Highly Efficient Carbon Mineralization Using Amine-Functionalized Magnetic Nanoparticle Clusters

Carbon mineralization, which transforms carbon dioxide (CO₂) into a stable form such as calcium carbonate or magnesium carbonate, has emerged as a promising technology for long-term CO₂ storage. In this study, we developed amine-functionalized magnetic nanoparticle clusters (A-MNPs), that enhance both CO₂ capture and its subsequent mineralization, by hydrothermal method and immobilization of (3-Aminopropyl)triethoxysilane (APTES). The surface of A-MNPs was covered by the APTES monolayer with approximately 100% coverage. A-MNPs expanded the surface area of CO₂ bubbles and led to amine-CO₂ coupling, improving CO₂ uptake. Subsequently, the injection of calcium chloride into the CO₂-saturated A-MNP solution resulted in carbon mineralization (i.e. CaCO₃ formation) with improved efficiency. Additionally, the shapes of CaCO₃ could be adjusted by adding anionic surfactants to the solution. Since A-MNPs can be controlled by magnetic force, they can be recovered using a magnet and reused more than 10 times without a loss in their catalytic activity, offering an efficient and sustainable method for CO₂ storage.