Farayandno

Farayandno

Core-shell magnetic nanoparticles Fe3O4@SiO2 functionalized with theophylline molecules as an effective and recyclable nanoadsorbent for the removal of Pb2+ ions from aqueous solutions

Document Type : Original research

Authors
Mohsen Esmaeilpour 1
Majid Ghahraman Afshar 1
Milad Kazemnejadi 2
1 Chemistry and Process Research Department, Niroo Research Institute (NRI), Tehran, Iran
2 Polymer Chemistry Lab, Chemistry Department, Faculty of Sciences, Golestan University, Gorgan, Iran
10.22034/farayandno.2025.2058758.1997
Abstract
In this study, Fe3O4@SiO2 core-shell magnetic nanoparticles were synthesized using coprecipitation and Stöber methods. Afterwards, the obtained nanoparticle is functionalized with organic molecules and finally theophylline. The synthesized nanoparticle was used as an effective adsorbent for the removal of lead ions from aqueous solutions. Then, the structural characteristics, size and morphology of the synthetic nanoadsorbent were determined using analyses such as Fourier transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy, scanning electron microscopy, particle size distribution, nitrogen gas adsorption-desorption, thermogravimetric analysis, X-ray energy dispersive spectroscopy and vibrating sample magnetometer. The effective parameters in the nanoadsorbent adsorption process are evaluated by investigating of contact time, pH, initial concentration of Pb2+ ions and adsorbent dosage. The results indicate that the maximum Pb2+ adsorption capacity of 130.5 mg/g occurs when 25 mg of Fe3O4@SiO2-TCT-Theophylline nanoadsorbent, 50 mL of Pb2+ solution, initial concentration mmol/L0.35, at pH=7 and a contact time of 24 min. In addition, the synthetic nanoadsorbent has the ability to be recycled and reused in sequential adsorption-desorption processes for 6 times without serious reduction in adsorption activity.
Keywords
Fe3O4@SiO2 Nanoparticles
Theophylline
Magnetic Adsorbent
Effective Adsorption
Lead Ion
Sequential Adsorption-Desorption

Subjects

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