A novel adsorbent of Mg/Al-LDH functionalized magnetic biochar from waste poplar sawdust (CoFe₂O₄@PBC-LDH) and bamboo powder (CoFe₂O₄@BBC-LDH) was developed, and the removal performance of HA from aqueous solution was investigated. The Mg/Al-LDH was effectively functionalized on the CoFe₂O₄@BC surface via co-precipitation method. The CoFe₂O₄@BC-LDH exhibited a brush structure with larger surface area and higher adsorption capability. The adsorption mechanism was mainly the ions exchange and electrostatic interactions between CoFe₂O₄@BC-LDH and HA. The adsorption of HA was well fitted to the Freundlich model with endothermic nature and spontaneous process. CoFe₂O₄@BC-LDH showed remarkable adsorption capacity for HA, and the maximum adsorption capacity for CoFe₂O₄@PBC-LDH and CoFe₂O₄@BBC-LDH were 240.58 and 337.83 mg·g⁻¹ at 25 °C, respectively. The adsorption process was conformed to the pseudo-second-order model and dominated by the chemisorption. Meanwhile, the coexisting ions could conducive to the adsorption capacity of CoFe₂O₄@BC-LDH for HA. Most importantly, CoFe₂O₄@BC-LDH exhibited an excellent adsorption capacity in real water samples with long-term stability, and which can be easily recycled from water under an external magnet. Therefore, this work provides new insights into the fabrication of low-cost biochar from forestry wastes and that can be used to develop a high-performance adsorbent for removal of contaminants.

开发了一种从废杨木屑 (CoFe ₂ O ₄ @PBC-LDH) 和竹粉 (CoFe ₂ O ₄ @BBC-LDH) 中提取 Mg/Al-LDH 功能化磁性生物炭的新型吸附剂，并研究了从水溶液中去除 HA 的性能解决方案进行了调查。Mg/Al-LDH通过共沉淀法在 CoFe ₂ O ₄ @BC 表面有效地功能化。CoFe ₂ O ₄ @BC-LDH 呈现出具有更大表面积和更高吸附能力的刷状结构。吸附机理主要是CoFe ₂ O ₄之间的离子交换和静电相互作用。@BC-LDH 和 HA。HA 的吸附非常适合具有吸热性质和自发过程的 Freundlich 模型。CoFe ₂ O ₄ @BC-LDH对HA表现出显着的吸附能力，在25°时对CoFe ₂ O ₄ @PBC-LDH和CoFe ₂ O ₄ @BBC-LDH的最大吸附能力分别为240.58和337.83 mg·g ^-1 C、分别。吸附过程符合准二级模型，以化学吸附为主。同时，共存离子有助于提高CoFe ₂ O ₄ @BC-LDH对HA的吸附能力。最重要的是，CoFe ₂ O ₄@BC-LDH 在真实水样中表现出优异的吸附能力，具有长期稳定性，并且可以在外部磁铁下轻松地从水中回收。因此，这项工作为从林业废物制造低成本生物炭提供了新的见解，并可用于开发高性能吸附剂以去除污染物。