Effect of calcination temperature on the structure and stability of natural clays from the province of San Luis

Abstract

Three natural clays obtained from soils in the Province of San Luis were calcined at different temperatures, ranging from 200 °C to 900 °C, in order to study the structural changes and stability of the resulting ceramic material. For this purpose, thermal analyzes (TGA-DSC), X-ray diffraction (XRD) and a study of resistance to disintegration in an aqueous medium were conducted. The results demonstrated that illitization of the montmorillonite phase occurs at 450 °C, and around 600 °C dihydroxylation arises and sintering of the clays begins. Finally, adequate resistance to disintegration is achieved at 700 °C.