| Autor: |
Weerasooriya R; Institut für Geologie und Mineralogie, Lehrstuhul für Angewandte Geologie, Friedrich-Alexander Universität, Schlossgarten 5, Nürnberg, Erlangen D-91054, Germany. rweerasooriya@hotmail.com, Makehelwala M, Miedaner MM, Tobschall HJ |
| Jazyk: |
angličtina |
| Zdroj: |
Journal of colloid and interface science [J Colloid Interface Sci] 2006 May 01; Vol. 297 (1), pp. 31-7. Date of Electronic Publication: 2005 Dec 27. |
| DOI: |
10.1016/j.jcis.2005.10.009 |
| Abstrakt: |
Thermodynamic parameters of the activation state for phenol and three monochlorophenol (MCP) isomer-pyrite complexes, i.e., MCP isomers used were 2-chlorophenol (2-CP), 3-chlorophenol (3-CP), 4-chlorophenol (4-CP), have been derived from the temperature-dependent kinetic data. Both the initial rate and adsorption density values increased in the order phenol < 2-CP < 3-CP < 4-CP. This suggests that the presence of chlorine substituent on the aromatic ring results in enhanced CP adsorption on pyrite. The activation energy (E(a)), Gibbs free energy (deltaG#), entropy (deltaS#), and enthalpy (deltaH#) of the activation stage for MCP adsorption on pyrite were calculated by Arrhenius and Eyring models. Always deltaS# values approximate to zero and -TdeltaS# values are positive, which indicates that the activation state of MCP adsorption process is entropy-controlled, and the observed linear dependence of deltaH# on -TdeltaS# signals an entropy-enthalpy compensation effect of the MCP adsorption process. The gammaMCP data were quantified well both by 1 - pK diffused double layer (1 - pK DLM) and Langmuir models. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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