Page 7 - Adsorptionbypowders & poroussolids muyace

CONTENTS

5.3.4. Applications of adsorptionfrom solution 157
Assessment of surface area and pore size 157
Adsorption (and displacement) mechanisms 157
References 160
Chapter 6. Assessment of Surface Area 165
6.1. Introduction 165
6.2. The BET method 166
6.2.1. Introducrion 166
6.2.2. The BETplot 166
The single point method 169
6.2.3. Validity of the BET monolayer capacity 169
6.2.4. The BET area 170
6.3. Empirical methods of isotherm analysis 174
6.3.1. Standard adsorption isotherms 174
6.3.2. The t-method 176
6.3.3. The as-method 176
6.4. Adsorption from solution 179
6.5. Immersion microcalorimetry 180
6.5.1. The modified Harkins and Jura 'absolure method' 18
6.5.2. The surface area of microporous carbons 182
6.6. The fractal approach 183
References 187
Chapter 7. Assessment of Mesoporosity 191
7.1. Introduction 19 1
7.2. Capillary condensation and the Kelvin equation 192
7.2.1. Derivation of the Kelvin equation 192
7.2.2. Application of the Kelvin equation 193
7.3. Mesopore volume, porosity and mean pore size 197
7.3.1. Mesopore volume 197
7.3.2. Porosity 198
7.3.3. Hydraulic radius and mean pore size 199
7.4. Computation of the mesopore size distribution 199
7.4.1. General principles 199
7.4.2. Computationprocedure 201
7.4.3. The multilayer thickness 202
7.4.4. Validity of the Kelvin equation 203
7.5. Hysteresis loops 204
7.6. Density functional formulation 213
References 2 15
Chapter 8. Assessment of Microporosity 219
8.1. 1:ltroduction 2 19
8.2. Isotherm analysis 222
8.2.1. Empirical methods 222