Generation of hydrogen from magnesium alloy scraps catalyzed by platinum-coated titanium net in NaCl aqueous solution

The recycling of end-of-life magnesium products is important because Mg alloy has an increasing number of uses in automotive and electronic consumer applications. Currently, however, only high-grade Mg scraps are recyclable and over half of all Mg scraps cannot be processed economically. This work proposes a new method for generating H-2 gas in NaCl aqueous solution by the hydrolysis of a secondary Mg sample made of low-grade Mg alloy scraps at 20 degrees C. A Pt-coated Ti net was used to catalyze hydrolysis between a Pt film and an Mg sample. When the Pt-coated Ti net was statically pressed on the surface of the Mg sample, the mean H2 generation rate was around 302.3 ml min(-1) (g of catalyst weight)(-1) for 1600 s. When the Pt-coated Ti net catalyst was ground onto the Mg sample surface, the rate of H2 production by the system improved significantly. The total volume of H2 generated was around 7.5 times that generated when the catalyst was statically loaded on the surface of the Mg sample. The mean H2 generation rate was around 432.4 ml min(-1) (g of catalyst)(-1) over 8100 s. The grinding of the catalyst against the surface of the sample caused the removing of the Mg(OH)2 passive layer, generating a large volume of H2. (C) 2007 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.