Light-excited photoelectrons coupled with bio-photocatalysis enhanced the degradation efficiency of oxytetracycline |
Ding, R (Ding, Rui); Yan, WF (Yan, Weifu); Wu, Y (Wu, Yan); Xiao, Y (Xiao, Yong); Gang, HY (Gang, Haiyin); Wang, SH (Wang, Shuhua); Chen, LX (Chen, Lixiang); Zhao, F* (Zhao, Feng) |
Intimately coupled photocatalysis and biodegradation (ICPB) is a novel wastewater treatment technique that has potential applications in refractory degradation. This paper reports a synergistic degradation protocol that allowing the transfer of photoelectrons between photocatalysts and microbes without supplementary electron donors or improving the loading rate of the photocatalysts. As a result, a degradation rate of ~94% was sustained for 400 h in a perturbation setup with a hydraulic retention time of 4.0 h. We achieved the degradation of β-apo-oxytetracycline, a stable antimicrobial intermediate compound (half-life of 270 d in soil interstitial water), within 10 min, and no accumulation was observed. Moreover, the required loading rate of the photocatalyst was dramatically reduced to 18.3% compared to previous reports which mentioned much higher rates. The results of our study provided a new strategy to improve the degradation efficiency of oxytetracycline and give new insight into the degradation mechanism of the bio-photocatalytic degradation system. SEM images of the blank sponge carrier (a, b), coated with Bi12O17Cl2 (c, d) and after the synergistic degradation operation for 400 h (e, f). |
Key words:Photoelectrons; Biodegradation; Photocatalytic degradation; Synergistic degradation; Oxytetracycline |
Volume:143 Page:589-598 Journal:WATER RESEARCH |
https://doi.org/10.1016/j.watres.2018.06.068
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