Coal gasification studies applied to H2 production

The kinetics of the gasification of an Argentinean coal char with carbon dioxide has been studied by thermogravimetry between 1073 and 1223 K. The starting temperature for the reaction of the char with carbon dioxide is determined at about 873 K. The influence of gaseous flow rate, sample mass, temperature and carbon dioxide partial pressure in the reaction rate is analyzed. The conditions under which the progress of reaction is controlled by chemical reaction are established. In those conditions, an activation energy of 45.6 kcal mol(-1) was obtained with an isoconversional method. Regarding the effect of partial pressure of CO2, the gasifications were found to be of first order reaction for CO2 for partial pressures of CO2 up to 61 kPa. In addition, a Langmuir-Hinshelwood type equation fits the experimental data for whole range of pressures to a certain extent. (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.