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

Review of Heat Transfer Research for Solar Thermochemical Applications

“…The bulk kinetic reaction approach for modeling the reactor scale systems is described here. Experimental investigations of reaction kinetics are typically performed using thermogravimeters [64][65][66][67][68][69][70][71][72] or laboratory scale reactors, including fluidized beds [73][74][75], stabilized beds [76][77][78], and monolithic structured reactors [79][80][81][82][83]. Reaction kinetic modeling associated with each of these practices requires special attention to the corresponding experimental conditions.…”

“…However, for larger scale reactors, such as fluidized or stabilized beds with large reactive surface area, the species concentration gradient is significant in the flow direction, and a control volume approach combined with Eq. (3) is needed to characterize the reactor output [77].…”

“…Recently, Go et al [67] categorized the available reaction mechanisms into three groups: diffusion controlled, boundary-controlled, and random nucleation models. Since the point at which the reaction mechanism changes behavior from one model to another is not clear, Mehdizadeh et al [77] (3) is highly dependent on the temperature and moderately dependent on the concentration. For the iterative method, it can be initially assumed that the reaction is first order and by varying k(T) in Eq.…”

“…Using the new value of n, the first procedure can be repeated to find a better estimate of the activation energy. Through this process, the quality of the curve fit can be iteratively improved [77].…”

“…In a recent study, the hydrogen production for a laboratory scale iron-based magnetically stabilized porous structure (MSPS) is experimentally investigated [76,77]. It has been recently demonstrated that the MSPS can significantly enhance the production of hydrogen using a two-step nonvolatile looping process [77].…”