Low-temperature Steam Reforming of Raw Bio-ethanol over Ceria-zirconia Supported Catalysts

Presently, steam reforming of bio-ethanol is considered as a promising route for generation of H2-rich mixtures with very low environmental concerns. However, the main challenges of such technology are related to catalyst deactivation due to carbon formation. In fact, bioethanol mixtures, besides water and ethanol, may contain several impurities, including higher alcohols, which decrease catalyst resistance towards coking. In the present work, ethanol steam reforming was investigated over bimetallic Pt-Ni based catalysts supported on ceria-zirconia. Preliminary tests were carried out under pure water/ethanol mixture and the impact of temperature (400 - 500 °C), space velocity (7,500 - 30,000 h-1) and H2O/C2H5OH molar ratio (3 - 9) on carbon formation rate was studied. Further, at chosen operative conditions, a model mixture containing 1 mol% of the main bioethanol impurities (C2H4O, C3H7OH, C4H9OH, C5H11OH) was fed to the reformer and its effect on catalyst stability was studied at 450 °C, 15,000 h-1 and r.a.=6.