FeNi3@SiO2@CuS magnetic nanocomposite: synthesizing, characterization, and application for methylene blue adsorption

• Published in: Desalination and water treatment 2021-01, Vol.210, p.402-414
• Main Authors: Nasseh, Negin, Al-Musawi, Tariq J., Khosravi, Rasoul, Panahi, Ayat Hossein, Arghavan, Fatemeh Sadat, Barikbin, Behnam
• Format: Article
• Language: English
• Subjects: Adsorption; Characterization; FeNi3@SiO2@CuS; Magnetic nanocomposite; Methylene blue
• ISSN: 1944-3986; 1944-3986
• DOI: 10.5004/dwt.2021.26456

A novel magnetic nanocomposite adsorbent formed from the coating FeNi3 nanoparticles with SiO2 nanoparticles, and then with CuS nanoparticles (FeNi3@SiO2@CuS) was successfully synthesized and then applied, for the first time, for eradicating methylene blue (MB) dye-laden waste-water. An adsorptive performance test were conducted using a batch system with variations of several water quality parameters, including pH, contact time, MB concentration, FeNi3@SiO2@CuS dose, and competitor NaCl concentration. The characterization study using transmission electron microscopy, field emission scanning electron microscopy, and vibrating sample magnetometer approaches demonstrated that FeNi3@SiO2@CuS has a number of favorable morphological, physiochemical, and adsorptive properties which make it a potential adsorbent toward organic pollutants. The equilibrium analysis of non-linear fit method revealed that the Langmuir equation was the best model for the representation of isothermal data, where the maximum uptake reached 24.457 mg/g. The kinetic adsorption behavior of methylene blue on FeNi3@SiO2@CuS obeyed the pseudo-second-order kinetics. The nature of the adsorption was also endothermic and spontaneous, as the thermodynamic study revealed. During the adsorption experiments, FeNi3@SiO2@CuS magnetic nanocomposite exhibited an excellent adsorption capacity toward MB molecules, where the maximum removal efficiency of 85.21% was recorded at pH = 12, contact time = 180 min, initial MB concentration = 20 mg/L, and FeNi3@SiO2@CuS dose = 2 g/L. It was also found that NaCl presence had a negative impact on that efficiency. The mechanism of MB interaction with FeNi3@SiO2@ CuS involved both chemical and physical adsorption processes. Results of this study unraveled that the adsorption process using FeNi3@SiO2@CuS as an adsorptive agent could be a promising treatment technology for the removal of MB dye from high alkaline wastewater.