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The synthesis is realised by mixing under strong agitation a solution of hydrated sodium aluminate, a solution of sodium silicate and the water. The mixture was then transferred to a polytetrafluoroethylene bottle, which was sealed and rotated in an oven at 100°C for 18 hours. The white crystalline product was filtered off, washed thoroughly with distilled water, and dried. The chemical analysis of the crystal have shown that the zeolite possesses a typical chemical formula: Na5 [(AlO2)5 (SiO2)11]; 11,5 H2O.The water contents were determined as % weight loss in a thermobalance. The zeolite NaP is characterized by a ratio Si / Al equal to 2,2 and a capacity of exchange of 4,7 meq/g.All exchange were determined at 25°C in agitated thermostats (at least for 5 days). The portions of zeolite and solution were then separated for analysis of the two ions. The results of the elimination have shown that the zeolite NaP can reduce clearly the ions Pb, NH4, Cd and Fe. By plotting the isotherms of exchange, one has shown that the zeolite has made proof of the preference for these four ions. On the other hand, it is particularly not selective for the ions Mg, Mn and Ni in comparison with Na. The copper and the zinc have shown a partial saturation of the zeolite that is having to the suitable that some sites of exchange are inaccessible to these two ions. The order observed decreasing selectivity is: Pb2+ &gt; NH4+ &gt; Cd2+ &gt; Fe2+ &gt; Cu2+ &gt; Zn2+ &gt; Mg2+ &gt; Mn2+ &gt; Ni2+For the regeneration, we have sought to determine optimal conditions under which one can recuperate the totality of already exchanged ions.The regeneration with solutions of concentration in sodium in the order 120 meq/l provides a material whose aptitude to a new fixing of toxic ion is analogous which the original material. The rate of regeneration exceeds 95%. The zeolite is therefore a material that can serve in the area of ion elimination, especially for Pb, Cd, Fe and NH4 in order that it shows a particularly great affinity. Dans cette étude, la zéolithe NaP est utilisée pour l’élimination de certains cations contenus dans les eaux : Pb, NH4, Cd, Fe, Cu, Zn, Mg, Mn et Ni. C’est un matériau facile à préparer et qui présente un rapport Si/Al faible, ce qui lui confère une capacité maximale d’échange importante (4,7 méq/g). Les analyses chimiques et thermogravimétriques ont conduit à la formule suivante :Na5 [(AlO2)5 (SiO2)11] ; 11,5 H2O.Les résultats de l’élimination ont montré que la zéolithe NaP peut réduire nettement les ions Pb, NH4, Cd, Fe, Cu et Zn. Les isothermes d’échange montrent que la zéolithe NaP fait preuve, par rapport au sodium, d’une préférence pour ces ions. En revanche, elle est particulièrement peu sélective pour les ions Mg, Mn et Ni.L’ordre de sélectivité observé est :Pb2+ &gt; NH4+ &gt; Cd2+ &gt; Fe2+ &gt; Cu2+ &gt; Zn2+ &gt; Mg2+ &gt; Mn2+ &gt; Ni2+La régénération, par des solutions salines de concentration en sodium de l’ordre de 120 meq/l, fournit un matériau apte à une nouvelle utilisation.

Possibilité d’élimination de cations toxiques contenus dans les eaux au moyen d’une zéolithe synthétique NaP