Equilibrium and Kinetic Studies on the Removal of Cu(II) from Aqueous Solution Using Acid Treated Modified Rice Husk: A Comparative Study

This study deals with the removal of Cu(II) using rice husk and its acid treated modified form as adsorbents under batch experiments. Different parameters have been investigated for the adsorption of copper metal. Equilibrium time (90 min) was found for copper adsorption. Maximum percentage for removal of Cu(II) was found at pH=4 both for raw rice husk and its treated form. Percentage removal of copper metal was up to 90% for treated rice husk and up to 70% for raw form of rice husk. Calculated saturation capacity of rice husk for Cu(II) were found as 36.587mg/g and 45.267 mg/g for raw and treated rice husk respectively. The amount of Cu(II) adsorbed increased with increase in their contact time. 40 to 50% metal ions were removed within 2030 min after the start of the adsorption. The pseudo second order kinetic model provided the best correlation of the used experimental data compared to the pseudo first model with a R-2 of 0.984 and 0.979 for raw rice husk and treatedrice husk respectively.