Adsorption of Cu(II) and Pb(II) onto bacterial cellulose-co-polyacrylamide: A study of equilibrium adsorption isotherm

Abstract

Radiation-induced graft polymerization using gamma rays was used in our previous study to synthesize a bacterial cellulose co-polyacrylamide adsorbent (BC-PAAM). In this work, the adsorption capacity of the adsorbent BC-PAAM towards copper and lead metal ions was investigated in a batch adsorption system under various parameters such as the contact time and the initial concentration of the metal ion. The pH of the metal solution was kept at 5 during the adsorption process. The equilibrium adsorption data is also interpreted from the Langmuir and Freundlich isotherms to find the most appropriate adsorption isotherm system. The results demonstrated that the Langmuir isotherm model was more applicable to describe the adsorption of the BC-PAAM adsorbent to Cu(II) and Pb(II) metal ions than the Freundlich isotherm model. The adsorption data fit well into the Langmuir isothermal model with a correlation coefficient, R2=0.9913 and R2=0.9713 for Cu(II) and Pb(II) adsorption onto BC-PAAM, respectively. While the correlation factor (R2) for Cu(II) and Pb(II) were 0.9755 and 0.922 for the Freundlich isotherm model. The RL value obtained was between zero and one, indicating that the adsorption of both Cu(II) and Pb(II) ions onto BC-PAAM is favorable.