Modeling of a SMB-type Reactor for Hydrogen Storage by Iron Oxide with a Reversible Reaction Mechanism

Steam oxidation of iron metal which is the reverse reaction of the reduction of iron oxides as a hydrogen storage material was conducted under the condition of 673K with varied partial pressures of water vapor. The kinetic model of the steam oxidation of iron metal was expressed as the ordinary shrinking-core model with film diffusion control by experimental data obtained from thermogravimetric measurement. The apparent rate constant of steam oxidation was expressed as the Langmuir type equation against the partial pressure of water vapor. A model of a simulated moving bed-type reactor to solve the problem of over-reduction of materials was made. In our previous work (forthcoming), the kinetic model of the reduction of iron oxide with hydrogen was expressed as a shrinking-core model with reaction control, and the modeling of a simulated moving bed-type reactor was made with an irreversible reaction model. In this work, the modeling of a simulated moving bed-type reactor was achieved with the model of a reversible reaction consisting of reduction rate and oxidation rate.