Removal of fluoride ion from aqueous systems by electrochemical processes

Abstract

The project aimed at decreasing fluoride ion concentration lower than the limits set by the national norms and standards with respect to water quality by using electrochemical methods. The optimal operating parameters were determined for the process of removing fluoride from ground water by electrocoagulation with sacrificial anode made of aluminium placed horizontally and vertically in cells, respectively. The residual fluoride concentration in the electrochemically treated water was lower than 1.2 mg/L, which is the maximum allowable fluoride concentration in drinking water set by Law 458/2002 – concerning water quality, regardless of the electrode configuration. The specific energy consumptions were comparable for the two electrode configurations, 1.40 and 1.30 kWh/m3, respectively, at an initial fluoride concentration of 5.1 and 9.6 mg/L, respectively, current density of 780 A/m3 and 60 min electrolysis duration.