Evaluation of the impact of Izmit Gulf bottom mud on the microstructure and technical properties of porcelain tiles

Abstract

Recycling waste, using new potential local raw materials, and ecological practices have become necessary in today's world. This study added Izmit Gulf bottom mud waste as a replacement for clay in porcelain tile compositions at 5%, 10%, and 15% by weight (both in its natural form and its form calcined at 1000 degrees C). The samples sintered under industrial heating at 1220 degrees C were evaluated for firing shrinkage, density, green and fired flexural strength, and water absorption values and compared with standard porcelain tiles. Phase analysis was carried out using X-ray diffraction, and microstructural characteristics were examined using a scanning electron microscope. Notably, the samples containing 10% bottom mud showed green strength twice as high as the standard and a maximum fired strength of 85 MPa. X-ray diffraction revealed the formation of quartz, mullite, and sillimanite crystals in the waste-added samples. Calcination reduced the fluxing components and adversely affected rheology, making the natural form of waste more effective. At 15% addition, porosity increased, leading to deterioration in mechanical and physical properties. The A3 composition studied here is proposed as a promising alternative for producing a more sustainable, affordable, and environmentally friendly porcelain tile product. (c) 2025 The Authors. Published by Elsevier Espana, S.L.U. on behalf of SECV. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/ by-nc-nd/4.0/).