Ethanol Steam Reforming on Lanthanum Ni-ZrO2 Catalysts

Hydrogen is defined the future energy carrier, and ethanol steam reforming can be a sustainable process for its production. Promoting the addition of lanthanum on a Ni-zirconia catalyst was evaluated, with a focus on the lanthanum introduction method (incipient wetness impregnation and coprecipitation). The lanthanum addition strongly affected the morphological, structural, and chemical features of the catalysts. It particularly affected the stabilization of the zirconia phase and the surface basic properties. For the promoted materials, a higher ethanol conversion and hydrogen yield were obtained. The best catalytic results with the catalyst prepared via promoter impregnation, 81% of ethanol conversion and 25% of H2 yield after 16 h of reaction, were obtained. By a CO2-TPD technique, it was estimated to be the most basic material. DRIFT analyses were used to understand the effect of basic sites in the reaction pathway. High numbers of medium and strong basic sites reduced the formation of unwanted intermediates such as ethylene. In this way, the formation of coke deposits is reduced. SEM, TG analyses, and Raman spectroscopy confirmed the results.