Co-precipitation synthesis of Mg-Al-CO3 layered double hydroxides and its adsorption kinetics with phosphate(V) ions

Phosphorus (P) is an essential mineral nutrient in crop production. Phosphorus runoff and leaching from agricultural lands leads to eutrophication, causing hypoxia and anoxia in bodies of water. Mitigation of this problem through P removal is essential to prevent detrimental damages to the environment. In this work, Mg-Al-CO3 layered double hydroxides (LDH) were synthesized via co-precipitation method and its capacity as a potential phosphate(V) adsorbent was investigated. Analysis of various material properties of the Mg-Al-CO3 LDH was performed using Fourier transform spectroscopy (FTIR), powder X-ray diffraction (pXRD), thermogravimetric analysis (TGA), and field emission-scanning electron microscopy (FE-SEM). Furthermore, The adsorption kinetics of phosphate(V) ions on Mg-Al-CO3 LDH was studied using spectrophotometric techniques and was found to fit the Langmuir isotherm model, following a pseudo-second order rate law. Moreover, the results suggest the adsorption of phosphate(V) ions unto Mg-Al-CO3 LDH is dependent on chemisorption. (C) 2020 Elsevier Ltd. All rights reserved.