TITLE:
Sol-Gel γ-Al2O3 Nanoparticles Assessment of the Removal of Eosin Yellow Using: Adsorption, Kinetic and Thermodynamic Parameters
AUTHORS:
Mohamed S. Thabet, Ahmed M. Ismaiel
KEYWORDS:
Eosin Y, Adsorption, Nanoparticles, Aluminum Oxide, Thermodynamic Parameters, Kinetics
JOURNAL NAME:
Journal of Encapsulation and Adsorption Sciences,
Vol.6 No.3,
August
31,
2016
ABSTRACT: The adsorption
behavior of eosin yellow (EY) from aqueous solution onto γ-Al2O3 nanoparticles in batch technique was
studied. γ-Al2O3 NPs was prepared and characterized by SEM, TEM, XRD and FTIR analysis. The
effect of pH, dosage of adsorbent, contact time, temperature, and the initial
concentration of dye was investigated. The maximum amount of dye removal found
about 99.36% at pH4, the adsorption dose 1g/L, with the initial dye concentration of 100 mg/L, and the temperature
of 25°C, with contact time 120 min. The adsorption behavior of the
eosin yellow dye is applicable to Langmuir isotherm model, with the maximum
sorption capacity of 47.78 mg/g of γ-Al2O3.
The kinetic data also described by the pseudo-second-order model with a
correlation coefficient (0.9999), and the mechanism of the process showed a
multi-linear steps and the intra-particle diffusion was not only rate
controlling step. The adsorption process was endothermic with positive enthalpy
of 121.8 kJ/mol, and showed spontaneous process with a mean free energy -5.19
kJ/mol, and increase randomness, 369.77 J/mol. k, at the adsorbent solution
interface. The adsorption process was chemisorption in nature The activation energy estimated from Arrhenius
and modified Arrhenius is 40.9 kJ/mol, 106.37 kJ/mol respectively. The sticking
probability of EY onto Al2O3 NPs very high estimated from
the value of S*