Chemical Transformations as a Tool for Controlling the Properties of Calcium Carbonate Powder

摘要

Calcium carbonate CaCO3(calcite) powder with 100 - 200 nm size particles with nearly isometric shape was obtained by heat-treating at 600 degrees C a product synthesized from a 2 M solution of citric acid H3C6H5O7 center dot H2O and commercial calcium carbonate CaCO3(calcite) powder with 1 - 4 mu m size prismatic particles. The sequence of chemical transformations CaCO3 -> CaC6H6O7 center dot 3H(2)O/Ca-3(C6H5O7)(2)-> 4H(2)O -> CaCO(3)makes it possible to change the properties (size and shape) of the particles of calcium carbonate CaCO3. Thanks to these properties the obtained highly dispersed calcite CaCO(3)powder can be recommended as a filler for obtaining unique composites with inorganic (glass, ceramic, cement) or polymer matrices.