Thermal decomposition of iron(III) oxalates

Abstract

The thermal decomposition of iron(III) oxalates to iron(II) and CO 2 has been studied and a mechanism of the decomposition of iron(III) monoxalate in aqueous solution has been suggested. The monoxalate complex has been shown to decompose at 75°C by a hydrogen ion dependent mechanism. Furthermore, FeC 2O 4 + forms a labile polymeric species when its concentration exceeds 10 −2 M. The polymeric species is probably a trimer and is relatively inert to thermal decomposition. The trisoxalato iron(III) complex, in contrast to FeC 2O 4 +, does not undergo measurable thermal decomposition at 75°C, regardless of the hydrogen ion concentration.