Advances in the regulation of non-free radical pathways in persulfate systems

doi:10.16085/j.issn.1000-6613.2024-1441

Abstract

Abstract:

In recent years, peroxydisulfate-based advanced oxidation processes (PS-AOPs) have been widely used for the removal of organic pollutants from wastewater, and their water purification effects are closely related to the type of active oxygen species induced by catalysts. The PS-AOPs system can degrade pollutants through radical (·OH and ·SO₄^-) or non-radical (¹O₂, electron transfer, and high-valent metal species) pathways. However, there are problems with the non-selective existence of radicals in heterogeneous systems, short action time, easy reaction with halogen ions to generate toxic by-products, and the consumption of radicals by various interfering ions (such as OH^-, Cl^-, CO₃^2-) in wastewater, which reduces the amount of radicals acting on organic pollutants and affects the treatment effect. The high selectivity of non-radicals for electron-rich pollutants and insensitivity to halogen ions make them the focus of current research. However, there is no systematic review on the catalyst structure/property and non-radical pathway regulation in PS-AOPs systems at home and abroad. Based on this, this paper introduced the characteristics, generation mechanisms, and identification methods of the ¹O₂, electron transfer, and high-valent metal species three typical non-radical pathways, summarized the three methods and mechanisms of reducing the size of the catalyst active site, introducing heteroatoms into the catalyst, and changing the physical and chemical properties of the catalyst to achieve non-radical directed regulation, and finally outlined the directions of non-radical regulation to enhance catalyst stability, improve the method of distinguishing between radical/non-radical contributions, clarify the mechanism of non-radical species oxidizing organic pollutants, and deeply study the generation pathway or pollutant degradation pathway, in order to provide theoretical support for the efficient activation of non-radical pathways for PS to degrade organic pollutants.

Key words: catalyst activation, heterogeneous reaction, advanced oxidation, non-free radical, directional regulation and control, singlet oxygen, high-value metal

摘要：

近年来，过硫酸盐基高级氧化技术（PS-AOPs）已被广泛用于废水中有机污染物的去除，其净水效果与催化剂诱导的活性氧物种类型密切相关。PS-AOPs体系可通过自由基路径（·OH和·SO₄^-等）或非自由基路径（¹O₂、电子转移和高价金属种等）降解污染物。自由基在非均相体系中存在无选择性、作用时间短、易于与卤素离子反应生成有毒副产物等问题，且废水中的多种干扰离子（如OH^-、Cl^-、CO₃^2-等）会消耗自由基，减少其与有机污染物的作用量，从而影响处理效果。非自由基对富电子污染物的高选择性以及对卤素离子不敏感等优点使其成为当下研究热点。然而，国内外还没有针对催化剂结构/性质与PS-AOPs体系中非自由基路径调控的系统综述。基于此，本文介绍了¹O₂、电子转移和高价金属种三种典型非自由基路径的特点、生成机制及鉴定方法，并概括了缩小催化剂活性位点尺寸、在催化剂中引入杂原子和改变催化剂物理化学特性三种实现非自由基定向调控的方法及机理，最后展望了非自由基调控应往提升催化剂稳定性、完善自由基/非自由基贡献度区分方法、明确非自由基物种氧化有机污染物的机制以及深入研究活性物种生成路径或污染物降解路径的方向发展，为实现非自由基路径高效活化PS降解有机污染物提供理论依据。

关键词: 催化剂活化, 多相反应, 高级氧化, 非自由基, 定向调控, 单线态氧, 高价金属

CLC Number:

HU Zhixuan, XIONG Ting, JIANG Longbo, YUAN Xingzhong. Advances in the regulation of non-free radical pathways in persulfate systems[J]. Chemical Industry and Engineering Progress, 2025, 44(10): 5975-5990.

胡芝璇, 熊婷, 蒋龙波, 袁兴中. 过硫酸盐体系中非自由基路径的调控研究进展[J]. 化工进展, 2025, 44(10): 5975-5990.

Figures/Tables 6

催化剂类型	催化剂	非自由基路径	活性位点	实验条件	催化效率	参考文献
过渡金属基催化剂	Co、N掺杂石墨碳（CZIF）	¹O₂	Co³⁺和Co⁰、石墨N、吡咯N、酮基（C $̿$ O）	[催化剂]₀=0.05g/L，[卡马西平]₀=5mg/L， [PMS]₀=0.4mmol/L	96.8%	[14]
	CuO和钴/氮掺杂的碳质框架（Cu@Co-N-C）	¹O₂、电子转移	Cu和Co位点、羟基（—OH）、酮基（C $̿$ O）	[催化剂]₀=0.025g/L，[萘普生]₀=11.5mg/L， [PMS]₀=0.5mmol/L	100%	[15]
	生物炭铜单原子催化剂（SACu30@NC）	电子转移	Cu(Ⅰ)、Cu(Ⅱ)和Cu(Ⅲ)	[催化剂]₀=0.1g/L，[双酚A]₀=20mg/L， [PDS]₀=0.2g/L	100%	[16]
	二元金属-有机骨架衍生的催化剂（Mn-Co₃O₄）	（中性和酸性）电子转移、¹O₂、高价钴氧	Co和Mn位点、氧空位	[催化剂]₀=0.05g/L，[磺胺甲𫫇唑]₀=10mg/L， [PDS]₀=0.5mmol/L	100%	[17]
	含铁氮化碳（Fe-CN）单原子催化剂	¹O₂、高价铁氧	Fe-N₃O₁位点	[催化剂]₀=0.1g/L，[磺胺甲𫫇唑]₀=10mg/L， [PMS]₀=1mmol/L	99.97%	[18]
	FeO和Fe₂O₃	¹O₂、高价铁氧	FeO（220）	[催化剂]₀=0.1g/L，[四环素]₀=20mg/L， [PMS]₀=0.1g/L	99%	[19]
碳基催化剂	氮掺杂的碳化聚苯胺（N-CPANI）	¹O₂、电子转移	石墨N、酮基（C $̿$ O）、缺陷位点	[催化剂]₀=0.75g/L，[强力霉素]₀=20mg/L， [PDS]₀=0.5g/L	91.66%	[20]
	石墨化氮掺杂生物炭纤维（PGBF-N）	¹O₂、电子转移	酮基（C $̿$ O）、石墨N、碳网络上的缺陷位点	[催化剂]₀=0.1g/L，[四环素]₀=20mg/L， [PMS]₀=1mmol/L	96.5%	[21]
	氮掺杂多孔碳材料（NPCs）	¹O₂、电子转移	石墨N、sp²杂化碳	[催化剂]₀=0.1g/L，[罗丹明B]₀=50mg/L， [PMS]₀=0.3g/L	99.25%	[22]
	富氮层系多孔石墨碳（NHC）	¹O₂、电子转移	缺陷边、酮基（C $̿$ O）、石墨N、吡啶N	[催化剂]₀=0.05g/L，[四环素]₀=20mg/L， [PDS]₀=5mmol/L	94.4%	[23]

催化剂类型	催化剂	非自由基路径	活性位点	实验条件	催化效率	参考文献
过渡金属基催化剂	Co、N掺杂石墨碳（CZIF）	¹O₂	Co³⁺和Co⁰、石墨N、吡咯N、酮基（C $̿$ O）	[催化剂]₀=0.05g/L，[卡马西平]₀=5mg/L， [PMS]₀=0.4mmol/L	96.8%	[14]
	CuO和钴/氮掺杂的碳质框架（Cu@Co-N-C）	¹O₂、电子转移	Cu和Co位点、羟基（—OH）、酮基（C $̿$ O）	[催化剂]₀=0.025g/L，[萘普生]₀=11.5mg/L， [PMS]₀=0.5mmol/L	100%	[15]
	生物炭铜单原子催化剂（SACu30@NC）	电子转移	Cu(Ⅰ)、Cu(Ⅱ)和Cu(Ⅲ)	[催化剂]₀=0.1g/L，[双酚A]₀=20mg/L， [PDS]₀=0.2g/L	100%	[16]
	二元金属-有机骨架衍生的催化剂（Mn-Co₃O₄）	（中性和酸性）电子转移、¹O₂、高价钴氧	Co和Mn位点、氧空位	[催化剂]₀=0.05g/L，[磺胺甲𫫇唑]₀=10mg/L， [PDS]₀=0.5mmol/L	100%	[17]
	含铁氮化碳（Fe-CN）单原子催化剂	¹O₂、高价铁氧	Fe-N₃O₁位点	[催化剂]₀=0.1g/L，[磺胺甲𫫇唑]₀=10mg/L， [PMS]₀=1mmol/L	99.97%	[18]
	FeO和Fe₂O₃	¹O₂、高价铁氧	FeO（220）	[催化剂]₀=0.1g/L，[四环素]₀=20mg/L， [PMS]₀=0.1g/L	99%	[19]
碳基催化剂	氮掺杂的碳化聚苯胺（N-CPANI）	¹O₂、电子转移	石墨N、酮基（C $̿$ O）、缺陷位点	[催化剂]₀=0.75g/L，[强力霉素]₀=20mg/L， [PDS]₀=0.5g/L	91.66%	[20]
	石墨化氮掺杂生物炭纤维（PGBF-N）	¹O₂、电子转移	酮基（C $̿$ O）、石墨N、碳网络上的缺陷位点	[催化剂]₀=0.1g/L，[四环素]₀=20mg/L， [PMS]₀=1mmol/L	96.5%	[21]
	氮掺杂多孔碳材料（NPCs）	¹O₂、电子转移	石墨N、sp²杂化碳	[催化剂]₀=0.1g/L，[罗丹明B]₀=50mg/L， [PMS]₀=0.3g/L	99.25%	[22]
	富氮层系多孔石墨碳（NHC）	¹O₂、电子转移	缺陷边、酮基（C $̿$ O）、石墨N、吡啶N	[催化剂]₀=0.05g/L，[四环素]₀=20mg/L， [PDS]₀=5mmol/L	94.4%	[23]

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