Kinetics and Influence Factors of Ultrasonic Degradation of Bisphenol A in Water

Abstract:

The effect and kinetics of degradation of bisphenol A (BPA) by ultrasonic at the frequency of 800 kHz were studied.The effects of some additives,such as t-butyl alcohol,H2O2,humic acid and air bubbles,were investigated as external factors.The results show that the ultrasonic degradation of BPA follows a pseudofirst order kinetic model and the rate constant decreases with the increasing initial concentration.It is identified that hydroxyl radical is a major participant in the ultrasonic degradation of BPA by t-butyl alcohol.The rate constant increases by 32% at low H2O2 concentration of 0.1 mmol?L-1.However,the degradation of BPA is hindered with the further addition of H2O2.The boundary point of the molar rate is about 200:1 between H2O2 and BPA.Moreover,humic acid in aqueous solution hinders the degradation of BPA and the rate constant decreases with the increasing humic acid dose.The common bubbles added can prevent BPA from closing to the interface of cavitation bubble and reacting with ?OH,which is adverse to the degradation of BPA.

Key words:ultrasonic; bisphenol A; radical oxidation; H2O2; humic acid