ABSTRACT

Mercury intrusion porosimetry has proven over several decades to be a useful technique in characterizing many porous materials, whose pore sizes range over several orders of magnitude. In 1921, E. Washburn set the theoretical foundations for the technique, and proposed an equation (mentioned in Section 3.1.3) that holds true for any non-wetting liquid in contact with a porous material [3.1]. In 1945, H. Ritter and L. Drake built a mercury intrusion porosimeter and tested a variety of porous materials by penetration of mercury into pores as small as 10nm in radius initially, and 2nm few years later [3.2,3.3]. L. Joyner et al., 1951, calculated surface areas of assumed cylindrical pores from mercury intrusion porosimetry data [3.4]. At around 1960, hydraulic pressurized instruments became commercially available, and since then the technique has been developed and improved to the extent that it is now possible to determine a wide variety of pore structure parameters in porous materials. Such parameters include total pore volume, pore size distribution, density of solids and powders, and specific surface area of pores. In this way, mercury intrusion porosimetry has become a convenient and fast technique for pore structure characterization. The rise in popularity of mercury intrusion porosimetry for pore structure analysis has been due to the fact that the technique is applicable to a broad range of pore sizes more than any other method, since it is comparatively easy to apply a broad range of pressures. Practical advantages of mercury as an intrusion liquid include low vapor pressure, relative inertness in terms of chemical reactivity with many materials, and normally non-wetting properties for most surfaces.