Lv Xin, Zhou Chenying, Shen Zhichao, Zhang Yuchen, He Chuanshu, Du Ye, Xiong Zhaokun, Huang Rongfu, Zhou Peng, Lai Bo
State Key Laboratory of Hydraulics and Mountain River Engineering, College of Architecture & Environment, Sichuan University, Chengdu 610065, China; Sino-German Centre for Water and Health Research, Sichuan University, Chengdu 610065, China.
Sichuan Development Environmental Science and Technology Research Institute, Chengdu 610095, China.
J Hazard Mater. 2023 Sep 15;458:132040. doi: 10.1016/j.jhazmat.2023.132040. Epub 2023 Jul 12.
The acceleration of Fe(III)/Fe(II) conversion in Fenton systems is the critical route to achieve the long-lasting generation of reactive oxygen species towards the oxidation of refractory contaminants. Here, we found that waste leather derived porous carbon materials (LPC), as a simple and readily available metal-free biochar material, can promote the Fe(III)/HO system to generate hydroxyl radicals (OH) for oxidizing a broad spectrum of contaminants. Results of characterizations, theoretical calculations, and electrochemical tests show that the surface carbonyl groups of LPC can provide electron for direct Fe(III) reduction. More importantly, the graphitic-N on surface of LPC can enhance the reactivity of Fe(III) for accelerating HO induced Fe(III) reduction. The presence of LPC accelerates the Fe(III)/Fe(II) redox cycle in the Fe(III)/HO system, sustainable Fenton chain reactions is thus initiated for long-lasting generation of hydroxyl radicals without adding Fe(II). The continuous flow mode that couples in-situ Fenton-like oxidation and LPC with excellent adsorption catalytic properties, anti-coexisting substances interference and reusability performance enables efficient, green and sustainable degradation of trace organic pollutants. Therefore, the application of metal-free carbon materials in Fenton-like system can solve its rate-limiting problem, reduce the production of iron sludge, achieve green Fenton chemistry, and facilitate the actual engineering application of economic and ecological methods to efficiently remove trace organic contaminants from actual water sources.
芬顿体系中Fe(III)/Fe(II)转化的加速是实现活性氧长期生成以氧化难降解污染物的关键途径。在此，我们发现源自废皮革的多孔碳材料（LPC），作为一种简单且易于获得的无金属生物炭材料，可促进Fe(III)/HO体系生成羟基自由基（·OH）以氧化多种污染物。表征、理论计算和电化学测试结果表明，LPC的表面羰基可为直接还原Fe(III)提供电子。更重要的是，LPC表面的石墨氮可增强Fe(III)的反应活性，加速·OH诱导的Fe(III)还原。LPC的存在加速了Fe(III)/HO体系中的Fe(III)/Fe(II)氧化还原循环，从而在不添加Fe(II)的情况下引发可持续的芬顿链式反应以长期生成羟基自由基。将原位类芬顿氧化与具有优异吸附催化性能、抗共存物质干扰和可重复使用性能的LPC相结合的连续流动模式，能够高效、绿色且可持续地降解痕量有机污染物。因此，无金属碳材料在类芬顿体系中的应用可解决其限速问题，减少铁泥的产生，实现绿色芬顿化学，并促进经济且生态的方法在实际工程中应用，以高效去除实际水源中的痕量有机污染物。
