Calcium ferrite formation from the thermolysis of calcium tris (maleato) ferrate(III)

[摘要] For preparing calcium ferrite, calcium tris (maleato) ferrate(III) precursor was prepared by mixing aqueous solutions of iron(III) maleate, calcium maleate and maleic acid. Various physico-chemical techniques i.e. TG, DTG, DTA, Mössbauer, XRD, IR etc have been used to study the decomposition behaviour from ambient to 900°C and ferrite formation. Three consecutive decomposition steps leading to the formation of ð›�?-Fe₂O₃ and calcium carbonate have been observed at various stages of thermolysis. In the final stage the ferrite, Ca₂Fe₂O₅, is obtained as a result of solid state reaction between ð›�?-Fe₂O₃ and calcium carbonate at 788°C, a temperature much lower than for ceramic method. The results have been compared with those of the oxalate precursor.

[学科分类] 材料工程

[关键词] Ferrites;thermal decomposition;precursor technique;calcium ferrimaleate.