Synthesis and Characterization of Graphene Oxide Nano-sheets for Effective Removal of Copper Phthalocyanine from Aqueous Media

Graphene Oxide (GO) nano sheets was synthesized from graphite by Hummers method. The nature and morphology of the GO were characterized using FTIR, UV-Vis, SEM and XRD analysis. Batch sorption experiments were carried out to remove copper (ii) phthalocyaninetetrasulfonic acid tetrasodium salt [Cu(tsPc)-4.4Na+] from its aqueous solutions using GO as an adsorbent. Experiments were carried out to investigate the influence of contact time, initial dye concentration, ionic strength, and temperature on the adsorption performance. The Langmuir and Freundlich isotherm models have been applied and the Freundlich model was found to be fit with the equilibrium isotherm data. The kinetic data were analyzed using pseudo first-order and pseudo-second-order models. The adsorption kinetics matched well with the pseudo-second-order kinetic model. The thermodynamic analysis showed that the adsorption process is spontaneous and endothermic. The experiments showed that GO is very good adsorbent with high adsorption capacity for [Cu(tsPc)-4.4Na+] dye and the main reason for this good affinity of dye onto GO can be π-π stacking interactions between the polycyclic aromatic structure of (CuTSPc) and unsaturated bonds on the surface of graphene oxide.