Jet fuel reforming was analyzed for both partial oxidation and autothermal reforming processes based on the chemical-reaction equilibria with possible use of solid oxide fuel cells in the auxiliary power units of aircraft to reduce pollutant emissions. Parameters considered in this paper were the oxygen-to-carbon ratio (0-0.7), the steam-to-carbon ratio (0-1), and the reformer temperature (500-1200 degrees C). The product compositions and energy change of the reforming process were calculated for 12 hydrocarbons of a surrogate jet fuel under the isothermal conditions and the jet fuel under the adiabatic conditions. Solid carbon in the form of graphite was included as one of the products. The effect of 12 hydrocarbons on the oxygen-to-carbon ratio at the carbon formation boundary was negligible above 700 degrees C. Under isothermal conditions, the maximum yield of hydrogen, carbon monoxide, or syngas was at the carbon formation boundary. Under adiabatic conditions, the minimum required oxygen-to-carbon ratio to avoid carbon formation was decreased from 0.52 to 0.38 and the corresponding temperature was reduced from 844 to 617 degrees C with the increase of steam-to-carbon ratio from 0 to 1 for the jet fuel reforming. The maximum reforming efficiency based on the synthesis gas was about 83% for the considered steam-to-carbon ratios. (C) 2007 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.