Abstract:
Three protocols, UV photolysis alone (Ph), biodegradation alone (B), and intimately coupled photolysis and biodegradation (Ph&B), were respectively used for degradation of sulfamethoxazole (SMX) in batch to test SMX degradation rates and mineralization degree. SMX was more inhibition to biofilm by comparing with the effect of initial SMX concentration on initial SMX degradation rate and average degradation rate, but the inhibition could be relieved by means of UV irradiation, which resulted in accelerated degradation of SMX. The average SMX degradation rate by Ph&B was twice as that by Ph and 4 times as that by B. The nitrogen has significant effect on bioactivity of biofilm degrading SMX, while the released nitrogen from SMX under UV irradiation was assimilated by biofilm partly. In addition, when protocol Ph&B was used for degradation of SMX, the mineralization degree could be increased due to synergy of photolysis and biodegradation, and the degree was 8.4 times as protocol Ph and 2.2 times as protocol B.