Defluoridation of septentrional Sahara water of north Africa by electrocoagulation process using bipolar aluminium electrodes

The purpose of this paper is to suggest an efficient defluorination process which does not require a big investment. For this, the electrocoagulation process with aluminium bipolar electrodes was used. In the first step, the influence of parameters such as inter-electrode distance, fluoride concentration, temperature and the pH of the solution, were investigated and optimized with synthetic water in batch mode. Ln the second step, the optimization process was continued with Oued Souf water (south Algeria) where the influence of the current density and the area/volume ratio on the defluorination process was evaluated. The electrocoagulation process with aluminium bipolar electrodes permitted the defluorination of Sahara water without adding soluble salts to the treated water. The aluminium-fluoride weight ratio attained 17/1. (C) 1998 Elsevier Science Ltd. All rights reserved.