Liquid Bridging

Pendular Funic alar Capillary Particles dispersed in bridging liquid ... 

Using sands of narrow and wide size distributions suspended in various organic liquids, Capes and Sutherland (C7) have shown that large, compact agglomerates are formed if the amount of the bridging liquid is sufficient to occupy about 44-88% of the pore space in a densely compacted bed of sand particles. The final size distribution attained represents a balance between... 

Fig. 2.3. Liquid junction with free diffusion (a) the test solution is drawn (in the direction of the arrow) into the stopcock (h) the saturated KCl solution from the liquid bridge is drawn into the stopcock (c) by turning the stopcock the test solution/liquid-bridge liquid junction is formed. (After Mattock and Band.)...

Fig. 2.11. Salt distributions in sand agglomerates [26] (31—44/im sand saturated aqueous solution of NaCl as bridging liquid dried at 110° C. (a) agglomerates contained no gelling agent (b) bridging liquid contained 10% w/v corn starch).

Crushing strength of graphite agglomerates [26] (minus 300 mesh graphite, balled with organic bridging liquid and dried at 75° C). 

Bridging liquid Dissolved binder Gelling agent Correlating equation... 

As seen in Fig. 3.6 and consistent with the discussion in the previous section, the theoretical bridging liquid requirements to saturate the powder in a close-packed state lies at intermediate rates of growth. In view of the extreme sensitivity of the growth to liquid content, however, and the previously-indicated inability to predict accurately optimum liquid levels for agglomeration, the constants a and b in eqn. (7) for a particular powder-liquid system and specific agitation conditions must be determined by experiment. 

In applications such as the preparation of tableting feeds and the manufacture of detergent powders, the aim is to produce small agglomerates (usually 2 mm diameter and less) with improved flow, wetting, dispersing or dissolution properties. This is accomplished by superficially wetting the feed powder, often with less than 5% of bridging liquid in the form of a... 

Beyond this region the agglomerates exist as pasty lumps the solids are then essentially dispersed in the bridging liquid. 

The pH scale has been defined operationally, and standard reference solutions based on a conventional scale of hydrogen ion activity have been selected (i, 2). Measurements of the pH of seawater made with different electrodes and instruments are satisfactorily reproducible when standardized in the same way (3). The results obtained, however, do not always have a clear interpretation. Formally, this diflSculty can be attributed to the residual liquid junction potential involved in the measurement. The primary standards are necessarily dilute buffer solutions (ionic strength, I 0.1) whereas seawater normally has an ionic strength exceeding 0.6. This difference in the concentrations and mobilities of the ions coming in contact with the concentrated solution of potassium chloride of which the salt bridge-liquid junction is composed gives rise to a potential difference that is indeterminate. Consequently, the meas-m ed pH is in error by an unknown amount and does not fall exactly on the scale fixed by the primary standards. 

Fig. 6.2-95 Size distribution of SA crystals produced in a three-solvent system [6.2.3.3]. Ethanol 5 ml, bridging liquid (water) O)...

Random coalescence Funicular - Capillary Compaction and spheronization Liberated bridging liquid... 

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