Mechanochemical activation for transforming low-reactive industrial by-products to supplementary cementitious materials

Although vast quantities of industrial by-products are generated globally, a significant portion remains underutilized due to their inherent low reactivity. This paper investigates mechanochemical activation using alkanolamines as a promising strategy to valorize Blast Furnace Slag (BFS), Bottom Ash (BA), Steel Slag (SS), and Ferronickel Slag (FNS) into low-carbon supplementary cementitious materials (SCMs). A comprehensive analysis of these four distinct by-products revealed that alkanolamine addition during the grinding process offers dual benefits: (1) physical particle size refinement and (2) chemical reactivity activation. While an optimal dosage enhanced grinding efficiency and fineness, excessive addition was found to induce particle agglomeration. Alkanolamines enhanced the reactivity of the by-products and altered the hydration kinetics of clinker phases. These mechanisms resulted in an improvements in the compressive strength of the blended systems. Overall, mechanochemical activation with alkanolamines demonstrates strong potential for transforming low-reactive industrial by-products into effective construction materials.