Chemistry Department, Faculty of Science (Boys Campus), Al-Azhar University, Cairo, Egypt.
Main Defense Chemical Laboratories (M.D.C.L), Almaza, Cairo, Egypt.
Sci Rep. 2023 Mar 14;13(1):4209. doi: 10.1038/s41598-023-28556-6.
The present study reports the feasibility of the synthesis of a novel porous composite adsorbent, prepared from olive stone activated carbon (OS400) and garnet (GA) mineral impregnations (referred to as OSMG). This composite (OSMG) was applied for its ability to adsorb a macromolecular organic dye. The composite's structural characteristics were evaluated using various techniques such as Brunauer-Emmett-Teller (BET), Scanning Electron Microscopy equipped with Energy Dispersive X-ray spectroscopy (SEM-EDX), X-ray diffraction (XRD), and a Fourier transform infrared spectrometer (FT-IR). The specific surface area of the garnet (GA), (OS400), and (OSMG) were found to be 5.157 mg⋅g, 1489.598 mg⋅g, and 546.392 mg⋅g, respectively. The specific surface area of the new composite (OSMG) was promoted to enhance the adsorption of methylene blue (MB). Experiments were conducted under various conditions, including contact time, initial dye concentration, adsorbent dosage, pH, and temperatures. Data from these experiments were analyzed using several adsorption models including Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich (D-R). The results indicated that, the adsorption fit best with the Freundlich model and that the adsorption process followed a pseudo-second-order kinetic mechanism. Additionally, the thermodynamic analysis indicated the adsorption of MB onto garnet(GA) adsorbents is endothermic, while the sorption onto (OS400) and (OSMG) is an exothermic and non-spontaneous process. The OSMG composite can be used for at least five cycles without significant loss of adsorptive performance, and can easily be separated from the water after treatment.
本研究报告了一种新型多孔复合吸附剂的合成可行性，该吸附剂由橄榄石活性炭（OS400）和石榴石（GA）矿物浸渍制备（称为 OSMG）。该复合材料（OSMG）被应用于其吸附高分子有机染料的能力。通过使用各种技术，如 Brunauer-Emmett-Teller（BET）、带有能量色散 X 射线光谱的扫描电子显微镜（SEM-EDX）、X 射线衍射（XRD）和傅里叶变换红外光谱仪（FT-IR）来评估复合的结构特征。发现石榴石（GA）、（OS400）和（OSMG）的比表面积分别为 5.157 mg⋅g、1489.598 mg⋅g 和 546.392 mg⋅g。新复合（OSMG）的比表面积得到了提升，以增强对亚甲基蓝（MB）的吸附。实验在不同条件下进行，包括接触时间、初始染料浓度、吸附剂用量、pH 值和温度。使用几种吸附模型（包括 Langmuir、Freundlich、Temkin 和 Dubinin-Radushkevich（D-R））对这些实验数据进行了分析。结果表明，吸附最符合 Freundlich 模型，吸附过程遵循准二级动力学机制。此外，热力学分析表明，MB 吸附到石榴石（GA）吸附剂上是吸热的，而吸附到（OS400）和（OSMG）上是放热和非自发的过程。OSMG 复合材料在至少五个循环中可以保持良好的吸附性能，并且在处理后可以很容易地从水中分离出来。
