Synthesis of Mesoporous CaCO₃ Powder using Natural Limestone as Ca Ion Source with Solution Mixing Method

In this study, the CaCO₃ powder has successfully been synthesized by mixing CaCl₂ derived from natural limestone and Na₂CO₃ in the same molar ratio. The mixing process of two solutions was performed by employing the molar contents of 0.25, 0.5, 0.75 and 1 M at varying temperatures of 35, 50 and 80°C. The produced CaCO₃ microparticles were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and Brunauer-Emmett-Teller (BET). The highest content of vaterite phase of the samples is around 96 wt%, resulted from the process using solution of 0.25 M at 35°C. All the samples prepared show mesoporous solids with pore sizes of 3-4 nm and specific surface area of 81-90 m²/g.