Effect of waste PET on the structural properties of burnt bricks

Abstract

Polyethylene terephthalate (PET) is commonly used for packaging of different products because of its resistance to chemical attack and environmental degradation, but the proper disposal of this nonbiodegradable material has been a major challenge. This research investigated the reuse of this material as addition to clay in fired bricks, PET was mix with lateritic clay at 0, 5, 10, 15 and 20%. The bricks were fired in a kiln to about 900 °C for 48 h, after which the samples were tested for water absorption, firing shrinkage, density and mechanical tests. The result revealed that the 15 and 20% brick samples disintegrated at high temperature, while the lower percentage samples were deformed at their edges. The 0, 5 and 10% samples gave a compressive strength results of 5.15, 2.30 and 0.85 N/mm2 respectively, while the modulus of rupture values are 13.20, 11.96, 8.53 N/mm2 respectively. Water absorption results for the three samples were 10.29, 9.43, and 6.57% respectively and all are within the acceptable limits. This work concluded that less than 5% PET can be used in fired bricks under controlled conditions.