CENTRO DE TECNOLOGIA DE RECURSOS MINERALES Y CERAMICA
Unidad Ejecutora - UE
Extended and local structural description of a kaolinitic clay, its fired ceramics and intermediates: An XRD and XANES analysis
L. ANDRINI; G. SUÁREZ; N.M. RENDTORFF; M.S. CONCONI; E.F. AGLIETTI; M.R. GAUNA; F.G. REQUEJO
APPLIED CLAY SCIENCE
ELSEVIER SCIENCE BV
Lugar: Amsterdam; Año: 2016 vol. 124 p. 39 - 45
The thermal transformations processes of kaolinite (K) in kaolinitic clays is knownto consist of a dehydroxylationinto metakaolin (MK) at ≈600 °C, followed by the formation of a spinel type aluminosilicate (SAS) at≈980 °C,and finally the development of mullite (M) at higher temperatures (1200?1300 °C).The structural characterization of thesematerials is generally based on X-ray diffraction (XRD) studies,where theXRD features of K and M are well defined due to their crystalline nature, but as consequence of the low crystallinityof MK and SAS, the precise characterization of these phases is not possible using this technique.In this study the nature of aluminum atoms in the different materials obtained by thermal treatments of a kaoliniteis investigated using Al K-XANES and compared with other well-known aluminum containing materials.XRD and SEM characterization were also carried out.The results confirm the potentiality of this synchrotron based techniques for the characterization of natural materialsand ceramics especially with low crystallinity. Particularly the mullite aluminums Al K-XANES spectrawere not reported before.