Characterization of sonochemical reactors by chemical dosimetry

Irradiation of ultrasonic waves induces cavitation in a solution, and a chemical action instigated by radicals occurs. This chemical action is reported to be most efficient in the region of several hundred kilohertz frequencies. Application of sonochemistry based on ultrasonic chemical action remains at the laboratory scale and has not yet reached the industrial practical scale. In order to realize practical applications of sonochemistry, there is a need to scale-up the sonochemical reactors. For this purpose, we used a 490-kHz cylindrical sonochemical reactor that is long in the irradiation direction, and used potassium iodide (KI) dosimetry, sonochemical luminescence, and calorimetry to evaluate the sonochemical reaction efficiency and reaction field of the reactor. We performed the evaluation with the ultrasonic irradiation direction in the horizontal and vertical directions. As a result, we observed sonochemical luminescence and a rise in temperature near the reflection surface, for both the horizontal and vertical irradiation. For the horizontal irradiation, the 13 concentration was evenly distributed in the irradiation direction. Moreover, we found that the sonochemical reaction efficiency was the same for both the horizontal irradiation and the vertical irradiation. (C) 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 90(8): 1-8, 2007; Published online in Wiley InterScience (www.interscience.wiley.com).