Porosimeters are instruments that are capable of measuring pore volume and pore volume distribution. These instruments are based on the principle of either liquid intrusion into pores or liquid extrusion from pores.
Mercury cannot flow spontaneously into pores of many porous materials, but application of pressure on mercury can force it into pores. The pressure required to force mercury into pores gives the pore diameter and the volume of intruded liquid gives pore volume and pore volume distribution. Mercury Intrusion Porosimeters are based on this principle and are capable of operating under a wide range of pressures.
Liquids like water, oil, and other chemicals do not wet a number of porous materials. Pressure can be used to force liquids into pores. Nonmercury intrusion porosimeters are based on the intrusion of nonmercury liquids over wide pressure ranges.
For extrusion porosimetry, wetting liquids are used to spontaneously fill pores in the porous materials. Liquid is displaced from pores by applying differential pressure on the sample and volume of extruded liquid is measured. Pressure yields pore diameter, and volume of extruded liquid gives pore volume and pore distribution. Liquid extrusion porosimeters are based on this principle. These instruments have additional capability to measure liquid flow rate.
Compression LEP - New!
Mercury/Non-Mercury Intrusion Porosimeters
Water Intrusion Porisometers