Sciscenko Iván, Arques Antonio, Escudero-Oñate Carlos, Roccamante Melina, Ruiz-Delgado Ana, Miralles-Cuevas Sara, Malato Sixto, Oller Isabel
Departamento de Ingeniería Textil y Papelera, Universitat Politècnica de València (UPV), Plaza Ferrándiz y Carbonell s/n, 03801 Alcoy, Spain.
Institute for Energy Technology (IFE), Instituttveien 18, Kjeller, 2007 Lillestrom, Norway.
Nanomaterials (Basel). 2021 Nov 3;11(11):2948. doi: 10.3390/nano11112948.
The development of treatment trains for pollutant degradation employing zerovalent iron has been attracting a lot of interest in the last few years. This approach consists of pre-treatment only with zerovalent iron, followed by a Fenton oxidation taking advantage of the iron ions released in the first step. In this work, the advantages/disadvantages of this strategy were studied employing commercial zerovalent iron microparticles (mZVI). The effect of the initial amount of mZVI, HO, pH, conductivity, anions and dissolved oxygen were analysed using -nitrobenzoic acid (PNBA) as model pollutant. 83% reduction of PNBA 6 µM into -aminobenzoic acid (PABA) was achieved in natural water at an initial pH 3.0 and 1.4 g/L of mZVI, under aerobic conditions, in 2 h. An evaluation of the convenience of removing mZVI after the reductive phase before the Fenton oxidation was investigated together with mZVI reusability. The Fenton step against the more reactive PABA required 50 mg/L of HO to achieve more than 96% removal in 15 min at pH 7.5 (final pH from the reductive step). At least one complete reuse cycle (reduction/oxidation) was achieved with the separated mZVI. This approach might be interesting to treat wastewater containing pollutants initially resistant to hydroxyl radicals.
在过去几年中，采用零价铁进行污染物降解的处理流程开发引起了广泛关注。这种方法仅包括先用零价铁进行预处理，然后利用第一步中释放的铁离子进行芬顿氧化。在这项工作中，使用商业零价铁微粒（mZVI）研究了该策略的优缺点。以对硝基苯甲酸（PNBA）作为模型污染物，分析了mZVI初始用量、过氧化氢、pH值、电导率、阴离子和溶解氧的影响。在初始pH值为3.0、mZVI用量为1.4 g/L的天然水中，在有氧条件下，2小时内实现了将6 μM的PNBA降解83%生成对氨基苯甲酸（PABA）。研究了在芬顿氧化之前的还原阶段之后去除mZVI的便利性以及mZVI的可重复使用性。对于更具反应性的PABA，芬顿步骤在pH值为7.5（还原步骤后的最终pH值）时需要50 mg/L的过氧化氢，才能在15分钟内实现超过96%的去除率。分离出的mZVI至少实现了一个完整的重复使用循环（还原/氧化）。这种方法对于处理最初对羟基自由基具有抗性的污染物的废水可能很有意义。
