Fabrication of recoverable magnetic composite material based on graphene oxide for fast removal of lead and cadmium ions from aqueous solution

Abstract

BACKGROUND In this study, a novel magnetic material was applied as an adsorbent for simultaneous removal of Pb(II) and Cd(II) ions from aqueous solutions. The adsorbent was synthesized using functionalized MnFe2O4 magnetic nanoparticles grafted to lamellar graphene oxide surface (MnFe2O4@SiO2‐NH2@GO) and characterized using X‐ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis and magnetic measurements. RESULTS The adsorbent exhibited superior adsorption properties for Pb(II) and Cd(II). The maximum uptake capacity of Pb(II) and Cd(II) reached 42.48 and 18.28 mg g−1 within 30 min at 25 °C, respectively. The data for adsorption fitted well with the Langmuir isotherm and pseudo‐second‐order kinetic models, which indicated that the adsorption was via monolayer chemisorption on homogeneous sites. The calculation of thermodynamic parameters revealed spontaneous and endothermic adsorption processes accompanied by randomness increase. X‐ray photoelectron spectroscopy analysis indicated that the coordination between nitrogen atoms of amino groups and the two types of heavy metal ions was a possible adsorption mechanism. CONCLUSIONS MnFe2O4@SiO2‐NH2@GO possesses the properties of high adsorption efficiency, fast separation, high stability and easy regeneration for adsorption of Pb(II) and Cd(II) ions. Thus, the as‐prepared adsorbent is considered as a promising material for the removal of heavy metal ions and this research could offer a new means for water cleanup. © 2020 Society of Chemical Industry

Highly-efficient removal of Pb (II) from water by mesoporous amino functionalized silica aerogels: Experimental, DFT investigations and Life Cycle Assessment

“…After adsorption of Pb (II), the binding energy of -NH 2 and -NH 3 + are remarkably shifted to 400.1 eV and 402.2 eV, respectively (Fig. 11f), which is due to the lone pairs of N coordinate with Pb (II) ions lead to the surrounding electron cloud density decreased and the binding energy increased [74].…”

Resource utilization of oak fruit peel as biomass waste for the synthesis of carbon with graphene oxide-like composition and its composite with Mg1−xCaxFe2O4for Cd(ii) removal from water: characterization, magnetic properties, and potential adsorption study

“…However, these prepared nanocomposites possess a higher removal efficiency at a shorter contact time than those of other nanocomposites reported in the literature, where graphene-structure materials in combination with magnetic ferrites (such as GO/Fe 3 O 4 , MnFe 2 O 4 @SiO 2 -NH 2 @GO) were used as adsorbents. 7,44 This indicated that C GO /MCF nanocomposites could serve as valuable adsorbents for Cd 2+ removal in a short contact time. Therefore, the contact time of 20 min was chosen for the subsequent experimentations.…”

“…Yet, a higher Cd 2+ adsorption capacity was estimated for the studied nanocomposites than grapheneferrite composite materials reported in the literature. 44,46 Adsorption kinetic and isotherm studies…”

Recyclable functionalized polyethyleneimine‐coated magnetic nanoparticles for efficient removal of lead from aqueous solutions

“…The Langmuir model fits better the experimental data, in comparison to the Temkin and Freundlich isotherm models, because of the higher correlation coefficients, suggesting a monolayer adsorption. This indicates that the surfaces are homogeneous and all adsorption sites are equivalent 14,61 . In order to evaluate how suitable the adsorbent is towards the adsorbate investigated, a separation factor constant ( R L ) (Eqn (15)) was applied.…”

“…This indicates that the surfaces are homogeneous and all adsorption sites are equivalent. 14,61 In order to evaluate how suitable the adsorbent is towards the adsorbate investigated, a separation factor constant (R L ) (Eqn ( 15)) was applied. The constant R L (which is dimensionless) enables us to infer if the process of adsorption is favorable or not.…”