A novel degradation method for organic pollutants:bubbling cavitation

Investigations into the degradation of dyes such as acid red B were carried out using air bubbling combined with glass balls(bubbling cavitation).In addition,the effects of bubbling time,initial concentration,glass ball diameter,solution acidity and gas flow rate on the degradation of acid red B were studied.The results showed that the degradation ratio of acid red B reached over 97% for a 5.0 h bubbling time,10 mg·L-1 initial concentration,3.0~3.5 mm glass balls,pH = 6.0 and 4.5 L·min-1 gas flow rate at room temperature(25℃).Meanwhile,the mechanism of bubbling cavitation and the degradation mechanism of organic pollutants are discussed.We propose that when two small bubbles collapse into a large one,the inner wall tension between the bubbles reaches a maximum so that the bubbles break.The large amount of energy released in the process induces H2O and O2 to form ·OH and ·O-2 radicals which are strongly oxidizing.Thus,the organic pollutants in the solution are degraded.