Effect of hydrogen peroxide on the decomposition of monochlorophenols by sonolysis in aqueous solution.

The decomposition rates of several monochlorophenol by sonolysis were enhanced by the presence of hydrogen peroxide. An optimum concentration of hydrogen peroxide was observed for achieving maximum sonolysis rate of monochlorophenol. The decomposition rates of 3-chlorophenol by sonolysis were higher than those for 2- and 4-chlorophenol for most experiments conducted, suggesting that the ring structure of 3-chlorophenol provides more sites available for free radical attack. The temporal decomposition behavior of monochlorophenol in aqueous solutions is markedly influenced by the species distribution and the volatility of specific monochlorophenol.