Adsorption of Cu(II), Pb(II), and Cd(II) Ions from Acidic Aqueous Solutions by Diethylenetriaminepentaacetic Acid-Modified Magnetic Graphene Oxide

Abstract

In this study, diethylenetriaminepentaacetic acid (DTPA)-modified magnetic graphene oxide (MGO) was synthesized for removal of Cu­(II), Pb­(II), and Cd­(II) ions from acidic aqueous solutions. The prepared DTPA/MGO composites were characterized by scanning electron microscopy, X-ray diffraction, Fourier transform infrared and X-ray photoelectron spectroscopies, and zeta potential. The results showed that DTPA successfully functionalized MGO. Adsorption experiments indicated that DTPA/MGO composites exhibited excellent adsorption property in acidic aqueous solutions. The adsorption processes were applicable for the Langmuir adsorption isotherm and the pseudo-second-order model. The maximum adsorption capacities at pH 3.0 for Cu­(II), Pb­(II), and Cd­(II) ions were 131.4, 387.6, and 286.5 mg/g, respectively. The thermodynamic studies demonstrated that adsorption processes were endothermic and spontaneous. Moreover, the DTPA/MGO composites could selectively adsorb Pb­(II) from multimetal mixed systems. Adsorption–desorption results showed that the DTPA/MGO composites exhibited excellent reusability. These results suggested that DTPA/MGO composites have great potential in removing heavy metals from acidic wastewater, especially for Pb­(II).

Diverse Surface Chemistry of Cobalt Ferrite Nanoparticles to Optimize Copper(II) Removal from Aqueous Media

“…The metal uptake capacities of the samples revealed that MNPs@ODA@PEI (164.2 mg/g) exhibited a superior sorption efficiency compared to MNPs@ODA@DTPA (29.4 mg/g) and MNPs@ODA@PEI@DTPA (40.4 mg/g). This value can be considered among the best of those previously reported for nanoabsorbents [25,31,54], while can be attributed to the polymeric branched nature of PEI and the greater amount of amino groups that were present. Even though the surface of the PEI-modified particles was strongly positive charged (+42.9 mV), suggesting that amino groups were protonated to -NH + 3 , a sufficient percentage of -NH 2 was available.…”

Recent Advances in Applications of Hybrid Graphene Materials for Metals Removal from Wastewater

“…Najafabadi et al used glyoxal as a crosslinking agent to develop chitosan/graphene oxide using electrospinning [38]. Li et al cross-linked DTPA and mGO using diethylenetriamine to produce (DTPA/MGO) [39]. Zare-Dorabei et al modified graphene oxide with 2,20-dipyridylamine to make (GO-DPA) for the Zhu et al used ZnSO 4 •7H 2 O to create GO/Brianyoungite GO/BY) composite with hollow spherical and flake-like morphologies.…”

Reactive Extraction of Lactic Acid using Environmentally Benign Green Solvents and Synergistic Mixture of Extractants

“…The industrial and traditional technique of LA separation is precipitation, which uses calcium hydroxide and large amounts of sulfuric acid and further produces solid waste, i.e., calcium sulfate (environmentally unfriendly) as a by-product [8,9]. In order to reduce the cost, various extraction methods (such as adsorption [10], membrane separation [11,12], electrodialysis [13,14], ultra ltration [15], and extraction [16,17]) have e caciously been applied to the extraction of LA. All these methods possess several speci c disadvantages (such as poor extraction e ciency (%), being uneconomical, the generation of huge amount of wastewater, high complexity, high energy consumption, and large production of by-products) [13].…”