CARACTERIZACIÓN DEL SISTEMA BINARIO DE RESIDUO CERÁMICO Y METACAOLÍN ALCALI- ACTIVADO

The red ceramic industry generates a substantial amount of solid waste, which can be reutilized in the construction sector, contributing to the reduction of natural resource consumption and CO₂ emissions from the Portland cement industry. However, the use of red ceramic waste as a precursor for alkali-activated materials remains insufficiently investigated. This study aimed to evaluate a binary mixture of red ceramic waste (RCW) and metakaolin (MK) for the production of alkali-activated cements. Four pastes with varying RCW and MK proportions were prepared. In the fresh state, mini-slump, setting time and bulk density tests were performed. In the hardened state, compressive strength was assessed at 7, 28, and 91 days, and water absorption was measured. Finally, scanning electron microscopy (SEM) analysis was conducted. The paste with 100% RCW exhibited the greatest spread (94.5 mm), while the mixture containing 75% MK and 25% RCW achieved the highest compressive strength, reaching 42.79 MPa at 7 days. SEM analysis revealed the formation of binding gels, indicating effective geopolymerization. These findings confirm the feasibility of producing alkali-activated cements from RCW and MK for cementitious paste applications.