Use of borosilicate glass waste in ceramic formulation for porcelain tiles
porcelain stoneware; processing; waste; borosilicate; ceramic
The present study addresses the development of porcelain ceramic bodies with the addition of boron-rich glass waste as a potential alternative flux to feldspar, a commonly used mineral flux. The use of waste materials as raw materials for industrial products promotes sustainability by reducing pollutant emissions and preserving mineral deposits. The methodology began with the structural, chemical, and particle size characterization of the raw materials. The material processing started from powders, with the starting materials undergoing wet milling, followed by oven drying. Afterward, the material was moistened to about 8% and manually granulated. It was then subjected to uniaxial pressing, oven drying, and sintering using a fast-firing cycle lasting approximately 60 minutes. Subsequently, technological characterizations (water absorption, Archimedes density, apparent porosity, linear firing shrinkage, and loss on ignition) were performed to evaluate the characteristics of the obtained product, as well as its compliance with ISO 13006. Additionally, X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses were conducted to assess phase changes during the firing process and to examine the material’s microstructure. Moreover, a polishing test was carried out to simulate the industrial process and evaluate changes in surface gloss. The results clearly showed that the incorporation of borosilicate glass waste effectively promoted liquid phase formation during sintering and accelerated microstructural development. Furthermore, for the same polishing route, the formulations containing glass achieved higher gloss levels compared to the formulation without waste.