Rekaby M, Abou-Aly A I, El-Khatib M
Department of Physics, Faculty of Science, Alexandria University, Alexandria, Egypt.
Department of basic sciences, Faculty of Computer Science and Artificial Intelligence, Pharos University, Alexandria, Egypt.
Sci Rep. 2023 Oct 21;13(1):18006. doi: 10.1038/s41598-023-45136-w.
Herein, the adsorption of methyl orange (MO), a dangerous anionic dye, from an aqueous solution was investigated using a novel magnetic nanocomposite adsorbent. A nanocomposite entitled manganese chromium-layered double oxide/cobalt spinel ferrite, (MnCr)-LDO/CoFeO, which links the interlayer structural characteristics of layered double oxides (LDOs) with the magnetic properties of spinel ferrites (SFs) was synthesized using the eco-friendly co-precipitation technique. Determination of structural parameters, crystallite size, and micro-strain was done using X-ray diffraction (XRD) analysis. Transmission electron microscopy (TEM) was used to determine grain shape and size. Surface analysis was performed using X-ray photoelectron spectroscopy (XPS) to identify elements and oxidation states present in the prepared nanocomposite. Vibrating sample magnetometer (VSM) was utilized to examine the magnetic characteristic. A comprehensive comparative study about the effectiveness and durability of CoFeO and (MnCr)/CoFeO as nanoadsorbents for MO was conducted. Numerous variables, including contact time, MO concentration, adsorbent dosage, and pH were tested for their effects on the adsorption removal percentages. The findings showed that the maximum removal percentage was 86.1% for 25 ppm of MO was for 0.1 g/100 mL of (MnCr)-LDO/CoFeO at pH = 3. Investigations of isotherms and kinetics were conducted under batch conditions. The Langmuir isotherm matched the experimental data, for both nanoadsorbents, quite well due to the homogeneous distribution of active sites. Adsorption kinetics data were found to be compatible with intra-particle diffusion and pseudo-second order models for CoFeO and (MnCr)/CoFeO, respectively. A total of five adsorption-desorption cycles were performed to determine the prepared adsorbents' recyclable nature.
本文采用一种新型磁性纳米复合吸附剂，研究了从水溶液中吸附危险阴离子染料甲基橙（MO）的情况。合成了一种名为锰铬层状双氧化物/钴尖晶石铁氧体的纳米复合材料，即(MnCr)-LDO/CoFeO，它将层状双氧化物（LDOs）的层间结构特征与尖晶石铁氧体（SFs）的磁性联系起来，采用了环保的共沉淀技术。使用X射线衍射（XRD）分析来确定结构参数、微晶尺寸和微应变。透射电子显微镜（TEM）用于确定颗粒形状和尺寸。使用X射线光电子能谱（XPS）进行表面分析，以识别制备的纳米复合材料中存在的元素和氧化态。利用振动样品磁强计（VSM）检测磁性特征。对CoFeO和(MnCr)/CoFeO作为MO纳米吸附剂的有效性和耐久性进行了全面的比较研究。测试了包括接触时间、MO浓度、吸附剂用量和pH值在内的众多变量对吸附去除率的影响。结果表明，对于25 ppm的MO，在pH = 3时，0.1 g/100 mL的(MnCr)-LDO/CoFeO的最大去除率为86.1%。在间歇条件下进行了等温线和动力学研究。由于活性位点的均匀分布，Langmuir等温线与两种纳米吸附剂的实验数据都非常吻合。发现吸附动力学数据分别与CoFeO的颗粒内扩散模型和(MnCr)/CoFeO的准二级模型相符。总共进行了五个吸附-解吸循环，以确定制备的吸附剂的可回收性质。
