Greener approach for fabrication of antibacterial graphene-polypyrrole nanoparticle adsorbent for removal of Mn2+ from aqueous solution

Herein, novel, efficient and multifunctional heavy metals adsorbent is developed. Graphene sheets are facilely prepared using ultrasonication process with the aid of polyethyleneglycol. Then, spherical polypyrrole nanoparticles of an average size of 150 nm are polymerized on the surface of prepared graphene sheets using green method yielding nanocomposite. The developed graphene-polypyrrole nanocomposite is exploited for removal and recovery of Mn2+ from aqueous solution. The developed graphene-based nanocomposite achieved superior adsorption efficiency for removal of Mn2+ ions than polypyrrole nanoparticles of similar particle size. The new adsorbent achieved excellent removal efficiency of Mn2+ ions recording 89%. Additionally, the smart adsorbent shows antibacterial properties toward Staphylococcus aureus bacteria providing a clear bacterial inhibition zone of 10 mm. The influence of various adsorption parameters of adsorbent dose, contact time and initial metal ions concentrations on the adsorption Mn2+ are studied and optimized. The adsorption of Mn2+ ions on the nanocomposite is also evaluated using Langmuir and Freundlich models and the adsorption isotherms of Mn2+ are suitable and described well with the Langmuir model. Therefore, this study presents a new approach for the design and engineering of safe handling and processing of antibacterial adsorbent for efficient removal and recovery of heavy metal ions from wastewater.