Adsorption of fluoride by clays from the potential sites for acid waste storage

Noureddine HAMDI1*, Ezzeddine SRASRA1 1Unite de recherche sur les materiaux, Institut National de recherche scientifique et technique, Tunis, BP 95-2050 Hammam lif, Tunisia ; *Corresponding Author: email: hamdinoureddine@yahoo.fr The aim of this work, consists to evaluate the potential effectiveness of clays coming from three sites (MK, H and ZB) intended for the storage of acid industrial waste Charged by F-. The interaction between fluoride and clays is affected by some parameters: pH, contact time, type of clays and initial fluoride ion concentration. Firstly, we examined the adsorption of fluoride from NaF solution at various concentrations and pHs (3, 4, 5,5 and 6,5). We concluded that for each sample the maximum fluoride sorption capacity was found at pH 3. In the second step, the study of fluoride adsorption on clay is carried out by the solution of accompanying waste (pH between 2-3 and F– concentration is 2360 mg/l). MK palygorskitic clay was showed to be a superior fluoride sorbent than other samples. Keywords: Clays, Fluoride adsorption, Waste storage.