Removal of methylene blue from aqueous solution using graphene oxide nanosheets: kinetic and isotherm study

In this study, graphene oxide nanosheets have been used for the adsorption of methylene blue, a cationic dye from aqueous solution. The physical characteristics of graphene oxide nanosheets studied using Fourier transform infrared (FTIR) and X-ray diffraction (XRD). The adsorption of the methylene blue onto the graphene oxide nanosheets has been carried out at different experimental condition such as contact time (1- 4 hours), adsorbent dosage (0.05 - 0.7 g/l), pH of solution (3 - 9) and initial concentration of dye (50 – 400 mg/l). The results show that the maximum adsorption (910 mg/g) under these conditions; adsorbent dosage of 0.05 g/l, initial concentration of 50 mg/l, two hours contact time and pH=6. The kinetic of adsorption data analyzed using three kinetic models such as elovich model, pseudo first-order model and pseudo second order model. Kinetic study indicated that the maximum adsorption was reached at two hours and follows the linear form of pseudo second-order kinetic model. The adsorption isotherm has been investigated in the pH range of 3 to 9, initial concentration of 50 to 400 mg/l and the adsorbent dosage of 0.05 to 0.7 g/l in 25 °C. The equilibrium data fitted to the Langmuir isotherm model well. Thus, graphene oxide nanosheets can be known as a good adsorbent for the adsorption of cationic pollutants.In this study, graphene oxide nanosheets have been used for the adsorption of methylene blue, a cationic dye from aqueous solution. The physical characteristics of graphene oxide nanosheets studied using Fourier transform infrared (FTIR) and X-ray diffraction (XRD). The adsorption of the methylene blue onto the graphene oxide nanosheets has been carried out at different experimental condition such as contact time (1- 4 hours), adsorbent dosage (0.05 - 0.7 g/l), pH of solution (3 - 9) and initial concentration of dye (50 – 400 mg/l). The results show that the maximum adsorption (910 mg/g) under these conditions; adsorbent dosage of 0.05 g/l, initial concentration of 50 mg/l, two hours contact time and pH=6. The kinetic of adsorption data analyzed using three kinetic models such as elovich model, pseudo first-order model and pseudo second order model. Kinetic study indicated that the maximum adsorption was reached at two hours and follows the linear form of pseudo second-order kinetic model. The adsorption isotherm has been investigated in the pH range of 3 to 9, initial concentration of 50 to 400 mg/l and the adsorbent dosage of 0.05 to 0.7 g/l in 25 °C. The equilibrium data fitted to the Langmuir isotherm model well. Thus, graphene oxide nanosheets can be known as a good adsorbent for the adsorption of cationic pollutants.Thus, graphene oxide nanosheets can be known as a good adsorbent for the adsorption of cationic pollutants.