Investigation of boron adsorption by graphene oxide: equilibrium, kinetic, and thermodynamic studies

Abstract

Graphene oxide, which has a great application in industry, is one of the promising carbonous materials. Modified Hummers method was applied to synthesize graphene oxide. Characterization techniques showed that pure graphene oxide was successfully obtained. Its adsorptive properties were investigated by boron adsorption. The results were demonstrated that boron adsorption on graphene oxide was a pH-dependent process and maximum adsorption was achieved at pH 6 (0.98 mg g-1). Langmuir adsorption capacity was calculated as 3.92 mg g-1 with R2 = 0.99. The kinetic data brought to light that pseudosecond-order kinetic model was well described the experimental data (R2 = 0.99), and according to thermodynamic parameters, boron adsorption has spontaneous and endothermic nature (& UDelta;Ho=15.47 kJ mol-1).