Removal and Reusability of Lead (II) from Aqueous Samples Using the Adsorption Method onto Commercial Activated Carbon: Kinetics and Thermodynamics Studies

Abstract:

Background and Aim: The study focused on the sorption of lead Pb2+ from water samples using Commercial Activated Carbon (CAC) sorbent. Materials and Methods: The factors affecting the absorbance between Pb2+ and CAC were examined the mass of the CAC, ionic strength, pH solution and effect of temperature on the solution. Isotherm models (Langmuir, Freundlich and Temkin) were examined for Pb2+ adsorption on CAC. Results and Discussion: Freundlich isotherm model was determined as the best lead adsorption model on CAC. Freundlich model parameters R2, n , and kf were found 0.9889, 1.48, 0.53 mg.g-1 respectively. The adsorption capacity (qe) was 12.81 mg.g-1. Thermodynamic parameters ΔH, and ΔS were found -1422.8 and 5.2389 KJ.mol-1 respectively. The adsorption process was exothermic. A Pseudo-Second-Order (PSO) model was followed for the adsorption process. Finally, the method was proved to be highly effective method for the extraction of the Pb2+ using CAC three times. The percentage extractions (%ER) found ranged from 107.0-91.9 % for stimulation marketing drink water and tap water. Conclusion: CAC is distinguished as an adsorbent that excels other adsorbents in removing the Pb2+ from aqueous solutions due to its chemical and physical properties.

Keywords: Lead (II), Commercial activated carbon (CAC), Thermodynamics, Adsorption isotherm models, Kinetics models.