Nickel(II) and cadmium(II) uptake by carbon iron composite derived from Pelargonium graveolens

In this research, a carbon iron composite was produced from the leaves of Pelargonium graveolens for the sorption of Ni 2+ and Cd 2+ ions. The carbon was activated with phosphoric acid and then functionalized with iron oxide using a precipitation method. The composite was characterized using several techniques. FTIR spectroscopy confirmed the formation of a metal oxide peak at 540 cm −1 . TEM microscopy showed cubic and spherical nanoparticles on the surface of the carbon-iron composite. The XRD pattern of the iron composite showed peaks corresponding to Fe 3 O 4 . Batch sorption studies were performed using different operating parameters, namely, contact time (1–85 min), pH (2–10), temperature (30, 40, 50, 60, and 70 °C), and concentration (25, 50, 75 and 100 mg/L) for the removal of Ni 2+ and Cd 2+ ions. The elevated uptake of Ni 2+ and Cd 2+ best fitted the Langmuir isothermal model. The maximum experimental adsorption capacities for Ni 2+ and Cd 2+ ions were 46.62 and 58.94 mg/g, respectively. The kinetic studies of Ni 2+ and Cd 2+ ions on the carbon-iron composite were expressed by a pseudo-second-order kinetic model (PSO). The experimental data showed that P . graveolens can be converted into a useful carbon iron composite sorbent for the removal of Ni 2+ and Cd 2+ in a water environment.