Synthesis of Graphene Oxide as an Adsorbent for the Removal of Bisphenol A

Background: Phenolic compounds are an important group of pollutants in industrial wastewater, which must be treated before disposal into water resources. The present study aimed to use synthesized graphene oxide (SGO) to remove bisphenol A (BPA) from aqueous solutions. Methods: Graphene oxide was synthesized using Hummers' method, and BPA adsorption was assessed as a function of solution pH, contact time, adsorbent dosage, and initial BPA concentration using the batch method. Isotherms and kinetic evaluation of dye adsorption was performed using the equilibrium data. Results: Adsorption was rapid and strongly dependent on pH and adsorbent dosage, reaching the peak at the pH of 7 and adsorbent dosage of 0.8 g/l. BPA removal efficiency at the initial concentration of 10 mg/l was 98.8 ± 0.62%. Analysis of the experimental isotherm data using the Langmuir-Freundlich and Temkin models indicated that the removal process followed the Langmuir isotherm, while the adsorption kinetics followed the pseudo-second-order kinetic model. The maximum adsorption capacity was calculated by Langmuir fitting and determined to be 58.12 ± 1.14 mg/g. Conclusion: According to the results, SGO could be employed as an effective agent for the removal of BPA from aqueous solutions.