Comprehensive assessment of leaching characteristics in electric arc furnace slag-based alkali-activated mortar

Abstract

This study investigates the leaching resistance and environmental performance of electric arc furnace slag (EAFS) as a precursor in alkali-activated materials (AAMs), contributing to sustainable construction practices and reducing reliance on conventional cement. The research employs detailed leaching analysis to evaluate the chemical stability, environmental impact, and long-term performance of EAFS-based AAMs (EFAM). Key findings reveal stable pH values in leachate samples, indicative of precursor properties and effective alkali activation, alongside increasing electrical conductivity over time due to the formation of durable ionic bonds. The release of heavy metals, such as Zn, Cu, and Cr, decreases significantly after 60 days, highlighting effective stabilization mechanisms. Distinct leaching patterns of oxyanions like arsenic and chromium, coupled with minimal leachability of elements such as molybdenum and barium, emphasize the material’s environmental safety. Additionally, calcium in the system reduces the mobility of certain elements, ensuring compliance with environmental standards. All leached metals remain below detection limits across samples, confirming the suitability of EFAM for construction applications without adverse ecological effects. This study underscores the relevance of thorough leaching analysis in validating the safety and sustainability of novel construction materials, paving the way for their broader adoption in eco-friendly construction.