Determination of the Heat of Adsorption from Solution from Equilibrium Concentration Measurements as a Function of the Temperature and Comparison with Direct Calorimetric Measurements


(*) Corresponding author


Authors' affiliations


DOI's assignment:
the author of the article can submit here a request for assignment of a DOI number to this resource!
Cost of the service: euros 10,00 (for a DOI)

Abstract


A method for the determination of the heat of adsorption from solution of a substance,  , from measurements of the equilibrium concentration of the substance remaining in solution as a function of the temperature is presented and compared with the direct measurement of the heat of adsorption using a state-of-the art heat conduction microcalorimeter for the system phenol in aqueous solution and an activated carbon surface. Equilibrium considerations are employed similar to those used to calculate the so-called isosteric heat of adsorption from the slope of the equilibrium pressure vs. the temperature at constant adsorption but in a way simpler than this method which requires recording the pressure as a function of the coverage, ξ, at several temperatures while the present method gives directly the heat of adsorption from the single slope of the equilibrium concentration vs. the temperature at constant pressure. The transfer of moles of solute from the solution to the carbon surface obeys Nernst’s distribution law with an equilibrium constant which depends only on the temperature and pressure. Hence, the quantities obtained from the equilibrium condition are standard functions. The values obtained for the heat of adsorption of phenol by this method are typical of those found for mild physical adsorption. Heats of adsorption are important to characterize porous carbon surfaces and for the study of intermolecular interactions in condensed phases
Copyright © 2010 Praise Worthy Prize - All rights reserved.

Keywords


Heat of Adsorption from Solution; Heat Conduction Microcalorimeter; Aqueous-Phase Adsorption of Phenol by Active Carbon; Nernst’s Distribution Law; Regular Solution; Intermolecular Interactions

Full Text:

PDF


References


W. Rudzinski and D. H. Everett, Adsorption of gases on heterogeneous surfaces, Academic Press, London, 1992.

J. S. Mattson and H. B. Mark, Jr. Activated Carbon: Surface Chemistry and Adsorption from Solution, Marcel Dekker, New York, 1971.

C. Hsieh and T. Hsisheng, J. Colloid Interface Sci. 230, 171 (2000).

H. F. Stoeckli, V. M. López-Ramón and C. Moreno-Castilla, Langmuir 17, 3301 (2001).

I. Prigogine and R. Defay, Chemical Thermodynamics, Longmans, Green & Co. Ltd., London, 1954.

R. Defay and I. Prigogine, Surface Tension and Adsorption, Longmans, Green & Co. Ltd., London, 1966.

D. P. Shoemaker, C. W. Garland and J. I. Steinfeld, Experiments in Physical Chemistry, 3rd ed., McGraw-Hill Book Company, New York, 1974.

L. Giraldo, J. C. Moreno and J. I. Huertas, Instrumentation Science & Technology 30, 177 (2002).

V. García-Cuello, J.C.Moreno-Piraján, L. Giraldo-Gutierréz, K. Sapag, G. Zgrablich, Micropor. Mesopor. Mater. doi 10.1016 ,in press 2008.

V. García-Cuello, J. C.Moreno-Piraján, L. Giraldo-Gutierréz, K. Sapag, G. Zgrablich, Research Letters in Physical Chemistry, doi 10.1155 2008 published in 2008.

L. F. Navarrete, L. Giraldo, Juan Carlos Moreno, Rev. Col. Quim. 35, 2006.

J. C. Moreno-Piraján, L .F. Navarrete, L. Giraldo, V. García-Cuello, Inf. Tecn., 18, 2007.

Liliana Giraldo, Vanessa García, Juan Carlos Moreno, Rev. Ing. 27,2008.

I. Langmuir, Trans. Faraday Soc. 17, 621 (1921).

R. Qadeer and A. H. Rehan, Turk. J. Chem. 26, 357 (2002).

W. J. Weber, Jr. and J. C. Morris, J. Sanit. Eng. Div. 90, 79 (1964).

J. C. Moreno-Piraján, L. F. Navarrete, L. Giraldo,V. García, Inf. Tec. 18, 71 (2007).

D. Ramirez, P. D.Sullivan, M. J.Rood, K. J. Hay, J. Env.Eng. 130, 231 (2004).

A. Das, S. K. Durlubh, Energy, 20, 821 (1998).

M. Ahmaruzzaman, D. K. Sharma, J. Coll. Int. Sc. 287, 14 (2005).

A. Akgerman, M. Zardkoohi, J. Chem. Eng. Data, 41, 185 (1996).

F. Haghseresht, G. Q. Lu, Energy & Fuels, 12, 1100 (1998).

Z. Aksu, J. Yener, Waste Management, 21, 695 (2001).


Refbacks

  • There are currently no refbacks.


Please send any question about this web site to info@praiseworthyprize.com
Copyright © 2005-2024 Praise Worthy Prize