Capabilities of nickel zinc ferrite and its nanocomposite with CNT for adsorption of arsenic (V) ions from wastewater

Abstract

Ni0.5Zn0.5Fe2O4 Ferrite (NZF) and Ni0.5Zn0.5Fe2O4/CNTs nanocomposite (CNZF) were prepared by inverse co-precipitation method as novel magnetic adsorbents. The characteristic consequences of XRD, FTIR, FESEM and XPS analysis indicated that the adsorbents were favorably produced. The results revealed that the saturated magnetization (Ms) of the NZF and CNZF powders was 35 and 15 emu/g, respectively. The reason of this decrease for the CNZF nanocomposite was the existence of CNT with a weak magnetic property in the complex of CNZF compared to the NZF. However, the both adsorbents have a fast-magnetic response that can be effective for separation of adsorbents from the solution by an external magnetic field. The adsorbents were then assessed for removal of arsenic(V) contaminated anions from simulated industrial wastewater. Batch reactor model was utilized to investigate the performance of adsorption and modifying efficient parameters like pH, adsorbent dosage and contact time to enhance the maximum adsorption capacity (qm). The maximum adsorption capacities of NZF and CNZF were found to be 56 mg/g and 66 mg/g, respectively at contact time of 30 min, adsorbent dosage of 6 g/l and pH of 2. The adsorption isotherm as a function of adsorbent dosage was assessed. It was shown that Langmuir isotherm had the highest consistency with the experimental data for both adsorbents. The kinetic behavior of adsorption over the time was evaluated. The pseudo-second order model provided the finest agreement to the experimental data. The dominant mechanism of adsorption was estimated to be surface complexation.