Decolorization and Removal of Reactive Red 198 by Nano-Magnetic Graphene Oxide

Abstract

In this research, a systematic study of the adsorption and decolorization process of reactive red 198 (RR198) onto Fe₃O₄-graphene oxide (Fe₃O₄-GO) was applied via various pH, sorption time and temperature. Investigation of reactive red 198 adsorption kinetics were satisfied by the pseudo-first and second order model. According to the kinetic examinations, the equilibrium reached within 15 min following the pseudo-second-order model. The sorption data have interpreted by the Langmuir model with the maximum adsorption of 357.14 mg g^-1 at 298 K and a rate constant of R² = 0.996. The mean energy of adsorption and thermodynamic parameters such as DH°, DS° and DG° values were determined which included the exothermic and spontaneous nature of the sorption process. The results indicated, reactive red 198 vigorously was adsorbed on the Fe₃O₄-GO surface via p–p interaction and cation–p bonding acid under UV Irradiation could degrade the reactive red 198 strongly and within 60 min the reactive red 198 totally disappeared.