抄録
The sonochemical reactions occurred in the gas-liquid interface were investigated in aqueous solution of surfactants such as sodium dodecylbenzenesulfonate (DBS) and sodium dodecylsulfate (SDS), and the nonvolatile hydrophilic counpound such as sodium p-toluenesulfonate. It is well known that hydrogen atoms and OH radicals are formed by thermal decomposition of water, and the latters recombined to form H_2O_2. In the presence of various compounds as OH radical scavengers, the yields of H_2O_2 were measured as a function of their concentrations. The surfactants more effectively scavenged OH radicals than the nonvolatile hydrophilic compounds, and great depression of the yield of H_2O_2 was observed even at lower concentration. When aqueous solutions of DBS and sodium p-toluenesulfonate were sonicated, CO and CH_4, which are known to pyrolysis products of organic compound sonolysis, were formed from former but not from the latter. The result proposes that surfactant can accumulate in the interfacial region surrounding the cavitation bubble and are subjected to pyrolysis. It may be concluded that sonochemical decomposition of DBS proceeded via both OH radical reaction and thermal decomposition.
