In this study, the
removal of methylene blue dye (MB) from aqueous
solution was examined using a novel green adsorbent to overcome the
obstacles encountered in chemical methods. Ricinus
communis (RC) aqueous seeds extract was herein used
as a reducing and capping agent to synthesize a novel nano-zero-valent
iron (RC-nZVI) for the adsorption of harmful MB. Structural and morphological
characterization of the synthesized RC-nZVI were performed using several
techniques, e.g., steady-state absorption, scanning electron microscopy
(SEM), transmission electron microscopy (TEM), Fourier transform infrared
(FT-IR), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction
(XRD), X-ray photoelectron spectroscopy (XPS), and zeta potential.
The maximum efficiency of the removal was 96.8% at pH 6 and 25 °C.
According to the kinetics study results, the adsorption process obeys
the pseudo-first-order model. The experimental equilibrium data were
fitted to the Freundlich isotherm model, the maximum adsorption capacity
reached was 61.37 mg·g–1, and the equilibrium
parameters were determined. The synthesized RC-nZVI possesses good
reusability and can be considered as a potential economic and environmentally
friendly adsorbent.