Effect of thermal annealing on synthetic sodium oxalate crystals

The thermal stability of sodium oxalate (Na2C2O4) has been analyzed in the range of room temperature and 900 °C by different techniques. All of them, namely (i) environmental scanning electron microscopy (ESEM); (ii) differential-thermal analysis with simultaneous thermo-gravimetry (DTA–TG); (iii) temperature programmed decomposition mass spectrometry (TDP-MS); (iv) X-ray diffraction with heating stage (HS–XRD); (v) temperature programmed Raman spectroscopy (TP-Raman); and (vi) thermoluminescence (TL), provide information about the changes induced by thermal treatments. Thus, dehydration, decomposition, phase transition, decarbonylation, dissociation or lattice stress are some of the processes here described.