Determination of the Polar and Total Surface Energy Distributions of Particulates by Inverse Gas Chromatography

Langmuir ◽  
2011 ◽  
Vol 27 (2) ◽  
pp. 521-523 ◽  
Author(s):  
Shyamal C. Das ◽  
Ian Larson ◽  
David A. V. Morton ◽  
Peter J. Stewart
Keyword(s):  
Gas Chromatography ◽  
Surface Energy ◽  
Inverse Gas Chromatography ◽  
Total Surface Energy ◽  
Energy Distributions

The determination of the surface energy of conducting polymers by inverse gas chromatography at infinite dilution

1999 ◽  
Vol 104 (1) ◽  
pp. 51-59 ◽  
Author(s):  
Mohamed M Chehimi ◽  
Marie-Laure Abel ◽  
Christian Perruchot ◽  
Michel Delamar ◽  
Stuart F Lascelles ◽  
...  
Keyword(s):  
Gas Chromatography ◽  
Surface Energy ◽  
Conducting Polymers ◽  
Infinite Dilution ◽  
Inverse Gas Chromatography

scholarly journals New approach to determine the surface and interface thermodynamic properties of H-β-zeolite/rhodium catalysts by inverse gas chromatography at infinite dilution

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Tayssir Hamieh ◽  
Ali Ali Ahmad ◽  
Thibault Roques-Carmes ◽  
Joumana Toufaily
Keyword(s):  
Gas Chromatography ◽  
Linear Regression ◽  
Surface Energy ◽  
Infinite Dilution ◽  
Inverse Gas Chromatography ◽  
Acid Base ◽  
Dispersive Component ◽  
Β Zeolite ◽  
Gamma S

AbstractThe thermodynamic surface properties and Lewis acid–base constants of H-β-zeolite supported rhodium catalysts were determined by using the inverse gas chromatography technique at infinite dilution. The effect of the temperature and the rhodium percentage supported by zeolite on the acid base properties in Lewis terms of the various catalysts were studied. The dispersive component of the surface energy of Rh/H-β-zeolite was calculated by using both the Dorris and Gray method and the straight-line method. We highlighted the role of the surface areas of n-alkanes on the determination of the surface energy of catalysts. To this aim various molecular models of n-alkanes were tested, namely Kiselev, cylindrical, Van der Waals, Redlich–Kwong, geometric and spherical models. An important deviation in the values of the dispersive component of the surface energy $${\gamma }_{s}^{d}$$ γ s d determined by the classical and new methods was emphasized. A non-linear dependency of $${\gamma }_{s}^{d}$$ γ s d with the specific surface area of catalysts was highlighted showing a local maximum at 1%Rh. The study of RTlnVn and the specific free energy ∆Gsp(T) of n-alkanes and polar solvents adsorbed on the various catalysts revealed the important change in the acid properties of catalysts with both the temperature and the rhodium percentage. The results proved strong amphoteric behavior of all catalysts of the rhodium supported by H-β-zeolite that actively react with the amphoteric solvents (methanol, acetone, tri-CE and tetra-CE), acid (chloroform) and base (ether) molecules. It was shown that the Guttmann method generally used to determine the acid base constants KA and KD revealed some irregularities with a linear regression coefficient not very satisfactory. The accurate determination of the acid–base constants KA, KD and K of the various catalysts was obtained by applying Hamieh’s model (linear regression coefficients approaching r2 ≈ 1.000). It was proved that all acid base constants determined by this model strongly depends on the rhodium percentage and the specific surface area of the catalysts.

Determination of surface heterogeneity of d-mannitol by sessile drop contact angle and finite concentration inverse gas chromatography

2010 ◽  
Vol 387 (1-2) ◽  
pp. 79-86 ◽  
Author(s):  
Raimundo Ho ◽  
Steven J. Hinder ◽  
John F. Watts ◽  
Sarah E. Dilworth ◽  
Daryl R. Williams ◽  
...  
Keyword(s):  
Gas Chromatography ◽  
Contact Angle ◽  
Inverse Gas Chromatography ◽  
Sessile Drop ◽  
Surface Heterogeneity ◽  
Finite Concentration
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