Temperature dependence on hydrogen production from hydrolysis reaction of recycled aluminum

Hydrogen (H-2) is an energy carrier capable of replacing fossil fuels without the main effect of combustion-based pollutant generation into the atmosphere. Therefore, its sustainable production is of great interest. In this research study, the effect of temperature in the reaction of hydrolysis with recycled aluminum for the H-2 production has been evaluated. The reaction was carried by using a concentrated NaOH solution, and different operating temperatures were established. According to the gas chromatography analysis, the produced H-2 has a purity of 93.33%. Accumulated H-2 production over time at different temperatures was statistically modeled with growth models (Gompertz, Logistic and Asymptotic) which showed a good fit. According to the statistical analysis, it was found that the main effect of temperature on the reaction is the increase in speed, with the highest production (727 mL) in 116 s at 50 degrees C. Nevertheless, at room temperature, the reaction efficiency was found to be 97%, obtaining 660 mL of H-2 in 268 s. The physicochemical characterization of the solid residues obtained in the reaction revealed that these are formed by micrometric agglomerates containing aluminum, sodium, and oxygen. Moreover, the main crystalline phases detected were aluminum hydroxide and sodium aluminum oxide hydrate. It is concluded that the production of H-2 from recycled aluminum at room temperature can be a viable option for the generation of clean power with lower energy consumption and financial costs than traditional technologies. [GRAPHICS]