Equilibrium composition of ethanol steam reforming reaction to produce H_2 applied to Ni, Go and Pt/hydrotalcite-WOx catalysts

摘要

The purpose of this work was to investigate the difference between the experimental molar fractions of products obtained during the evaluation of Pt, Co and Ni/Hydrotalcites-WOx catalysts and the calculated composition in equilibrium for the ethanol steam reforming reaction. Mole fractions of H_2, CO_2, CH_3CHO, CH_2CH_2, CH_4 and H_2O were calculated using the stoichiometric and the minimization of the Gibbs free energy methods. The difference between calculated and experimental mole fractions was used to determine the intermediate and final compounds in the reaction mechanism and also how close to equilibrium are the reactants and final products. In addition, by comparing H_2 and the conversion, it was possible to distinguish which series of catalysts were more active. From our experimental results, the conversion order of these catalysts was as follows: Pt ＞ Ni ＞ Co and the reaction rate per g-atm of metal was: Pt » Ni ≈ Co.