Desenvolvimento e caracterizaÃÃo de um sistema catalÃtico Ni(5%)/γ-Al2O3 aplicado à reforma sÃca do metano

AUTOR(ES)
DATA DE PUBLICAÇÃO

2002

RESUMO

It has been shown that methane reforming with carbon dioxide has a great potential in the chemical industry being used as storage and transformation systems of clear energy due to your reversibility and endothermicity. Furthermore, this process product the best proportion in H2:CO (1:1) recommended for oxo-alcohols and fuels obtention. These fuels are known for having no sulphur and nitrogen contaminants, which implies a first grade feedstock for the synthesis industry. The thermodynamics of this process is very important as with a high degree of certainty the behavior of the reaction as a function of the temperature, pressure and the composition of the reagents may be predicted. The synthesized and characterized catalyst used in this work was Ni(5%)/γ-Al2O3; due its well known catalytic activity and stability, cost and availability. It consisted of nickel supported on γ-Al2O3 was prepared by wet the impregnation technique. For this process a solution of Ni(NO3)2.6H2O in water was used. The γ-Al2O3 grains were impregnated with the salt solution in a rotating evaporator under vacuum. The catalyst was dried at 120ÂC at atmospheric pressure in a pure argon flow at 100 mL/min for 12 hours. The catalyst was then reduced in a pure hydrogen atmospher at a flow of 50 mL/min, at atmospheric pressure and at 550ÂC. The catalyst was characterized by different analytical methods as: Atomic Absorption Spectroscopy (AA), X-Ray Diffraction (XRD), Electronic Scanning Microscopy (ESM), X-Ray Photoelectron Spectroscopy (XPS) and Infrared Spectroscopy (IRS). Catalytic activity analysis experiments were performed in a differential reactor with the Ni(5%)/γ-Al2O3 catalyst (50 mg) a flow of 100 mL/min was used with a mixture of CH4 : CO2 : Ar = 10 : 15 : 75 under atmospheric conditions and at 850ÂC. Products were analyzed by a on line gas chromatograph (CG-Master/TDC/Cromosorb-102). The conversions were in the range of 80% in the first 10 hours and 60% after 92 hours of experiments. The proposed model was well adjusted to the experimental data

ASSUNTO(S)

methane reforming engenharia quimica methane catÃlise nickel catalysis reforma do metano diÃxido de carbono nÃquel carbon dioxide

ACESSO AO ARTIGO

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