Effect of copper oxide on decomposition kinetics for calcium carbonate

Decomposition kinetics of calcium carbonate doped with 1.0%CuO (in mass) and the sample without doping were studied by thermogravimetric analysis-differential scanning calorimetry. The apparent activation energy of the two samples was obtained by using Coats and Redfern equation. Furthermore, the mineral phases and morphology of the sample doped with 1.0%CuO and calcined at deferent temperatures from 600°C to 1100°C for 0.5 h were analyzed by X-ray diffraction, scanning electron microscope, and energy dispersive X-ray analysis. Results show that the doping of copper oxide can decrease the decomposition temperature and apparent activation energy of calcium carbonate. The temperature and activation energy of the calcium carbonate doped with 1%CuO are lower 12°C and 10 kJ/mol respectively, compared with the reference sample without doping. The results also show that the reaction between CuO and CaO can form two intermediate compounds, CaCu₂O₃ and Ca₂CuO₃, in which minor liquid phase is formed during 1000°C to 1050°C.