Adsorption of Sr(II) ions and salicylic acid onto magnetic magnesium-zinc ferrites: isotherms and kinetic studies

Abstract

Magnetic magnesium-zinc spinel ferrite Mg 1 − x Zn x Fe 2 O 4 (where x = 0.4, 0.6, and 0.8) was investigated as adsorbent for the efficient removal of Sr(II) ions and salicylic acid (SA) contaminants from aqueous medium. The characterization of ferrites was carried out using XRD, VSM, BET, SEM, and EDS. The surface charge of magnetic adsorbents was measured by the drift method. The determination of SA and Sr(II) ion concentrations in the solution phase was carried out by UFLC and complexometry, respectively. It was shown that varying of the Zn(II) content affected the adsorption capacities of magnesiumzinc ferrites. The increasing of zinc content from x(Zn 2+) = 0.4 to x(Zn 2+) = 0.6 increased the adsorption of Sr(II) ions from 50 to 65 mg/g, and then it was decreased to 36 mg/g for the sample with x(Zn) = 0.8. The Mg 0.4 Zn 0.6 Fe 2 O 4 sample demonstrated the maximum adsorption capacity of 74 mg/g. The adsorption isotherm for Sr(II) was fitted by the Dubinin-Radushkevich, Langmuir, Freundlich, and Sips models. The adsorption kinetics of Sr(II) was analyzed by PFO, PSO, and Elovich models. The adsorption kinetics of SA was also investigated. It was demonstrated that the Mg 0.2 Zn 0.8 Fe 2 O 4 sample exhibited 90% removal of salicylic acid from the water solutions. The results demonstrated that magnetic Mg-Zn ferrites with spinel structure are good sorbents for the removal of SA and Sr(II) ions from aqueous solution.

Green Synthesis of Metal and Metal Oxide Nanoparticles: Principles of Green Chemistry and Raw Materials

“…Spinel ferrites with the general formula AB 2 O 4 have great chemical, catalytic, adsorption and magnetic properties [143][144][145][146][147][148]. Spinel ferrites have attracted much attention due to their thermal and chemical resistance [149][150][151][152][153][154].…”

Structural, Optical and Magnetic Properties of Diamagnetic Cd2+ Incorporated Cobalt Ferrite Thin Films Deposited by Spray Pyrolysis

“…63 The intrinsic stretching vibration bands of the metal were mostly detected at the tetrahedral site at 600-550 cm −1 and the octahedral widening site at 450-385 cm −1 . [64][65][66] Generally, in spinel ferrites the bond length of the metal-oxygen at tetrahedral site is significantly shorter than that of the octahedral site and thus the higher stretching frequency for the M-O bond at tetrahedral site. 67,68 However, in the current circumstance only a unique major band near 600 cm −1 was observed as the FTIR spectra were documented in the range of 500-4000 cm −1 .…”

Adsorptive removal of pollutants from water using magnesium ferrite nanoadsorbent: a promising future material for water purification

“…However, the concentrations of pharmaceuticals in water are usually very low, which make removal of them much difficult (Khan et al 2021a). Magnesium ferrite nanomaterials have been used to remove salicylic acid (a derivative of different medicine), minocycline (a tetracycline antibiotic) and ibuprofen from water through adsorption process (Lu et al 2016;Ivanets et al 2020;Tatarchuk et al 2020b).…”