基于黄铁矿的类Fenton工艺已被广泛研究用于废水净化;然而,大多数相关研究过分强调由Fe2水溶液介导的均相Fenton反应,导致所提出的技术面临的问题,例如pH调节和过量的铁污泥生产的额外酸要求。在这里,通过原位壳隔离纳米粒子增强拉曼光谱(SHINERS),定制双室反应器实验,和一系列对照实验,在黄铁矿/H2O2过程中发现了显著的羟基自由基生成,虽然主要的反应性铁物种被证实在黄铁矿表面的结构Fe位点,而不是在次生铁矿物和表面吸附Fe2+的结构Fe(II)。因此,即使同质Fenton途径受到显著抑制,在pH为4时,黄铁矿/H2O2工艺对磺胺甲恶唑(SMX)具有显着的降解效率。此外,发现黄铁矿/H2O2工艺可选择性去除50μM对黄铁矿具有高亲和力的污染物(双酚A,卡马西平,硝基苯,和SMX),即使在50-100mM甲醇的存在下。与典型的铁基还原催化剂(零价铁,ZVI),黄铁矿介导的Fenton工艺在pH4下具有更大的实际应用潜力,使铁污泥产量减少了43.75倍,并使H2O2的利用效率几乎翻了一番。此外,与ZVI相比,氧化过程中在黄铁矿表面形成的氧化铁最少。因此,经过七个周期的降解实验,黄铁矿/H2O2工艺的去污效率保持稳定。这些发现对于了解黄铁矿在自然和工程过程中的复杂环境行为至关重要,也为黄铁矿资源的有效利用提供了新的视角。
Pyrite-based Fenton-like processes have been extensively studied for wastewater decontamination; however, most relevant studies placed excessive emphasis on the homogeneous Fenton reaction mediated by aqueous Fe2+, resulting in the proposed technologies facing issues such as additional acid requirements for pH adjustment and excessive iron sludge production. Herein, through in situ shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS), custom dual-chamber reactor experiments, and a series of control experiments, significant hydroxyl radical generation was identified during the
pyrite/H2O2 process, while the dominant reactive iron species was verified to the structural Fe sites on the pyrite surface, rather than structural Fe(II) in secondary iron minerals and surface adsorbed Fe2+. Consequently, even with significant suppression of the homogeneous Fenton pathway, the pyrite/H2O2 process exhibited significant degradation efficiency for sulfamethoxazole (SMX) at pH 4. Moreover, the pyrite/H2O2 process was found to selectively remove 50 μM of pollutants with high affinity for pyrite (bisphenol A, carbamazepine, nitrobenzene, and SMX), even in the presence of 50-100 mM methanol. Compared to the typical iron-based reductive catalyst (zero-valent iron, ZVI),
pyrite mediated a Fenton process with greater potential for practical applications at pH 4, achieving a 43.75-fold reduction in iron sludge production and almost doubling the H2O2 utilization efficiency. Additionally, in contrast to ZVI, minimal iron oxide formed on the
pyrite surface during the oxidation process. Thus, after seven cycles of degradation experiments, the decontamination efficiency of the
pyrite/H2O2 process remained stable. These findings are crucial for understanding the complex environmental behavior of pyrite in both natural and engineering processes and provide a new perspective for the efficient utilization of pyrite resources as well.