TG/DTA/MS Study of the thermal decomposition of FeSO₄·6H₂O

Patrick Masset (1) , Jean-Yves Poinso (2) , Jean-Claude Poignet (3)

1 ASB - ASB-Aerospatiale Batteries
2 CEA Le Ripault - CEA Le Ripault
3 LEPMI - Laboratoire d'Electrochimie et de Physico-chimie des Matériaux et des Interfaces

The thermal decomposition of FeSO₄•6H₂O was studied by mass spectroscopy coupled with DTA/TG thermal analysis under inert atmosphere. On the ground of TG measurements, the mechanism of decomposition of FeSO₄•6H₂O is:
i) three dehydration steps
FeSO₄•6H₂O FeSO₄•4H₂O+2H₂O
FeSO₄•4H₂O FeSO₄•H₂O+3H₂O
FeSO₄•H₂O FeSO4+H₂O
ii) two decomposition steps
6FeSO₄ Fe₂(SO₄)₃+2Fe₂O₃+2SO₂
Fe₂(SO₄)3 Fe₂O₃+3SO₂+3/2O₂
The intermediate compound was identified as Fe₂(SO₄)₃ and the final product as the hematite Fe₂O₃.

Mots clés: DTA/TG; dehydration; FeSO4 center dot 6H(2)O; mass spectrometry

Domaines: Matériaux

Patrick Masset, Jean-Yves Poinso, Jean-Claude Poignet. TG/DTA/MS Study of the thermal decomposition of FeSO₄·6H₂O. Journal of Thermal Analysis and Calorimetry, 2006, 83 (2), pp. 457-462. ⟨10.1007/s10973-005-7267-6⟩. ⟨hal-00386403⟩