Iron (III) and iminodiacetic acid functionalized magnetic peanut husk for the removal of phosphate from solution: Characterization, kinetic and equilibrium studies

PN-Fe3O4-IDA-Fe formed by the chemical modification of peanut husk with Fe3O4 and iminodiacetic acid (IDA) and subsequently loaded with Fe3+ ions was applied for the removal of phosphate from aqueous solution. Analytical techniques such as the Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and the vibrating sample magnetometer (VSM) were used to determine the nature of this novel adsorbent. Adsorption studies involving the use of PN-Fe3O4-IDA-Fe for the removal of phosphate showed that the Freundlich isotherm model was best to fit the experimental data with the maximum adsorption capacity observed to be 33.7 mg g(-1) (as P) at 303 K. The kinetic adsorption process was observed to be best described by the pseudo-second-order kinetic model. This novel adsorbent with good adsorption capacity possesses advantages of green synthesis, low-cost, easy separation from solution and the property of reuse after regeneration. (C) 2020 Elsevier Ltd. All rights reserved.