Recycling of Ceramic Wastes for the Production of High Performance Mullite Refractories

Abstract

This work aims at benefit from the huge quantities of the ceramic wastes in KSA through recycling them to produce mullite-based refractories with expected outstanding properties. Because the ceramic wastes are mainly aluminosilicate, bauxite as a source of aluminum oxide is added to obtain mullite based refractory ceramics. The mixes containing different proportions of ceramics waste and raw bauxite were well mixed then shaped into cylindrical bodies using a compressing machine. After drying at 110 °C the obtained bodies were fired at 1500 °C. The phase compositions of the fired samples were followed using X-Ray diffraction technique (XRD). The microstructure of some selected samples was depicted using scanning electron microscope, spot analysis of some selected crystals was carried through energy dispersive x-ray technique. Densification parameters, mechanical as well as refractory properties of the fired samples were tested according to the International Standards. Up to 40 wt.% of ceramic waste could be consumed for production of high quality mullite-based refractories through mixing with 60 wt.% raw bauxite which decrease the beneficial problems resulting from the accumulation of ceramic waste material. The relatively higher mullite content with recognized mechanical and refractory properties reflects its properties on such mix which enable its use at high temperature and various engineering applications.