Differential scanning calorimetry and Mössbauer effect studies of the thermal decomposition of hydrous ferrous oxalate in hydrogen

The thermal decomposition process of hydrous ferrous oxalate and its solid decomposition products in reducing H2 atmosphere are studied with differential scanning calorimetry (DSC) and Mössbauer effect. The results indicate that the thermal decomposition of FeC2O4 · 2 H2O in hydrogen is similar to that in an inert atmosphere. The dehydration and the decomposition are two processes quite separate as regards temperature, the initial solid decomposition product is wüstite which then transforms into magnetite and α-Fe. A small amount of iron carbide is observed among the decomposition products. The oxide and the carbide in the solid are reduced to α-Fe by hydrogen at about 415 °C.