Study of the equilibrium of the adsorption of methylene blue and methyl orange onto super sand.

The present work describes a coating process that was carried out on the surface of graphene oxide powder. Coated material (GO−Sand composite) prepared by soaking screened and washed sand particles (100 µm) with 3% aqueous solution. done in two stages, first at temperature 105 ◦C for three hours then 150 hours. FTIR spectroscopy used to investigate graphite . Adsorption methylene blue methyl orange dyes onto coated experimentally using batch apparatus controlled conditions stirring. Effects initial dye concentration adsorption were examined. analysis equilibrium isotherms shows experimental data follows Fruendlich isotherm model coefficient variance (R2) equals (0.99). This indicates both GO−sand heterogeneous multilayer molecules.  Furthermore, basic thermodynamic parameters calculated most well known relationships. results indicate is spontaneous exothermic as values Gibbs free energy changes lies between -37.078 -24.231 kJ/mole enthalpy -0.669 -0.348 dyes. Finally, activation determined Arrhenius equation found be 28.643 kJ/mol 20.224 adsorption, respectively. proves physical nature adsorbent.  &nbsp