Removal of Lead from Wastewater Using Synthesized Polyethyleneimine-Grafted Graphene Oxide

Abstract

In this work, polyethyleneimine-grafted graphene oxide (PEI/GO) is synthesized using graphene, polyethyleneimine, and trimesoyl chloride. Both graphene oxide and PEI/GO are characterized by a Fourier-transform infrared (FTIR) spectrometer, a scanning electron microscope (SEM), and energy-dispersive X-ray (EDX) spectroscopy. Characterization results confirm that polyethyleneimine is uniformly grafted on the graphene oxide nanosheets and, thus, also confirm the successful synthesis of PEI/GO. PEI/GO adsorbent is then evaluated for the removal of lead (Pb2+) from aqueous solutions, and the optimum adsorption is attained at pH 6, contact time of 120 min, and PEI/GO dose of 0.1 g. While chemosorption is dominating at low Pb2+ concentrations, physisorption is dominating at high concentrations and the adsorption rate is controlled by the boundary-layer diffusion step. In addition, the isotherm study confirms the strong interaction between Pb2+ ions and PEI/GO and reveals that the adsorption process obeys well the Freundlich isotherm model (R2 = 0.9932) and the maximum adsorption capacity (qm) is 64.94 mg/g, which is quite high compared to some of the reported adsorbents. Furthermore, the thermodynamic study confirms the spontaneity (negative ΔG° and positive ΔS°) and the endothermic nature (ΔH° = 19.73 kJ/mol) of the adsorption process. The prepared adsorbent (PEI/GO) offers a potential promise for wastewater treatment because of its fast and high uptake removal capacity and could be used as an effective adsorbent for the removal of Pb2+-ions and other heavy metals from industrial wastewater.

Recent Progress on the Adsorption of Heavy Metal Ions Pb(II) and Cu(II) from Wastewater

“…The adsorption capacity of Pb(II) by RGO/PAM is up to 1000 mg/g. Mohammed et al [ 69 ] synthesized polyvinylimide grafted graphene oxide (PEI/GO). The maximum adsorption capacity (q m ) is 64.94 mg/g.…”

Application of a three dimensional polyethyleneimine functionalized graphene oxide aerogel as an adsorbent for the determination of phytohormones in ginseng

“…23 Functionalized GO thus provides additional adsorption sites, enhancing the adsorption capacity of the adsorbents to some extent. Previous research has documented the potential of combining PEI-GO with diverse substrates to produce a wide range of composite materials, such as hybrid nanomaterials, magnetic nanomaterials, hydrogels, and aerogels, to adsorb herbicides, 24 Cr, 25 Hg, 26 Cu, 27 Pb, 28 dyes and organic solvents. 29 Despite the existence of various PEI-GO-based materials in the literature, their usage has been limited to the adsorption of hazardous pollutants.…”

Removal of Diclofenac and Heavy Metal Ions from Aqueous Media Using Composite Sorbents in Dynamic Conditions

“…Another strong advantage of this process is the availability of a wide range of sorbents and the possibility of regeneration and reusability of the used sorbents. Several sorbent materials, including activated carbon [ 14 , 15 ], composites with activated carbon [ 16 ], zeolites [ 17 , 18 ], biochar [ 19 ], biosorbents [ 20 , 21 ], chitosan [ 22 , 23 ], clays [ 24 ], metal–organic frameworks [ 25 , 26 ], activated hydrochars [ 27 ], carbon nanotubes [ 28 ], graphenes [ 29 , 30 ], polymers [ 8 , 31 ] and nano-adsorbents [ 32 , 33 , 34 ], have been investigated for the removal of different organic/inorganic priority and emerging pollutants. Among them, composite sorbents may represent the best choice to deal with toxic pollutants such as pharmaceuticals and heavy metal ions.…”