Rhodamine 6G dye adsorption using magnetic nanoparticles synthesized with the support of Vernonia Amygdalina leaf extract (bitter leaf)

Abstract

This study reports the synthesis of magnetic nanoparticles (MNPs) using the co-precipitation method with the support of Vernonia Amygdalina (VA) (bitter leaf) extract for the efficient sequestration of rhodamine 6G dye (Rhd 6G) from a water-soluble solution. The prepared MNPs were characterized using Transmission electron microscopy (TEM,) X-ray Diffraction (XRD), Fourier-transform infrared (FTIR) and Ultraviolet-visible (UV-Vis) spectrometry. The average particle sizes from TEM and XRD analyses were 4.81 ± 2.2 nm and 5.61 nm respectively. The sorption of Rhd 6G dye to the MNPs was pH-dependent, with ideal confiscation of dye molecules observed at pH 10 (. The sorption process of Rhd 6G dye was reported to follow the Freundlich (FRH) isotherm model, while the pseudo-first-order model (PFOM) best depicted the sorption process of Rhd 6G dye to the MNPs from the non-linear modelling. The determined sorption capacity of the MNPs was established to be 454 mg.g−1. Also, the sorption of Rhd 6G dye to the MNPs was observed to be thermodynamically spontaneous, endothermic and with increasing randomness between the interface of the water-soluble solution and the MNPs. Hence, the prepared MNPs have proven to be an effective potential magnetic sorbent for the removal of cationic dyes from an aqueous solution.