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This paper aimed at studying the effect of magnesium concentration in molten aluminum produced from beverage cans on the process of aluminothermic reduction of Mn2O3 particles obtained from the cathodes of discharged alkaline batteries. The experimental results were analyzed by using thermodynamic fundamentals and kinetic modeling, while the characterization of the reaction products obtained allowed the mechanism of the process to be described. It was found that the addition of magnesium improves the wettability of solid particles by molten aluminum, thus increasing the reaction and its subsequent incorporation into the molten aluminum solution of Mn released from the reduction reaction. This work was carried out using several initial magnesium concentrations; 1.0, 2.0, 3.0, and 4.0 wt %, under a constant temperature of 1073 K, a constant treatment time of 240 min, and a constant agitation speed of 200 rpm. The results show that the higher the initial magnesium concentration in the molten alloy, the higher the speed of the chemical reduction reaction of the Mn2O3 particles.

This paper presents and discusses a methodology implemented to study the process of the preparation of aluminium alloy foams using the alloy A-242, beginning from the recycling of secondary aluminium obtained from beverage cans. The foams are prepared by a melting process by adding 0.50 wt.% calcium to the A-242 aluminium alloy with the aim to change its viscosity in the molten state. To obtain the foam, titanium hydride is added in different concentrations (0.50 wt.%, 0.75 wt.%, and 1.00 wt.%) and at different temperatures (923, 948 K, and 973 K) while the foaming time is kept constant at 30 s. For a set of experimental parameter values, aluminium alloy foams with the average relative density of 0.12 were obtained and had an 88.22% average porosity. In this way, it is possible to state that the preparation of aluminium alloy foams A-242 processed from the recycling of cans is possible, with characteristics and properties similar to those obtained using commercial-purity metals.

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In this work, the experimental results obtained during the preparation of Al-Ni and Al-Ni-Mg alloys using the aluminothermic reduction of NiO by submerged powder injection, assisted with mechanical agitation are presented and discussed. The analyzed variables were melt temperature, agitation speed, and initial magnesium concentration in the molten alloy. For some of the experiments performed, it was found that the Ni concentration increased from 0 to about 3 wt-% after 90 min of treatment at constant temperature and constant agitation speed. In order to determine the values of the kinetic parameters of interest, such as the activation energy and the rate constants, the values of the results obtained were fitted to the kinetic formulae available. Moreover, the kinetics of the reaction were found to be governed by the diffusion of Al and Mg to the NiO boundary layer, where MgAl2O4 or Al2O3 were formed as the main reaction products. Finally, from a thermodynamic study of the system, the main reactions that took place are explained.

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