Hydrogen production in methanol reforming with Pt-Pd catalysts supported on CeO₂ nano rods

Cerium oxide (CeO₂) was synthesized by the hydrothermal method and was used as a support in the Pt, Pd and Pt-Pd catalysts. The impregnation of the active phase of platinum (Pt) and/or palladium (Pd) was carried out using the incipient wetting method, obtaining mono metallic catalysts of Pt/CeO₂ and Pd/CeO₂ and a bimetallic one of Pt-Pd/CeO₂. The metal load in all the catalysts was 2% mol, in the bimetallic catalyst there is a ratio of 50:50% mol of each of the metals with respect to the total load. The characterization of the catalysts was carried out using the techniques of: temperature programmed reduction (TPR), X-ray diffraction (XRD), transmission electron microscopy (Tem) and surface area (Bet). The results obtained from Tem showed that the Pt/CeO₂ catalyst has a better dispersion of the active phase on the surface of the CeO₂ nano rods. While for the Pd/CeO₂ catalyst, the active phase presented less dispersion. Which causes Pd to have the largest particle size, compared to Pt. In the methanol reforming reaction, it was observed that the catalyst with the smallest particle size has the best catalytic properties in the conversion of methanol (CH₃OH), in the production of hydrogen (H₂) and lower content of carbon monoxide (CO). On the other hand, a positive effect of platinum was observed when added to the Pd/CeO₂ catalyst, because the mixture of both metals showed low selectivity towards carbon monoxide (CO), better production of hydrogen and carbon dioxide (CO₂), indicating that the bimetallic Pt-Pd/CeO₂ catalyst is promising for use in the methanol reforming reaction for H₂ production. (author)