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Title: Coal surface structure and thermodynamics. Final report

Abstract

Coals surfaces were studied using static surface adsorption measurements, low angle x-ray scattering (LAXS), inverse gas chromatography (IGC) and a new {sup 13}C NMR relaxation technique. A comparison of surface areas determined by hydrocarbon gas adsorption and LAXS led to the twin conclusions that the hydrocarbons had to diffuse through the solid to reach isolated pores and that the coal pores do not form interconnected networks, but are largely isolated. This conclusion was confirmed when IGC data for small hydrocarbons showed no discontinuities in their size dependence as usually observed with porous solids. IGC is capable of providing adsorption thermodynamics of gases on coal surfaces. The interactions of non-polar molecules and coal surfaces are directly proportioned to the gas molecular polarizability. For bases, the adsorption enthalpy is equal to the polarizability interaction plus the heat of hydrogen bond formation with phenol. Amphoteric molecules have more complex interactions. Mineral matter can have highly specific effects on surface interactions, but with most of the molecules studied is not an important factor.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Lehigh Univ., Bethlehem, PA (United States). Dept. of Chemistry
Sponsoring Org.:
USDOE, Washington, DC (United States)
OSTI Identifier:
49114
Report Number(s):
DOE/PC/89757-T1
ON: DE95005301
DOE Contract Number:
AC22-89PC89757
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: May 1994
Country of Publication:
United States
Language:
English
Subject:
01 COAL, LIGNITE, AND PEAT; COAL; SURFACE PROPERTIES; NUCLEAR MAGNETIC RESONANCE; SCATTERING; SURFACE AREA; CORRELATIONS; PROGRESS REPORT; POROSITY; SPECTRA

Citation Formats

Larsen, J.W., Wernett, P.C., Glass, A.S., Quay, D., and Roberts, J.. Coal surface structure and thermodynamics. Final report. United States: N. p., 1994. Web. doi:10.2172/49114.
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Larsen, J.W., Wernett, P.C., Glass, A.S., Quay, D., & Roberts, J.. Coal surface structure and thermodynamics. Final report. United States. doi:10.2172/49114.
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Larsen, J.W., Wernett, P.C., Glass, A.S., Quay, D., and Roberts, J.. Sun . "Coal surface structure and thermodynamics. Final report". United States. doi:10.2172/49114. https://www.osti.gov/servlets/purl/49114.
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@article{osti_49114,
title = {Coal surface structure and thermodynamics. Final report},
author = {Larsen, J.W. and Wernett, P.C. and Glass, A.S. and Quay, D. and Roberts, J.},
abstractNote = {Coals surfaces were studied using static surface adsorption measurements, low angle x-ray scattering (LAXS), inverse gas chromatography (IGC) and a new {sup 13}C NMR relaxation technique. A comparison of surface areas determined by hydrocarbon gas adsorption and LAXS led to the twin conclusions that the hydrocarbons had to diffuse through the solid to reach isolated pores and that the coal pores do not form interconnected networks, but are largely isolated. This conclusion was confirmed when IGC data for small hydrocarbons showed no discontinuities in their size dependence as usually observed with porous solids. IGC is capable of providing adsorption thermodynamics of gases on coal surfaces. The interactions of non-polar molecules and coal surfaces are directly proportioned to the gas molecular polarizability. For bases, the adsorption enthalpy is equal to the polarizability interaction plus the heat of hydrogen bond formation with phenol. Amphoteric molecules have more complex interactions. Mineral matter can have highly specific effects on surface interactions, but with most of the molecules studied is not an important factor.},
doi = {10.2172/49114},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sun May 01 00:00:00 EDT 1994},
month = {Sun May 01 00:00:00 EDT 1994}
}
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Technical Report:
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DOI:  10.2172/49114
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