title: Multilayer adsorption on fractal surfaces.
abstract: Multilayer adsorption is often observed in liquid chromatography. The most frequently employed model for multilayer adsorption is the BET isotherm equation. In this study we introduce an interpretation of multilayer adsorption measured on liquid chromatographic stationary phases based on the fractal theory. The fractal BET isotherm model was successfully used to determine the apparent fractal dimension of the adsorbent surface. The nonlinear fitting of the fractal BET equation gives us the estimation of the adsorption equilibrium constants and the monolayer saturation capacity of the adsorbent as well. In our experiments, aniline and proline were used as test molecules on reversed phase and normal phase columns, respectively. Our results suggest an apparent fractal dimension 2.88-2.99 in the case of reversed phase adsorbents, in the contrast with a bare silica column with a fractal dimension of 2.54.
authors: Department of Analytical and Environmental Chemistry and Szentágothai Research Center, University of Pécs, Ifjúság útja 6, H-7624 Pécs, Hungary.
authors: Péter
authors: P
authors: Vajda
authors: Department of Analytical and Environmental Chemistry and Szentágothai Research Center, University of Pécs, Ifjúság útja 6, H-7624 Pécs, Hungary; MTA-PTE Molecular Interactions in Separation Science Research Group, Ifjúság útja 6, H-7624 Pécs, Hungary. Electronic address: felinger@ttk.pte.hu.
authors: Attila
authors: A
authors: Felinger
mesh_terms: D000327:Adsorption; D000814:Aniline Compounds / Q000032:analysis; D002853:Chromatography, Liquid / Q000379:methods; D017709:Fractals; D017711:Nonlinear Dynamics; D011392:Proline / Q000032:analysis; D013499:Surface Properties
chemical_list: D000814:Aniline Compounds; D011392:Proline; C023650:aniline