(169f) The Degradation of Phenol in the Proposed Mist Flow Photocatalytic Reactor

Industrial wastewaters contain phenolic compounds that are toxic in low concentrations and can persist in the environment. The removal of these compounds is necessary for the prevention of pollution and the recycling of wastewater. However, traditional biological treatment for the treatment of those compounds is difficult due to the toxicity of those compounds to microorganisms. Advanced oxidation processes that involve the generation of radicals have been proposed for the degradation of phenolic compounds. The use of photocatalysts for water treatment applications has been studied for their stability, durability, and low toxicity. However, photocatalytic treatment can be limited by light irradiation conditions and mass transfer. To address these limitations, the use of mist generated by ultrasound has been proposed. Mist is small droplets suspended in air, and it provides benefits such as increased surface area and shorter light penetration distance in photocatalytic treatment. Prior investigations have explored the utilization of mist in a reactor utilizing ultraviolet and ultrasound irradiation. However, the generated was saturated on top of the liquid bulk, and the additional generated mist was not utilized. In this study, a reactor that can transport the generated mist using air flow was proposed. After transporting the generated mist, it was irradiated with UV light for the promotion of photocatalytic reactions. Using the reactor, the extent of the degradation of the model pollutant phenol was investigated in the mist droplets. The results indicate that the irradiation time of the mist droplets was shorter than the previous reactors, but the degradation of the pollutants was improved. The results provide important insight into the improvement of the irradiation conditions of the photocatalyst for promoting photocatalytic reactions.