Autothermal reforming of LPG was studied in a fixed-bed reactor by varying controlled parameters, such as reforming temperature, steam-to-carbon ratio (S/C), oxygen-to-carbon ratio (O/C) and catalyst. The conditions tested were two nickel-based catalysts, at 680-820 degrees C, with SIC of 0.30-1.9 and O/C of 0.64-1.4. In addition to controlled variables, it was found vapor composition of LPG withdrawn were not constant at different levels of tank exhaustion. The fuel vapor contained more heavy components and odorant-ethyl mercaptan as the bottle approached empty. Multivariate data analysis method, projections to latent structures (PLS), provided quantitative analysis of the effects of temperature, S/C, O/C, fuel composition and catalyst activity on reformate gas composition. Temperature, S/C and O/C were found to be the most important parameters for fuel conversion and avoiding carbon deposition. Sulfur poisoning by odorant was the main cause of catalyst deactivation. Composition of hydrocarbons in LPG vapor was shown to affect the autothermal reforming process, but the influence was less significant. Under test conditions, reformate gas composition generally approached equilibrium. The kinetically controlled methane reduction was well predicted by a PLS regression model. (c) 2006 Elsevier B.V. All rights reserved.