Adsorption of Trivalent Antimony from Aqueous Solution Using Graphene Oxide: Kinetic and Thermodynamic Studies

Graphene oxide (GO) used as adsorbent torerritive trivalent antimony (Sb(III)) from aqueous solution. was studied. Xray diffraction, Faurier transform infrared, scanning :electron microscopy, X-ray photoelectron spectroscopy; and energy dispersive X-ray analysis were adopted to characterize the EGO. Batch :experiments were conducted to systematically Investigate adsorption efficiency' and influence of various parameters; such as initial pH, contact tithe, initial Sb(III) concentration, and terriperature. It found that GO was particularly effective for the adsorption of-Sb(III) within a, Wide pH range of 2.0 to 10.0 under test conditions Kinetics of the adsorption process was also studied and the pseudofirst-order rate Model was found to fit experimental data welt-with i-highest correlation coefficient (R-2 > 0.99). The adsorption isotherm data were better modeled with Langmuir isotherm&-than with Freundlich isotherms. The thermodynamic parameters. (Delta H, Delta S, and Delta G) were evaluated, and the results indicated that the-adsorption process of Sb(III) on the GO was spontaneous and endothermic. In addition, a remarkable Sb(III) desorption efficiency was achieved when 0.1 mol.L-1 EDTA solution was applied to the GO absorbingly exhausted with.Sb(III). Further successful eXperinients of consecutive adsorption-desorption cycles suggest that GO could be a promising adsorbent for removal of Sb from the contaminated solutions.