Advanced oxidation processes (AOPs) using persulfate system can effectively remove organic pollutants. However, dissolved organic matter (DOM) has multiple effects on AOPs efficiency, and the influence of DOMs from natural sources on AOPs is still unclear. In this study, we explored the effects of soil DOM (SDOM) and fertilizer DOM (FDOM) on tetracycline (TC) removal by persulfate systems. DOMs introduction decreased light transmittance, slightly increased the pH of the systems, and destroyed original adsorption–desorption equilibrium. SDOM promoted most reactive species generation in the initial stage, thus improving the initial TC degradation rate. However, introduction of SDOM and FDOM increased the final TC residual rate. FDOM produced more obvious inhibitory effects on TC degradation. The final TC residual rates in systems containing 7.5 and 15 mg L-1 FDOM (F7.5-TC-PS and F15-TC-PS, respectively) were 25.85 % and 25.52 %, respectively. The inhibitory effects of FDOM on TC degradation were related to the combination between TC and FDOM, with humic acid-like component in FDOM being the main contributor. Besides, the main components in DOMs underwent transformation in the persulfate systems. This study sought to provide insights into the regulatory effects of DOM on TC photo-assisted conversion by AOPs.

中文翻译：

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四环素在受调节的过硫酸盐系统中的光辅助转化：天然溶解有机物的多重作用


使用过硫酸盐系统的高级氧化过程 （AOP） 可以有效去除有机污染物。然而，溶解有机物 （DOM） 对 AOPs 效率有多种影响，天然来源的 DOMs 对 AOPs 的影响尚不清楚。在本研究中，我们探讨了土壤 DOM （SDOM） 和肥料 DOM （FDOM） 对过硫酸盐系统去除四环素 （TC） 的影响。DOMs 的引入降低了透光率，略微增加了系统的 pH 值，并破坏了原始的吸附-解吸平衡。SDOM 在初始阶段促进了大多数反应性物质的产生，从而提高了初始 TC 降解速率。然而，SDOM 和 FDOM 的引入增加了最终的 TC 残留率。FDOM 对 TC 降解产生更明显的抑制作用。在含有 7.5 和 15 mg L-1 FDOM （分别为 F7.5-TC-PS 和 F15-TC-PS） 的系统中，最终 TC 残留率分别为 25.85 % 和 25.52 %。FDOM 对 TC 降解的抑制作用与 TC 和 FDOM 的组合有关，其中 FDOM 中腐殖酸样成分是主要贡献者。此外，DOMs 中的主要成分在过硫酸盐系统中发生了转化。本研究旨在深入了解 DOM 对 AOPs 光辅助转化 TC 的调节作用。