Granulometric evaluation of continental bentonites and kaolin for ceramic applications

Increasing demand for bentonite and kaolin usage in the ceramic industry engineered this study, which focused on understanding the granulometry of some selected continental clayey materials from Botswana, Mozambique, Pakistan, Senegal, South Africa and the United States of America. The Particle Size (PS), Particle Size Distribution (PSD), modal diameter and Specific Surface Area (SSA) of the clayey materials were determined. The results depicted that all samples had particles with Euhedral Spherical Diameter (ESD) which were ≤50 μm and also contained between 11.2 and 42.5 wt. % of ≤2 μm fraction of clayey material. The modal diameters ranged from 1 to 13 μm and the SSAs were between 4 and 19 m² g^-1. These values are in conformity with those obtained by other researchers and based on their granulometric characteristics; the clayey materials were found to be suitable for use in the ceramic industry.