ADSORPTION OF A CATIONIC DYE ONTO ZEA MAYS COBS: ISOTHERMS, KINETICS AND THERMODYNAMIC STUDIES

Efficient adsorbent was prepared from the cobs of Zea mays (RZM). Various physicochemical characterization were determined for the RZM and its efficacy in the uptake of Rhodamine B (RhB) was investigated. Adsorption operational conditions were studied and adsorption data were tested using the five isotherm and four kinetics models. Optimum adsorption was obtained at pH 3. Adsorption data fitted best into the Freundlich adsorption isotherm, maximum monolayer adsorption capacity obtained is 500 mg/g. Pseudo second order best describe the kinetics of uptake of RhB onto RZM. The calculated adsorption energy obtained from D-R model was less than 8 kJ/mol suggesting that the uptake of RhB onto RZM was physical in nature