Synthesis Cordierite Materials Starting from Algerian Kaolin

Abstract

The objective of this work is to study the synthesis of the cordierite phase from Algerian kaolin known as DD kaolin. To do this, the kaolin is washed and sieved to prepare a particle size fraction <20 μ, rich in clay particles, and precipitated magnesium hydroxide is prepared to give magnesium and finally silica fume is added to the mixtures experimental, to fill the silica deficit. The weighing of the materials is carried out in such a way as to produce mixtures close to the ideal phase of the cordierite (2MgO.2Al2O3.5SiO2). The mixing is carried out in a large quantity of water with a metal stirrer at high speed. The mixture is heated during stirring until the sludge is obtained. The final drying is continued in an oven, the coarse powder obtained is finely ground in a porcelain mortar.

The results of investigations carried out by simultaneous thermal analysis (ATD-TG) show a first exothermic peak at 945 °C. which is attributed to μ-cordierite, a second exothermic peak at 1200 °C. which indicates the crystallization of μ-cordierite in Indialite, and finally an endothermic peak above 1400 °C which indicates the fusion of the indialite.

The results of investigations of the X-ray diffraction analysis on the calcined powders at high temperature, shows that only the Indialite phase is present from 1300 °C.