Thermal Decomposition of Some Iron(III) Chromates

Abstract

The thermal decomposition of the chromates FeOHCrO₄, KFe₃(CrO₄)₂(OH)₆, Fe₂(CrO₄)₃.H₂O and Fe₂(CrO₄)₃.3H₂O have been studied by thermal analysis and Mossbauer spectroscopy. The possible presence of Fe₂O(CrO₄)₂ as a second phase formed during the decomposition is discussed. Final products in all reactions were oxides of iron(III) and chromium(III). In addition K₂Cr₂O₇ Was present in the reaction products for KFe₃(CrO₄)₂(OH)₆.