Due to the high biotoxicity and persistence of polycyclic aromatic hydrocarbons (PAHs), the remediation of PAHs-contaminated soil becomes an intractable problem. Persulfate-based advanced oxidation processes are widely used to degrade PAHs in aquatic environment. However, they are not convenient for used in soil due to the heterogeneity and complexity of soil matrix. In this study, a green and convenient ball milling process is introduced to activate persulfate for the remediation of PAHs-contaminated soil. About 82.5% PAHs were removed with 10% wt. NaSO (PS) addition and ball-milling for 2 h under 500 r/min. The degradation of PAHs is attributed to the attack of radicals (SO· and·OH) generated from the activation of PS by mechanochemistry. Moreover, stable Si-O bonds were disrupted during ball-milling process, and formed free electron on the surface of soil particles. This facilitates the electron transfer from oxidants to contaminants. The particle size, surface element composition, functional group, and thermogravimetric analysis confirmed the slight disturbance of ball-milling-assisted PS process on the physical and chemical properties of soil. Therefore, ball-milling assisted PS approach would be a promising technology for the remediation of PAHs-contaminated soil.

中文翻译：

---

固体过硫酸盐绿色机械化学活化去除土壤中多环芳烃：性能与机理


由于多环芳烃（PAHs）的高生物毒性和持久性，PAHs污染土壤的修复成为一个棘手的问题。基于过硫酸盐的高级氧化工艺广泛用于降解水生环境中的多环芳烃。然而，由于土壤基质的异质性和复杂性，它们不方便在土壤中使用。本研究引入了一种绿色便捷的球磨工艺来活化过硫酸盐，用于修复多环芳烃污染的土壤。约 82.5% 的 PAH 被 10% wt 去除。添加 NaSO (PS)，并在 500 r/min 下球磨 2 小时。 PAHs的降解归因于PS通过机械化学作用激活而产生的自由基（SO·和·OH）的攻击。此外，稳定的Si-O键在球磨过程中被破坏，并在土壤颗粒表面形成自由电子。这有利于电子从氧化剂转移到污染物。粒径、表面元素组成、官能团和热重分析证实了球磨辅助PS过程对土壤理化性质的轻微干扰。因此，球磨辅助PS方法将是修复PAHs污染土壤的一种有前途的技术。