This study reports the facile synthesis of cubic spinel-type manganese ferrite (MnFe₂O₄)/biochar (MF/BC) composites via a one-pot hydrothermal technique. Multiple characterizations demonstrated that the MnFe₂O₄ spinel nanoparticles were successfully grown on the biochar, which provides magnetic separability with superparamagnetic behavior and effective adsorption performance for heavy metals (Pb(II), Cu(II), and Cd(II)). The adsorption kinetics and isotherms can be well described with a pseudo-second-order and Sips isotherm models, respectively. Comparative adsorption in multi-heavy metal systems (binary and ternary) indicated that the adsorption affinity of MF/BC composites toward heavy metals followed the sequence of Pb(II) > Cu(II) > Cd(II), which followed the order of their covalent indexes. Thermodynamic analysis revealed that the adsorption process was endothermic and primarily governed by physisorption. This study provides a feasible and simple approach for the preparation of high-performance materials for the remediation of heavy metal-contaminated wastewater in a cost-effective manner.

这项研究报告了通过一锅水热技术容易地合成立方尖晶石型锰铁氧体（MnFe ₂ O ₄）/生物炭（MF / BC）复合材料。多重表征表明，MnFe ₂ O ₄尖晶石纳米颗粒在生物炭上成功生长，该生物炭提供了具有超顺磁性行为的磁可分离性以及对重金属（Pb（II），Cu（II）和Cd（II））的有效吸附性能。吸附动力学和等温线可以分别用伪二级和Sips等温线模型很好地描述。在多重金属系统（二元和三元）中的比较吸附表明，MF / BC复合物对重金属的吸附亲和力遵循Pb（II）> Cu（II）> Cd（II）的顺序，顺序为它们的共价指数。热力学分析表明，吸附过程是吸热的，主要受物理吸附作用。