On the use of Afyon clay in Ukrainian clay-free compositions for porcelain tile manufacture

The conflict in Ukraine has meant that the supply of ball clay from this country has been cut off, giving rise to a serious setback for the manufacture of porcelain tile, as this raw material was a basic component for the formulation of this type of ceramic tile. This work proposes the use of a clay from the Afyon area in Turkey as an alternative, which is formed by a complex mixture of clay and non-clay minerals. In the first part of the study, a complete characterisation of the clay has been carried out, comparing it with a standard Ukrainian clay. In a second part, a composition in which Afyon clay is the main clay component has been formulated and characterised in comparison with a standard composition formulated with Ukrainian clays. Overall, the results show that, although some properties for Afyon clay differ from those for Ukrainian clays, the behaviour of the proposed composition in the different stages of the process, milling/deflocculation, pressing and firing, is similar to that of the standard composition, thus adapting it to the requirements of industrial practice. This provides a feasible alternative way of replacing Ukrainian ball clays.