The adsorption behaviour of Pb(II) ions from aqueous solution has been successfully tested by magnetic activated carbon prepared from novel adsorbent such as Citrus hystrix leaves (MCHLAC) by co-precipitation method and followed by thermal activation. The optimum contact time for the removal Pb(II) ions onto MCHLAC is found to be 90 min, and the optimum pH ranged from 5.0–7.0 respectively. The functionality, surface morphology and elemental composition of MCHLAC have been explored by FTIR, SEM and EDX analysis. The equilibrium data agree well with Langmuir model, which confirm the monolayer coverage of Pb(II) ions onto MCHLAC and the maximum monolayer adsorption capacity is 345.65 mg g-1. The kinetic data follow by pseudo-second order model with film diffusion process. Thermodynamic studies indicate that the process of uptake of lead(II) ions is spontaneous and exothermic. A single –stage batch adsorber is designed using the Langmuir adsorption isotherm equation. The regeneration study show that MCHLAC could be effectively utilized for the removal of Pb(II) ions for seven cycles of operation.

中文翻译：

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从柑橘（青柠或 Kolumichai）叶中合成磁性活性炭，对电镀废水具有优异的 Pb(II) 吸附性能

采用新型吸附剂如柑桔叶 (MCHLAC) 制备磁性活性炭，通过共沉淀法和热活化法成功地测试了水溶液中 Pb(II) 离子的吸附行为。发现在 MCHLAC 上去除 Pb(II) 离子的最佳接触时间为 90 分钟，最佳 pH 范围分别为 5.0-7.0。已通过 FTIR、SEM 和 EDX 分析探索了 MCHLAC 的功能、表面形态和元素组成。平衡数据与Langmuir模型吻合良好，证实了Pb(II)离子在MCHLAC上的单层覆盖，最大单层吸附容量为345.65 mg g-1。动力学数据遵循具有膜扩散过程的伪二级模型。热力学研究表明，铅 (II) 离子的吸收过程是自发的和放热的。使用朗缪尔吸附等温方程设计了一个单级间歇吸附器。再生研究表明，MCHLAC 可有效用于去除 Pb(II) 离子的七个操作周期。