Optimizing reactor structure to increase MgH2 dispersion and improve hydrolysis performance

Abstract

Hydrogen has attracted wide attention due to its high calorific value, good combustion performance, non-toxic, and green characteristics. MgH2 has obvious advantages in hydrogen storage due to its high hydrogen storage density, mild hydrolysis conditions, rich raw materials, etc. However, poor hydrolysis kinetics limits its application in hydrogen storage. Different from research on MgH2 material modification, the physical method was employed to increase the MgH2 dispersion and improve the hydrolysis kinetics. Furthermore, hydrolysis reactors, including tubular, flaky and finned units, were designed and optimized. The results indicate that enhancing the dispersion of magnesium hydride can significantly improve the hydrolysis kinetics. The use of hydrolysis reactors with highly dispersed MgH2 can effectively enhance the controllability and continuity during the hydrolysis process. This can be attributed to the reduction in the surface coating of unreacted magnesium hydride by the generated magnesium hydroxide, as well as the improved transfer performance between the fresh hydrolysis solution and solid magnesium hydride. The findings of this study can further expand the range of reactor types for magnesium hydride hydrolysis and provide new insights for designing controllable and continuous hydrolysis reactors.