Characterisation and reactivity of iron species in the Fenton reaction

芬顿反应是亚铁(Fe(II))与过氧化氢(H_2O_2)的反应。尽管这一反应早已广为人知，甚至在合适的pH条件下用于工业废水处理，但对各个反应步骤的详细过程理解仍然是空白。因此，在运行项目SCHM 2350/5-1的拟议后续项目中，我们希望继续芬顿反应的机理研究。重点分析了所涉及的中间体、铁-过氧络合物，以及在近中性pH(Fe(IV))下假定的反应物种。我们的研究重点既是活性物种的寿命，也是与选定的探针化合物的反应活性。对于前者，应系统地改变过氧化氢的浓度，如果是Fe2+/H2O2-络合物和Fe(IV)，则还应改变pH。后者的探针化合物是As(III)和富电子芳环。关于观察到的速率常数和生成的产物，铁络合剂的存在对Fenton反应有很大的影响。两者都应作为配体浓度和pH的函数进行研究。在第一阶段重点介绍了无机配体之后，我们现在将切换到有机配体。所获得的知识将示范应用于改善双酚S的降解，双酚是一种重要的工业化学品，已在废水处理中使用芬顿法消除。

The Fenton reaction is the reaction of ferrous iron (Fe(II) with hydrogen peroxide (H2O2). Although this reaction is well known for a long time and even used in industrial wastewater treatment under suitable pH conditions, a detailed process understanding of the individual reaction steps is still missing. In the proposed follow-up project to the running project SCHM 2350/5-1 we therefore want to continue the mechanistic study of the Fenton reaction. Emphasis is on the analysis of the involved intermediates, the iron-peroxo-complexes, as well as of the postulated reactive species at circumneutral pH, (Fe(IV)). In our research focus are both lifetimes of the reactive species and reactivities with selected probe compounds. For the former a systematic variation of the concentration of hydrogen peroxide and in case of the Fe2+/H2O2-complex and Fe(IV) also of pH shall be performed. The probe compounds for the latter are As(III) and electron-rich aromatic rings. The Fenton reaction is heavily influenced by the presence of iron-complexing agents with regard to the observed rate constant and the formed products. Both shall be investigated as a function of ligand concentration and pH. After a focus on inorganic ligands in the first phase, we will now switch to organic ligands. The gained knowledge shall be exemplarily applied for the improvement of the degradation of Bisphenol S, an important industrial chemical, for which elimination by the Fenton process is already used in wastewater treatment.