Pb²⁺, Cd²⁺ and Hg²⁺ removal by designed functionalized swelling high-charged micas

The increasing accumulation of toxic heavy metals in the environment has generated the need of efficient removal systems, being the adsorption method the most popular one applied in aqueous solutions. Of particular concern is the case of Pb²⁺, Cd²⁺ and Hg²⁺ due to their high potential hazard. In this paper, we describe the feasibility of a new family of nanomaterials, swelling high charge micas, in the removal of these cations from aqueous solutions. Batch adsorption experiments were carried out in the as-made micas, NaMn, and after functionalization with ethylammonium, EA-Mn, and mercaptoethylammonium, MEA-Mn. The results have demonstrated that all of them are efficient heavy metal adsorbents, being Na-M2 the best adsorbent for Pb²⁺ and Cd²⁺_, and, MEA-M2 for Hg²⁺.