State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, PR China.
State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
J Hazard Mater. 2022 Aug 15;436:129092. doi: 10.1016/j.jhazmat.2022.129092. Epub 2022 May 10.
This study constructed a FeS-based Fenton-like process to explore the degradation of TTC in the presence of copper ions. The acidic condition of pH 3 was more favorable to the HO decomposition and TTC degradation, and it was slightly enhanced by Cu(II). The production of •OH from HO was revealed through radical scavenging and benzoic acid probe experiments, and the ratio of HO decomposition to •OH production was about 1-1.5, which is comparatively consistent with the theoretical ratio. FeS-based Fenton process was proved to be a homogenous system, the slow release of Fe(II) source and the autocatalytic cycle of Fe(III) to Fe(II) resulting from the reductive species of TTC and dissolved S(-II) improved the production of •OH and the degradation of TTC, which was proved by comparing TTC degradation, TOC removal, HO decomposition and Fe(II) concentration with different iron sources (FeS, Fe(II) and Fe(III)) and external addition of dissolved S(-II). The possible degradation pathways of TTC were subsequently inferred according to the detected products by LC-MS. Understanding these autocatalytic processes is essential to reveal the transformation of redox-active substances in environments and may have potential significance in applying FeS-based Fenton-like process for the treatment of wastewater containing reductive organic matters.
本研究构建了基于 FeS 的类 Fenton 过程，以探索在铜离子存在下 TTC 的降解。pH 值为 3 的酸性条件更有利于 HO 的分解和 TTC 的降解，并且略微被 Cu(II) 增强。通过自由基清除和苯甲酸探针实验揭示了 HO 产生 •OH 的过程，HO 分解和 •OH 产生的比例约为 1-1.5，与理论比例相当一致。基于 FeS 的 Fenton 过程被证明是均相体系，TTC 和溶解的 S(-II) 的还原物种导致 Fe(II) 源的缓慢释放和 Fe(III) 到 Fe(II)的自催化循环，提高了 •OH 的产生和 TTC 的降解，这通过比较不同铁源（FeS、Fe(II) 和 Fe(III)）和溶解的 S(-II)的外加对 TTC 降解、TOC 去除、HO 分解和 Fe(II)浓度的影响得到了证明。根据 LC-MS 检测到的产物，随后推断了 TTC 的可能降解途径。了解这些自催化过程对于揭示环境中氧化还原活性物质的转化至关重要，并且在应用基于 FeS 的类 Fenton 过程处理含有还原有机物质的废水方面可能具有潜在意义。
