Measurement of the morphology of high surface area solids: Porosimetry of agglomerated particles

Mercury intrusion porosimetry is a primary method of characterizing the morphology of high surface area solids. Based on a series of pressed microspheres, we have developed a three-dimensional interconnected network model for the void structure. As contrasted to the conventional model involving nonintersecting cylindrical pores (which are neither), a new perspective on porosimetry is discussed. Intrusion is controlled by constrictions, "throats," in the structure and extrusion is controlled by openings, "pores," in the structure. Because porosimetry is sequential, there is statistical deviation between the actual and measured "throats" and "pores." This comparison between scanning porosimetry data and the simulation of porosimetry provides a consistent method for interpreting the morphology of agglomerated particles.