Exploration of the initial photocatalytic activity parameters of ?Fe2O3rutile for methylene blue discoloration in water through the OFAT process
Revista : Journal of Photochemistry & Photobiology A-ChemistryPáginas : 114495
Tipo de publicación : ISI Ir a publicación
Abstract
The photocatalyst response is related to experimental conditions that improve effectiveness in removing contaminants. A parameter analysis of ?Fe2O3rutile and water contaminated with methylene blue (MB) was carried out to obtain initial factors that impact reaction conditions. Moreover, the following factors were tested: the ?Fe2O3rutile load, the initial MB concentration, and the initial pH solution. These one-factor-at-a-time variations were made to explore the conditions of each variable with the other two fixed. Above all, a significant change was identified in the initial discoloration rate from 5.2 to 35.56 10-9 mol g-1 s-1, with 34 and 91% removal effectiveness, respectively. These results were achieved with an ?Fe2O3rutile load of 1.0 g L-1, an initial MB concentration of 8.0 10-6 mol L-1, and a pH of 8.8, after 540 min of irradiation. This high discoloration effectiveness with ?Fe2O3rutile had not been previously reported. The parameter that most influenced the photocatalytic activity was the initial pH solution due to the interaction of the point of zero charge of ?Fe2O3rutile and the contaminated water; the pH of the solution exceeds the isoelectric point, it causes electrostatic forces and hydrogen bonds with MB to increase its effectiveness. The combination of ?Fe2O3rutile and the removal of methylene blue in water improves adsorption on the surface of the ?Fe2O3rutile, providing the highest discoloration rate