Median pore sizes

Grades Color Fibra-Cel/ diatomite blend equiv- alent Median pore size in microns Approx. AP 1 gal/ fC/min with 0.15 lb/ fC precoat Estimated gahfC/hr water 6 in. precoat 24 in. Hg AP Perme- ability Darcies Denisty Ib/fC Dry Wet 150 Mesh % retained % Moisture as shipped pH % Solubles... 

For example, an alumina coating with a median pore size of typically 100 nm can be prepared from a suspension (in water) of commercially available submicron alumina powder with a mass based median diameter of 500 nm. In such a suspension colloidal interactions determine to a large extent the properties of the suspension. The particle packing properties are disturbed by the presence of a fraction of aggregates which always exist in such commercial powders. This fraction can be removed from a colloidally stable suspension by means of sedimentation fractionation (see Ref. [5] for an example). 

Porosity and pore size distribution for catalyst coating application (30-35% open porosity and 4-15 micron median pore size). 

A typical curve relating inaccessible water to solute diameter is shown in Figure 3. The fiber saturation point corresponds to the plateau formed with very large diameter solute molecules while the median pore size is that value above and below which one-half the total volume of... 

We now come to the question of cell wall porosity. Using the solute exclusion technique described in the experimental section, a complete pore size distribution curve was obtained for the wood and for all the pulps of different yield. These curves have been reported elsewhere (14) so will not be repeated here, but the median pore size—i.e.f the size of pore above and below which lies half the total pore volume, is plotted against pulp yield in Figure 8. Qualitatively at least, there is now seen... 

Figure 9. Wood pulps of various yields. Relationship between median pore size and the amount of cellulose dissolved in 24 hours by a rumen inoculum...

Cellulose-Cellulase System. In Figure 10 are shown the accessibility curves of the cotton which had been swollen to different extents by phosphoric acid. The fiber saturation point, given by the amount of water inaccessible to a very large molecule, is seen to increase from 0.48 ml./ gram for cotton treated with water alone to 1.40 ml./gram for cotton swollen in 78.8% acid. The median pore size increased from 23 A. to 52 A. 

Sample Porosity (vol%) Volume Median Pore Size (pm)... 

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