Kinetics of the sonophotocatalytic degradation of orange G in presence of Fe(3+).

The degradation and mineralization of orange G (OG) in aqueous solution by means of ultrasound irradiation at a frequency of 213 kHz and its combination with Fe(3+) were investigated. The effect of Fe(3+) concentration on the degradation efficiency was studied. The degradation of the dye followed first-order like kinetics under the conditions examined. A comparison study on the hybrid technique of sonophotocatalytic degradation in the presence of Fe(3+) (SonoFenton) with the individual techniques of photocatalysis and sonolysis was also performed. A slight synergistic enhancement in the degradation of the dye was observed during the sonophotocatalytic oxidation of OG using Fe(3+). The total organic carbon (TOC) measurements, carried out in order to evaluate the mineralization efficiency of OG using sonolysis, photocatalysis and sonophotocatalysis, showed a synergetic effect of combining sonolysis and photolysis.