Caracterização e avaliação da viabilidade do calcinado de xisto retortado como pigmento inorgânico

Abstract

Due to growing ecological awareness and economic issues, the use of natural raw materials in the production of pigments is sought. In this way, the use of the calcined retorted shale becomes a potential input in the industry of inorganic pigments. The use of retorted shale as raw material in this work refers to the fact that it is a byproduct of the PETROSIX® process, currently without any attractive commercial use. The main of this work was to characterize and use the schist calcined shale and the extracted chromophore in ceramic enamels and polymers pigmentation. Through physical chemical analysis was possible to conclude that the chromophore present is hematite. This chromophore was extracted in acid solution and precipitated in alkaline medium with 10.4% recovery factor. The chromophore extracted applications in ceramic glazes presented color stability and repeatability best conditions in concentrations of 3% with a low temperature frit; it was not observed in 5% application concentrations, in high temperature frits, automotive windshield glass using calcined retorted shale. In the case of polymers application is possible to conclude the significant concentration influence of the calcined of schist shrouded on the pigmented test pieces; these presented appropriate conditions of color homogeneity and repeatability in concentrations of 3% by mass.