From Particle Formation...
... To Particle Characterisation

Pore size distribution by mercury intrusion porosimetry

Mercury porosimetry for the characterisation of porous materials


Mercury intrusion porosimetry is a technique used to measures pore size and pore volume distribution of pores from 0.0036 micron to over 950 micron diameter.

The operation of all mercury porosimeters is based upon the physical principle that a non-reactive, non-wetting liquid will not penetrate fine pores until sufficient pressure is applied to force its entry. The relationship between the applied pressure and the pore diameter into which mercury will intrude is given by the Washburn equation: D = (-4? cos ?)/P where P is the applied pressure, D is the pore diameter, ? is the surface tension of the mercury (480 dyne cm-1) and ? is the contact angle between mercury and the pore wall, usually taken as 140 o.

Monitoring mercury volume intruded as a function of pressure permits the generation of pore size and pore volume distribution isotherms with software adding more characterisation models:

  • Cumulative pore volume versus pressure or pore diameter
  • Cumulative surface area versus pressure or pore diameter
  • Differential pore volume versus pressure or pore diameter
  • Differential pore area versus pressure or pore diameter
  • Pore number fraction versus pressure or pore diameter
  • Particle size distribution
  • Pore tortuosity
  • Permeability
  • Throat to pore ratio
  • Fractal dimensions
  • Statistical mean, mode and median
  • Sample compressibility
  • Bulk density and apparent density
  • Percent of porosity

Control of porosity in terms of pore volume, pore size and their distribution is important for hundreds of industries such as catalysts, ceramics, electrodes, medical devices, pharmaceutical, construction materials and many others.

Read more about pore size distribution and analysis.

For more information contact us.

Pore size distribution by mercury intrusion porosimetry

More information on our range of mercury porosimetry porosimeters (PoreMaster Series)