College of Civil Engineering, Zhejiang University of Technology, Hangzhou 310014, China; Water Resources and Environmental Institute, Xiamen University of Technology, Xiamen 361005, China.
College of Civil Engineering, Zhejiang University of Technology, Hangzhou 310014, China.
Sci Total Environ. 2020 Jun 25;723:137993. doi: 10.1016/j.scitotenv.2020.137993. Epub 2020 Mar 17.
Ultraviolet light emitting diode (UV-LED)-based advanced oxidation processes (AOPs) including UV-LED/chloramine (UV-LED/NHCl), UV-LED/hydrogen peroxide (UV-LED/HO) and UV-LED/persulfate (UV-LED/PS), were adopted for acetaminophen (AAP) removal. Results showed that AAP could be effectively degraded by the hybrid processes compared to solely using with UV irradiation and oxidants. The AAP degradation in the three UV-LED-based AOPs were in the order of UV-LED/PS > UV-LED/HO > UV-LED/NHCl and followed a pseudo-first-order kinetics. The degradation rate constant (k) increased with increasing oxidant dosage, whereas overdosing lowered the AAP degradation. The second-order rate constants of HO, SO, and Cl with AAP were calculated as 5.15 × 10, 7.66 × 10 and 1.08 × 10 M s, respectively. Under neutral conditions, the contributions of UV-LED, HO, and Cl to AAP degradation were 4.21%, 60.15% and 35.64% in the UV-LED/NHCl system, whereas the respective contributions of UV-LED, HO and SO to AAP degradation were 2.09%, 22.84% and 75.07% in UV-LED/PS system, respectively. Meanwhile, the corresponding contributions of the involved reactive species were found to be pH-dependence. The natural organic materials (NOM) inhibited the AAP degradation, and the presence of Cl, HCO, and NO had different effects on AAP degradation in the three hybrid processes. The AAP degradation was significantly inhibited in the three UV-LED-based AOPs in real water. In addition, the intermediate products were also identified, and possible degradation pathways were proposed in the three UV-LED-based AOPs. The acute toxicity bioassay using bacterium Vibrio fischeri suggested that the UV-LED/PS process was more effective than the UV-LED/HO and UV-LED/NHCl processes in reducing the acute toxicity of the reacted AAP solution. Among the three UV-LED-based AOPs, the UV-LED/PS was found to be the most efficient process for AAP degradation.
基于紫外线发光二极管 (UV-LED) 的高级氧化工艺 (AOPs)，包括 UV-LED/氯胺 (UV-LED/NHCl)、UV-LED/过氧化氢 (UV-LED/HO) 和 UV-LED/过硫酸盐 (UV-LED/PS)，已被用于去除扑热息痛 (AAP)。结果表明，与仅使用紫外线辐射和氧化剂相比，这些混合工艺可更有效地去除 AAP。在这三种基于 UV-LED 的 AOP 中，AAP 的降解顺序为 UV-LED/PS > UV-LED/HO > UV-LED/NHCl，遵循准一级动力学。随着氧化剂剂量的增加，降解速率常数 (k) 增加，而过量的氧化剂会降低 AAP 的降解率。HO、SO 和 Cl 与 AAP 的二级反应速率常数分别为 5.15×10、7.66×10 和 1.08×10 M s。在中性条件下，UV-LED/NHCl 体系中 UV-LED、HO 和 Cl 对 AAP 降解的贡献分别为 4.21%、60.15%和 35.64%，而在 UV-LED/PS 体系中，UV-LED、HO 和 SO 对 AAP 降解的贡献分别为 2.09%、22.84%和 75.07%。同时，发现涉及的活性物质的贡献随 pH 值而变化。天然有机物质 (NOM) 抑制了 AAP 的降解，而 Cl、HCO 和 NO 的存在对三种混合工艺中的 AAP 降解有不同的影响。在三种基于 UV-LED 的 AOP 中，实际水样中的 AAP 降解受到显著抑制。此外，还鉴定了中间产物，并提出了三种基于 UV-LED 的 AOP 中的可能降解途径。利用细菌发光杆菌进行的急性毒性生物测定表明，与 UV-LED/HO 和 UV-LED/NHCl 工艺相比，UV-LED/PS 工艺在降低反应 AAP 溶液的急性毒性方面更有效。在这三种基于 UV-LED 的 AOP 中，UV-LED/PS 被发现是去除 AAP 的最有效工艺。
