Effective degradation of tetracycline via recyclable cellulose nanofibrils/polyvinyl alcohol/Fe 3 O 4 hybrid hydrogel as a photo-Fenton catalyst.

In this work, the method of in-situ co-precipitation was used to prepare PVA/CNF/Fe ₃ O ₄ hybrid hydrogel, and the relationship between its structure and performance was explored. The Fe ₃ O ₄ NPs prepared by this method were dispersed on the carrier PVA/CNF hydrogel and were easy to recover. The catalytic degradation of tetracycline was investigated using PVA/CNF/Fe ₃ O ₄ hybrid hydrogel as photo-Fenton catalysts. The results showed that light and hydrogel carriers were pivotal factors in promoting Fe ²⁺ and Fe ³⁺ cycling and that the PVA/CNF/Fe ₃ O ₄ hybrid hydrogel as catalysts were able to activate H ₂ O ₂ to generate a large amount of oxygen radical •OH, resulting in efficient removal of tetracycline. The tetracycline degradation followed a proposed first-order kinetic model and achieved a removal rate of about 98% in 120 min at an optimum pH of 3, H ₂ O ₂ 100 mM, catalyst 0.3 g/L, and a temperature of 25 °C.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
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