Estudo do potencial tecnológico de diferentes argilas do município de União-PI para produção de blocos cerâmicos

Abstract

The development of products for the structural ceramics industry is based on formulations involving mixtures of two or more clays, generally based only on empirical knowledge. Given this, it is important to carry out studies to arrive at an appropriate proportion between raw materials, assuming that scientific knowledge will result in a quality final product without waste. Therefore, this work aims to characterize raw materials from the municipality of União (PI) and develop formulations composed of 3 (three) clays industrially used for the production of sealing blocks and analyze their properties in comparison with the binary formulation used by the factory. The raw materials were characterized using the following techniques: energy-dispersive X-ray fluorescence (XRF), X-ray diffractometry (XRD), thermogravimetry (TG) and scanning electron microscopy (SEM). For the formulated specimens, they were analyzed through technological tests: fire loss (PF), linear shrinkage (RL), water absorption (AA), apparent porosity (PA), apparent specific mass (MEA) and tension test. rupture and flexion. The results in the diffractograms showed the presence of kaolinite, orthoclase and quartz for the three clays, the latter presenting the most intense peak. Among the three clays studied, two of them presented a moderately plasticity index, the black and red clay, while the yellow clay was weakly plastic. The clays had similar grain size curves and different grain sizes, but the yellow and black clays had similar grain sizes observed in the SEM. The macrostructural analysis of the ceramic materials showed a reddish firing color and shape stability. All specimens presented TRF values above those recommended for the production of ceramic sealing bricks. The formulations developed called F0, F1, F2.F3 and F4 presented satisfactory results regarding technological tests in relation to the standard formulation developed by the factory, making them compatible with use in industry. Formulations F1 (60% - 20% - 20%) and F4 (40% - 30% - 30%), presented the highest mechanical resistance values (19.95 MPa) and (10.65 MPa).