Hubei Key Laboratory of Mineral Resources Processing and Environment, School of Resources and Environmental Engineering, State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan 430070, China.
China-UK Water and Soil Resources Sustainable Utilization Joint Research Centre, Farmland Irrigation Research Institute, Chinese Academy of Agricultural Sciences, Xinxiang 453002, China.
J Hazard Mater. 2021 Apr 5;407:124777. doi: 10.1016/j.jhazmat.2020.124777. Epub 2020 Dec 5.
Environmental concentration imidacloprid (IMI) has become a potential risk to ecological safety and human health, therefore an efficient, sustainable and environment friendly approach was urgently needed for its removal. In this study, a novel graphene oxide supported magnetic sludge biochar composite (GO/CoFeO-SBC) was first time synthesized and assessed for IMI removal at environmental concentration level. The maximum adsorption capacity of GO/CoFeO-SBC for IMI was 8.64 × 10 μg g. Physicochemical characteristics, kinetics (pseudo-second-order), isotherms (Freundlich and Temkin), thermodynamics and environmental factors analysis suggested that its outstanding adsorption performance was mainly attributed to pore filling, π-π conjugation and functional groups interaction. The mechanisms analysis indicated that intraparticle diffusion was the main rate-limiting step and its adsorption was a spontaneous, endothermic and randomness increased process. The magnetic sensitivity enabled it to be easily separated from water. The sustainable adsorption capacity (>90% of the initial adsorption capacity) of GO/CoFeO-SBC was well maintained by ethanol extraction even after five reuse cycles. GO/CoFeO-SBC also exhibited environmental security with its leaching concentrations of Fe and Co were below 0.5 mg L in a wide pH range. The performance of GO/CoFeO-SBC suggested that it could be served as a promising adsorbent for environmental concentration IMI removal.
环境浓度吡虫啉（IMI）对生态安全和人类健康已构成潜在风险，因此急需寻找一种高效、可持续且环境友好的方法来去除它。在本研究中，首次合成了一种新型的氧化石墨烯负载磁性污泥生物炭复合材料（GO/CoFeO-SBC），并评估了其在环境浓度水平下对 IMI 的去除能力。GO/CoFeO-SBC 对 IMI 的最大吸附容量为 8.64×10μg g。物理化学特性、动力学（拟二级）、等温线（Freundlich 和 Temkin）、热力学和环境因素分析表明，其优异的吸附性能主要归因于孔填充、π-π 共轭和官能团相互作用。机理分析表明，内扩散是主要的速率限制步骤，其吸附是一个自发、吸热和随机性增加的过程。磁性使其能够很容易地从水中分离出来。即使经过五次重复使用循环，乙醇萃取也能很好地保持 GO/CoFeO-SBC 的可持续吸附容量（>初始吸附容量的 90%）。GO/CoFeO-SBC 在很宽的 pH 范围内浸出的铁和钴浓度均低于 0.5mg L，具有环境安全性。GO/CoFeO-SBC 的性能表明，它可用作去除环境浓度 IMI 的一种有前途的吸附剂。
