Transport properties, such as permeability, are significant in evaluating the production capacity of petroleum reservoir rocks. When a new reservoir is discovered, the most crucial parameter that needs to be determined by reservoir engineers is the rock permeability. Because the permeability of rocks is controlled not only by porosity, but also, and perhaps more importantly, by pore size distribution (PSD) and pore connectivity, a quantitative understanding of the PSD in petroleum reservoir rocks is critical in the evaluation of reservoir capacity. For example, two sandstones having similar porosities can have different permeabilities because of the variance in the PSD, degree of cementation, and tortuosity (PoA) of the porous media, all of which are critical to determining hydrocarbon production of the rocks. Within this context, a new method combining digital image analysis with an empirical equation was used to evaluate the pore geometry in thin sections of ten sandstone samples as a function of pore size distribution in three dimensions (3D) and tortuosity in 2D. Comparing the results of the PSD (3D), tortuosity (PoA), and the degree of cementation for ten samples shows that the extensive calcite cement in sample 1 is the primary control on porosity and permeability of the sample. On the other hand, the dominant pore diameter (R2=0.73), the value of the PSD slope (pore population density/mean length of pore, R2=0.70), and PoA (R2=0.64) are the leading controlling factors in permeability of the remaining nine samples. In this study, the samples having similar porosities (samples 3 and 5, and samples 4 and 6) have different distributions of pore sizes and different pore tortuosity, resulting in significant differences in the dominant pore diameters (149.3 m and 42.6 micrometrem, and 52.9 micrometrem and 138.2 micrometrem, respectively), the values of the PSD slope ( -11 and -44, and -36 and -13, respectively) and PoA (52 mm-1 and 140 mm-1, and 118 mm-1 and 62 mm-1, respectively). These data reveal that permeability increases with increasing dominant pore diameter and the PSD slope, while PoA decreases with increasing permeability. In addition to providing an estimation of permeability for the sandstones with similar porosity, this method can be extended to evaluate pore size distribution as a function of depth in a drill core, percent of pores in each class interval and pore types and pore geometry.

The growth of interest in newly developed porous materials has prompted the writing of this book for those who have the need to make meaningful measurements without the benefit of years of experience. One might consider this new book as the 4th edition of "Powder Surface Area and Porosity" (Lowell & Shields), but for this new edition we set out to incorporate recent developments in the understanding of fluids in many types of porous materials, not just powders. Based on this, we felt that it would be prudent to change the title to "Characterization of Porous Solids and Powders: Surface Area, Porosity and Density". This book gives a unique overview of principles associated with the characterization of solids with regard to their surface area, pore size, pore volume and density. It covers methods based on gas adsorption (both physi and chemisorption), mercury porosimetry and pycnometry. Not only are the theoretical and experimental basics of these techniques presented in detail but also, in light of the tremendous progress made in recent years in materials science and nanotechnology, the most recent developments are described. In particular, the application of classical theories and methods for pore size analysis are contrasted with the most advanced microscopic theories based on statistical mechanics (e.g. Density Functional Theory and Molecular Simulation). The characterization of heterogeneous catalysts is more prominent than in earlier editions; the sections on mercury porosimetry and particularly chemisorption have been updated and greatly expanded.

The importance of porosity has long been recognized by scientists and engineers. Porous solids are widely encountered in industry and everyday life and their behaviour, e.g. chemical reactivity, adsorptive capacity, and catalytic activity is dependent on their pore structure. A considerable amount of work on porous solids has been undertaken both in academic and in industrial laboratories. However, all this activity is in urgent need of a critical appraisal. To undertake this task, a number of leading experts in the field of adsorption, porosimetry, X-ray and neutron scattering, optical and electron microscopy, calorimetry and fluid permeation, were brought together at the 1987 IUPAC (COPS I) Symposium.This proceedings volume provides an up-to-date overall review of the theoretical foundations for modelling and characterizing porous systems. It deals with most of the techniques in current use as applied to both model systems and porous solids of industrial importance. The reader will find the description and discussion of a number of novel techniques as well as a critical appraisal and comparison of the more established methods. All those concerned with the characterization of porous solids in academic and industrial laboratories will find much to interest them in this volume. It should be on the bookshelf of applied research centres involved in adsorption, catalysis, purification of gases and liquids, pigments, fillers, building materials, etc.

The declared objective of this book is to provide an introductory review of the various theoretical and practical aspects of adsorption by powders and porous solids with particular reference to materials of technological importance. The primary aim is to meet the needs of students and non-specialists who are new to surface science or who wish to use the advanced techniques now available for the determination of surface area, pore size and surface characterization. In addition, a critical account is given of recent work on the adsorptive properties of activated carbons, oxides, clays and zeolites. - Provides a comprehensive treatment of adsorption at both the gas/solid interface and the liquid/solid interface - Includes chapters dealing with experimental methodology and the interpretation of adsorption data obtained with porous oxides, carbons and zeolites - Techniques capture the importance of heterogeneous catalysis, chemical engineering and the production of pigments, cements, agrochemicals, and pharmaceuticals

The rapid growth of interest in powders and their surface properties in many diverse industries prompted the writing of this book for those who have the need to make meaningful measurements without the benefit of years of experience. It is intended as an introduction to some of the elementary theory and experimental methods used to study the surface area, porosity and density of powders. It may be found useful by those with little or no training in solid surfaces who have the need to quickly learn the rudiments of surface area, density and pore-size measurements. Syosset, New York S. Lowell May, 1983 J. E. Shields Xl List of symbols Use of symbols for purposes other than those indicated in the following list are so defined in the text. Some symbols not shown in this list are defined in the text. d adsorbate cross-sectional area A area; condensation coefficient; collision frequency C BET constant c concentration D diameter; coefficient of thermal diffusion E adsorption potential f permeability aspect factor F flow rate; force; feed rate 9 gravitational constant G Gibbs free energy GS free surface energy h heat of immersion per unit area; height H enthalpy Hi heat of immersion Hsv heat of adsorption BET intercept; filament current k thermal conductivity; specific reaction rate K Harkins-Jura constant I length L heat of liquefaction M mass M molecular weight n number of moles N number of molecules; number of particles N Avagadro's number .