Abstract
Successive impregnation and calcination process was performed in order to produce TiO2/perlite composites. 23-1 fractional factorial design was first applied to optimize the production conditions of TiO2/perlite photocatalysts. Seven TiO2/perlite composites (including three central point experiments) were produced by manipulating three process parameters (amount of TiO2 used in impregnation process, particle size of perlite and calcination temperature). Prepared TiO2/perlite photocatalysts were characterized by X-Ray Diffraction Spectrometer and SEM. XRD patterns indicated that anatase was the main crystalline phase for all produced samples. Degradation capacities of produced TiO2/perlite composites were investigated in methylene blue degradation process. The linear models of TiO2 loading (%) and methylene blue degradation (%) of TiO2/perlite composites were developed by regression analysis of the experimental data. As a result of analysis of variance, it was found that developed models were statistically significant with the p-value of 0.0040 and 0.0003, for TiO2 loading (%) and methylene blue degradation (%), respectively. According to the coefficient of determination (0.9821 and 0.9970 for the models of TiO2 loading and methylene blue degradation, respectively) and error analysis, developed models fit well to the experimental data. Effect of process parameters was investigated by using response surface plots. Amount of TiO2 and particle size were found as the most effective parameters on both TiO2 loading (%) and degradation efficiency (%). Calcination temperature did not affect TiO2 loading but methylene blue degradation capacity.