Carbon Modified Pumice as a New Adsorbent for the Rapid Removal of Fluoride Ions From Aqueous Phase

Carbon modified pumice (CP) was successfully synthesized for the rapid removal of fluoride ions from the solvent phase. The batch experiments were conducted to investigate the effect of several operational parameters including carbon content, solution pH, initial fluoride concentration, contact time, adsorbent dose, and temperature on the CP efficiency in fluoride adsorption. The surface morphology, as well as the structural and functional groups of the synthesized CP were evaluated using the scanning electron microscopy (SEM), Brunauer, Emmett and Teller (BET) method, X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR), respectively. The adsorption isotherm and kinetic data were found to be in good agreement with the Langmuir and pseudo-second-order models, respectively. Finally, the negative value of ΔG° revealed the spontaneous nature of the fluoride adsorption onto the CP adsorbent.