Water pollution is calling for a sustainable remediation method such as the use of metallic iron (Fe⁰) to reduce and filter some pollutants, yet the reactivity and hydraulic conductivity of iron filters decline over time under field conditions. Here we review iron filters with focus on metallic corrosion in porous media, flaws in designing iron filters, next-generation filters and perspectives such as safe drinking water supply, iron for anaemia control and coping with a reactive material. We argue that assumptions sustaining the design of current Fe⁰ filters are not valid because proposed solutions address the issues of declining iron reactivity and hydraulic conductivity separately. Alternatively, a recent approach suggest that each individual Fe⁰ atom corroding within a filter contributes to both reactivity and permeability loss. This approach applies well to alternative iron materials such as bimetallics, composites, hybrid aggregates, e.g. Fe⁰/sand, and nano-Fe⁰. Characterizing the intrinsic reactivity of individual Fe⁰ materials is a prerequisite to designing sustainable filters. Indeed, Fe⁰ ratio, Fe⁰ type, Fe⁰ shape, initial porosity, e.g. pore size and pore size distribution, and nature and size of admixing aggregates, e.g. pumice, pyrite and sand, are interrelated parameters which all influence the generation and accumulation of iron corrosion products. Fe⁰ should be characterized in long-term experiments, e.g. 12 months or longer, for Fe dissolution, H₂ generation and removal of contaminants in three media, i.e., tap water, spring water and saline water, to allow reactivity comparison and designing field-scale filters.

水污染需要可持续的修复方法，例如使用金属铁（Fe ⁰）来减少和过滤一些污染物，但铁过滤器的反应性和导水率在现场条件下会随着时间的推移而下降。在这里，我们回顾了铁过滤器，重点关注多孔介质中的金属腐蚀、设计铁过滤器的缺陷、下一代过滤器以及安全饮用水供应、铁用于贫血控制和应对反应材料等观点。我们认为维持当前 Fe ⁰过滤器设计的假设是无效的，因为所提出的解决方案分别解决了铁反应性和水力传导性下降的问题。或者，最近的方法表明，过滤器内的每个单独的 Fe ⁰原子腐蚀都会导致反应性和渗透性损失。该方法很好地适用于替代铁材料，例如双金属、复合材料、混合骨料，例如Fe ⁰ /砂和纳米Fe ⁰。表征各个 Fe ⁰材料的固有反应性是设计可持续过滤器的先决条件。事实上，Fe ⁰比例、Fe ⁰类型、Fe ⁰形状、初始孔隙率（例如孔径和孔径分布）以及混合聚集体（例如浮石、黄铁矿和砂）的性质和尺寸是均影响生成和积累的相互关联的参数。铁腐蚀产物。 Fe ⁰应在长期实验中进行表征，例如12个月或更长时间，用于自来水、泉水和盐水三种介质中Fe的溶解、H _{2 的}产生和污染物的去除，以便进行反应性比较和设计现场- 刻度过滤器。