Exploring the adsorption process of Cu (II) on natural bitumen

Heavy metals are one of the major environmental concerns due to their toxicity. These contaminants find their way into the soil, air and water due to natural processes, such as physical erosion or chemical degradation, but mostly due to anthropogenic sources [1]. Copper is a required element for human metabolism but in high dosage it causes some disease such as Anemia, changing in bones structure and etc [2] .In the present work, proficiency of a natural polymer named Natural Bitumen for removal of Cu (II) cation from aqueous solution was investigated by using of batch experiments. Effect of various factors such as pH, contact time, adsorbent dosage, adsorbate concentration and temperature on adsorption process of Cu(II) cations was explored. Equilibrium isotherm studies were examined by application of different conventional models such as Langmuir, Freundlich and Tempkin models to explain the experimental data. Based on considering R2 value as criterion the adsorption data well fitted to Langmuir model. To investigate the mechanism of adsorption, thermodynamic parameters such as free energy (ΔG), enthalpy (ΔH), and entropy (ΔS) of the system were evaluated. Thermodynamic studies show that adsorption process is exothermic and spontaneous.