Open AccessEffects of surface chemistry on the porous structure of coal. Quarterly technical progress report, October 1995--December 1995
Author(s) -
Stasia A. Anderson,
Ljubiša R. Radović,
P.G. Hatcher
Publication year - 1995
Language(s) - English
Resource type - Reports
DOI - 10.2172/219172
Subject(s) - microporous material , coal , porosity , chemisorption , adsorption , chemistry , nmr spectra database , carbon fibers , mineralogy , analytical chemistry (journal) , spectral line , materials science , organic chemistry , composite material , physics , astronomy , composite number
The primary objective of this work is to use {sup 129}Xe NMR to characterize the microporous structure of coals. As an aide in this characterization, which is by no means straightforward, another objective is to combine this technique with volumetric adsorption techniques and track the effect of controlled opening of the micropores in a microporous carbon by oxygen chemisorption/desorption. The primary goal of the NMR work is to measure the micropore sizes in coal; more broadly, it is to better tailor the {sup 129}Xe NMR method for use with coal, and to investigate other ways it may be used to describe pore structure in coal, with emphasis on determining whether micropores in coal are connected or isolated. In terms of the primary objectives of the project, the {sup 129}Xe NMR spectra with pressure variation have been obtained for two more coals, completing this task for the sample set of six coals. In terms of the broad objectives of the project, examination of the influence on the xenon signal of packing the powdered coal has been undertaken. These data are of potential value for the determination of whether the porosity is open or closed. Results of powder density and related experiments will be used in the final interpretation of our current data, including the determination of whether, in the NMR of loose powdered, the chemical shift is indicative of the ``true`` gas-solid interaction