Effect of saponification-based treatment of palm kernel shell aggregates on the mechanical properties of palm kernel shell aggregates concrete

Abstract

This paper presents a method of treatment of Palm Kernel Shell (PKS) aggregates to remove the oil that inhibits the development of strength in PKS concrete. 13 treatments from 2 to 20 g/L concentration of solutions of potassium hydroxide were used to induce a saponification reaction with the oil present on the PKS surface. The oil is entirely removable, but the highly concentrated solution damages the aggregates’ surface. The optimum concentration to remove the oil was 10 g/L for an optimum exposure time of 12 h without affecting the PKS aggregates’ integrity and the PKS concrete’s mechanical properties. Compressive strength and a splitting tensile strength at 28 days of 20 MPa and 1.2 MPa were achieved without admixture.