Simulation of Nonwetting Phase Entrapment within Porous Media Using Magnetic Resonance Imaging

Models representing the pore structures of amorphous, mesoporous SiO2 pellets were constructed using magnetic resonance images of the materials. Using magnetic resonance imaging (MRI), maps of the macroscopic (.apprx.0.01-1 mm) spatial distribution of porosity and pore size were obtained. The nature and key parameters of the phys. mechanism for Hg retraction, during porosimetry expts. on the SiO2 materials, were detd. using integrated gas sorption expts. Subsequent simulations of Hg porosimetry within the structural models derived from MRI were used to successfully predict, a priori, the point of the onset of structural hysteresis and the final levels of Hg entrapment for the silicas. Hence, a firm understanding of the phys. processes of Hg retraction and entrapment in these amorphous SiO2 materials was established. [on SciFinder (R)]