State Key Laboratory of Advanced Metallurgy, School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing, 100083, PR China.
Institute of Resources and Environmental Engineering, Shanxi University, Taiyuan, 030006, China.
J Environ Manage. 2022 Jan 15;302(Pt B):114119. doi: 10.1016/j.jenvman.2021.114119. Epub 2021 Nov 15.
Metal-doped MgFeO spinel ferrite synthesized from saprolite laterite nickel ore was verified as an efficient heterogeneous Fenton-like catalyst for degrading antibiotics including tetracycline (TC) and metronidazole (MNZ) in a "catalyst/oxalic acid (HCO)/visible light (vis)" system. The degradation efficiencies reached over 95% and total organic carbon (TOC) removal efficiencies were nearly 50% of the two antibiotics within 210 min, under the optimal conditions, especially 90% catalytic activity of the fresh catalyst was maintained after five cycles, suggesting the ferrite possessed excellent degrading performance, cycling stability and applicability. Moreover, the degradation mechanism and pathway of TC were elucidated in detail. Results revealed that the [≡Fe(CO)] complex ions formed by octahedral Fe in spinel ferrite with oxalate ions on the surface of MgFeO, played the key role in production of ·OH radicals which decomposed antibiotic TC into small molecules even mineralized in three pathways. Cost-effective preparation, high catalytic performance and long cycle life may accelerate the practical application of the heterogeneous Fenton-like catalyst.
从腐泥土镍矿合成的金属掺杂 MgFeO 尖晶石铁氧体被验证为一种高效的非均相类 Fenton 催化剂，可在“催化剂/草酸（HCO）/可见光（vis）”体系中降解抗生素，包括四环素（TC）和甲硝唑（MNZ）。在最佳条件下，两种抗生素在 210 分钟内的降解效率均超过 95%，TOC 去除效率接近 50%，尤其是新鲜催化剂的催化活性保持在 90%，经过五次循环后仍保持稳定，表明该铁氧体具有良好的降解性能、循环稳定性和适用性。此外，还详细阐明了 TC 的降解机制和途径。结果表明，尖晶石铁氧体中八面体 Fe 与表面上的草酸根离子形成的[≡Fe(CO)]配合物离子在产生·OH 自由基方面发挥了关键作用，·OH 自由基将抗生素 TC 分解成小分子，甚至在三条途径中矿化。该非均相类 Fenton 催化剂具有成本效益高、催化性能高和循环寿命长等特点，可能会加速其实际应用。
