[Efficient oxidative degradation of tetrabromobisphenol A by silver bismuth oxide]

Silver bismuth oxide(BSO) was prepared by a simple ion exchange-coprecipitation method with AgNO3 and NaBiO, .2H2O as raw materials, and then used to oxidatively degrade tetrabromobisphenol A(TBBPA). Effects of the molar ratio of Ag/Bi during BSO preparation and the BSO dosage on the degradation of TBBPA were investigated. The results showed that under the optimized conditions (i.e., the Ag/Bi molar ratio of 1:1, BSO dosage of 1 g x L(-1), 40 mg x L(-1) of TBBPA was completely degraded and the removal of total organic carbon achieved more than 80% within 7 min. The degradation intermediates of TBBPA were identified by ion chromatography, gas chromatograph-mass spectrometer and X-ray photoelectron spectroscopy. The degradation pathway of TBBPA included the debromination, the cleavage of tert-butyl group and the open epoxidation of benzene ring. Based on a quenching study of NaN3, singlet oxygen was proved to play a dominant role in the TBBPA degradation.