Studies in adsorption of some toxic metal ions on citrus sinensis skin and coffea arabica husk: agricultural byproduct

摘要

Adsorption of toxic metal ions like Hg~(2+), Pb~(2+) and transition metal Zn~(2+) ion on different agricultural byproducts were measured by UV-visible spectrophotometer-108. Adsorption of metal ions follows the order polymerized Citrus sinensis (mosambi) skin > Coffea arabica (coffee) husk for Hg~(2+) and Pb~(2+) and Citrus sinensis skin < Coffea arabica husk for Zn~(2+) metal ion. Citrus sinensis skin showed maximum adsorbing capacity for Hg~(2+) and Pb~(2+) metal ions. It could also be seen that Hg~(2+) metal ion is a good adsorbing adsorbate as compared to Pb~(2+) and Zn~(2+) metal ions. The values of Freundlich constants (n and k) are estimated from graph which are found to be 1 < 1 and k > 1.