PARTIAL DECOMPOSITION OF DOLOMITE IN CO2.

Article abstract of DOI:10.1016/0022-4596(80)90118-8

Thermal decomposition of dolomite into CaCO//3 and MgO under CO//2 was investigated by isothermal kinetic measurements, X-ray diffraction analysis, and electron diffraction. The decomposition was described as an interfacial reaction. Crystalline CaCO//3 is formed in an extremely orientated state even if the temperature is higher than the decomposition temperature of calcite, at least at the earlier stage of the decomposition. The crystallites of MgO grow with time and temperature, while the grain size of CaCO//3 remains constant during the isothermal decomposition. The CaCO//3 crystallite size is minimal at about 750 degree C. The classical theories of the mechanism of the formation of CaCO//3 from dolomite were reexamined, and a direct formation theory was suggested on the basis of the results of X-ray analysis.