Abstract
Enhancement of chemical reaction with a photocatalyst of titanium dioxide (TiO2) by ultrasonic irradiation is studied through the absorbance measurements for liberation of iodine from a KI aqueous solution as an index of oxidation reaction. It is well known as a synergetic effect that the addition of TiO2 fine particles under UV has an ability to enhance the yield in chemical reaction with OH-radical from hot spot at violent collapse of cavitation bubbles with intense ultrasound. In this study, the absorbance is measured after simultaneous irradiation of ultrasound and UV with the addition of TiO2 much less than the usual concentration by two orders of content. It is shown that, even in case of quite a little TiO2 addition where the photocatalytic effect is less, the yield is enhanced obviously in comparison with the summation in yield of independent procedure of ultrasound without TiO2 and UV with TiO2.
