p-Phenylenediamine Functionalized Magnetic Graphene Oxide for the Removal of Congo Red from Wastewater

In this study, A simple and effective nanomaterial aiming at the rapid removal of dye was proposed. The p-phenylenediamine functionalized magnetic graphene oxide nanocomposites (PPDMGO) were prepared as novel adsorbents. The groups, magnetic property and morphology of prepared materials were characterized by Fourier infrared spectrometry (FT-IR), transmission electron microscopy (TEM), and vibrating sample magnetometer (VSM). The PPD-MGO nanomaterial was utilized in the adsorptive removal of Congo red (CR) in aqueous solution. The factors such as adsorption time, adsorption temperature, pH of solution, adsorption kinetics and isotherms were all investigated. The results indicated that the PPD-MGO nanomaterial had good adsorption ability and the maximum adsorption capacity was 651.1 mg/g at 45 °C and pH 5. The adsorption capacity remained at 364.58 mg/g after twenty cycles. Removal rate could reach 98% after four times of adsorption. The adsorption process with CR was found that fitted the pseudo-second-order kinetics equations and the Langmuir adsorption model. The experimental results showed the PPD-MGO nanomaterial could be rapidly extracted from the medium and had a good adsorption ability to remove CR in wastewater.