Kinetics of consecutive reactions in the solid state: Thermal decomposition of oxalates.

The thermal and kinetic aspects of solid state decomposition reactions can be complex and posses a large number of parameters to investigate. The determination of the activation energies for the several intermediates in the thermal decomposition is particularly sensitive to the overlap in thermal decomposition traces. To overcome this problem we have undertaken the detailed kinetic analysis of the well-known thermal decomposition of hydrated calcium and strontium oxalates and mixtures of both. Indeed, their small difference in decomposition temperatures, from oxalate to carbonate, allowed us to simulate overlapping TGA signals and to use these data to test the validity of the experimental conditions and mathematical methods used to derive calculated kinetic values.