Optimizing hydrolysis of waste aluminium materials through temperature and pH control

Aluminium water reactions offer a promising pathway for clean hydrogen generation and energy conversion. This study experimentally investigates the effect of pH, temperature and various aluminium materials on hydrogen production using aluminium-water reactions. Five types of aluminium based materials were evaluated: aluminium powder, pellets and aluminium-based waste, like food wrap, medicine blister foil, and discarded aluminium cans. The findings demonstrate that the aluminium powder yielded the highest hydrogen production at 99.63%, followed by aluminium cans at 95.58%. In terms of reaction duration, aluminium powder exhibited the highest production rate of 56.25 mL/min at 125℃. Comparing experimental yields to the theoretical yields, aluminium powder and medicine blister foil approached the theoretical values at 100℃, whereas pellets and foil achieved near-theoretical yields at 125℃. The kinetic analysis of hydrogen gas production revealed that aluminium pellet exhibited the highest activation energy (29.96 kJ/mol) while the aluminium powder had the lowest (22.8 kJ/mol). Furthermore, the morphology and elemental composition of the by-products generated from various aluminium materials after hydrogen production were analyzed using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR). The study provides a comprehensive understanding of the structural changes and chemical interactions involved in the aluminium-water reaction, offering valuable insights for enhancing aluminium based hydrogen generation processes. © 2025 Elsevier B.V., All rights reserved.