Artículo
Abstract:
An analytical isotherm equation that can be applied to water vapor-biopolymer systems, was developed. The model describes the multilayer adsorption on fractal surfaces with energetic interactions adsorbate-adsorbate (measure in terms of free energy) different from that of bulk water. Assuming explicit mathematical functionalities for the variation of the free energy with the number of adsorbed layers, it is possible to evaluate the effect of the adsorbate-adsorbate interactions on the adsorption capacity of solids of high degree of surface irregularity. For those surfaces with relatively low degree of irregularity (D values slightly larger than 2), it results that the free energy variation with the layer number in the multilayer region affects considerably the sorption capacity of the adsorbent, even for water activities lower than those corresponding to the monolayer moisture content. This effect becomes less marked as the fractal dimension increases (D approaching to 3), being relevant for water activities much larger than those corresponding to the monolayer value, only. The isotherm was tested, using published experimental equilibrium data of various biopolymers. An analytical isotherm equation that can be applied to water vapor-biopolymer systems, was developed. The model describes the multilayer adsorption on fractal surfaces with energetic interactions adsorbate-adsorbate (measure in terms of free energy) different from that of bulk water. Assuming explicit mathematical functionalities for the variation of the free energy with the number of adsorbed layers, it is possible to evaluate the effect of the adsorbate-adsorbate interactions on the adsorption capacity of solids of high degree of surface irregularity. For those surfaces with relatively low degree of irregularity (D values slightly larger than 2), it results that the free energy variation with the layer number in the multilayer region affects considerably the sorption capacity of the adsorbent, even for water activities lower than those corresponding to the monolayer moisture content. This effect becomes less marked as the fractal dimension increases (D approaching to 3), being relevant for water activities much larger than those corresponding to the monolayer value, only. The isotherm was tested, using published experimental equilibrium data of various biopolymers.
Registro:
| Documento: | Artículo |
| Título: | Multilayer adsorption on fractal surfaces: Effect of the adsorbate-adsorbate interactions on the sorptional equilibrium |
| Autor: | Aguerre, R.J.; Tolaba, M.P.; Suárez, C. |
| Ciudad: | New York |
| Filiación: | Departamento de Tecnología, Universidad Nacional de Luján, Cruces Rutas 5 y 7, C.C. 221, (6700) Luján, Argentina Departamento de Industrias, Fac. de Ciencias Exactas y Naturales, Ciudad Universitaria, (1428) Buenos Aires, Argentina |
| Palabras clave: | Adsorbate-adsorbate interactions on fractal surfaces; Fractal isotherm; Fractality of biopolymers; Adsorption isotherms; Biopolymers; Multilayers; Numerical methods; Phase equilibria; Sorption; Surface phenomena; Water; Adsorbate adsorbate interactions; Fractal dimensions; Fractal surfaces; Sorptional equilibrium; Adsorption; Adsorption; Drying; fractal analysis |
| Año: | 1999 |
| Volumen: | 17 |
| Número: | 4-5 |
| Página de inicio: | 869 |
| Página de fin: | 881 |
| DOI: | http://dx.doi.org/10.1080/07373939908917575 |
| Título revista: | Drying Technology |
| Título revista abreviado: | Dry. Technol. |
| ISSN: | 07373937 |
| CODEN: | DRTED |
| Registro: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_07373937_v17_n4-5_p869_Aguerre |
Referencias:
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Citas:
---------- APA ----------
Aguerre, R.J., Tolaba, M.P. & Suárez, C. (1999) . Multilayer adsorption on fractal surfaces: Effect of the adsorbate-adsorbate interactions on the sorptional equilibrium. Drying Technology, 17(4-5), 869-881.http://dx.doi.org/10.1080/07373939908917575
---------- CHICAGO ----------
Aguerre, R.J., Tolaba, M.P., Suárez, C. "Multilayer adsorption on fractal surfaces: Effect of the adsorbate-adsorbate interactions on the sorptional equilibrium" . Drying Technology 17, no. 4-5 (1999) : 869-881.http://dx.doi.org/10.1080/07373939908917575
---------- MLA ----------
Aguerre, R.J., Tolaba, M.P., Suárez, C. "Multilayer adsorption on fractal surfaces: Effect of the adsorbate-adsorbate interactions on the sorptional equilibrium" . Drying Technology, vol. 17, no. 4-5, 1999, pp. 869-881.http://dx.doi.org/10.1080/07373939908917575
---------- VANCOUVER ----------
Aguerre, R.J., Tolaba, M.P., Suárez, C. Multilayer adsorption on fractal surfaces: Effect of the adsorbate-adsorbate interactions on the sorptional equilibrium. Dry. Technol. 1999;17(4-5):869-881.http://dx.doi.org/10.1080/07373939908917575
