ISSN:
1612-1112
Keywords:
Inverse gas chromatography
;
Calcium carbonate
;
Stearic acid modified calcium carbonate
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Summary The interaction of n-alkanes with stearyl chains chemically fixed on the surface of calcite particles is investigated using inverse gas chromatography. Free enthalpy, enthalpy, entropy of adsorption and dispersive component of the surface free energy are determined. Untreated and stearic acid treated calcites have comparable affinities for the alkanes. However, the differences in adsorption entropies point to different interaction mechanisms: gas-solid adsorption for the untreated calcite and gasliquid interactions for the modified sample. Furthermore, for long chains probes, having more than 8 carbon atoms, the loss in entropy is smaller than for shorter chains. Possibly, long chains are only partially inserted in between the stearyl grafts, thus keeping a higher degree of freedom.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02262085
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