Use of E-Waste in Metakaolin Blended Cement Concrete for Sustainable Construction

Abstract

This paper investigates the use of non-metallic portion (NMP) reclaimed from e-waste (i.e., waste printed circuit board—PCB) as replacement of natural sand in the blended cement concrete by using Metakaolin (MK) as supplementary cementitious material for its effect on the mechanical, durability, microstructural, and mineralogical properties of concrete. It was found that the blended mixes containing NMP and MK outperformed the control mix. With the addition of 10% NMP and 10% MK, the maximum compressive strength was obtained, with the splitting tensile and flexural strength following the same trend. The performance of the mixes was lowered above 10% replacement levels, although it was still better than the control mixture. When compared to other mixes, 10% NMP and 10% MK concrete had the lowest sorptivity and water absorption values, as well as the highest resistance to chloride-ion penetration. FESEM was used to confirm the results, and then XRD was used to determine the elemental classification. This study lays the groundwork for a long-term strategy for utilising NMP and MK as extremely effective concrete additives.