possible way should be of much interest. Biogas production from anaerobic digestion of wastes is a well known energy source which could be applied more efficiently if the CO2portion of it would be upgraded to CH4as well. There is a methanation reaction which could convert carbon dioxide to methane with the use of hydrogenation. In this report, the effort is to simulate this methanation reactor which is a catalytic bed of ruthenium on alumina base. The temperature change and its’ effect on reaction kinetics and equilibrium, also deriving designing parameters for the catalyst bed are different tasks which was tried to be covered in this thesis work. Based on calculations, the reactor can operate isothermally or adiabatically. The point is that each method has its own cons and pros. For the isothermal case finally the optimum temperature to run the reaction is decided to be 600 K in 10 bar total pressure. In adiabatic case then it is understood to work on interstage cooling strategy which in given conditions came to the number of 6 for reactors and 5 for interstage cooling devices. Afterwards it is thought to apply some technical changes to conventional adiabatic method and recycle some part of the product to the entrance of the reactor and assist the conversion. In this method number of reactors would be reduced to 2 and one heat exchanger in the middle. Selecting the best process in large scale treatment, needs lots of economical analysis and detail design while in small scale condition the most preferred method to run the reaction is isothermal.

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