Studying the physicochemical characteristics and metals adsorptive behavior of CMC-g-HAp/Fe3O4 nanobiocomposite

• Published in: Journal of environmental chemical engineering Vol. 6; no. 5; pp. 6049 - 6058
• Main Authors: Foroutan, Rauf, Ahmadlouydarab, Majid, Ramavandi, Bahman, Mohammadi, Reza
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-10-2018
• Subjects: Adsorption; Carboxymethyl cellulose; Hydroxyapatite; Nanobiocomposite; Thermodynamic study; Carboxymethyl cellulose; Hydroxyapatite; Nanobiocomposite; Adsorption; Thermodynamic study
• ISSN: 2213-3437; 2213-3437
• DOI: 10.1016/j.jece.2018.09.030

A schematic of CMC-g-HAP/Fe3O4 production process.
[Display omitted]
•CMC-g-HAp/Fe3O4 was designed for adsorption of heavy metals from aqueous solutions.•Hydroxyl, carboxylic, and phosphate were functional groups in the adsorbent structure.•Langmuir isotherm well-described data (qm = 88.49 g Cu/g and 86.95 mg Ni/g).•Adsorption data was obeyed the second-order kinetic model (R2 >0.99).•The specific saturation magnetization of the adsorbent was obtained as 28.73 emu/g.
In current study, the capabilities of CMC-g-HAp/Fe3O4 nanocomposite as an adsorbent for sorption of heavy metal ions of copper and nickel from aqueous is reported. Nanocomposite properties were characterized by FTIR, SEM, EDAX, map, TEM, XRD, TGA, VSM, and AFM techniques. According to FTIR test, the main functional groups involved in the sorption of metals were of OH, CH, CO, PO43−, and Fe-O. The specific saturation magnetization (σs) for CMC-g-HAp/Fe3O4 nanobiocomposite was determined as 28.73 emu/g. Besides, our results show that the kinetic behavior of the copper and nickel ion adsorption process using nanobiocomposite CMC-g-HAp/Fe3O4 obeys the pseudo-second-order kinetic model. Additionally, the equilibrium state of the adsorption process was studied using Langmuir, Freundlich, and Dobbin-Radskovich (D-R) isotherm models. The maximum sorption capacity of CMC-g-HAp/Fe3O4 nanocomposites for copper and nickel ions was obtained 88.49 mg/g and 86.95 mg/g, respectively. Moreover, the average free energy (E) for the copper and nickel ion adsorption processes were attained 1.63 kJ/moL and 1.25 kJ/mol, respectively. This E value shows that the adsorption process of both metal ions using the CMC-g-HAp/Fe3O4 nanobiocomposite is physical. Finally, enthalpy (ΔHᵒ), entropy (ΔSᵒ), and Gibbs free energy (ΔGᵒ) were calculated for the thermodynamic behavior of the process. The outcomes indicated that the copper and nickel ions adsorption process using CMC-g-HAp/Fe3O4 nanobiocomposite is exothermic and spontaneous.