中国科学院过程工程研究所崔彦斌研究团队报道了磁性活性炭吸附及类芬顿降解去除水中甲基橙。相关研究成果发表在2024年9月8日出版的《颗粒学报》。

有机染料造成的水污染是一个重要的环境问题。尽管活性炭（AC）通常用于染料吸附，但其有效性受到分离和再生挑战的限制。

为了解决这些局限性，研究人员通过共沉淀和煅烧方法制备了一种方便的可回收磁性活性炭（MAC），作为通过芬顿样降解过程去除甲基橙（MO）的吸附剂和催化剂。XRD、FTIR、SEM和TEM等表征技术证实，Fe₃O₄纳米粒子（10-20nm）均匀分散在AC表面。MAC保持高表面积（997 m²/g）和孔体积（0.795 cm³/g），并表现出超顺磁性，饱和磁化强度为5.52 emu/g，能够通过磁体有效地与水溶液分离。

批量吸附研究表明，MO在MAC上的吸附遵循伪二级动力学和Freundlich等温线模型，在25°C下的最大吸附容量为205mg/g。热力学分析表明，吸附过程是自发的、吸热的。通过使用过硫酸钠（PS）的Fenton样反应实现了MO的同时降解和MAC的原位再生。在PS浓度为9mmol/L时，60分钟后MO去除率接近95%，总有机碳（TOC）减少83.1%。Fe₃O₄和AC表面上的氧官能团与PS的反应促进了MO的产生，从而增强了MO的催化降解。降解效率随着温度从25°C升高到45°C而提高。循环试验表明，经过5个循环的再生后，MAC的MO去除效率保持在90%以上。

总的来说，该项研究强调了MAC通过吸附和芬顿样降解的耦合，有效去除水中有机染料的潜力，为解决水污染挑战提供了一种有前景的解决方案。

附：英文原文

Title: Magnetic activated carbon for the removal of methyl orange from water via adsorption and Fenton-like degradation

Author: Qianyu Wang,Yuming Zhang,Yuhua Zheng,Emmanuel Oluwaseyi Fagbohun,Yanbin Cui

Issue&Volume: 2024-09-08

Abstract: Water pollution caused by organic dyes is a critical environmental issue. Although activated carbon (AC) is commonly used for dye adsorption, its effectiveness is limited by challenges in separation and regeneration. To address these limitations, a convenient recyclable magnetic activated carbon (MAC) was fabricated via co-precipitation and calcination method, serving as adsorbent and catalyst for methyl orange (MO) removal through a Fenton-like degradation process. Characterization techniques, including XRD, FTIR, SEM and TEM, confirmed that Fe3O4 nanoparticles (10-20 nm) were uniformly dispersed on AC surface. The MAC maintaining a high surface area (997 m2/g) and pore volume (0.795 cm3/g) and exhibited superparamagnetic properties with a saturated magnetization of 5.52 emu/g, enabling effective separation from aqueous solutions by magnet. Batch adsorption studies revealed that MO adsorption onto MAC followed pseudo-second-order kinetic and Freundlich isotherm model, with a maximum adsorption capacity of 205 mg/g at 25 °C. Thermodynamic analysis showed that the adsorption process was spontaneous and endothermic. Simultaneous degradation of MO and in-situ regeneration of MAC were achieved via Fenton-like reaction using sodium persulfate (PS). Under a PS concentration of 9 mmol/L, the MO removal efficiency near 95% after 60 min, with a total organic carbon (TOC) reduction of 83.1%. The reaction of Fe3O4 and oxygen functional groups on AC surface with PS facilitated the generation of , thereby enhancing catalytic degradation of MO. The degradation efficiency improved as the temperature increased from 25 °C to 45 °C. Cycle tests demonstrated that the MO removal efficiency of MAC remained above 90% after 5 cycles of regeneration. Overall, this study highlights the potential of MAC for efficient removal of organic dyes from water through the coupling of adsorption and Fenton-like degradation, providing a promising solution for addressing water pollution challenges.

DOI: 10.1016/j.partic.2024.08.014

Source: https://www.sciencedirect.com/science/article/abs/pii/S167420012400169X