Electrochemical bacteria Shewanella oneidensis MR-4 (MR-4) was used to biologically generate cadmium sulfide (bio-CdS) nanocrystals and construct a self-assembled intimately coupled photocatalysis-biodegradation system (SA-ICPB) to remove cadmium (Cd) and tetracycline hydrochloride (TCH) from wastewater. The characterization using EDS, TEM, XRD, XPS, and UV-vis confirmed the successful CdS bio-synthesis and its visible-light response capacity (520 nm). 98.4% of Cd2+ (2 mM) was removed during bio-CdS generation within 30 min. The elec-trochemical analysis confirmed the photoelectric response capability of the bio-CdS as well as its photocatalytic efficiency. Under visible light, SA-ICPB entirely eliminated TCH (30 mg/L). In 2 h, 87.2% and 43.0% of TCH were removed separately with and without oxygen. 55.7% more chemical oxygen demand (COD) was removed with oxygen participation, indicating the degradation intermediates elimination by SA-ICPB required oxygen participation. Biodegradation dominated the process under aerobic circumstances. Electron paramagnetic resonance analysis indicated that h+ and .O2- played a decisive role in photocatalytic degradation. Mass spec-trometry analysis proved that TCH was dehydrated, dealkylated, and ring-opened before mineralizing. In conclusion, MR-4 can spontaneously generate SA-ICPB and rapidly-deeply eliminate antibiotics by coupling photocatalytic and microbial degradation. Such an approach was efficient for the deep degradation of persistent organic pollutants with antimicrobial properties.
Publication name |
Journal Of Hazardous Materials, Volume 449, Article Number 131018, DOI 10.1016/j.jhazmat.2023.131018, Published MAY 5 2023 |
Author(s) |
Wang, Yu; Qiu, Hang; Niu, Huan; Liu, Hao; Liu, Jinchang; Jia, Yinxue; Ma, Haitao; Xu, Fei; Hao, Likai; Qiu, Zhongping; Wang, Can |
Corresponding author(s) |
Qiu, Zhongping; Wang, Can zhpqiu@swjtu.edu.cn; wangcan@swjtu.edu.cn Southwest Jiaotong Univ, Sichuan Engn Res Ctr Biomimet Synth Nat Drugs, Sch Life Sci & Engn, Chengdu 610031, Sichuan, Peoples R China |
Author(s) from IGCAS |
Hao, Likai | View here for the details
|
|
|