Kinetic Study for Gasification Reactions of Corncobs Char

Abstract

This study reports the carbon conversion rate calculated from the online gas analysis obtained from corncobs char gasification using carbon dioxide and water steam as reacting agent. Corncobs char is produced by the pyrolysis of corncobs in a muffle furnace at 450 °C for 45 min. The gasification tests is carried out at various temperatures 900 °C, 950 °C and 1,000 °C using carbon dioxide and water steam under isothermal conditions. The VRM (Volume Reaction Model), SCM (Shrinking Core Model) and RPM (Random Pore Model) were tested to interpret obtained experimental data. The kinetic parameters as activation energy (E) and pre-exponential (A) were determined from gas-analysis data by using the Arrhenius equation. From the results confrontation between experimental data and the results obtained from the models, it is found that RPM is more in agreement with the experimental data than the other two models. It is also obtained a values of activation energy of about 114.4 KJ/mol and pre-exponential factor 13.9 S for Ψ equal to 12.3 for carbon dioxide and, respectively, 105.5 KJ/mol and 18.3 S -1 from Ψ = 8.68 for water steam gasification.