Title : Hydrogen production by SR of methanol on one dimensional Pt/CeO2-NR catalysts
1D catalysts Pt/CeO2-NR were synthesized by hydrothermal and impregnation methods respectively. These catalysts were evaluated in the steam reforming of methanol reaction (SRM) for hydrogen production. The Pt precursors used in this work were tetraaminplatinum nitrate (Pt(NH3)4(NO3)2), platinum acetylacetonate (CH3- COCHCO-CH3)2Pt, and hexachloroplatinic acid (H2PtCl6*6H2O) respectively. The catalysts were characterized by Adsorption-Desorption of N2 (BET), MEB, DRX, TPR, STEM-HAADF, and DRIFT. All the samples showed a typical diffraction peak of the cubic structure of the fluorite phase of CeO2. TPR profiles of Pt/CeO2-NR(Nit) and Pt/CeO2-NR (Acac) catalysts, showed reduction peaks at a lower temperature than Pt/CeO2-NR(Cl) catalysts. STEM-HAADF characterization showed small Pt nanoparticles on Pt/CeO2- NR(Nit) than Pt/CeO2-NR(Acac), this finding can be associated with the solvent used during the synthesis of the catalysts. Pt nanoparticles were identified by using the HAADF-STEM mode, on both Pt/CeO2-NR (Nit) and Pt/CeO2-NR (Acac) samples respectively. This technique, confirms the dispersion of the active phase on the matrix with Pt particle size ca. 1nm. Pt/CeO2-NR(Nit) sample showed the best performance on methanol conversion than other samples, this finding was associated with the higher Pt nanoparticles distributed along the CeO2-NR. While the lower catalytic activity of the samples synthesized from the salt-containing chlorine can be associated with the formation of oxychlorinated PtxOyClz species which affected the selectivity of the catalysts in the SRM reaction. High stability of the catalysts during the reaction was observed in all samples and confirmed by the MS technique because no further changes in the outlet signals on the real-time monitoring analysis by MS were observed.