A comparative study of ethylenediamine tetraacetic acid induced gas-solid and liquid-solid accelerated carbonation for enhancement of steel slag aggregates

• DOI: 10.1016/j.conbuildmat.2023.132539
• Publication Date: 2023-07-28T02:54:05Z
• Authors: Ning Li; Cise Unluer
• Keywords: Brucite; Carbonatation; Periclase

Accelerated carbonation is an effective technique to enhance the hydration reactivity and volume stability of steel slag aggregates (SSA). However, due limitations in CO2 transport kinetics, SSA frequently carried out using pure under high pressures. In this study, 10% concentration ambient temperature pressure was employed treat SSA. To accelerate SSA, ethylenediamine tetraacetic acid (EDTA)-induced gas–solid (dry) liquid–solid (wet) processes were proposed. Effect EDTA on physical mechanical properties microstructure carbonated SSA; performance resulting concrete with a selected mix design examined. Dry prior which sprayed surface resulted denser layer consequently higher specific gravity compared uncarbonated Concrete samples involving 0.1 mol/L at 50% water absorption mass followed by curing for 24 hrs, revealed 24% increase strength 75% reduction expansion when those containing Wet during injected into SSA-EDTA solution, promoted both especially 0.2 consumption periclase enabling formation brucite. While improvement not obvious presence brucite that weakened interfacial transition zone (ITZ) concrete, further reduced Comparatively, EDTA-induced dry more required only 0.4 kg per tonne