Investigation on Deposition of Oxide Support for Steam Reforming of Ethanol on a Microreactor

Abstract

Numerous factors can influence the production of hydrogen by Ethanol Steam Reforming (ESR), including the homogeneity and distribution of the catalyst throughout the reaction area, as this directly affects the surface area and the catalytic sites. The aim of this work is to improve the deposition conditions of the catalytic support in a microchannel reactor in order to increase the available area for ESR. Thus, parameters such as the concentration of the support material and the concentration of the binding agent to prepare the suspension, as well as the particle size of the oxide precursor of the suspension were evaluated using a factorial design to determine the influence of these factors on the deposition thickness formed in the cross section of the microchannels of the reactor. The determination of the thickness was verified through images obtained by scanning electron microscopy and the deposition was verified by X-ray photoelectron spectroscopy. When statistically analyzing the results obtained, the factor relating to the particle size of the oxide precursor of the suspension for deposition was what generated statistical influence. Qualitatively, it was also possible to observe that the other parameters evaluated, support and binder concentration, obtained better viscosity and adhesion results at intermediate values. SEM analysis made it possible to analyze qualitatively and quantitatively (using ImageJ software) the increase in thickness and quality of the deposited layer. The XPS analysis ensured that the elements of the active and supporting phases of the catalyst were well impregnated during deposition. Therefore, the factorial design of the experiments made it possible to investigate the different effects of the independent variables to know the thickness of the deposited support.