Mineral carbonation, one of the CCU technologies, is known to have a practical CO₂ reduction effect in some countries with insufficient storage space. It is essential to secure raw materials and appropriately use carbonate after carbonation to realize mineral carbonation technology.

In this study, we attempted to immobilize CO₂ using ground solidification materials used in civil engineering construction as a raw material for mineral carbonation. Ground solidification materials generally contain a large amount of CaO, the raw material for pozzolanic reaction and ettringite formation. When applied to the ground, the solidification material is used together with water, and the hydrated CaO continuously hardens through a pozzolanic reaction to produce a stable, solidified body. Additionally, ettringite creates a more solidified body by evenly filling the space between soil particles in the ground.

To confirm the CaO content required for the reaction, component analysis of the solidification material, which is the raw material for carbonation, was conducted. In addition, the production of carbonate after carbonation was confirmed through XRD, XRF, and TGA analysis, and the amount of fixed CO₂ was calculated through this. To check the difference in strength depending on the carbonation ratio, a prototype was produced, and whether it met the standard strength (0.8 MPa or more, based on seven days of curing) was checked using a universal testing machine (UTM). This confirmed the possibility of future use in actual construction sites.

Keywords: Mineral Carbonation; Ground solidification material; Pozzolanic reaction; Ettringite; CCU.

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