Abstract

In the present study, an adsorption method exploiting synthetic and natural adsorbents was utilized for removing cobalt ions from aqueous solutions. First, the nanocomposite synthetic adsorbent containing Fe₃O₄ magnetic particles stabilized by cetyltrimethylammonium bromide (CTAB) was synthesized and then, the sample was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and nitrogen adsorption and desorption isotherms (BET). The impacts of various operating parameters (adsorbate concentration, pH, adsorbent dose, contact time, and stirring speed) were also investigated. The results indicated that the pseudo-second order kinetic model can well fit the experimental values of cobalt ion removal from aqueous solution for both adsorbents. Gibbs free energy, enthalpy and entropy were also calculated which revealed that the adsorption behavior for both adsorbents is chemical, endothermic and spontaneous. Moreover, the equilibrium data were fitted with Langmuir, Freundlich, Temkin and Dubinin-Radushkevich equilibrium isotherms. Accordingly, CO²⁺ adsorption on both nanocomposite and Typha latifolia L. followed the Langmuir isotherm model. The maximum amount of the cobalt ion removal by nanocomposite and Typha latifolia L. adsorbents was evaluated to be 196.07 and 107.52 mg/g of adsorbent, respectively.

中文翻译：

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含有 CTAB 稳定的 Fe3O4 磁性纳米颗粒的纳米复合材料的合成及钴离子在纳米复合材料和香蒲的吸附行为的比较。

摘要

在本研究中，利用合成和天然吸附剂的吸附方法用于从水溶液中去除钴离子。_{一、含有Fe 3} O ₄的纳米复合合成吸附剂合成了十六烷基三甲基溴化铵（CTAB）稳定的磁性颗粒，然后对样品进行了X射线衍射（XRD）、傅里叶变换红外光谱（FTIR）、能量色散X射线光谱（EDX）、扫描电子显微镜（ SEM)、透射电子显微镜 (TEM) 和氮吸附和解吸等温线 (BET)。还研究了各种操作参数（吸附物浓度、pH、吸附剂剂量、接触时间和搅拌速度）的影响。结果表明，准二级动力学模型可以很好地拟合两种吸附剂从水溶液中去除钴离子的实验值。还计算了吉布斯自由能、焓和熵，这表明两种吸附剂的吸附行为是化学的、吸热的和自发的。此外，平衡数据符合 Langmuir、Freundlich、Temkin 和 Dubinin-Radushkevich 平衡等温线。因此，CO纳米复合材料和香蒲的²⁺吸附遵循 Langmuir 等温线模型。经评估，纳米复合材料和香蒲吸附剂去除钴离子的最大量分别为 196.07 和 107.52 mg/g 吸附剂。