Ethanol steam reforming over Pt/Al2O3 and Rh/Al2O3 catalysts: the effect of impurities on selectivity and catalyst deactivation. Applied Catalysis A: General, 529, pp. 98-107. (doi:10.1016General, 529, pp. 98-107. (doi:10. /j.apcata.2016 This is the author's final accepted version.There may be differences between this version and the published version. You are advised to consult the publisher's version if you wish to cite from it. impurities. The addition of 1 mol % C 3 alcohols (1-propanol and isopropyl alcohol)significantly decreased the conversion of ethanol and increased the rate of catalyst deactivation. This deactivation of the catalyst in the presence of C 3 alcohols was attributed to high olefin formation and incomplete decomposition of the C 3 alcohols, which deposited over the catalysts as coke. Propanal, propylamine and acetone addition to the water/ethanol mixture resulted in rapid metal deactivation and a loss of steam reforming activity over the Pt/alumina although ethanol decomposition continued. In contrast the Rh/alumina did not lose all steam reforming activity when acetone and propylamine were added as impurities. On both the catalysts alcoholic impurities produced a large number of carbon nanotubes (CNTs).