A rapid and efficient adsorptive removal of lead from water using graphene oxide prepared from waste dry cell battery

Abstract

Lead (Pb) is a concerning water pollutant worldwide as it is highly toxic to living organisms. In this research, adsorption studies were carried out for the removal of Pb from water. Graphene oxide (GO) was used as adsorbent, which was synthesized by modified hummers method using graphite from waste dry cell battery. The prepared GO was characterized by FESEM, TEM, XRD, BET, Raman, FTIR, and Elemental analysis which revealed that the highly porous GO was successfully prepared from graphite rod of waste dry cell battery. Batch experiments were performed to investigate the effects of pH, contact time, adsorbent dose on the adsorption process, and optimum condition for adsorption was determined. Experiments showed 98.87% removal of Pb (10 ppm) in a very short time (20 min) at pH 4 while adsorbent dose was 0.25 gL−1. The oxygenated groups on the surface of GO played a crucial role in the adsorption of Pb on GO. Experimental data were tested against kinetic and adsorption isotherm models. The adsorption process followed pseudo-second-order kinetics, Langmuir isotherm at lower temperature (20 and 30 °C), and Freundlich isotherm at higher temperature (40 °C). The maximum adsorption capacity was calculated to be 55.80, 54.03, and 51.83 mg g−1 at 20, 30, and 40 °C, respectively. Thermodynamic studies suggested the adsorption was exothermic and spontaneous under 20–40 °C, which indicates that adsorption was feasible. Therefore, this study represents a rapid and efficient method in reducing water contamination caused by Pb.