Kinetics and thermodynamics of thermal dehydration of magnesium oxalate dihydrate

The kinetics and thermodynamics of the thermal dehydration of crystalline powders of MgC₂O₄ · 2 H₂O were studied by means of thermal analyses both at constant temperatures and at linearly increasing temperatures. The dehydration of the dihydrate is regulated by one of the Avrami-Erofeyev laws. The kinetic parameters from TG at constant temperatures are in good agreement with those from TG at the lowest rate of rising temperatures. The dynamic dehydration kinetics was also examined, using DSC recorded simultaneously with TG at linearly increasing temperatures. The validity of the estimated mechanism and kinetic parameters is briefly discussed.