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洛克沙砷(ROX)饲料添加剂在农业的普遍使用,导致大量的ROX进入自然水体,引起环境污染.为了修复含ROX废水,首次提出采用接触辉光放电等离子体(CGDP)氧化ROX,并考察了多种因素对ROX降解效果的影响.结果表明,ROX能被CGDP完全氧化降解,且As(Ⅴ)是其最终降解产物;输入能量的增加利于ROX的氧化,而pH值对ROX的降解影响较小;在辉光放电最佳条件(输入能量58 W,pH 4.O)下,加入100 μmol·L-1ROX,42 min内降解率为97％,As(Ⅴ)的生成量可达95 μmol·L-1.此外,加入一定量的Fe(Ⅱ),因其可以通过利用CGDP原位产生的H2O2通过芬顿反应产生大量额外的·OH,而能显著地催化ROX转化为无机砷.通过自由基捕获实验,证明了·OH在ROX降解中起主要作用并探索了其氧化降解机理.“,”Organoarsenic compounds,such as roxarsone (ROX),are extensively used as feed additives in the agricultural industry,and have become a serious environmental concern.This study investigated unprecedentedly the applicability of the contact glow discharge process (CGDP) for ROX oxidation and degradation in aqueous solution,and evaluated the effects of various reaction conditions on ROX conversion.The results indicated that ROX could be completely degraded,with As(Ⅴ) as the final product.The higher energy input was beneficial for a higher As(Ⅴ) production efficiency,whereas the solution pH did not seem to influence the ROX oxidation efficiency.Consequently,approximately 97％ of ROX degraded,and more than 95 μmol · L-1 As(Ⅴ) were generated within 42 min under the optimum glow discharge condition (58 W of input energy,pH 4.0).Furthermore,addition of Fe(Ⅱ) into the CGDP system significantly enhanced the ROX oxidation,due to the consumption of in-situ electrogenerated H2O2 in CGDP and the generation of additional-OH.Furthermore,the experiments of quenching active radicals indicated that · OH plays an important role in the mineralization of ROX to arsenate,and also confirmed the ROX degradation mechanism in the CGDP system.