Synthesis of γ-Fe 2O 3 by thermal decomposition of FeC 4H 2O 4 · [formula omitted]H 2O. part II

Abstract

Thermal decomposition of ferrous fumarate half hydrate, FeC 4H 2O 4. 1 2 H 2O, has been investigated using direct current electrical conductivity, thermal analysis (simultaneous TGA, DTA and DTG), X-ray powder diffraction, infrared spectroscopy and gas chromatography techniques in static air, dynamic dry nitrogen and dynamic air. The isothermal decomposition study of FeC 4H 2O 4· 1 2 H 2O under different temperature ranges in all the above-mentioned atmospheres revealed the formation of anhydrous complex before its oxidative decomposition to α-Fe 2O 3 with the probable formation of intermediates of FeO, Fe 3O 4 and -γ-Fe 2O 3 along with anhydrous complex. Definite experimental conditions have been determined for the formation of γ-Fe 2O 3 in dynamic air containing water vapour by the use of direct current electrical conductivity measurements. γ-Fe 2O 3, thus obtained, has been characterized by X-ray diffraction, scanning electron microscopy, magnetic hysteresis measurements and Mossbauer spectroscopy.