Evolution of hydrogen from magnesium alloy scraps in citric acid-added seawater without catalyst

This work employed a mixture of low-grade Mg scraps (LGMS) and citric acid-added seawater to generate hydrogen gas. Metal catalyst was not required for accelerating the reaction of H2 generation in the Mg scraps/citric acid solution. LGMS in 20 wt% citric acid-added seawater could produce substantially higher H2 volume than the LGMS in 5 wt% citric acid-added seawater. Purity of the generated H2 was about 99% (after dehumidification). By filling H2-production reactor every 30 min with fresh seawater to which citric acid has been added, ∼70 l of hydrogen could be produced in 100 min.