MERCURY POROSIMETRY HYSTERESIS AND ENTRAPMENT PREDICTIONS BASED ON A CORRUGATED RANDOM PORE MODEL

This paper advances the concept of mercury porosimetry hysteresis and entrapment, through the development of a probabilistic model simulating the mercury penetration–retraction operations, applied to a one-dimensional model of non-intersecting corrugated pores. The fundamental aspect on which the development of the model is based, is the experimentally observed phenomenon of mercury column breaking, occurring during its capillary flow along a corrugated pore. A mercury column is assumed to break and remain trapped within wide pore sections. Criterion for the entrapment to occur is the condition that the “pore constriction ratio ̻” defined as the ratio of a pore segment size and that of the next in the direction of mercury flow segment, to be lower than some critical value ̻c (0<̻cC<1). Theoretical predictions of the statistical model using a Normal, a Beta and a Bimodal probability density function as the intrinsic pore size distribution have shown that realistic hysteresis loops can be obtained and widely varied amounts (0-85%) of mercury entrapment can be predicted. The potential of the model has been also tested through the curve fitting of MP experimental data obtained on samples of three commercial HDS catalysts. © 1991, Taylor & Francis Group, LLC. All rights reserved.