Civan Çavuşoğlu Ferda, Özçelik Gülsüm, Bayazit Şahika Sena
Department of Chemical Engineering, Faculty of Engineering and Architecture, İstanbul Beykent University, İstanbul, Turkiye.
Department of Nanotechnology, Nanotechnology and Biotechnology Institute, İstanbul University-Cerrahpaşa, İstanbul, Turkiye.
Turk J Chem. 2023 Sep 30;47(6):1479-1496. doi: 10.55730/1300-0527.3629. eCollection 2023.
Cr(VI), which has toxic effects, is a heavy metal and it must be removed from the environment due to the various damages it causes. In this study, the removal of Cr(VI) pollutants from aqueous solutions with FeO-based materials using a batch adsorption technique was investigated. Magnetically modified graphene nanoplatelet (GNP)-based nanocomposites were prepared and their structures were characterized by FTIR, XRD, SEM, BET, and TGA techniques. The effects of various physicochemical parameters such as adsorbent dose, contact time, initial Cr(VI) solution concentration, pH, and the presence of coexisting ions (NaCl) on the adsorption process were investigated. Accordingly, the optimum conditions for Cr(VI) removal were determined. Nonlinear Langmuir, Freundlich, and Temkin isotherm models and pseudo-first-order, pseudo-second-order, and Bangham kinetic models were used to investigate the adsorption mechanism. The experimental data relatively fit the second-order kinetic model and the Freundlich isotherm model. The maximum adsorption capacities for pure FeO (Fe:GNP 1:0), Fe:GNP (2:1), and Fe:GNP (1:1) nanocomposite materials at 298 K and pH of approximately 5 were obtained as 12.71 mg/g, 27.03 mg/g, and 62.27 mg/g, respectively. This result showed that Cr(VI) removal increased as the amount of GNP in the composite material increased. Generally, the results confirmed that magnetically modified GNP-based adsorbents are functional and promising materials that can be used for the removal of pollutants such as Cr(VI) from aqueous media.
具有毒性作用的六价铬是一种重金属，由于其造成的各种损害，必须将其从环境中去除。在本研究中，采用间歇吸附技术研究了用铁氧化物基材料从水溶液中去除六价铬污染物的情况。制备了磁性修饰的基于石墨烯纳米片（GNP）的纳米复合材料，并通过傅里叶变换红外光谱（FTIR）、X射线衍射（XRD）、扫描电子显微镜（SEM）、比表面积分析仪（BET）和热重分析（TGA）技术对其结构进行了表征。研究了吸附剂用量、接触时间、初始六价铬溶液浓度、pH值以及共存离子（氯化钠）的存在等各种物理化学参数对吸附过程的影响。据此，确定了去除六价铬的最佳条件。采用非线性朗缪尔等温线模型、弗伦德里希等温线模型和坦金等温线模型以及准一级动力学模型、准二级动力学模型和班汉姆动力学模型来研究吸附机理。实验数据相对符合二级动力学模型和弗伦德里希等温线模型。在298K和约5的pH值条件下，纯FeO（铁：GNP 1:0）、铁：GNP（2:1）和铁：GNP（1:1）纳米复合材料的最大吸附容量分别为12.71mg/g、27.03mg/g和62.27mg/g。该结果表明，随着复合材料中GNP含量的增加，六价铬的去除率提高。总体而言，结果证实磁性修饰的基于GNP的吸附剂是功能性且有前景的材料，可用于从水介质中去除六价铬等污染物。
