Abstract: The degradation of 2,4-dichlorophoxyacetic acid (2,4-D)by using ozonation alone（O₃） or ozonation combined with sonication(O₃/US)was studied.The results showed significant synergistic effect of ozone and ultrasound.•OH radical played an important role in the degradation of 2,4-D by the O₃/US technique.Under ultrasound irradiation,mechanical effects of ultrasonic energy enhanced the mass transfer of gaseous ozone to the liquid phase.The enhancement of ultrasound was mainly attributed to that ozone decomposition could be accelerated to produce abundant radicals by cavitation effect, which resulted in high temperatures and pressures during cavitation bubbles collapse.

摘要： 利用臭氧和超声波联合降解苯氧羧酸类除草剂2，4-D，探讨超声波对臭氧氧化的协同作用.实验结果表明，臭氧和超声波协同效应较为明显，反应主要是发生在2，4-D和自由基之间，虽然超声波的机械振荡能强化臭氧传质效果，但超声波强化臭氧降解的能力主要表现在超声波空化效应产生的高能条件促使臭氧迅速分解，产生大量的自由基.