KINETIC AND THERMODYNAMIC MODEL FOR THE REMOVAL OF ULTRAMA- RINE BLUE FROM AQUEOUS SOLUTION USING MODIFIED CASSAVA PEELS

This work presents the kinetic and thermodynamic model for the sorption of ultramarine blue on modified cassava peels. The effects of various experimental parameters such as adsorbent dosage, contact time, pH, concentration and temperature were investigated. The extent of ultramarine re- moval increased with increase in adsorbent dosage, contact time, concentration and temperature. The data obtained fitted to the Langmuir isotherm. The Sf value, which is the separation parameter was obtained as 0.633, indicating that the biomass is an excellent adsorbent for ultramarine blue. The Freundlich Model estimated the adsorption intensity (R2) as 0.993. The R2 value and the Line- ar plot obtained showed that the Freundlich isotherms favours the adsorption process. Pseudo-first and pseudo-second order kinetics were used to analyse experimental data and it was found that both models described the data very well. Thermodynamic parameters like free energy (ΔG), en- thalpy (ΔH) and entropy (ΔS) of the system were calculated by Langmuir constant (k) and it was found that the adsorption process was endothermic in nature.