Use of Fe2O3-TiO2 in solar photo-Fenton process for the phenol degradation

Abstract

In this work a Fe 2 O 3 -TiO 2 catalyst, at the proportion 60:40 (%mass), was produced using a modified Pechini method. The catalyst was characterized and used in the degradation of phenol in aqueous solution through a solar photo-Fenton reaction. Experiments were performed varying the concentration of H 2 O 2 , catalyst, phenol, and pH of the aqueous solution, in order to determine the reaction rate and propose a mechanism. Characterization showed the presence of Fe 2 O 3 and anatase and rutile phases of TiO 2 . Pseudobrookite (Fe 2 TiO 5 ) was also found in the material. The Fe 2 O 3 -TiO 2 catalyst presented higher efficiency (90% of phenol removal) and degradation rate than the two isolated oxides in the process photo-Fenton heterogenous in optimum conditions. The proposed mechanism shows that the union of the two oxides, Fe 2 O 3 and TiO 2 , facilitates the reduction and oxidation reactions of Fe + 2 /Fe + 3 and Ti +4 /Ti +3 , increasing the amount of surface OH groups and consequently the catalytic activity.