Isotherm, Kinetic and Thermodynamic of Adsorption of Heavy Metal Ions onto Local Activated Carbon

Abstract

In this work, the adsorption isotherm, Kinetic and thermodynamic of removal of Fe3+, Cu2+, Pb2+ and Zn2+) ions by activated carbon produced from rice husk were studied. The results shown that the Freundlich isotherm model achieved best fit with the equilibrium adsorption data for adsorption of (Fe3+, Cu2+ and Pb2+) ions, it is indicates to multilayer adsorption nature of these metal ions on RHAC. The adsorption capacity (Kf) of the adsorbent have a value of (312.1, 628.93 and 162.66 mg/g) for (Fe3+, Cu2+ and Pb2+), respectively. The Langmuir isotherm model gives best fit with the equilibrium adsorption data, it is instated to monolayer adsorption nature of (Zn2+) ions on RHAC. The monolayer adsorption capacity (Q) have a value of (714.285 mg/g). The adsorption kinetics were followed the pseudo-second-order model, this model gives the best- fit to experimental data for all heavy metal ions which studied in this work. which have highest correlation coefficient values of (0.988 ,0.996 ,0.999 and 0.9232) for (Cu2+, Fe3+, Pb2+ and Zn2+), respectively. Also, the adsorption thermodynamic showed that the adsorption of heavy metal ions becomes more feasibility with increasing in temperature due to negative values of ΔG. The adsorption process is endothermicdue to positive values of ΔH.