EDTA-functionalized magnetic chitosan oligosaccharide and carboxymethyl cellulose nanocomposite: Synthesis,...

A novel ethylenediaminetetraacetic acid (EDTA)-functionalized magnetic chitosan oligosaccharide and carboxymethyl cellulose (Fe₃O₄@CMCCOS-EDTA) nanocomposite adsorbent was successfully fabricated for Pb(II) adsorption. The adsorbent was characterized by Fourier transform infrared, and X-ray photoelectron spectroscopy was used to confirm successful EDTA modification and Pb(II) adsorption. Scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometer, and thermogravimetric analysis were used to study the morphology and properties of magnetic particles. EDTA modification considerably improved the capacity of the adsorbent. The batch adsorption experiment results indicated that the pseudo-second-order (PSO) model and the Langmuir isotherm model reliably described the adsorption behavior. The maximum adsorption capacity (q_m) for monolayer chemical adsorption was calculated to be 432.34 mg/g at the pH of 5 and temperature of 308 K. Notably, Fe₃O₄@CMCCOS-EDTA exhibited a high Pb(II) removal rate of ~100% using an initial metal ion solution of 100 mg/L and 200 mg/L.