What is ISO 15901-1- Mercury porosimetry and gas adsorption studies of solid materials' porosity about?
ISO 15901-1 is a safety standard on mercury porosimetry.
ISO 15901-1 describes a method for the evaluation of the pore size distribution and
the specific surface area of pores in solids by mercury porosimetry according to the method of Ritter and Drake. ISO 15901-1 is a comparative test, usually destructive due to mercury contamination, in which the volume of mercury penetrating a pore or void is determined as a function of applied hydrostatic pressure, which can be related to a pore diameter.
Note: The most used methods in ISO 15901-1 are as follows:
- Mercury porosimetry, where the pores are filled with mercury under pressure. This method is suitable for many materials with pores in the approximate diameter range of 0,004 μm to 400 μm
- Meso- and macropore analysis by gas adsorption, where the pores are characterized by adsorbing a gas, such as nitrogen at liquid nitrogen temperature. The method is used for pores in the approximate diameter range of 0,002 μm to 0,1 μm (2 nm to 100 nm)
- Micropore analysis by gas adsorption, where the pores are characterized by adsorbing a gas, such as nitrogen at liquid nitrogen temperature. The method is used for pores in the approximate diameter range of 0,4 nm to 2 nm
Who is ISO 15901-1- Mercury porosimetry and gas adsorption studies of solid materials' porosity for?
ISO 15901-1 on mercury porosimetry is relevant to:
- Manufacturers of mercury intrusion porosimeters
- Operators
- Testing authorities of porosimetry testing
- Particle technology labs
- Manufacturers of 3P instruments
Why should you use ISO 15901-1 - Mercury porosimetry and gas adsorption studies of solid materials' porosity?
Porosity is a term that is often used to indicate the porous nature of solid material and ISO 15901-1 is more precisely defined as the ratio of the total pore volume of the accessible pores and voids to the volume of the particulate agglomerate.
Mercury porosimetry is a widely accepted method for pore size analysis of various materials such as pharmaceutical tablets, building materials, catalysts, and their supports, mainly because it allows pore size/porosity analysis to be undertaken over a wide range of pore sizes from meso- to macropores with pore widths about 0,004 μm to about 400 μm. In addition to the accessible pores, a solid may contain closed pores which are isolated from the external surface and into which fluids are not able to penetrate. Porous materials may take the form of fine or coarse powders, compacts, extrudates, sheets, or monoliths. Their characterization usually involves the determination of the pore size distribution as well as the total accessible pore volume or porosity. For some purposes, it is also necessary to study the pore shape and interconnectivity and to determine the internal and external specific surface area. The method in ISO 15901-1 is suitable for the study of most porous materials non-wettable by mercury. Samples that amalgamate with mercury, such as certain metals, e.g., gold, aluminium, copper, nickel, and silver, can be unsuitable with this technique or can require preliminary passivation. Under the applied pressure some materials are deformed, compacted, or destroyed, whereby open pores may be collapsed, and closed pores opened. In some cases, it may be possible to apply sample compressibility corrections and useful comparative data may still be obtainable. For these reasons, the mercury porosimetry technique is comparative.
Overall, ISO 15901-1 is useful as it helps with the methods for the estimation of pore volume, pore size distribution, and porosity.
What’s changed since the last update?
BS ISO 15901-1:2016 supersedes BS ISO 15901-1:2005 which is withdrawn.
BS ISO 15901-1:2016 replaces the first edition (BS ISO 15901-1:2005), which has been technically revised. BS ISO 15901-1:2016 also incorporates the corrigendum BS ISO 15901-1:2005/ Cor 1:2007.
