Dehydrogenation kinetics of MgH2-based hydrogen storage tank at different operating temperatures and mass flow rates

The most efficient electrical production from fuel cells integrated with hydride-based hydrogen storage tanks is obtained from suitable dehydrogenation kinetics, facilitating constant flow rate of hydrogen supply for a long period of time. Dehydrogenation kinetics of hydride-based tanks depends strongly on operating temperatures and system pressures, relating to hydrogen mass flow rate (H2-FR) released from the tank. Since a cylindrical tank (96.2 mL) mounted with central heat exchanger containing TiF4-MWCNT-MgH2 (∼45 g) shows excellent de/rehydrogenation and reversibility (5.4 wt % H2 upon 20 cycles), the effects of different operating conditions (T = 300–340 °C and H2-FR = 0.6–1.0 standard L/min) on kinetic properties of this MgH2-based tank are of significant interest. Kinetic properties either rapid or steady-state desorption can be optimized by tuning the operating temperature and H2-FR simultaneously. Moreover, the performances in the axial and radial directions of the tank as well as kinetic behaviors and rate-limiting step during dehydrogenation at different temperatures and H2-FR of MgH2-based tank are investigated.