The typical antibiotic Oxytetracycline (OTC) remained in the environment and it was widely used. And the migration and transformation of OTC in natural environment and its harmfulness had become the focus of attention. Thus, the influence of Fe(II/III)‐OTC complex on degradation of OTC by Fe(II)/H₂O₂ under simulated solar light was investigated. The results showed that the average ratio of OTC‐Fe(II/III) complexes formed by OTC and Fe(III) was 1:1 at pH = 2.5. In addition, it was difficult to obtain the stability constant of Fe(III)‐OTC complexes effectively considering the morphology of Fe(III) and the complexation sites of OTC. And when OTC:Fe(II):H₂O₂ = 1:1.5:2, the removal rate of OTC was 82% after 1 h, however, simulated solar light could not improve the degradation of OTC effectively. Furthermore, the existence of OTC‐Fe(II/III) complex led to the slow degradation stage of OTC degradation by Fe(II)/H₂O₂. It could be concluded that the Fe(III)‐OTC complex might prolong the retention time of OTC in the environment.

中文翻译：

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Fe（III）-OTC配合物对模拟太阳光下Fe（II）/ H2O2降解OTC的影响

典型的抗生素土霉素（OTC）保留在环境中，并被广泛使用。而OTC在自然环境中的迁移转化及其危害已成为人们关注的焦点。因此，研究了Fe（II / III）-OTC配合物对Fe（II）/ H ₂ O ₂在模拟太阳光下降解OTC的影响。结果表明，在pH = 2.5时，由OTC和Fe（III）形成的OTC-Fe（II / III）复合物的平均比例为1：1。此外，考虑到Fe（III）的形态和OTC的络合部位，很难有效地获得Fe（III）-OTC络合物的稳定常数。当OTC：Fe（II）：H ₂ O ₂ = 1：1.5：2，OTC的去除率在1 h后为82％，但是模拟太阳光不能有效地改善OTC的降解。此外，OTC-Fe（II / III）配合物的存在导致Fe（II）/ H ₂ O ₂导致OTC降解的缓慢降解阶段。可以得出结论，Fe（III）-OTC复合物可能会延长OTC在环境中的保留时间。