Hydrogen production from ethanol over bimetallic Rh-M/CeO2 (M = Pd or Pt)

The reaction of ethanol for the production of hydrogen has been studied over a series of metal supported CeO2 catalysts. The study is conducted by TPD, steady state reaction, XPS, TEM, and infrared spectroscopy. TPD gave evidence for the role of Rh in dissociating the carbon–carbon bond needed for efficient production of hydrogen molecules. IR of CO adsorption at 90 K revealed that Rh particles are most likely in very small clusters as evidenced by a single Otriple bond; length of mdashC–Rh IR band at 2020 cm−1. TEM did not show conclusive evidence for the presence of the metal on-top of the CeO2 support, yet the Rh-Pd/CeO2 used catalyst has features that might be attributed to epitaxial growth of the noble metal along the (1 1 1) surface of the CeO2 support. Considerable reconstruction of the CeO2 support is seen for the used catalysts, in addition. Reforming of ethanol to hydrogen using (3 moles of water per mole of ethanol) was very efficient particularly above 650 K where hydrogen selectivity reaches 60 vol.%. At these temperatures hydrogen production from reforming of methane takes place.