ABSTRACT

In this study, new activated carbons (ACs) were synthesized from a mixture of lemon and orange seeds (LOS) for toxic metal removal from aqueous solutions. Adsorbents have been produced by chemical activation with different activation agents (with H₃PO₄, ZnCl₂ and KOH) and activation temperature (600°C, 700°C, 800°C). The elemental analysis, FT-IR, XRD and SEM analyses were performed to determine the characterization of the ACs. A series of batch adsorption experiments were done to research the influence of various parameters such as pH, adsorbent dosage, contact time, temperature, the complexing agents on the toxic metal ions (Cu(II), Cr(III) and Ni(II)) removal capacity of ACs. Adsorption equilibration time was 60 min, the adsorption capacity was 118.02 mg/g for Ni(II) ions, 146.03 mg/g for Cr(III) ions and 150.45 mg/g for Cu(II) ions. The adsorption of toxic metal ions was observed as a maximum at pH = 5 on AC-ZnCl₂ (600°C) produced under N₂ atmosphere. The adsorption process was fitted with a Langmuir isotherm model and a pseudo-second-order kinetic equation, showing the metal ions adsorption on AC was monolayer coverage. Thermodynamic studies show that the adsorption is endothermic and spontaneous in nature. AC produced from the LOS mixture has not been encountered in the literature. A simple, easy-to-apply method has been developed for a new adsorbent prepared from a mixture of LOS with environmentally friendly, easy to produce, reusable, cost-effective, non-toxic and with good adsorption-desorption capacity. Therefore, this study will contribute to the world economy in terms of environmental and wastewater cleaning.

摘要

在这项研究中，新的活性炭 (ACs) 由柠檬和橙子 (LOS) 的混合物合成，用于从水溶液中去除有毒金属。吸附剂是通过用不同的活化剂（H ₃ PO ₄、ZnCl ₂和 KOH）和活化温度（600°C、700°C、800°C）。进行元素分析、FT-IR、XRD 和 SEM 分析以确定 AC 的表征。进行了一系列批量吸附实验，研究了各种参数如 pH 值、吸附剂用量、接触时间、温度、络合剂对有毒金属离子（Cu(II)、Cr(III) 和 Ni(II)）的影响。 ) ACs 的去除能力。吸附平衡时间为60 min，Ni(II)离子吸附量为118.02 mg/g，Cr(III)离子吸附量为146.03 mg/g，Cu(II)离子吸附量为150.45 mg/g。_{在 N 2下产生的 AC-ZnCl 2} (600°C)上，在 pH = 5 时观察到有毒金属离子的吸附最大气氛。吸附过程符合Langmuir等温线模型和准二级动力学方程，表明AC上的金属离子吸附是单层覆盖。热力学研究表明吸附本质上是吸热和自发的。文献中没有发现由 LOS 混合物生产的 AC。开发了一种简单、易于应用的方法，用于由 LOS 混合物制备的新型吸附剂，该吸附剂对环境友好、易于生产、可重复使用、成本效益高、无毒且具有良好的吸附-解吸能力。因此，本研究将在环境和废水清洁方面为世界经济做出贡献。