Computational analysis of kinetic modeling and micromechanism of fluoride ion adsorption process on metal composite surfaces

Fluoride contamination in water bodies is one of the serious environmental problems, and groundwater fluoride contamination is a constraint affecting the use of groundwater and even a threat to human health.Therefore, it is necessary to find widely applied and cost-effective methods for fluoride removal from water bodies.In this paper, we express the adsorption kinetics by constructing the reaction rate equation of the adsorption process and investigate the adsorption mechanism in the adsorption process by quasi-primary and quasi-secondary kinetic models.Langmuir isothermal and Freundlich isothermal models were set up sequentially to design the intermittent adsorption test.X-ray diffraction analysis and Fourier transform-infrared spectroscopy were used to calculate the kinetic and microscopic mechanisms of fluoride ions on the surface of metal composites.The fit R of the proposed secondary kinetics at reagent concentrations of 10 mg/L, 30 mg/L and 100 mg/L were all 0.9999, and the fit of the proposed secondary kinetics model was much higher than that of the proposed primary kinetics model.A new peak was observed at 702.4553 eV for activated alumina (GAA) C, indicating the successful loading of fluoride species onto the GAA adsorbent.