TITLE:
Fe-Oxide Nanomaterial: Synthesis, Characterization and Lead Removal
AUTHORS:
Buzuayehu Abebe, H. C. Ananda Murthy
KEYWORDS:
Nano-Iron Oxide, Sorption Isotherm, Kinetics, Thermodynamics, Lead Desorption
JOURNAL NAME:
Journal of Encapsulation and Adsorption Sciences,
Vol.8 No.4,
November
19,
2018
ABSTRACT: Organic solvent free iron oxide nanomaterial used for lead removal was synthesized
by co-precipitation method. Fourier transform infrared spectroscopy (FT-IR),
scanning electron microscopic with energy dispersive X-ray analysis (SEM-EDX),
X-ray diffraction (XRD) and thermo gravimetric-differential thermal (TG-DTA)
analysis were used to determine the surface characteristics and analysis of
iron oxide. Optimization of solution pH, adsorbent dosage, contact time,
agitation speed and initial lead ion concentration were conducted for further
adsorption isotherm, kinetics, thermodynamics and desorption study. Langmuir
sorption isotherm model fits the adsorption data better than Freundlich, Dubinin-Radushkevich (D-RK) and Flory-Huggins (FH)
models. The mean adsorption energy and
free energy obtained from D-RK and FH
models guides that the mechanism was under control of physical adsorption and
actuality of spontaneous reaction, respectively. From kinetics of adsorption pseudo
second (PSO) model fits well than pseudo first (PFO) and Elovich
adsorption-reaction models. And to test whether the reaction is under control
of adsorption-diffusion or not the intra particle diffusion (IPD) model was
tested, but it fails to pass through the origin. This indicates that the reaction mechanism only under
control of adsorption-reaction. The maximum adsorption capacity (qmax)
of the adsorbent was 70.422 mg/g.