Abstract In this study, for the first time, citric acid was employed as a chelating agent in CuFeS2 synthesis in order to accelerate the regeneration of Fe2+ during the photo–Fenton reaction, promoting a faster production of OH radicals. The novel CuFeS2 material showed remarkable catalytic efficiency for bisphenol A (BPA) degradation during the photo–Fenton process under visible light and near–natural pH, with a rate 10 times faster than that of CuFeS2 prepared without citrate. Furthermore, CuFeS2 promoted rapid generation of OH radicals and showed efficient H2O2 consumption, sustaining the catalytic efficiency and stability even after 4 consecutive cycles of use. CuFeS2 was also efficient for BPA degradation from a municipal wastewater treatment plant effluent. BPA by–products were identified and a mechanism for BPA degradation was proposed. After the photo–Fenton process, no Fe3+ species were identified on the catalyst surface by X–ray photoelectron spectroscopy (XPS), indicating that citric acid accelerated the conversion of Fe3+/Fe2+, thus increasing the generation of OH and the process efficiency.

中文翻译：

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柠檬酸盐改性CuFeS2催化剂的合成对可见光和近中性pH下双酚A的光芬顿降解效率有显着影响

摘要 本研究首次在CuFeS2合成中使用柠檬酸作为螯合剂，以加速光-芬顿反应过程中Fe2+的再生，促进OH自由基的更快产生。新型 CuFeS2 材料在可见光和接近自然 pH 条件下对光-芬顿过程中的双酚 A (BPA) 降解表现出显着的催化效率，其速率比不使用柠檬酸盐制备的 CuFeS2 快 10 倍。此外，CuFeS2 促进了 OH 自由基的快速生成，并表现出高效的 H2O2 消耗，即使在连续使用 4 次循环后仍能保持催化效率和稳定性。CuFeS2 还可以有效地降解市政污水处理厂出水中的 BPA。确定了 BPA 副产品，并提出了 BPA 降解的机制。