The kinetics of the isomerization of 1-butene to cis-2-butene and trans-2-butene, of I-pentene to cis-2-pentene and trans-2-pentene as well as of 1-hexene to cis-2-hexene and trans-2-hexene on sulfonated copolymer Amberlyst 15 in the gas phase was investigated. The Langmuir-Hinshelwood equations were adjusted to the results of the kinetic experiment using the values of adsorption equilibrium constants of the reactants from the adsorption measurements separately taken. The calculations were done by the Levenberg-Marquardt least-squares method using the Origin Microcal program. (c) 2005 Elsevier B.V. All rights reserved.