Solid state interactions in the systems CaO(CaCO3)-Fe2O3 and CuFe2O4-CaO

Abstract

The solid state interactions in the systems CaO(CaCO3)-Fe2O3 and CuFe2O4-CaO have been studied using X-ray diffraction analysis. The influence of the temperature on the ferrite formation process has been investigated in the range of 900-1200 oC and duration up to 360 min. It has been shown that a mixture of ferrites forms at 1000 oC and interaction of 240 min. The exchange reactions in the systems CuFe2O4-CaO and Cu0.5Zn0.5Fe2O4-CaO have been studied, too. It has been established that Ca2+ ions exchange Cu2+ and Zn2 partially and the solubility of copper and zinc in a 7 % sulfuric acid solution increases 10-15 times

Flame spheroidisation of dense and porous Ca2Fe2O5 microspheres

“…Indeed, it is noted that Ca 2 Fe 2 O 5 brownmillerite-type phase (srebrodolskite) formation can occur as a consequence of Fe 2 O 3 and CaO reaction (eqn (3)), whilst the formation of mineral srebrodolskite is in agreement with previous work on CaO:Fe 2 O 3 thermal processing. 22,24 In particular, Boyanov, 24 reporting on the formation of calcium ferrites (Ca 2 Fe 2 O 5 and CaFe 2 O 4 ) in the range of 900-1200 1C, investigated by HT-XRD, noted complete consumption of CaO:Fe 2 O 3 by 1200 1C. This balance helps to explain the presence of residual Fe 2 O 3 peaks at 1050 1C in Fig.…”

Phase transformations in CaCO3/iron oxide composite induced by thermal treatment and laser irradiation

“…Calcium ferrite can result from the reaction of CaO and the iron oxide. In the literature, this oxygen‐deficient perovskite structure can be obtained by a solid state reaction of CaO with Fe 2 O 3 calcined at 900 °C −1000 °C . Isupova et al shows that a mechanical treatment of the precursors before sintering can decrease the formation temperature of the brownmillerite.…”

Optimum Conditions for Synthesizing Fe Substituted Hibonite

“…[1][2][3] In spite that pure M-type CaFe12O19 phase does not exist in the CaO-Fe2O3 diagram, [4][5][6] the M-type phase becomes stable with the addition of a rare-earth element of lanthanum to CaFe12O19. 7,8) The optimum synthesis condition of the (Ca,La)-based M-type ferrite with the highest magnetization was recently clarified.…”