Evaluation of a new hydrogen generating system: Ni-rich magnesium alloy catalyzed by platinum wire in sodium chloride solutio

Abstract

Fuel cells are often seen as a long-term solution to environmental problems such as CO2: emission associated with transportation. To ensure long-term sustainability and the supply of fuel, new renewable of hydrogen (H2) generator have to be introduced. In this study, Ni-rich AZ91D magnesium alloy ingot, which was considered as waste material, was used as a H2 generator in sodium chloride (NaCl) solution with catalyst. The chemical reaction Mg + H2O → H2 + Mg(OH)2 occurred in NaCl aqueous solution. The H2 evolution rate depended on the solution's temperature (25 or 70°C), length of catalyst (0.9 or 1.8m) and the concentration of NaCl solution (5 or 10 mass%). The H2 evolution rate increased with increasing the solution's temperature. The catalyst (Pt wire) could significantly improve the H2 generation rate. In addition, the by-product of this method is Mg(OH)2, a non-toxic chemical compound which is usually used as flame retardant. © 2005 The Japan Institute of Metals.