Journal of

Background and Objective: Fluoride is one of the essential elements of water that introduce to water resources through several natural and human activities ways. The benefits and risks of fluoride depend on concentration of this anion on drinking waters. In this research, defluoridation of aqueous solution with graphene nanoparticles was studied.

Methods: In the present study, effects of pH, contact time, fluoride initial concentration, adsorbent dosage, temperature as well as presence of sulfate anion in performance of graphene nanoparticles in removal of fluoride from aqueous solution were investigated. Langmuir and Freundlich isotherms also were evaluated.

Results: Maximum adsorption capacity occurred in first 15 minutes in pH=3 and initial fluoride concentration of 10 mg/L. The results also show that adsorption of fluoride on graphene well fitted with Freundlich isotherms. In presence of the sulfate anion, the adsorption capacity decreased. Furthermore, Increasing of temperature led to reducing the adsorption capacity that indicative of exothermic adsorption reaction.

Conclusion: According to results of this research, graphene have good adsorption capacity in removal of fluoride from aqueous solution.