| Autor: |
R. A. Fonseca-Correa, M. J. Bastidas-Barranco, L. Giraldo, J. C. Moreno-Piraján |
| Jazyk: |
angličtina |
| Rok vydání: |
2017 |
| Předmět: |
|
| Zdroj: |
Carbon: Science and Technology, Vol 9, Iss 1, Pp 47-64 (2017) |
| Druh dokumentu: |
article |
| ISSN: |
0974-0546 |
| Popis: |
The heterogeneity and hydrophilicity of a series of aerogels were studied using adsorption calorimetry with molecules of different polarity. Four samples of carbon aerogel were synthesized with different resorcinol/catalytic (R/C) relations: 100, 200, 800 and 1500. The isotherms of N2 at -196 ◦C were determined and from these were calculated the textural parameters using the Dubinin–Astakhov (DA), Barret–Joyner–Halenda (BJH), Non-Local Density Functional Theory (NLDFT) and Quenched Solid Density Functional Theory (QSDFT) models. The adsorption isotherms of polar and non-polar molecules: benzene, hexane, methane, methanol and methyl-ethyl-ketone (MEK) were determined, as well as the differential adsorption enthalpies of these on the aerogel. The results show that the aerogels samples at low R/C have a fundamental development of micropores and at high R/C values present an additional development of mesoporosity. Adsorption isotherms of polar and non-polar molecules were adjusted to the Langmuir–Sips model and In-homogenous DA equation, respectively. Adsorption calorimetry shows that the carbon aerogels at these relations present heterogeneous surfaces that are essentially hydrophilic. |
| Databáze: |
Directory of Open Access Journals |
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