DEVELOPMENT OF GRAPHENE OXIDE/MNO2 NANOCOMPOSITES FOR THE REMOVAL OF SOME HEAVY METALS FROM AQUEOUS MEDIA

Abstract

    Graphene oxide by precipitation method, and was used as a novel adsorbent for theremoval of some heavy metals from aqueous media. The synthesized sorbent wascharacterized by SEM, IR, Laser Diffraction Particle Size Analyzer and EDX. Through achemical deposition method, MnO2 nanoparticles with a typical size of 50 nm werehomogeneously dispersed onto graphene oxide surface. The sorption behavior of someheavy metals on GO/MnO2 was investigated under ambient conditions. The maximumadsorption capacity of GO/MnO2, MnO2 and GO obtained from Langmuir isotherms forPb2+ were 333.3 mg/g, 61.3 mg/g and 82.0 mg/g; for Ni2+ were 208.3 mg/g, 58.1 mg/gand 80,6 mg/g; for Cu2+ were 99.0 mg/g, 37.6 mg/g and 61.0 mg/g, respectively. Themaximum adsorption capacity (qmax) of materials for Pb2+, Ni2+ and Cu2+ was classifiedas follows: qmax(GO/MnO2) > qmax(GO) > qmax(MnO2). When comparing thecompetitiveness in sorption capacity of GO/MnO2 for 3 metals namely lead, copper andnickel, the order of magnitude of sorption capacity expressed in (mmol/g) was found to bein the following oder Ni2+ > Cu2+> Pb2+.