Enhancing mechanical properties of carbonated steel slag through surfactant-assisted CaCO3 crystallization

This study investigates the enhancement of mechanical properties in carbonated steel slag through surfactant- assisted CaCO3 crystallization. Sodium dodecyl benzene sulfonate (SDBS) was employed at various concentrations (0.1-0.4 mol/L) and temperatures (20-60 degrees C) to modulate the carbonation process. Optimal performance was achieved with 0.2 mol/L SDBS at 40 degrees C, resulting in a maximum CO2 uptake of 8.51 % and a compressive strength of 62.89 MPa, 81.66 % higher than unmodified steel slag. Characterization techniques confirmed the formation of crystalline calcite, vaterite, and aragonite, contributing to improved microstructure and strength. SDBS micelles act as templates for CaCO3 nucleation and growth, with low concentrations facilitating carbonation and high concentrations inhibiting it. This research offers new insights into surfactant-assisted crystallization for enhancing carbonated steel slag properties, paving the way for high-performance, eco-friendly building materials from industrial waste.