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Porosimetry is an analytical technique used to determine various quantifiable aspects of a material's porous structure, such as pore diameter, total pore volume, surface area, and bulk and absolute densities. The technique involves the intrusion of a non-wetting liquid (often mercury) at high pressure into a material through the use of a ...
[10] [11] This is in effect an "ice intrusion" measurement (c.f. Mercury Intrusion Porosimetry), and as such in part may provide information on pore throat properties. The melting event was then previously expected to provide more accurate information on the pore body.
Mercury intrusion porosimetry [13] and gas adsorption [14] are common techniques for determining the pore size distribution of materials and power sources. When studying the pore size distribution using the gas adsorption technique utilizing the nitrogen or argon adsorption isotherm at their boiling temperatures, it is possible to determine the ...
Mercury intrusion porosimetry (several non-mercury intrusion techniques have been developed due to toxicological concerns, and the fact that mercury tends to form amalgams with several metals and alloys). Gas expansion method. [6] A sample of known bulk volume is enclosed in a container of known volume.
In capillary flow porometry, in opposition to mercury intrusion porosimetry, the wetting liquid enters spontaneously the pores of the sample ensuring a total wetting of the material, and therefore the contact angle of the wetting liquid with the sample is 0 and the previous formula can be simplified as: P= 4*γ/D.
In mercury porosimetry, the mercury is forced into the aerogel porous system to determine the pores' size, but this method is highly inefficient since the solid frame of aerogel will collapse from the high compressive force. The scattering method involves the angle-dependent deflection of radiation within the aerogel sample.
Another method of determining the pore size distribution is by using a procedure known as Mercury Injection Porosimetry. This uses the volume of mercury taken up by the solid as the pressure increases to create the same isotherms mentioned above. An application where pore size is beneficial is in regards to oil recovery. [13]
BET model of multilayer adsorption, that is, a random distribution of sites covered by one, two, three, etc., adsorbate molecules. The concept of the theory is an extension of the Langmuir theory, which is a theory for monolayer molecular adsorption, to multilayer adsorption with the following hypotheses: