Degradation of Tetrabromobisphenol A by Sulfidated Nanoscale Zerovalent Iron in a Dynamic Two-Step Anoxic/Oxic Process.
Degradation of Tetrabromobisphenol A by Sulfidated Nanoscale Zerovalent Iron in a Dynamic Two-Step Anoxic/Oxic Process.
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DOI：
10.1021/acs.est.8b06834
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发表时间：
2019-05
影响因子：
11.4
通讯作者：
Jun Wu;Jian Zhao;J. Hou;R. Zeng;B. Xing
中科院分区：
文献类型：
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作者：
Jun Wu;Jian Zhao;J. Hou;R. Zeng;B. Xing
采用硫化纳米级零价铁 (S-nZVI) 的动态两步缺氧/好氧工艺来降解四溴双酚 A (TBBPA)。在缺氧阶段，TBBPA遵循四步顺序脱溴途径，完全转化为双酚A（BPA），最佳S/Fe摩尔比为0.3。 S-nZVI 抑制 H2 析出并保留 Fe(0) 的还原能力。 Fe(0)，而不是 S-nZVI 中形成的 FeS，负责 TBBPA 脱溴。在好氧阶段，产物BPA受到·OH的攻击，转化为二羟基苯和苯醌，最终通过开环反应实现矿化。硫化过程通过表面结合的 Fe(II) 通过双电子转移途径促进·OH 的产生，其中 FeS 中的结构 Fe(II) 以及 Fe(III) 被 Fe(0) 还原而再生的 Fe(II) 对 BPA 的总降解发挥着重要作用。经氧化处理后，S-nZVI 转化为 S8 和 α-FeOOH。经过这两个步骤，实现了TBBPA的完全降解。这项研究证明了难降解污染物在动态两步缺氧/好氧过程中完全降解的可行性，从而拓宽了 S-nZVI 在水处理环境应用中的效用。
A dynamic two-step anoxic/oxic process using sulfidated nanoscale zerovalent iron (S-nZVI) was employed to degrade tetrabromobisphenol A (TBBPA). In the anoxic stage, TBBPA followed a four-step sequential debromination pathway and was completely transformed to bisphenol A (BPA) with the optimal S/Fe molar ratio of 0.3. S-nZVI inhibited H2 evolution and preserved the reducing capacity of Fe(0). Fe(0), rather than the formed FeS in S-nZVI, was responsible for TBBPA debromination. In the oxic stage, the product BPA was attacked by •OH, transformed to dihydroxybenzenes and benzoquinones, and eventually, achieved mineralization via ring-opening reactions. The sulfidation process facilitated •OH production through a two-electron transfer pathway by surface-bound Fe(II), in which structural Fe(II) in FeS and regenerated Fe(II) from Fe(III) reduction by Fe(0) played significant roles toward total BPA degradation. S-nZVI was transformed to S8 and α-FeOOH after the oxic treatment. After these two steps, complete degradation of TBBPA was achieved. This study demonstrated the feasibility that refractory contaminants could be completely degraded in the dynamic two-step anoxic/oxic process, thus broadening the utility of S-nZVI for environmental applications in water treatment.