Effect of calcination temperature on the structural characteristics and morphology of aluminas synthesized by the Pechini

The present work aims to synthesize alumina by Pechini method and evaluate the influence of calcination temperature on structural and morphological characteristics of the same in order to direct them to different applications. The methodology used in relation to citric acid: metal cation was 3:1 and calcination temperatures ranging 500-1200ºC in steps of 100ºC. The synthesized materials were characterized by X-ray diffraction, particle size distribution and scanning electron microscopy. The results showed that the variation of the calcination temperature altered the structure and morphology of the alumina. The samples had amorphous below the calcination temperature to 800ºC, the alumina phase appeared after calcination at 900ºC and the alpha alumina phase after 1100ºC. The increase in calcination temperature decreased the average diameter of the agglomerates of 17.79 to 13.01 µm for samples calcined at 500 and 1200ºC, respectively. The morphology, the change in calcination temperature did not change significantly the synthesized material. The particles are randomly distributed throughout the samples presenting geometry appearance of plaques in different sizes deposited on notable clusters. The features generated by the aluminas allow the application of alumina membranes, catalysis, dental implants, composites, etc.

Alumina; temperature of calcination; Pechini method