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The present work aims at investigating the potentialities of implementation of electrodialysis for the recycling of spent lithium-ion batteries. In this work, the use of highly-selective membrane toward lithium(I) in electrodialysis was investigated to recover selectively lithium(I) toward cobalt(II), nickel(II) and manganese(II) by means of monovalent ion-selective membranes. It was shown that the presence of divalent cations in the leach solution is responsible for a significant decrease of the limiting current despite an increase in ionic conductivity. Therefore, monitoring the ionic conductivity was not sufficient to operate electrodialysis under optimal conditions, especially when highly selective membranes were used. Furthermore, it was demonstrated that the current has to be lower than the limiting current to avoid metal hydroxide precipitation into the membrane porosity by monitoring the limiting current over time.

The water resources in Tunisia are very limited and not fairly distributed: 80 % of them are located in the north and only 20 % in the south. In addition, 50 % of them are characterized by a bad quality since they have salinity greater than 1.5 g L −1. The bad quality is not only due to the high salinity, but also to the presence of natural pollutants such as fluoride. In fact, according to physicochemical analyses of samples of tap waters collected by the Regional Service of Environmental Health from different monitoring sites in mining area (south of Tunisia), in February 2014, it was shown that waters were contaminated by fluoride and contained high concentrations of sulphate and chloride anions. Fluoride concentrations varied between 0.8 and 4 mg L −1 , and then, greatly exceeded the World Health Organization (WHO) standards in some monitoring sites. In this study, the electrodialysis (ED) technique was applied to remove fluoride from these waters. Experiments were carried out using a pilot unit as a conventional ED in batch recirculation mode. It was shown that ED is an efficient technique to remove fluoride and to reduce salinity of water. Removal rate of fluoride tended to 92 % and the concentrations of different species in the treated water were below the amounts recommended by WHO for drinking water. Considering the effect of chloride and sulphate on fluoride removal through the anion exchange membrane, the performance of two types of ion exchange membrane (PC Cell and Neosepta) was compared. Experiments were carried out with synthetic solutions containing 0.0357 mol L −1 of NaHCO 3 doped with 15 mg L −1 of fluoride. Sodium hydrogenocarbonate was replaced by sodium chloride or sodium

The aim of this work is to study the desalination of brackish water by electrodialysis (ED). A two levelthree factor (2 3 ) full factorial design methodology was used to investigate the influence of different physicochemical parameters on the demineralization rate (DR) and the specific power consumption (SPC). Statistical design determines factors which have the important effects on ED performance and studies all interactions between the considered parameters. Three significant factors were used including applied potential, salt concentration and flow rate. The experimental results and statistical analysis show that applied potential and salt concentration are the main effect for DR as well as for SPC. The effect of interaction between applied potential and salt concentration was observed for SPC. A maximum value of 82.24% was obtained for DR under optimum conditions and the best value of SPC obtained was 5.64 Wh L -1 . Empirical regression models were also obtained and used to predict the DR and the SPC profiles with satisfactory results. The process was applied for the treatment of real brackish water using the optimal parameters.