Vieira, Eduardo G. [UNESP]Soares, Isaac V. [UNESP]Dias Filho, Newton L. [UNESP]da Silva, Niléia C. [UNESP]Garcia, Edemir F. [UNESP]Bastos, Andréa C. [UNESP]Perujo, Sérgio D. [UNESP]Ferreira, Tamires T. [UNESP]Rosa, André H. [UNESP]Fraceto, Leonardo F. [UNESP]2014-05-272014-05-272013-02-01Journal of Colloid and Interface Science, v. 391, n. 1, p. 116-124, 2013.0021-97971095-7103http://hdl.handle.net/11449/74470A silica surface chemically modified with [3-(2,2'-dipyridylamine) propyl] groups was prepared, characterized, and evaluated for its metal ion preconcentration in fuel ethanol. To our knowledge, we are the first authors who have reported the present modification on silica gel surface. The material was characterized using infrared spectra, scanning electronic microscopy, and 13C and 29Si solid-state NMR spectra. Batch and column experiments were conducted to investigate for metal ion removal from fuel ethanol. The results showed that the Langmuir model describes the sorption equilibrium data of the metal ions in a satisfactory way. From the Langmuir isotherms, the following maximum adsorption capacities (in mmolg -1) were determined: 1.81 for Fe(III), 1.75 for Cr(III), 1.30 for Cu(II), 1.25 for Co(II), 1.15 for Pb(II), 0.95 for Ni(II), and 0.87 for Zn(II). Thermodynamic functions, the change of free energy (ΔG), enthalpy (ΔH), and entropy (ΔS) showed that the adsorption of metal ions onto Si-Pr-DPA was feasible, spontaneous, and endothermic. The sorption-desorption of the metal ions made possible the development of a preconcentration and quantification method of metal ions in fuel ethanol. © 2012 Elsevier Inc.116-124engAdsorptionDetermination methodEthanol fuelPreconcentrationThermodynamic parametersAdsorption capacitiesBonded silicaChemically modifiedColumn experimentsDipyridylamineFuel ethanolInfrared spectrumLangmuir isothermLangmuir modelsMetal ion removalPre-concentrationQuantification methodsScanning electronic microscopySilica gel surfacesSilica surfaceSolid state NMRSorption equilibriaThermodynamic functionsThermodynamic parameterChromium compoundsDesorptionEthanol fuelsIron compoundsLeadNuclear magnetic resonance spectroscopySilicaSilica gelSiliconZinc compoundsMetal ionsalcoholalkane derivativecarbon 13chromiumcobaltcopperironleadmetal ionnickelsilicon dioxidezincadsorptionchemical bondchemical modelchemical modificationconcentration (parameters)desorptionenergyenthalpyentropyfeasibility studyinfrared spectrometrynuclear magnetic resonance spectroscopypriority journalquantitative analysisscanning electron microscopesynthesisthermodynamicsArtigo10.1016/j.jcis.2012.08.073WOS:000312039000016Acesso restrito2-s2.0-848686539250000-0002-2042-018X