The accessibility of clean water and green environment are the major requirements for survival and sustainable development. In this study, iron-coated sand, derived from acid mine drainage effluent, has been applied as a heterogeneous catalyst. Treatment with H 2 O 2 , iron-coated sand, and iron-coated sand-Fenton processes is compared for the COD removals from municipal wastewater effluent. The results showed that the iron-coated sand catalyzed Fenton process could generate hydroxyl radicals (•OH) and oxidize the organic pollutants. Fenton process based on the iron-coated sand catalyst proved to be the most efficient process. The effect of operating conditions such as initial pH and Fenton’s reagent doses, i.e. initial H 2 O 2 and iron on the organics oxidation from such wastewater was investigated. The results showed that 70% removal efficiency of COD was obtained within 30 min under optimized conditions (pH 3.0, H 2 O 2 400 mg/L and iron 40 mg/L). The rate equation of iron-coated sand-Fenton system was simply expressed by the second-order equation and the model was found to fit well the data. Thermodynamic analysis of the results indicated that the iron-coated sand-Fenton oxidation is non-spontaneous and endothermic in nature. Regeneration of iron-coated sand was attempted and the catalyst had a good stability and reusability for successive treatments and reducing the quantity of sludge produced in Fenton reactions. Thus, expanding the sustainability scope of iron-coated sand based Fenton catalyst and offer new sustainable and inexpensive alternatives for the classical Fenton process. Iron recovered from acid mine drainage to prepare iron coated-sand as a Fenton source. Novel Fenton reaction is proposed for treating polymer industry wastewater. The system avoids iron sludge by-product by providing catalyst reusability. The approach points the competitive novel iron waste source to applied as a Fenton technology.

中文翻译：

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酸性矿山废水含铁砂作为催化氧化剂修复城市污水

清洁水源和绿色环境的可及性是生存和可持续发展的主要要求。在这项研究中，来自酸性矿山排水流出物的铁包覆砂已被用作非均相催化剂。比较了用 H 2 O 2 、铁包覆砂和铁包覆砂-芬顿工艺处理市政废水的 COD 去除率。结果表明，铁包覆砂催化的Fenton过程可以产生羟基自由基(•OH)并氧化有机污染物。基于铁包覆砂催化剂的芬顿工艺被证明是最有效的工艺。研究了操作条件（例如初始 pH 值和芬顿试剂剂量，即初始 H 2 O 2 和铁）对来自此类废水的有机物氧化的影响。结果表明，在优化条件下（pH 3.0、H 2 O 2 400 mg/L、铁40 mg/L），30 min内COD去除率达到70%。铁包覆砂-Fenton体系的速率方程用二阶方程简单表示，发现模型与数据拟合良好。结果的热力学分析表明，铁包覆砂-芬顿氧化本质上是非自发的和吸热的。尝试再生铁包覆砂，催化剂具有良好的稳定性和可重复使用性，可用于后续处理并减少芬顿反应中产生的污泥量。因此，扩大了铁包覆砂基芬顿催化剂的可持续性范围，并为经典芬顿工艺提供了新的可持续且廉价的替代品。从酸性矿山排水中回收铁以制备铁包覆砂作为芬顿源。提出了新的芬顿反应来处理聚合物工业废水。该系统通过提供催化剂可重复使用性来避免铁污泥副产品。该方法将具有竞争力的新型铁废料源作为 Fenton 技术加以应用。