Removal studies of Pb (II) ions by carbon powder prepared from pοlyethylene terephthalate (PET) bοttles

Abstract

ABSTRACT In this study, an innovative low-cost carbon powder that is obtained by pοlyethylene terephthalate (PET) bοttles waste was investigated for the removal of Pb (II) ions from aqueous solution. For this, carbon sample was characterised by a liquid displacement method, point of zero charge pH (pHPZC), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). In addition to this, batch experiments were carried out to study the effect of the main parameters such as contact time, initial Pb (II) concentration, adsorbent dosage and pH of the medium on the adsorption process. As results, the maximum adsorption capacity reached 97.95 mg.g−1 with an initial Pb (II) concentration of 100 mg.L−1, pH = 6.0, sorbent concentration of 0.4 g.L−1, agitation speed of 360 rpm, and temperature of 20°C. Dynamic studies using the solver add-in with Microsoft Excel showed that the adsorption of Pb (II) is well described by a pseudo-second-order kinetic model, while its equilibrium isotherm analysed by Langmuir, Freundlich, Redlich–Peterson and Sips models confirmed that the Langmuir isotherm model is in good agreement with the experimental data of the process. From environmental and economic view, the results of the present study show that PET waste is advantageous and an effective adsorbent for the elimination of lead from aqueous solutions.