Evaluation of the chemical and thermo-physical properties of locally aggregated kaolin-based refractory materials

Abstract

There is a continuous demand for refractory materials to meet the increasing expansion of industries and plants. Local clay materials are being explored to augment the inadequate supply of refractory materials. This study therefore evaluated the suitability of locally aggregated kaolin as refractory material. The kaolin was aggregated from Ipinsa kaolin, termite hill materials and bentonite in the ratio 5:4:1 by mass. Chemical analysis carried out on the materials using Proton Induced X-ray Emission (PIXE) Equipment revealed that the kaolin aggregate had a composition of 37.22% alumina (Al2O3) and 51.93% silica (SiO2). The Ipinsa kaolin comprised Al2O3 at 43.05% and SiO2 53.91%, termite hill material (Al2O3 22.69%, SiO2 58.83%) and bentonite had 23.10% Al2O3 and 55.40% SiO2. It shows that Ipinsa kaolin can be used for refractory materials in furnaces, kilns and stoves while the aggregated clay can be used in applications requiring more superior refractory properties. The thermo-physical analysis of the aggregated clay revealed a bulk density of 1.84 g/cm3, apparent porosity 31.54%, linear shrinkage 4.00%, thermal shock resistance 40+ and refactoriness 1900 oC. The refractoriness indicated that the aggregated clay is also suitable for use as ceramic fibre within the temperature range of 1800 and 2000 oC.