Mineral carbonation of carbon dioxide with two dimensional interalyers of vermiculite and characterization of calcium carbonate

We successfully mineralized gaseous carbon dioxide into calcium carbonate solids by supplying calcium ions from vermiculite, a clay mineral species with an expandable lamellar structure, using a cationic exchange method. The calcium carbonate polymorphs precipitated at 273 and 333 K were characterized by means of X-ray diffraction and scanning electron microscopy. The results show that cube-like or rhombohedral calcite grains and sub-spherical polycrystalline vaterite aggregates are mixed at 273 K with a similar abundance. In contrast, spindle-shaped vaterite grains are predominant at 333 K. This polymorphic variation trend suggests that our carbon dioxide mineralization method using the cationic exchange can be interpreted as a system of calcium chloride and sodium carbonate.