Adsorption of Cd(II), Pb(II) and Cu(II) from multi-metal aquoeus system by alkali-treated alang-alang grass (Imperata cylindrica)

The study of adsorption of heavy metal Cd(II), Pb(II) and Cu(II) in multi-metal system using adsorbents from alang-alang (AL) grass (Imperata cylindrical) was conducted. The purpose of this study was to determine the optimum pH and contact time and also to study the kinetics and isotherms adsorption. The results showed that the optimum pH for adsorption Cd(II), Pb(II) and Cu(II) metals was 4, 6 and 8 respectively. The adsorption kinetics of Cd(II), Pb(II) and Cu(II) was more suitable using the pseudo second order model. Isotherms adsorption for those three metal ion are more fit to the Langmuir isotherm equation with the qmax 3,92 mg/g; 4,43 mg/g and 5,13 mg/g for Cd(II), Pb(II) and Cu(II) respectively. From the experiment result, the AL is more feasible to be adsorbent for Cu(II) in the presence of Cd(II) and Pb(II).