International Journal of Hydrogen Energy, Vol.45, No.7, 4673-4684, 2020
Experimental study of a metal -hydrogen reactor's behavior under the action of an external magnetostatic field during absorption and desorption
The aim of this work is to experimentally study, the behavior of a metal-hydrogen reactor (MHR) subjected to the action of an external magnetostatic field, during hydrogen absorption and desorption by the LaNi5 hydride. The reactor was surrounded by a copper coil crossed by a continuous current delivered by a DC generator. In this study, the mass of the absorbed and desorbed hydrogen was measured and plotted for different initial temperatures and pressures functions of the applied magnetostatic field. The ratio of the hydrogen mass absorbed or desorbed with and without supplying a magnetostatic field was estimated after which the change in the saturation magnetization per 1 mol of desorbed hydrogen atom (Delta M-s), for the LaNi5 compound; was determined. The results demonstrated that while the increase in temperature was not beneficial for the absorption reaction, it improved the desorption process. The increase in pressure leads to an increase in the absorbed hydrogen mass. The effect of the applied magnetostatic field was observed especially for the lowest temperatures in the case of the absorption reaction. In fact, we noticed a small increase in the absorbed mass, which decreased and disappeared in the highest temperatures. It was found that the magnetostatic field had no effect on the desorption reaction for the tested fields and temperatures. The low value of Delta M-s confirmed the paramagnetic nature of the sample. Published by Elsevier Ltd on behalf of Hydrogen Energy Publications LLC.
Keywords:Metal hydride;Hydrogen absorption;Hydrogen desorption;Magnetostatic field;Equilibrium pressure