College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China.
College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China.
J Hazard Mater. 2021 May 5;409:124893. doi: 10.1016/j.jhazmat.2020.124893. Epub 2021 Jan 5.
In the last decade, more and more refractory organic contaminants with severe health risks have been detected in the aquatic ecosystem. Sulfate radical (SO)-based advanced oxidation process (SR-AOP) is recognized as an efficient approach for the removal of organic contaminants. Biochar (BC) and its composites (BCs) have been applied into SR-AOP for the double advantages of adsorption and catalytic ability. This paper gives systematic emphasis to the development and progress of biochar and its composites as catalyst in persulfate-advanced oxidation process. Synthetic techniques including the directed pyrolysis of mixed materials and post-immersed method are discussed. The physicochemical properties of biochar (such as surface area, surface functional groups, defect structure and persistent free radicals, etc.) that affect persulfate activation are provided. Then, emphasis is placed on the crucial role of biochar in affecting the catalytic property of BCs including stabilizing nanoparticles, expanding the surface area, increasing active sites and regulating electron transfer reactions. Integrating mechanistic insights and different biochar-based catalysts highlight the understanding of persulfate activation and catalytic degradation. Possible challenges are finally proposed in the fundamental research and practically scaled-up application.
在过去的十年中，越来越多的具有严重健康风险的难处理有机污染物在水生生态系统中被检测到。基于硫酸根自由基（SO 4 -）的高级氧化工艺（SR-AOP）被认为是去除有机污染物的有效方法。生物炭（BC）及其复合材料（BCs）已被应用于 SR-AOP，兼具吸附和催化能力的双重优势。本文系统地强调了生物炭及其复合材料作为过硫酸盐高级氧化工艺催化剂的发展和进展。讨论了包括定向热解混合材料和后浸渍法在内的合成技术。提供了影响过硫酸盐活化的生物炭的物理化学性质（如表面积、表面官能团、缺陷结构和持久自由基等）。然后，重点介绍了生物炭在影响包括稳定纳米颗粒、扩大表面积、增加活性位点和调节电子转移反应在内的 BC 催化性能方面的关键作用。整合机理见解和不同的基于生物炭的催化剂突出了对过硫酸盐活化和催化降解的理解。最后在基础研究和实际规模化应用方面提出了可能的挑战。
