Ceramic Properties of Alumina and Alumina-Mullite Pressed Bodies Based on Al-rich Anodising Sludge

摘要

Alumina and alumina-mullite based refractory ceramic materials were produced from formulations based on an industrial Al-rich sludge derived from the wastewater treatment of the aluminium anodising process. Other ceramic raw materials like diatomite was also added, which can be consider as a by-product. Cylindrical samples processed by uniaxial dry pressing were sintered at different temperatures (between 1400-1650°C, 1 hour soaking) to study the ceramic properties evolution. The performance of fired materials was evaluated (firing shrinkage, water absorption, bending strength, thermal expansion coefficient, refractoriness and SEM microstructure) and demonstrated that optimal properties were obtained at 1650°C for alumina and 1450°C for alumina-mullite.