Preparation of Sintered Glass-Ceramic from CRT Glass and Red Gypsum Wastes for Tiling Application

Abstract

This study aims to prepare sintered glass-ceramic (SGC) from a combination of cathode ray tube glass and red gypsum wastes specifically for tiling application. Bentonite clay which acted as a binder was also added to the prepared formulation. The starting materials were milled individually, mixed and compacted into button shape by using a uniaxial hydraulic press machine. The effects of sintering temperature and red gypsum content on the physical- mechanical properties and crystallization behaviour were investigated. The test results revealed that the glass-ceramic sintered at 850°C with 20 wt.% of red gypsum gave the best combination of physical-mechanical properties. Modulus of rupture and linear shrinkage were measured at 33.75 MPa and 6.47 %, respectively. Water absorption was low enough and recorded at 0.4759 % while the density was measured at 2.6638 g/cm3. The results also discovered that increasing red gypsum content by 10 wt.% and sintered at similar temperature deteriorated the quality of the glass-ceramic. Therefore, this particular sintered glass-ceramic has the potential to be used as outdoor walkway tile or brick owing to the high physical-mechanical properties, colour suitability as well as low production cost.