Estudo da amorfização do caulim para aplicação como material pozolânico

Abstract

Among the clay minerals widely studied and applied in the large area of ceramic materials and other areas, kaolinite stands out due to its characteristics and technological performance. The State of Rio Grande do Norte has great potential in the exploration of this mineral, where the main form of extraction is the mining. The kaolin of this region, is characterized as of primary interperizada origin, due to its formation and local characteristics, differentiating it of the Kaolins of other regions. For this, the obtained kaolin was submitted to a thermal treatment, where a was verified a gradual amorphization was found of the crystalline structure characteristic of the material. By obtaining the amorphous form in the laboratory, also called metacaulinite, it was possible to carry out an investigation on the pozolanic characteristics compared to other materials already consolidated in the market. Thus the objective of this work Is to investigate the amorphization of industrial kaolin, coming from the pegmatitic region of Seridó RN, and to compare its pozzolanic activity with a commercially used metakaolin. For this, we used the techniques of fluorescence X-ray (XRF); X-ray diffraction (XRD); Thermogravimetric Analysis (TG); Differential Thermal Analysis (DTA); Scanning Electron Microscopy (SEM); Laser Granulometry; Specific Mass and Pozzolanic Activity Index with Cal. After characterization, it can be observed that metakaolin from the study region It has good chemical and mineralogical characteristics, with a good degree of amorphization at low temperatures and distribution close to the commercial material analyzed. From the result of pozzolanic activity the metakaolin obtained in the laboratory, presented a great potential in the formation of the hydrated phases, being of great importance in the area of cementation, among others.