Fe-mediated autotrophic denitrification has emerged as a promising technology for low carbon-to-nitrogen (C/N) wastewater treatment due to its cost-effectiveness, operational safety, and independence from organic carbon. While several reviews have addressed this process, there is still a lack of comprehensive analyses that connect iron materials, denitrification performance, and microbial communities. The practical applicability of solid-phase iron has received little attention, and the key controversial issue - Fe(Ⅱ) oxidation pathway - has not been specifically examined. This review systematically examines both liquid- and solid-phase iron sources, with particular emphasis on the practical applicability of solid-phase iron, and further provides an integrated discussion of denitrification performance and associated functional microbes. In addition, this review summarizes a range of iron-oxidizing denitrifiers and highlights several key genera in detail. It also provides an in-depth analysis of Fe(Ⅱ) oxidation pathways, with particular attention to the ongoing debate regarding the involvement of enzymatic mechanisms. Moreover, the latest advancements in both natural and engineered applications are reviewed. Operational parameters such as temperature (T), pH, dissolved oxygen (DO), Fe/N ratio, and other influencing factors are discussed. Finally, several critical challenges that fundamentally affect Fe-mediated autotrophic denitrification are highlighted. This review aims to support the practical implementation of Fe-mediated autotrophic denitrification in low C/N wastewater treatment and contribute to the sustainable development of environmentally friendly biotechnologies for advanced nitrogen control.

中文翻译：

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Fe（0）/Fe（II.） 介导的低 C/N 废水处理自养反硝化研究进展

Fe 介导的自养反硝化已成为一种很有前途的低碳制氮 （C/N） 废水处理技术，因为它具有成本效益、作安全性和不受有机碳的影响。虽然有几篇综述已经解决了这一过程，但仍然缺乏将铁材料、反硝化性能和微生物群落联系起来的全面分析。固相铁的实际适用性很少受到关注，关键的争议问题 - Fe（II.） 氧化途径 - 尚未得到具体研究。本综述系统地研究了液相和固相铁源，特别强调了固相铁的实际适用性，并进一步提供了对反硝化性能和相关功能微生物的综合讨论。此外，本文还总结了一系列铁氧化反式剂，并详细强调了几个关键属。它还对 Fe（II.） 氧化途径进行了深入分析，特别关注了正在进行的关于酶促机制参与的争论。此外，还回顾了自然和工程应用的最新进展。讨论了温度 （T）、pH、溶解氧 （DO）、Fe/N 比率和其他影响因素等作参数。最后，强调了从根本上影响 Fe 介导的自养反式反硝化的几个关键挑战。本文旨在支持铁介导的自养反硝化作用在低 C/N 废水处理中的实际实施，并为用于高级氮控制的环境友好型生物技术的可持续发展做出贡献。