Abstract: Factors influencing the ultrasound-Fenton combined process for treating alkaline waste of refinery were investigated including the effects of n(H2O2)/n(Fe2+), H2O2 concentration, initial system pH value and ultrasonic frequency on the removal rates of phenol and COD. Test results showed that at constant reaction temperature of 30 ℃ and ultrasonic frequency of 25 kHz, under the optimum process conditions of a n(H2O2)/n(Fe2+) of 30, H2O2 concentration of 293.7 mmol/L, initial system pH value of 4.0, an ultrasonic power of 900 W and a reaction time of 60 min, the removal rate of phenol and COD by this combined process reached 87.4% and 42.2%, respectively. Treatment by this combined process was much better than that of by single ultrasound method or single Fenton oxidation.

Key words: alkaline waste, Fenton reagent, ultrasound, reaction kinetics