Chemical functionalization graphene oxide for the adsorption behavior of bismarck brown dye from aqueous solutions

Abstract

The adsorption behavior of cationic dye Bismarck brown BB onto graphene oxide GO, graphene oxide derivatives 3,3-Diaminobenzidine GODAB, and Ethylene diamine tetraacetic acid-modified graphene oxide GODABE as adsorbents from aqueous solutions were investigated, and characterized by various techniques, like Fourier transform infrared spectroscopy, Field Emission Scanning Electron Microscopy, and X-ray diffraction spectroscopy. Adsorption of BB dye on modified graphene oxide was explored in a series of batch experiments under various conditions. The data were analyzed using Langmuir and Freundlich, models. The Langmuir model was found to be more suitable for the experimental data than other adsorption models. The maximum adsorption capacities were 714.28, 1428.5, and 1111.1 mg/g for GO, GODAB, and GODABE at optimum pH 3 for GO and GODAB, 5 for GODABE and the optimum agitation time were chosen as 45min for GO and 30min for both adsorbents GODAB and GODABE. Kinetic studies revealed that the pseudo-second-order model showed the best fitting to the experimental data. The thermodynamic parameters imply that the adsorption process was spontaneous and endothermic.