Ca-alginate/carboxymethyl chitosan/Ni0.2Zn0.2Fe2.6O4 magnetic bionanocomposite: Synthesis, characterization and application for single adsorption of Nd+3, Tb+3, and Dy+3 rare earth elements from aqueous media

Abstract

This study aims to research the adsorption of Nd+3, Tb+3, and Dy+3 from aqueous media onto the magnetic calcium alginate/carboxymethyl chitosan/Ni0.2Zn0.2Fe2.6O4 (CA/CMC/Ni0.2Zn0.2Fe2.6O4) bionanocomposite in a single system. FE-SEM, FT-IR, EDX, VSM, and TGA were applied to characterize the product. The VSM result showed the saturation magnetization values of 45.87 and 14.14 emu/g for the bare Ni0.2Zn0.2Fe2.6O4 nanoparticles and CA/CMC/Ni0.2Zn0.2Fe2.6O4, respectively. The adsorption results showed that at optimum conditions of contact time of 40 min, pH of 5.5, and 0.8 g/L, the adsorption efficiency of the adsorbent for Nd+3, Tb+3, and Dy+3 was 97.75, 96.83, and 97.85%, respectively. The ions adsorption kinetic onto the CA/CMC/Ni0.2Zn0.2Fe2.6O4 was in accordance with pseudo-second-order (PSO) model. The evaluation of equilibrium data was performed by the isotherm models of Langmuir and Freundlich. Fitting the experimental data of Tb+3 and Dy+3 was done better with Freunlich model than Langmuir model, while fitting tests for Nd+3 adsorption data showed better coverage using Langmuir model with a maximum adsorption capacity of 73.37 mg/g. The results of the parameters of thermodynamic showed the endothermic and spontaneous properties of the process. Additionally, the efficacy of the adsorbent was studied using 0.2 M HNO3 in four adsorptions–desorption cycles. Overall, the obtained results demonstrated that the environmentally friendly magnetic bionanocomposite adsorbent can be applied effectively for Nd+3, Tb+3, and Dy+3 adsorption with favorable adsorption efficiency.