Heavy metal transformation and immobilization of carbonated supplementary cementitious material

Research Project, 2025 – 2027

This project aims to develop innovative carbonated supplementary cementitious materials (SCMs) from industrial waste, contributing to the reduction of CO2 emissions in the cement industry, which is a significant global emitter. Carbonated SCMs, created through the CO2 mineralization of industrial waste such as steel slag, mine tailings, and biomass ash, offer environmental benefits and enhanced cement properties. However, concerns regarding the potential leaching of hazardous heavy metals from these materials pose risks to human health and ecosystems. To address this, the project will systematically map the hazard-flow distribution of heavy metals in various types of industrial waste. Using advanced characterization techniques, it will identify the specific mineral phases that contain metals prone to leaching, providing critical insights into how heavy metals transform and stabilize during carbonation. A key objective is to develop an immobilization enhancement protocol to ensure that these materials can be safely integrated into cement applications. In addition, the project will apply a step-by-step precipitation method to selectively precipitate heavy metal carbonates, reducing their mobility and environmental impact. To support large-scale industrial implementation, the project will integrate advanced predictive tools, including deep learning, to model and predict heavy metal leaching under different environmental conditions. This predictive framework will allow for the rapid assessment of new SCMs and the optimization of carbonation processes, ensuring minimal environmental risks. By achieving these objectives, the project aligns with the Work Programme’s focus on reducing industrial waste, lowering CO2 emissions, and promoting sustainable construction materials while addressing environmental safety concerns.