The Effect of Pressure on Pore Structure in Mercury Porosimetry

• Main Authors: A.M.L. Hustings, J.J.F. Scholten
• Format: Article
• Language: English
• Published: Hindawi - SAGE Publishing 1987-12-01
• Series: Adsorption Science & Technology
• Online Access: https://doi.org/10.1177/026361748700400404

The pore volume distributions of chrysotile, Mg 3 (OH) 4 . Si 2 O 5 , ZrO 2 and of four samples of silica with pore volumes from 1.45 to 2.70 cm 3 /g have been measured by means of nitrogen capillary condensation and mercury penetration. It is shown that compaction of the porous structures can occur under the influence of the high mercury pressures applied. The degree of compaction depends on the mechanical strength of the sample, its initial porosity and the magnitude of the mercury pressure. The extremely strong ZrO 2 sample, with its low pore volume of 0.18 cm 3 /g does not show any sign of cracking up to pressures as high as 190 MPa. Hollow chrysotile needles compact in the pressure range from 100 to 400 MPa. Highly porous silicas all show severe compaction. In accordance with Brown & Lard (Brown & Lard, 1974) it is concluded that silicas with pore volumes larger than 1.2 cm 3 /g are not suitable for study by mercury porosimetry.