Asphaltene adsorption onto an iron surface: combined near-infrared (NIR), raman, and AFM study of the kinetics, thermodynamics, and layer structure
Publication details: ene./feb. 2011Description: 8 p. ; 189-196 In: Energy & fuels 25Summary: Transcripción del resumen del autor. A combination of near-infrared (NIR) spectroscopy, Raman microscopy, and atomic force microscopy (AFM) was used to analyze the adsorption behavior of petroleum macromolecules (asphaltenes) on an iron (Fe) surface. A partial least-squares (PLS/PLSR) regression method was used for determining the concentration from NIR spectroscopic data. A Langmuir model was used to fit the experimental data. Effective kinetic and thermodynamic parameters (Gibbs energy of adsorption, adsorption/desorption rate constant, maximal adsorbed mass density) of asphaltenes adsorbed from benzene solution were evaluated: the maximum adsorbed mass density (Gmax) was found to be 4.90 ± 0.07 mg m-2; the adsorption constant (K) was found to be 0.084 ± 0.007 L mg-1; and a value of 34.3 ± 0.2 kJ mol-1 was calculated for the effective Gibbs energy of absorption (- Gads). The structure of the adsorbed layer was also analyzed by AFM. Asphaltenes were found to form aggregates on Fe surface with an average size of a few hundred nanometers. The notion of a nonuniform distribution of crude oil macromolecules adsorbed on metal surfaces was experimentally confirmed.| Current library | Status | Barcode | |
|---|---|---|---|
| Biblioteca Alejandro Angel Bulgheroni | Not for loan | 200052408 |
Transcripción del resumen del autor. A combination of near-infrared (NIR) spectroscopy, Raman microscopy, and atomic force microscopy (AFM) was used to analyze the adsorption behavior of petroleum macromolecules (asphaltenes) on an iron (Fe) surface. A partial least-squares (PLS/PLSR) regression method was used for determining the concentration from NIR spectroscopic data. A Langmuir model was used to fit the experimental data. Effective kinetic and thermodynamic parameters (Gibbs energy of adsorption, adsorption/desorption rate constant, maximal adsorbed mass density) of asphaltenes adsorbed from benzene solution were evaluated: the maximum adsorbed mass density (Gmax) was found to be 4.90 ± 0.07 mg m-2; the adsorption constant (K) was found to be 0.084 ± 0.007 L mg-1; and a value of 34.3 ± 0.2 kJ mol-1 was calculated for the effective Gibbs energy of absorption (- Gads). The structure of the adsorbed layer was also analyzed by AFM. Asphaltenes were found to form aggregates on Fe surface with an average size of a few hundred nanometers. The notion of a nonuniform distribution of crude oil macromolecules adsorbed on metal surfaces was experimentally confirmed.
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