title: Benzene carboxylic acid derivatized graphene oxide nanosheets on natural zeolites as effective adsorbents for cationic dye removal.
abstract: Graphene oxide (GO) nanosheets were grafted to acid-treated natural clinoptilolite-rich zeolite powders followed by a coupling reaction with a diazonium salt (4-carboxybenzenediazoniumtetrafluoroborate) to the GO surface. Raman spectroscopy, Fourier transform infrared (FTIR) spectroscopy, and thermogravimetric analysis (TGA) revealed successful grafting of GO nanosheets onto the zeolite surface. The application of the adsorbents for the adsorption of rhodamine B from aqueous solutions was then demonstrated. After reaching adsorption equilibrium the maximum adsorption capacities were shown to be 50.25, 55.56 and 67.56 mg g(-1) for pristine natural zeolite, GO grafted zeolite (GO-zeolite) and benzene carboxylic acid derivatized GO-zeolite powders, respectively. The adsorption behavior was fitted to a Langmuir isotherm and shown to follow a pseudo-second-order reaction model. Further, a relationship between surface functional groups, pH and adsorption efficiency was established. Results indicate that benzene carboxylic acid derivatized GO-zeolite powders are environmentally favorable adsorbents for the removal of cationic dyes from aqueous solutions.
authors.affiliation: Flinders Centre for Nanoscale Science & Technology, School of Chemical and Physical Sciences, Flinders University, Sturt Road, Bedford Park, Adelaide, SA 5042, Australia.
authors.forename: Yang
authors.initials: Y
authors.lastname: Yu
authors.forename: Bandaru N
authors.initials: BN
authors.lastname: Murthy
authors.forename: Joseph G
authors.initials: JG
authors.lastname: Shapter
authors.forename: Kristina T
authors.initials: KT
authors.lastname: Constantopoulos
authors.forename: Nicolas H
authors.initials: NH
authors.lastname: Voelcker
authors.forename: Amanda V
authors.initials: AV
authors.lastname: Ellis
mesh_terms: D000143:Acids / Q000737:chemistry; D000327:Adsorption; D001554:Benzene / Q000737:chemistry*; D002264:Carboxylic Acids / Q000737:chemistry*; D002412:Cations; D004396:Coloring Agents / Q000032:analysis*; D003979:Diazonium Compounds / Q000737:chemistry; D006108:Graphite / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste; D007700:Kinetics; D053758:Nanoparticles / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D012235:Rhodamines / Q000032:analysis*; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D055672:Static Electricity; D013499:Surface Properties; D013818:Thermogravimetry; D014874:Water Pollutants, Chemical / Q000032:analysis*; D018508:Water Purification / Q000379:methods; D017641:Zeolites / Q000737:chemistry*
chemical_list: D000143:Acids; D002264:Carboxylic Acids; D002412:Cations; D004396:Coloring Agents; D003979:Diazonium Compounds; D007220:Industrial Waste; D010087:Oxides; D012235:Rhodamines; D014874:Water Pollutants, Chemical; D017641:Zeolites; D006108:Graphite; D001554:Benzene; C029773:rhodamine B
keywords: Adsorption kinetics; Diazonium salts; Graphene oxide; Natural zeolites; Rhodamine B