▎ 摘 要
A novel high-capacity phosphate removal adsorbent of graphene nanosheets (GNS) supported lanthanum hydroxide (LaOH) is prepared. The phosphate adsorption performance for GNS-LaOH is examined by a batch adsorption method from aqueous solutions. The Freundlich and Langmuir models are used to simulate the sorption equilibrium, which reveal that the Langmuir model has a better correlation with the experimental data. The maximum adsorption capacity is calculated to be 41.96 mg/g. The kinetic data from the adsorption of phosphate is suggested as the pseudo-second-order model, and the multi-linearity adsorption process is observed in the intraparticle diffusion model, indicating that a chemisorption process is dominant in the adsorption of phosphate. The phosphate adsorption mechanism is explored by analyzing the Fourier transform infrared spectroscopy (FT-IR) and the relationship between the adsorption amount and the pH value of phosphate solution. Ligand exchange and electrostatic and Lewis acid-base interactions are determined to be three main factors for phosphate adsorption.