Accession Number : AD0733456

Title :   Adsorption Isotherms and Equations of State of Insoluble Vapors at the Water-Gas Interface as Studied by Gas Chromatography.

Descriptive Note : Technical rept.,

Corporate Author : NORTHEASTERN UNIV BOSTON MASS DEPT OF CHEMISTRY

Personal Author(s) : Karger,Barry L. ; King,Jerry W. ; Chatterjee,Amiya

Report Date : NOV 1971

Pagination or Media Count : 35

Abstract : In continuation of previous work on the study of water at interfaces by gas chromatography, the gas-liquid interfacial adsorption isotherms of six insoluble vapors (three n-alkanes and three branched alkanes) have been determined in the range of 4000 sq A /molecule to 500 sq A/ molecule. From these isotherms, isosteric heats of adsorption have been derived, and it has been shown that over the whole concentration range examined the isosteric heat of adsorption is equal to or less than the heat of liquefaction. This points to the fact that water is a low energy surface for hydrocarbons. The free energy of adsorption and the entropy of adsorption at constant surface coverage have been also calculated. Equations of state have been determined. Finally, calculations of thickness of the surface films indicate that the hydrocarbons can be considered to lie flat on the water surface in most cases over the whole concentration range studied. (Author)

Descriptors :   (*HYDROCARBONS, *ADSORPTION), (*WATER, ADSORPTION), GAS CHROMATOGRAPHY, INTERFACES, SOLUBILITY, FREE ENERGY, MOLECULAR STRUCTURE, THERMODYNAMICS, EQUATIONS OF STATE

Subject Categories : Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE