Waste Colored Glasses as Sintering Aid in Ceramic Tiles Production

Abstract

Bentonite, kaolin and Montmorillonite were mixed with 0%, 2%, 5% and 10% by weight additions of mixed color post consumer glass to determine their softening points. And then to determine the effects of glass addition on clay firing, Acustar tinted tempered, Acustar GL-20 and post consumer mixed were used. Six glass samples were produced; 150 micron and 5 micron tinted tempered, 150 micron and 5 micron GL-20 and 150 micron and 5 micron post consumer mix. Bentonite clay was used to mix with these glasses at 0wt%, 2wt%, 5wt%, 10wt%, 25wt% and 50wt% and 5% water was added. The resulting composite blends were then die pressed at 3200 psi to produce rectangular specimens with cross sections of 1.25” x 0.5”. Each specimen weighed approximately 2.5 grams and they were fired at 800℃, 900℃, 1000℃ and 1100℃ in a lindberg box furnace in air. The firing result showed that the addition of only a small percentage of post consumer glass lowers the melting points of clays by 50℃to 150℃. As a result of this the energy consumed to produce the clay products was reduced and the amount of reduction varied from clay to clay. Different size glass particles also resulted in considerably different effects on the clay sintering properties.