Graphene Oxide Nanosheets as An Efficient and Reusable Sorbents for Eosin Yellow Dye Removal from Aqueous Solutions
Journal
ChemistrySelect
Journal Volume
2
Journal Issue
13
Pages
3598-3607
Date Issued
2017
Author(s)
Veerakumar, P.
Tharini, J.
Ramakrishnan, M.
Panneer Muthuselvam, I.
Lin, K.-C.
Abstract
In this study, 2D graphene oxide nanosheets (GONS) were synthesized and characterized by XRD, Raman, SEM, FE-SEM, TEM, XPS, TGA, UV-vis and FTIR spectral techniques. The efficiency of eosin yellow (EY) dye adsorption on the GONS under various experimental parameters such as contact time, pH and temperature was investigated. Adsorption kinetic data were characterized appropriately using pseudo second-order-kinetics and intraparticle diffusion methods. Free energy of adsorption (ΔG0), enthalpy (ΔH0), entropy (ΔS0) changes, activation energy and Arrhenius factors were also calculated. The endothermic and spontaneous nature of the adsorption process was confirmed by the positive value of the enthalpy change (ΔH0) and the negative value of free energy change (ΔG0). The adsorption mechanism was investigated by FTIR spectra of GONS before and after adsorption of EY dye molecules. The remarkable adsorption capacity of EY onto the GONS can be attributed to the various adsorption interaction mechanisms such as hydrogen bonding, π-π electron, and electrostatic interactions. The maximum adsorption capacity for EY was calculated to be 217.33 mg g-1.
Type
journal article