In recent years, activation of sodium percarbonate (SPC) has been regarded as very appealing technologies in the elimination of organic pollutants. In this work, the activation of SPC using micro amounts of Cu(II) (at μM level) towards acid orange 7 (AO7) degradation was explored. Experimental results displayed that nearly 97.5% of AO7 could be removed within 15 min using 20 µM Cu(II) and 0.4 mM SPC. Effects of Cu(II) concentration, SPC concentration, pH value and coexisting anions were investigated. Compared with conventional Fenton oxidation, which could only work under acidic pH conditions, Cu(II)-catalyzed SPC (Cu(II) /SPC) system could work under near-neutral or alkaline solutions. Furthermore, AO7 decomposition was barely impacted by Cl⁻, SO₄²⁻ and NO₃⁻, while 5 mM HCO₃⁻ inhibited the degradation of AO7. Electron paramagnetic resonance analysis confirmed the existence of multiple reactive oxygen species in the reaction (HO^•, O₂^•–, ¹O₂). However, free radical scavenging experiments demonstrated that the degradation of AO7 was mainly due to the carbonate radicals (CO₃^•−) and singlet oxygen (¹O₂). The interaction between Cu(I) and Cu(II) was confirmed and the production of Cu(III) was proved to act as a degradation agent for AO7. The degradation of AO7 could be divided into two pathways. The study suggests a simple, economic and efficient technique for dye wastewater treatment using SPC triggered by micro-amount Cu(II).

近年来，过碳酸钠活化（SPC）被认为是消除有机污染物中非常有吸引力的技术。在这项工作中，探索了使用微量 Cu(II)（μM 水平）激活 SPC 来降解酸性橙 7 (AO7)。实验结果表明，使用 20 µM Cu(II) 和 0.4 mM SPC 可以在 15 分钟内去除近 97.5% 的 AO7。研究了Cu(II)浓度、SPC浓度、pH值和共存阴离子的影响。与只能在酸性pH条件下工作的传统芬顿氧化相比，Cu(II)催化的SPC（Cu(II) /SPC）系统可以在接近中性或碱性溶液下工作。此外，AO7的分解几乎不受Cl ^-、SO ₄ ²⁻和NO _3的影响⁻，而5 mM HCO ₃ ⁻抑制AO7 的降解。电子顺磁共振分析证实反应中存在多种活性氧（HO ^•、O ₂ ^•–、¹ O ₂）。然而，自由基清除实验表明，AO7的降解主要是由于碳酸盐自由基（CO ₃ ^•−）和单线态氧（¹ O ₂）。证实了 Cu(I) 和 Cu(II) 之间的相互作用，并且证明 Cu(III) 的产生可作为 AO7 的降解剂。AO7的降解可分为两条途径。该研究提出了一种简单、经济且高效的利用微量 Cu(II) 引发的 SPC 处理染料废水的技术。