In Pore Size Distribution (Porosimetry) measurements, such as Mercury Intrusion Porosimetry (MIP) or Liquid Extrusion Porosimetry (LEP), the pore sizes of a medium are measured by pressing a non-wetting liquid or gas into it and registering the applied pressure and absorbed volume. The pressure applied is related to the radius of the pores accessible to the non-wetting liquid, which gives a size distribution of the pores. Closed pores do not contribute to the pore volume at all, while other pores only contribute to the pore volume fraction if they are connected to the non-wetting phase reservoir (e.g. the mercury reservoir). Find more details about the theory behind the Porosimetry in the Theoretical Basics section.

The parameters of Porosimetry are similar to those of Pore Size Distribution (Granulometry), but fewer large pores are found by Porosimetry than by Granulometry. The reason for this is that a big pore in the interior of the volume must be reached from the intrusion sides, usually through a small diameter pore-throat. The big pore is counted as pore volume of a certain diameter only if a sphere with this diameter can be pushed from the intrusion side through the pore-throat to reach the big pore. In other words, porosimetry provides a measure of the pore-throat size distribution.

The Pore Size Distribution (Porosimetry) dialog opens when clicking the Edit… button.