Etude expérimentale de l'effet de l'enrobage de supports solides par des polymères conducteurs sur leur capacité de rétention des cations métalliques en solution aqueuse par adsorption . Application à la silice et à certains materiaux naturels.

Abstract

Among the industrial wastewater treatment techniques, adsorption has shown great capabilities for the elimination of a great number of pollutants, particularly certain heavy metals carried by certain industrial effluents. However its performance depends on the nature of the used solid support. In the present work, an experimental study concerning the influence of the coating by certain conductor polymers, such as polyaniline, of certain natural solid materials such as the silica gel, olive seeds and peanut shells, on their capacity on retaining metallic cations, such as copper, cadmium, zinc and lead, has been carried out. The main objective is not the coating process itself, but the use of the solid support once coated. The obtained results have shown that the coating of these solid supports has greatly contributed to improve the adsorption capacity of the considered metallic specie The study has enabled to determine the adsorption isotherms as well as to study the influence of certain fundamental parameters such as the contacting time, the initial concentration, the solution pH, the adsorbent particle sizes, the agitation speed, etc., on the adsorption capacity. The results have also shown that the four considered bivalent cations (Cu2-, Cd2-, Zn2- and Pb2+) have very similar behaviours with respect to the three solid support used (silica gel, olive seeds, peanut shells), after coating by the polyaniline.