IN SITU STUDIES OF COAL PRESSURIZED WITH CO2 BY SMALL ANGLE AND HIGH ENERGY, WIDE ANGLE X-RAY SCATTERING

摘要

angle scattering with pair distribution function (PDF) analysis was used to follow changes in coals on exposure to reactive gases at high pressures. For example, this approach is being used to better understand the fundamental changes in coal structure when pressurized with CO2, to model carbon sequestration SAXS provides pore size, size distribution, shape and surface morphology over broad length scales. PDF provides atom-atom correlations out to at least 2 nm. SAXS has been used to study coal porosity. A combined SAXS and SANS study confirmed that coals have a very broad distribution in porosity from a few angstroms to microns Upon thermal treatment of bituminous coals at 340 °C, it was observed with SAXS that the mesopore structure had to some extent collapsed.