Adsorptive removal of Pb (II) ions from aqueous solution using CuO nanoparticles synthesized by sputtering method

Abstract

Present work deals with the synthesis of copper oxide nanoparticles using reactive magnetron sputtering technique and its adsorptive removal properties for the Pb (II) ions from the aqueous solution. The characterizations of synthesized nanoparticles were carried out using powder XRD, FT-IR, Raman, FE-SEM, EDS, TEM, SAED, BET surface area techniques. The XRD result exhibits monoclinic phase with average crystallite size ~9nm. Raman analysis further confirms the XRD data. TEM result exhibits spherical type morphology having particle size 9nm. The surface area was found to be sufficiently high (82.821m2/g) for adsorption. Different adsorption parameters such as solution pH, adsorbent dose, initial metal ion concentration, equilibrium contact time and temperature were studied for the removal of maximum Pb (II) ions. The optimum parameters were found to be pH6, contact time 3h, adsorbent dose 2g/L for 50mg/L Pb (II) ion concentration. The adsorption kinetics follows pseudo second-order kinetic model which indicates that the adsorption controlled through chemisorption process. The adsorption isotherm follows Langmuir isotherm with maximum adsorption capacity 37.027mg/g. The ΔS and ΔH values were found to be +tive which indicate the endothermic nature of adsorption process whereas –tive value of Gibbs free energy (ΔG) indicates the spontaneous nature of Pb (II) adsorption. The overall study revealed that the synthesized CuO nanoparticles may be an alternative adsorbent for the removal of Pb (II) ions from aqueous solution.