Adsorption of Cu(II) ions from aqueous solutions using <i>Pinus kesiya</i> biomass

The present study attempted to analyze the biosorption behavior of pine leaves (Pinus kesiya) biomass to remove Cu(II) ions from aqueous solutions. The effects of pH solution, contact time, initial metal concentration and temperature on adsorption capacity were examined in batch experiments. The characterisation studies were carried out using Scanning Electron Microscope (SEM) and Fourier Transform Infrared Spectrometer (FTIR). Freundlich and Langmuir isotherm models were used to describe the adsorption behaviour of Cu(II) ions onto pine leaves. The maximum adsorption capacities (qmax) estimated from the Langmuir isotherm model were 20.88 mg/g. Adsorption mechanism was explored by Pseudo first-order and Pseudo second-order kinetic models, and it was found that the process followed second order kinetics. This study demonstrates that P. kesiya leaves are promising adsorbent for the removal of Cu(II) ions from aqueous solution owing to its high adsorption capacity and, especially, naturally and abundantly available at a low cost.