Investigation of hydrogen production reaction kinetics for an iron-silica magnetically stabilized porous structure

In this study the hydrogen production for a laboratory scale iron-based magnetically stabilized porous structure is experimentally investigated for temperature and steam superficial velocities ranging from 600 to 800 °C and 5–25 cm/s, respectively. A reaction kinetic model is proposed, and the important non-dimensional parameters describing the physical characteristics of the reactor are determined. A numerical code is developed to solve the species transport and the substrate conservation equations along the reactor in order to calibrate the kinetic model. A parametric study of the model is conceived and the activation energy, order of the reaction, and the best form of the reaction rate model are determined from experiments. The calibrated model shows very good agreements between the predicted and measured hydrogen production rates. A dimensionless parameter is introduced as the reactor effectiveness, and is utilized to find the operating conditions for which the reactor effectiveness is the highest. This highly reactive structure is very suitable for industrial applications, and the model can provide an excellent tool for designing and controlling larger scale reactors.

► The reaction kinetics of magnetically stabilized porous structure is investigated. ► The activation energy is found to be 88.29 ± 3 kJ/mol. ► The order of the reaction is found to be in the range of 1.03–1.15. ► The reactor effectiveness is introduced to characterize good reactor performance.