Hydrogen production from palm kernel shell: Kinetic modeling and simulation

The hydrogen production process from palm kernel shell (PKS) is modeled and simulated by a steady-state gasification system using Aspen PLUS (R). The kinetic parameters of the gasification are determined by employing thermogravimetric analysis (TG/DTG) using two gasifying agents (CO2 and steam) and applying three semi-empirical kinetic models to interpret the experimental results (linear model, grain model, and volumetric model). The process was subjected to different temperatures (750-950 degrees C) and different compositions of the steam/biomass ratio (S/B) (0-2.5). It is obtained that the linear model and the grain model have the best R-2 with the gasification results of the PKS with steam (0.966) and CO2 (0.965), respectively. The steam reaction kinetic parameters obtained were E = 125.79KJ/mol and A = 26.23 s(-1), and for the reaction with CO2, they were E = 99.87 KJ/mol and A = 6.3 s(-1). The production yield of H-2 (109 g H-2/PKS kg) is reached at the highest temperature (950 degrees C) and the lowest S/B ratio (0). It is concluded that the model can predict with greater precision the hydrogen composition in the syngas, with a 0.135 mean square error, compared to other authors that present a 0.282 mean square error. (c) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.