Hydrogen production by aluminium corrosion: experimental investigation and mathematical modelling

Abstract

Abstract. The search for new energy sources has been a great focus lately because of concerns about climate change caused mainly by fossil fuels gas emissions. The hydrogen is a promising energy source due its clean and high energy combustion. However, the major drawbacks to use hydrogen are the difficulty of formation, transportation and storage. The objective of this work is the study of hydrogen formation by aluminium reaction with water by using strong alkalis as catalysts (NaOH and KOH), and the development of a mathematical model that accounts the evolution of hydrogen at each time. Different alkali concentrations were used (1, 1.5, 2, 2.5 and 3 mol . L -1 ). The reactions were carried out with aluminum in different samples: foils, plates with 0.5 mm and 1 mm width each. The range of temperatures studied was: 295, 305, 315 and 325 K for foils and 0.5 mm plates; 315, 325, 335 and 345 K for 1 mm plates. The results show ed a strong dependence of the reaction rate on the temperature, alkali concentration and shape of the samples. The model predictions of hydrogen formation agreed with the experimental data of volume versus time, as well as the peaks observed in the reaction rates.

Hydrogen Generation from Aluminum Corrosion in Aqueous Solutions

“…Aluminum samples are obtained from recycled aluminum cans. The H 2 generation rate is also mathematically fitted with a semi-empirical equation derived by Porciuncula et al (5). Our tested results show that almost no hydrogen generated in acidic or in neutral solutions.…”

“…The volume of H 2 generated can be estimated by equation [2]. It was derived by Porciuncula et al (5) and was used to fit our experimental data. Their model assumed that the hydrogen generation rate is determined by the mass transfer rate of hydroxide on the aluminum surface.…”