School of Civil Engineering, Wuhan University, Wuhan, 430072, China; Engineering Research Center of Urban Disasters Prevention and Fire Rescue Technology of Hubei Province, Wuhan University, Wuhan, 430072, China.
School of Civil Engineering, Wuhan University, Wuhan, 430072, China; State Key Lab Urban Water Resource & Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China.
Chemosphere. 2019 Oct;233:431-439. doi: 10.1016/j.chemosphere.2019.05.288. Epub 2019 Jun 3.
The transformation of roxarsone (ROX) during UV disinfection with Fe(III) has been investigated. Fe(OH), as the main Fe(III) species at pH = 3, produces HO under UV irradiation leading to the oxidation of ROX. Dissolved oxygen plays a very important role in the continuous conversion of generated Fe to Fe, which ensures a Fe(III)-Fe(II) cycle in the system. The presence of Cl/HCO/NO has little influence on the ROX transformation, whereas PO achieves an obvious inhibitory effect. The transformation of ROX leads to the formation of inorganic arsenic consisting of a much higher amount of As(V) than As(III). LC-MS analysis shows that phenol, o-nitrophenol and arsenic acid were the main transformation products. Both the radical scavenger experiment and electron spin resonance data confirm that the HO is responsible for ROX transformation. The toxic transformation products are found to have potential environmental risks for the natural environment, organisms and human beings.
研究了铁（III）存在下 UV 消毒过程中罗硝唑（ROX）的转化。在 pH=3 时，Fe(OH)作为主要的 Fe(III)物种，在 UV 照射下产生 HO，导致 ROX 的氧化。溶解氧在生成的 Fe 不断转化为 Fe 中起着非常重要的作用，这确保了系统中 Fe(III)-Fe(II)循环。Cl/HCO/NO 的存在对 ROX 的转化几乎没有影响，而 PO 则表现出明显的抑制作用。ROX 的转化导致无机砷的形成，其中 As(V)的含量明显高于 As(III)。LC-MS 分析表明，苯酚、邻硝基苯酚和砷酸是主要的转化产物。自由基清除实验和电子顺磁共振数据均证实 HO 是 ROX 转化的原因。发现有毒的转化产物对自然环境、生物和人类具有潜在的环境风险。
