Microwave assisted modification of graphene oxide: Characterization and application for adsorptive removal of cationic dye

Abstract

Abstract Removal of dyes from treated wastewater is intricate problem and to solve that many techniques such as adsorption, advanced oxidation, ion exchange, catalytic degradation and biodegradation etc. are under investigation. Among these, adsorption is considered as most appropriate method. Graphene Oxide (GO) is having wide range of oxygen functional groups, unique electronic, thermal, and mechanical properties which makes it suitable for adsorptive removal of dyes. The present study deals with modification of commercially available graphene oxide by microwave irradiation as efficient and environment affable method. The microwave modified graphene oxide was characterized using Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy, and X-ray Diffraction Techniques and utilized for removal of cationic dye ‘Methylene Blue’ from aqueous solution by batch adsorption study. Adsorptive removal of Methylene Blue from aqueous solution by microwave modified graphene oxide explored for various experimental variables such as pH, concentration of dyes, adsorbent dose, contact time, and temperature. Experiments were carried out to determine the % percentage removal of Methyle Blue along with determination of equlibrium concentration and equlibriun adsorption capacity of microwave modified GO. In this study, it was found that adsorptive removal of Methylene Blue by graphene oxide and microwave modified graphene oxide follows Langmuir isotherm. The % removal of GO and microwave modified GO is 93.15% and 99.15%, respectively. The present work describes novel, eco-friendly as well as cost effective method for modification of graphene oxide by microwave irradiation in aqueous suspension without any chemical agent or reaction enhancer using domestic microwave instrument. It results in improvement of adsorptive capacity of graphene oxide for cationic dye removal. Further, microwave treatment of GO can be considered as a potential treatment method for adsorptive removal of dyes for treatment of industrial effluents.