College of Chemical Engineering, Huaqiao University, Xiamen 361021, China.
College of Chemical Engineering, Huaqiao University, Xiamen 361021, China.
Water Res. 2022 Aug 15;222:118930. doi: 10.1016/j.watres.2022.118930. Epub 2022 Aug 1.
Recently, iron-based heterogenous catalysts have received much attention in the activation of peracetic acid (PAA) for generating reactive radicals to degrade organic pollutants, yet the PAA activation efficiency is compromised by the slow transformation from Fe(III) to Fe(II). Herein, considering the electron-donating ability of reducing sulfur species, a novel advanced oxidation process by combining pyrite and PAA (simplified as pyrite/PAA) for the abatement of tetracycline (TC) is proposed in this study. In the pyrite/PAA process, TC can be completely removed within 30 min under neutral conditions by the synergy of homogeneous and heterogenous Fe(II) species. CHC(O)OO• is the main radical generated from the pyrite/PAA process responsible for TC abatement. The excellent activation properties of pyrite can be attributed to the superior electron-donating ability of reducing sulfur species to facilitate the reduction of Fe(III). Meanwhile, the complexation of leached Fe with TC favors PAA activation and concomitant TC abatement. In addition, the degradation pathways of TC and the toxicity of the degradation intermediates are analyzed. The pyrite/PAA process shows an excellent TC abatement efficacy in the pH range of 4.0∼10.0. The coexistence of Cl, HCO, and HPO exhibits negligible effect on TC abatement, while the HA slightly inhibits the abatement rate of TC. This study highlights the efficient activation of PAA by pyrite and the important role of sulfur in promoting the conversion of Fe(III) to Fe(II) in the pyrite/PAA process.
最近，铁基多相催化剂在过氧乙酸（PAA）活化方面受到了广泛关注，因为它可以产生活性自由基来降解有机污染物，但 PAA 的活化效率受到 Fe(III)向 Fe(II)缓慢转化的限制。在此，考虑到还原硫物种的供电子能力，本研究提出了一种将黄铁矿与 PAA 结合（简称为黄铁矿/PAA）的新型高级氧化工艺，用于去除四环素（TC）。在黄铁矿/PAA 工艺中，在中性条件下，TC 可以在 30 min 内完全去除，这是由均相和多相 Fe(II)物种的协同作用实现的。CHC(O)OO•是黄铁矿/PAA 工艺中生成的主要自由基，负责 TC 的去除。黄铁矿优异的活化性能可归因于还原硫物种优越的供电子能力，促进了 Fe(III)的还原。同时，TC 与浸出的 Fe 形成复合物有利于 PAA 的活化和伴随的 TC 去除。此外，还分析了 TC 的降解途径和降解中间产物的毒性。黄铁矿/PAA 工艺在 pH 值为 4.0∼10.0 的范围内对 TC 具有优异的去除效果。Cl、HCO 和 HPO 的共存对 TC 的去除几乎没有影响，而 HA 则略微抑制了 TC 的去除速率。本研究强调了黄铁矿对 PAA 的高效活化作用以及硫在促进黄铁矿/PAA 工艺中 Fe(III)向 Fe(II)转化中的重要作用。
