Non-isothermal decomposition kinetics of synthetic serrabrancaite (MnPO4 · H2O) precursor in N2 atmosphere

The thermal decomposition of synthetic serrabrancaite (MnPO4 · H2O) was studied in N2 atmosphere using TG-DTG-DTA. Thermal analysis results indicate that the decomposition occurs in two stages, which are assigned to the dehydration and the reduction processes and the final product is Mn2P2O7. X-ray powder diffraction, FT-IR and FT-Raman techniques were used for identification of the solid decomposition product. The decomposition kinetics analysis of MnPO 4 · H2O was performed under non-isothermal condition through isoconversional methods of Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira-Sunose (KAS). The dependences of activation energies on the extent of conversions are observed in the dehydration and the reduction reactions, which could be concluded the "multi-step" processes. © Akadémiai Kiadó, Budapest, Hungary 2009.