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Title: Sorption-desorption kinetics for powdered and non-powered coal

Abstract

Diffusion through macro- and meso-pores with the subsequent filling of open micropores is a relatively fast process and the manometric measurements with fifteen minute pressure stabilization steps provide a good estimate of excess (ad)sorption. This can be followed by a much slower processes of the penetrant diffusion into the macromolecular network, accompanied by its structural relaxation, with or without free volume changes. The “free volume” effect is a change of the sample’s excluded volume because of the penetrant molecules mixing within the formerly excluded volume of the network or because of contraction (either reversible or semi-permanent) due to external pressure. If the resulting swelling of the sample leads to the mixture’s volume equal to the sum of the initial volumes of the components, there is no apparent change to the void volume and no pressure relaxation is observed (b). On the other hand, if the external forces (either macroscopic pressure or microscopic molecular interaction forces) change the excluded volume of the network (its density), without exchange of the sorbent molecules between the sample and the free fluid phase, such change causes a corresponding change in the void volume, which constitutes a pure free volume effect (c). In this case, nomore » post-decompression exodus of the sorbent out of the sample is observed. As a special case, we consider an incorporation of the penetrant molecules into the network without any change in the volume of the mixture (d), though mathematically this can be written as a superposition of the previous two cases« less

Authors:
;
Publication Date:
Research Org.:
National Energy Technology Laboratory (NETL), Pittsburgh, PA, and Morgantown, WV
Sponsoring Org.:
USDOE - Office of Fossil Energy (FE)
OSTI Identifier:
915426
Report Number(s):
DOE/NETL-IR-2007-141
TRN: US200817%%510
DOE Contract Number:
None cited
Resource Type:
Conference
Resource Relation:
Conference: Sixth Annual Conference on Carbon Capture & Sequestration, Pittsburgh, PA, May 7-10, 2007; Related Information: Poster is only publication.
Country of Publication:
United States
Language:
English
Subject:
01 COAL, LIGNITE, AND PEAT; CARBON; COAL; CONTRACTION; DIFFUSION; KINETICS; MIXTURES; RELAXATION; STABILIZATION; SWELLING

Citation Formats

Romanov, V., and Soong, Y. Sorption-desorption kinetics for powdered and non-powered coal. United States: N. p., 2007. Web.
Romanov, V., & Soong, Y. Sorption-desorption kinetics for powdered and non-powered coal. United States.
Romanov, V., and Soong, Y. Tue . "Sorption-desorption kinetics for powdered and non-powered coal". United States. doi:. https://www.osti.gov/servlets/purl/915426.
@article{osti_915426,
title = {Sorption-desorption kinetics for powdered and non-powered coal},
author = {Romanov, V. and Soong, Y.},
abstractNote = {Diffusion through macro- and meso-pores with the subsequent filling of open micropores is a relatively fast process and the manometric measurements with fifteen minute pressure stabilization steps provide a good estimate of excess (ad)sorption. This can be followed by a much slower processes of the penetrant diffusion into the macromolecular network, accompanied by its structural relaxation, with or without free volume changes. The “free volume” effect is a change of the sample’s excluded volume because of the penetrant molecules mixing within the formerly excluded volume of the network or because of contraction (either reversible or semi-permanent) due to external pressure. If the resulting swelling of the sample leads to the mixture’s volume equal to the sum of the initial volumes of the components, there is no apparent change to the void volume and no pressure relaxation is observed (b). On the other hand, if the external forces (either macroscopic pressure or microscopic molecular interaction forces) change the excluded volume of the network (its density), without exchange of the sorbent molecules between the sample and the free fluid phase, such change causes a corresponding change in the void volume, which constitutes a pure free volume effect (c). In this case, no post-decompression exodus of the sorbent out of the sample is observed. As a special case, we consider an incorporation of the penetrant molecules into the network without any change in the volume of the mixture (d), though mathematically this can be written as a superposition of the previous two cases},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue May 01 00:00:00 EDT 2007},
month = {Tue May 01 00:00:00 EDT 2007}
}

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