Density functional theory has been used to study the thermodynamics associated with steam reforming of ethanol under cold plasma conditions The calculation results showed that the only thermodynamic obstacle of the production of hydrogen, carbon monoxide, methane and acetaldehyde was the dissociation of ethanol and steam molecules, which was easy to be overcome under cold plasma conditions. The formation of hydrogen and carbon monoxide was through a multi-step pathway via the methoxy radical conversion and dissociation of formaldehyde, while the recombination of H(center dot) generated extra hydrogen The syntheses of ethane and butane are from the recombination of CH(3)(center dot) and CH(3)CH(2)(center dot), which could be primarily generated through ethanol dissociation The structure of ethanol anion were also studied in this work. Theoretical calculation showed that the ethanol anion was less stable than the neutral molecule The route for the formation of CH(3)(center dot) and CH(2)OH(center dot) from ethanol anion is thermodynamically favorable (C) 2009 Professor T Nejat Veziroglu. Published by Elsevier Ltd All rights reserved