Adsorption of Cd2+ and Pb2+ on Agricultural Byproducts

Abstract

Adsorption of toxic metal ions like Cd²⁺ and Pb²⁺ on different vegetable

and agricultural byproducts were measured at room temperature by atomic

absorption spectrophotometric (AAS) and differential pulse polarography

(DPP) methods. The adsorption of Cd²⁺ follows the order polymerised

onion skin > bagasse > banana husk > suffola husk > spinach; whereas the

adsorption of Pb²⁺ follows the order polymerised onion skin > spinach >

suffolahusk > bagasse > banana husk. Polymerised onion skin shows maximum

adsorbing capacity for both the ions compared to other adsorbents.

The adsorption due to raw onion skin is almost equal to polymerised onion

skin. Therefore it can be suggested that raw onion skin is a better substitute

for polymerised onion skin. Also the raw onion skin would be a more

inexpensive adsorbent than the one modified by a polymer.