(532ck) Effects of Particle Addition on Sonochemical Degradation of Phenol

In wastewater treatment, advanced oxidation processes (AOPs) using photocatalytic particles and ultrasound have been investigated for the degradation of hazardous organic compounds. In particular, the ultrasonic reaction field promotes the reaction even without UV irradiation when TiO₂, a photocatalytic particle, is added and is not susceptible to the shielding effect of increased particle volume, as is the case with photolysis. However, activation of the ultrasonic reaction field by the addition of particles is caused even by inert particles such as Al₂O₃, and the degradation rate constant increases in proportion to the overall surface area of the particles, and the activation mechanism of the ultrasonic reaction field by particles is not fully understood. In this study, we investigated the effects of the type and amount of particles added on the degradation rate of phenol degradation by ultrasound.

Phenol degradation using ultrasound proceeded in a pseudo-first order reaction in the presence or absence of particle addition. Although the reaction field was activated and the rate constant increased with Al₂O₃ as well as TiO₂, it was found that the activation of the reaction field was more easily enhanced with TiO₂. Also, it has been reported that the activation of the ultrasonic reaction field is proportional to the overall surface area of the added particles. However, a different phenomenon was partially obtained. It is suggested that the relationship between the size of the added particles and the resonance diameter of the ultrasound affects the activation of the reaction field.