Effects of surface chemistry on the porous structure of coal. Technical progress report, September 1994--October 1995

Abstract

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, 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 completed for four coals, and N{sub 2} and C0{sub 2} adsorption isotherms with surface area measurement have been completed for three coals. A microporous carbon has been subjected to one oxygen chemisorption/desorption cycle and examined by {sup 129}Xe NMR.