Abstract
Hydrogen peroxide is useful material for industry. It ia known that this material is produced by sonolysis. In this presentation, the possibility of sonolysis for industrial use is discussed. Sonolysis of water was carried out in various conditions. Hydrogen peroxide was obtained together with hydrogen under argon atmosphere. The production rate of H_2O_2 was 46 μmol / h(1.6mg / h). The effects of temperature, atmospheric gas and etc. were examined. No temperature effect was observed up to 25℃. In the high temperature region(>35℃), however, H_2O_2 production rate was decreased with increasing temperature. In air-saturated sample, H_2O_2 could not be detected in these experimental conditions. In order to obtain H_2O_2 from seawater by sonolysis, effects of presence of NaCl in the solution on production rates of products were examined. The amounts of products depended on the concentration of NaCl in the solution. The gradient for H_2O_2 was larger than that for H_2. The yields of H_2O_2, however, changed gradually at low concentration like seawater. Thus, the decomposion of seawater to H_2O_2 is expected to be accomplished using sonochemical reaction. The author also discussed about H_2O_2 decomposition by photocatalytic reaction. Photocatalytic reaction of H_2O_2 aqueous solution was performed using TiO_2 photocatlayst and 500-W Xenon lamp. Hydrogen peroxide in the solution was reduced obviously and off cource oxygen was produced stoichiometrically. Thus, it is confirmed that photocatalytic reaction is suitable for decomposition of H_2O_2.
