CaAl _(12)O _(19) was synthesised using three different precursors: (a) a polyesteric type precursor resulted from the traditional Pechini method; (b) a polyesteric type precursor resulted from the reaction between citric acid and calcium and aluminum nitrates; and (c) a polymeric type precursor resulted from the reaction between acrylic acid and calcium an aluminum nitrates. The thermal behavior of the three precursors used in the CaAl _(12)O _(19) synthesis was monitored to underline the thermal effects associated to the CaAl _(12)O _(19) formation. Thermal analyses performed on precursors do not reveal clear differences regarding the thermal effects assigned to calcium aluminates formation, at temperatures over 800 °C. In contrast, thermal analysis of samples pre-fired at 200 °C, and especially at 600 °C, show clear differences between samples obtained in different ways. It is noted that in samples obtained from acrylic acid and nitrates, and citric acid and nitrates, CA _6 is practically single phase after calcination at 1,200 °C. However, in the sample obtained from citric acid, ethylene glycol, and nitrates, calcined at 1,200 °C, CA _6 is present along with CA _2 and α-Al _2O _3.
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