Sustainable gypsum binders reinforced with industrial and bio-waste additives

This study aims to improve the mechanical strength, water resistance, and setting behavior of gypsum binders by adding industrial and agricultural waste. This study investigated the effects of ground orange peel powder, sodium silicate solution, and reactive silica on the functionality of gypsum composites intended for resource-efficient construction applications. Reactive silica (5-10%), GOPP (0-2%), and 20% sodium silicate solutions were added in different amounts to create nine mixtures. The compressive and flexural strengths, water absorption, and setting times were assessed. Scanning electron microscopy was used to monitor the microstructural development and comprehend the interactions between the additives and the gypsum matrix. The results showed that the ideal mixture (G7) consisting of 10% reactive silica, 20% sodium silicate solution, and 1% GOPP had a compressive strength of 16.9 MPa, flexural strength of 2.35 MPa, and low water absorption value of 5.41%. The GOPP successfully postponed the setting, enabling extended matrix densification and C-S-H formation. SEM analysis verified that the modified samples yielded better internal cohesion and lower porosity. This study presents a novel approach that combines organic and inorganic waste materials to enhance gypsum performance. GOPP offer waste-derived set-retarding qualities, in contrast to conventional chemical additives. The suggested process shows how gypsum properties can be improved using waste materials produced by various industries and agriculture.