Statistical optimization of process conditions for photocatalytic degradation of phenol with immobilization of nano TiO2 on perlite granules

Response surface methodology (RSM) using D-optimal design was applied to optimization of photocatalytic degradation of phenol by new composite nano-catalyst (TiO2/Perlite). Effects of seven factors (initial pH, initial phenol concentration, reaction temperature, UV irradiation time, UV light intensity, catalyst calcination temperature, and dosage of TiO2/perlite) on phenol conversion efficiency were studied and optimized by using the statistical software MODDE 8.02. On statistical analysis of the results from the experimental studies, the optimum process conditions were as follows: initial pH, 10.7; initial phenol concentration, 0.5 mM; reaction temperature, 27 degrees C; UV irradiation time, 6.5 h; UV light intensity, 250 W; catalyst calcination temperature, 600 degrees C; and TiO2/perlite dosage, 6 g/L. Analysis of variance (ANOVA) showed a high coefficient of determination (R-2) of 91.8%.