Titanium dioxide is the most widely used white pigment and is present as a base in majority of paints used in the painting of aluminium tubes and cans. When remelting secondary aluminium painted with paint, based on titanium dioxide, it is necessary to know the effects of different melting parameters. In the case of reduction of titanium dioxide in liquid aluminium, the acceptable limit of titanium in the melt could be exceeded. The aim of the master's thesis was to investigate the influence of parameters and conditions of melt treatment, and how they affect on possible reduction of titanium dioxide in liquid aluminium. The experimental part was divided into two sections. In the first section titanium dioxide was added to the melt in the form of powder and the second section, where the secondary material painted with paint, based on titanium dioxide, was remelted. We prepared a series of samples to which we changed the melt treatment conditions, the temperature and holding time of the melt, and the amount of titanium dioxide powder added. Based on simple thermal analysis, cooling curves and characteristic temperatures were plotted, chemical composition was analysed, differential scanning calorimetry, XRD analysis of slag, optical microscopy were performed, and inclusions were analysed by scanning electron microscope and EDS analysis. Since there was no change in the chemical composition of any sample during the preparation of the first batch of samples, and no reduction in titanium dioxide, we performed an XRD analysis of the slag and tried to prove its presence there. The same happened with a series of samples made with the recycling process, where we were able to prove the presence of titanium dioxide in slag by XRD analysis and confirm that there was no reduction. It turned out that under none of the implemented conditions there was no reduction of titanium dioxide in liquid aluminium and consequently introduction of titanium into the melt.
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