Electrochemical analysis of EAF slag-cement hydration and role of TIPA and glycine

This study employs electrochemical analysis using alternating current impedance spectroscopy to investigate electric arc furnace slag (EAF) slag-cement hydration kinetics through organic ligand coordination with triisopropanolamine (TIPA) and glycine (Gly) in Portland cement blends containing carbonated and non-carbonated EAF. The electrochemical monitoring was correlated with calorimetry, thermogravimetric analysis, X-ray diffraction, setting measurements, and electrical conductivity to examine coordinating effects on hydration behavior. Results demonstrated that organic ligand coordination significantly influences hydration kinetics, with carbonated mineral phases showing greater electrochemical response than non-carbonated slag. TIPA and glycine coordination enhanced fluidity, accelerated setting time, increased compressive strength, and improved hydration efficiency by promoting phase transformation into calcium silicate hydrate. Electrochemical analysis revealed that ligand affects dissolution kinetics, phase formation, and microstructure development, influenced by EAF slag type. Impedance spectroscopy effectively monitored changes in electrical conductivity during hydration, correlating with microstructure resistivity and network connectivity evolution. This electrochemical approach highlights the complementary roles of impedance spectroscopy and calorimetry in monitoring organic ligand effects on cement hydration kinetics.