Optimization of Preparation for α-Alumina by Calcination from Alumninum Hydroxide Using Response Surface Methodology

Abstract

The conditions of technique to prepare α-alumina by calcination from aluminum hydroxide were optimized using a central composite design (CCD) of response surface methodology (RSM). A quadratic equation model for field was built and effects of main factors and their corresponding relationships were obtained. The statistical analysis of the results showed that in the range studied the field of α-alumina was significantly affected by the calcination temperature and calcination time. According to results from analysis of variance (ANOVA), the value of the determination coefficient (R2=0.9890) indicates that the model was a good fit that 98.90% of the variation could be explained well by the model. The value of the adjusted determination coefficient (adj.R2=0.9811) was also very high to advocate for a high significance of the model. The optimized calcination conditions were as follows: the calcination temperature 1206.81 °C and the calcination time 2.06 h respectively. Under these conditions the field of α-alumina was 95.93%. In addition, the sample was characterized by X-ray Diffraction (XRD).