Electrically enhanced adsorption and green regeneration for fluoride removal using Ti(OH)4-loaded activated carbon electrodes

An electrically enhanced fluoride removal method was developed that blended the merits of electrosorption and adsorbent adsorption. This method has the advantages of high adsorption selectivity and capacity for fluoride. The saturated adsorption capacity of Ti(OH)4 for fluoride in the electrode of Ti(OH)4-loaded activated carbon reached 115.2 mg/g when a voltage of +1.2 V was applied to the electrode. The electrode was easily and cleanly regenerated in a short time in aqueous solution with high fluoride concentrations when a voltage of −1.6 V was applied. The adsorption capacity of the Ti(OH)4-loaded electrode for fluoride did not decrease after multiple cycles of electrically enhanced adsorption and regeneration. Excellent adsorption selectivity for fluoride was achieved. The electrically enhanced adsorption method showed potential for fluoride removal.