In order to reconcile an increasingly large deviation (order of magnitude) of the ignition delay time at decreasing initial temperature, computed using the prior art kinetic schemes, with the available experimental values, a new skeletal mechanism (54 species, 94 reactions) for low-temperature (500-800 K) ignition of n- butane in air based on ab initio calculations is developed. The skeletal mechanism obtained accurately reproduces n-butane combustion kinetics for the practically important ranges of pressure. temperature and fuel-air equivalence ratio, especially in the low-temperature range. The elaborated first principal skeletal chemical kinetic mechanism of n-butane oxidation was validated against available experimental results for normal and elevated initial pressure (1-15 atm) using the Chemical Work Bench code. A good agreement with experiments was shown. (c) 2010 The Combustion Institute. Published by Elsevier Inc. All rights reserved.