The pore structure of the Argonne coals as interpreted from contrast matching small angle neutron scattering

Contrast matching small angle neutron scattering has been performed on a series of Argonne coals using H2O/D2O mixtures using short contact times between the coal and liquid. Calculations of the neutron scattering densities of the coals based on their “formulae” and helium densities are discussed. The results of the CM-SANS are given and it is shown that the scattering from the scattering from the non-contrast-matched samples is unreliable. It is shown that porosity in coals is effectively determined by the presence of water and that porosity levels decrease with increasing rank.