The production of pure hydrogen from renewable or fossil energy sources can be achieved by purifying the syn gas obtained as a result of a steam gasification process. Depleting of the syn gas carbon-containing compounds by means of CO2 capture on calcined dolomite has been carried out. The dolomite behavior as CO2 sorbent and its regeneration has been investigated by means of Linseis (TG-DTA) coupled with FT-IR spectrometer. Original and heat-treated dolomite has been characterized by XRF and SEM in order to detect the composition and the morphology. A simple modeling approach has been applied to the investigation of the CO2 sorption kinetic. The results of this work show good agreement between model predictions and experimental data obtained either by SEM micrographs of dolomite particles at different stages of the calcination/carbonation cycle, and by TG curves of CaO recarbonation as a function of time. (c) 2008 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.