USE OF IMMOBILIZED BENTONITE IN REMOVAL OF HEAVY-METALS FROM WASTE-WATER

Bentonite is known to adsorb toxic metal ions from aqueous solutions. In this study bentonite was immobilized in a polymer matrix of polysul fone in the form of spherical beads to remove cadmium and copper ions. For this purpose a bead-producing unit was fabricated. The procedure for making beads is described. The beads exhibited a porous surface an d surface area of up to 20 m(2)/g. 99.4% of beads were retained on a s ieve size of 1.18 mm and were finer than 2.36 mm. Batch adsorption dat a was adequately described by the Freundlich isotherm model. The beads were able to remove more than 99% of copper and cadmium ions in the c olumn mode. These beads can find application as filter media in the re moval of toxic heavy metal ions from aqueous solutions.