Ahmad Rabia, Alzahrani Elham A, Dwivedi Poonam, Hafeez Sumbul, Deswal Jyoti, Fatima Bushra, Siddiqui Sharf Ilahi, Oh Seungdae
Department of Chemistry, Jamia Millia Islamia, New Delhi 110025, India.
Department of Chemistry, College of Science, University of Ha'il, Ha'il 81451, Saudi Arabia.
Molecules. 2024 Aug 15;29(16):3867. doi: 10.3390/molecules29163867.
This study demonstrated the synthesis of FeMnO modified by citric acid, a biodegradable acid, using a simple co-precipitation method. Characterization was performed using qualitative analysis techniques such as Fourier-transformed infrared spectroscopy, scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy, X-ray diffraction, selected-area electron diffraction, N adsorption-desorption, and zero-point charge. The prepared nanoparticles had a rough and porous surface, and contained oxygenous (-OH, -COOH, etc.) functional groups. The specific surface area and average pore size distribution were 83 m/g and 5.17 nm, respectively. Net zero charge on the surface of the prepared nanoparticles was observed at pH 7.5. The prepared nanoparticles were used as an adsorbent to remove methylene blue dye from water under various conditions. Using small amounts of the adsorbent (2.0 g/L), even a high concentration of MB dye (60 mg/L) could be reduced by about ~58%. Exothermic, spontaneous, feasible, and monolayer adsorption was identified based on thermodynamics and isotherm analysis. Reusability testing verified the stability of the adsorbent and found that the reused adsorbent performed well for up to three thermal cycles. Comparative analysis revealed that the modified adsorbent outperformed previously reported adsorbents and unmodified FeMnO in terms of its partition coefficient and equilibrium adsorption capacity under different experimental conditions.
本研究展示了采用简单的共沉淀法合成由可生物降解的柠檬酸改性的FeMnO。使用傅里叶变换红外光谱、配备能量色散X射线光谱的扫描电子显微镜、X射线衍射、选区电子衍射、N吸附-脱附以及零电荷点等定性分析技术进行表征。所制备的纳米颗粒具有粗糙且多孔的表面，并含有含氧（-OH、-COOH等）官能团。比表面积和平均孔径分布分别为83 m/g和5.17 nm。在所制备的纳米颗粒表面，在pH 7.5时观察到净零电荷。所制备的纳米颗粒用作吸附剂，在各种条件下去除水中的亚甲基蓝染料。使用少量吸附剂（2.0 g/L），即使是高浓度的MB染料（60 mg/L）也可降低约58%。基于热力学和等温线分析确定为放热、自发、可行且为单层吸附。可重复使用性测试验证了吸附剂的稳定性，发现重复使用的吸附剂在多达三个热循环中表现良好。对比分析表明，在不同实验条件下，改性吸附剂在分配系数和平衡吸附容量方面优于先前报道的吸附剂和未改性的FeMnO。
