Abstract:
Treatment of industrial thallium(Tl)-containing wastewater is crucial for mitigating environmental risks and health threats associated with this toxic metal. The incorporation of Mn oxides (MnOx) into the filtration system is a promising solution for efficient Tl(I) removal. However, further research is needed to elucidate the underlying mechanism behind MnOx-enhanced filtration and the rules of its stable operation. In this study, limestone, a cost-effective material, was selected as the filter media. Raw water with Mn(II), Tl(I), and other pollutants was prepared after a thorough investigation of actual industrial wastewater conditions. KMnO4 was added to induce the formation of MnO2 on limestone surfaces, while long-term operation led to enrichment of manganese oxidizing microorganisms (MnOM). Results revealed a dual mechanism. Firstly, most Mn(II) were oxidized by KMnO4 to form MnO2 attaching to limestone sands, and both Tl(I) and residual Mn(II) were adsorbed onto the newly formed MnO2. Subsequently, enzymes secreted by MnOM facilitated oxidation of remaining Mn(II), resulting in the generation of biogenic manganese oxides (BioMnOx) with numerous vacancies during long-term operation. The generated BioMnOx not only adsorbed Mn(II) and Tl(I) but also promoted their oxidation process. This approach offers an effective and sustainable method for removing both Mn(II) and Tl(I) from industrial wastewater, thereby addressing the challenges posed by thallium-contaminated effluents.
摘要:
工业含铊(Tl)废水的处理对于减轻与这种有毒金属相关的环境风险和健康威胁至关重要。将Mn氧化物(MnOx)掺入过滤系统是有效去除Tl(I)的有希望的解决方案。然而,需要进一步的研究来阐明MnOx增强过滤背后的潜在机制及其稳定运行的规则。在这项研究中,石灰石,一种具有成本效益的材料,被选为过滤介质。含Mn(II)的原水,Tl(I),和其他污染物是在对实际工业废水状况进行彻底调查后制备的。添加KMnO4以诱导石灰石表面上MnO2的形成,而长期运行导致锰氧化微生物(MnOM)的富集。结果揭示了双重机制。首先,大多数Mn(II)被KMnO4氧化形成MnO2附着在石灰石砂上,Tl(I)和残余Mn(II)都吸附在新形成的MnO2上。随后,MnOM分泌的酶促进了剩余Mn(II)的氧化,导致在长期操作期间产生具有许多空位的生物锰氧化物(BioMnOx)。生成的BioMnOx不仅吸附了Mn(II)和Tl(I),而且促进了它们的氧化过程。这种方法提供了一种有效且可持续的方法,用于从工业废水中去除Mn(II)和Tl(I)。从而解决铊污染废水带来的挑战。