Removal of heavy metal ions using cassava skin

CHED 1140

Lolade Akinola, lakinola@mytsu.tnstate.edu, Chemistry, Tennessee State University, 3500 John A Merritt, Nashville, TN 37209 and Nsoki Phambu, nphambu@tnstate.edu, Department of Chemistry, Tennessee State University, 3500 John A Merritt Blvd, Nashville, TN 37209.
Cassava (Manihot esculenta Crantz) forms an important staple food for more than 500 million people mostly in humid tropics. Cassava is a natural product, biodegradable, and is rich in carbohydrate. This project investigates the ability of cassava skin for heavy metal ion removal from aqueous solutions and compares it with the removal ability of activated carbon. The results obtained using atomic absorption technique show that the cassava skin is able to trap large quantities of metal ions. In some cases, the adsorption capacity of cassava skin is up to two times that of activated carbon. The infrared spectra show that the C-O groups of cassava skin are the binding sites of metal ions. The kinetics of both adsorption and desorption of heavy metal ions from water is fast for all the metal ions investigated. Cassava skin may be used for the removal of radioactive or non-radioactive metal ions.