Non-isothermal kinetics and characterization studies for the decomposition course of CuC2O4–CdC2O4 mixture in air

DTA–TG experiment of CuC2O4–CdC2O4·3H2O (1:1 mol ratios) mixture in air shows that the mixture was completely decomposed to CuO–CdO mixture through three well-defined steps. Intermediate decomposition products as well as the final products were characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. XRD experiments show the absence of any formed solid solution even by raising the calcination temperature from 400 to 800 °C. The increase in the intensity of the diffraction lines by raising the temperature can be attributed to the grain growth of the decomposition products as revealed by SEM and nitrogen adsorption isotherm experiments. Kinetic analysis of the oxalate decomposition steps according to the composite integral method showed that the decomposition is best described by the Avrami–Erofeev equation (A2) characteristic of the solid-state nucleation growth mechanism. The activation parameters were then calculated and discussed.