Pb(II) Adsorption Onto a Magnetic Composite of Activated Carbon and Superparamagnetic Fe₃O₄ Nanoparticles: Experimental and Modeling Study

Abstract

Magnetic separation technology has been extensively used in the field of environmental problems, due to solving difficulties resulted from filtration and centrifuging. In this study, powder activated carbon (PAC) was magnetized by magnetite nanoparticles (Fe3O4@C) as an adsorbent for lead ions (Pb2+) from aqueous solution. The characteristics of the modified PAC were analyzed by scanning electron microscopy, transmission electron microscopy, X‐ray diffractometry, Brunauer‐Emmett‐Teller surface area analysis, energy dispersive X‐ray spectroscopy, and vibrating sample magnetometry. Batch adsorption experiments were conducted as a function of pH, contact time, adsorbent dosage and initial Pb2+ concentration, and solution temperature. The equilibrium isotherm and kinetic models were used to evaluate the fitness of the experimental data. The maximum mono‐layer adsorption capacity of Pb2+ was 71.42 mg/g at 50°C. It could also be shown that the sorption isotherms were well described by the Langmuir equilibrium model. The kinetic of the adsorption process was found to follow the pseudo‐second‐order model expression. Thermodynamic studies indicated that the adsorption process was feasible, spontaneous, and endothermic. Desorption experiments exhibited that the Fe3O4@C had a good potential in regard to regeneration and reusability and is easily regenerated by HCl solution. The proposed adsorption process can be a promising technique for Pb2+ removal from aqueous solutions and to be used in full‐scale and industrial applications.

Hexavalent chromium adsorption from aqueous solutions using nanoporous graphene/Fe3O4(NPG/Fe3O4: modeling and optimization)

“…According to the regression coefficient (R 2 ), the adsorption kinetics can be better explained by the pseudo-second-order model. Similar results were also reported by the other researchers that shown pseudo-second-order model fitted better the experimental data [39].…”

Application of Fe3O4@C catalyzing heterogeneous UV-Fenton system for tetracycline removal with a focus on optimization by a response surface method

“…This could be due to the formation of Fe3O4 inside of the PAC pores. Similar observation has been reported in the literature [27][28][29]. This result also implies that after the reaction there were no remarkable changes in the magnetic properties of Fe3O4@C. Thus, the catalyst could be used for several times with only a slight loss of saturation magnetization.…”

Bioremediation of Cu(II) contaminated water by Saccharum officinarum: effect of oxalic acid modification on equilibrium, kinetic and thermodynamic parameters

“…As shown in the figure, as the quantity of the biosorbent increased from 0.1 to 0.2 g the % Cu 2+ ion removed increases from 64 to 79 % for RAWB while the increase is from 80 to 97 % for OAMB. Upon increasing the biosorbent dosage, an increase in the percentage removal was noted which climaxed at biosorbent dosage of 0.2 g. Increased Cu 2+ removal with increasing biosorbent dosage is attributed to the increase of total adsorbent surface area and adsorption sites, while the subsequent reduction in the percentage removal at biosorbent dosage above 0.2 g may be attributed to to the particle interactions, such as aggregation, resulting from high adsorbent concentrations which lead to a reduction of the active surface area of the biosorbent (Kakavandi et al 2015).…”