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Wetting by Organic Liquids

Comparative Immersional Heat Values for Hydrophobic and Hydrophilic Solids [Pg.280]

Heats of immersion of two solids with widely different surface characteristics 39) are given in Table IV. Rutile (TiOz) is a heteropolar hydrophilic solid, and Graphon is homopolar and hydrophobic. A homologous series of alcohols and hydrocarbons and several n-butyl derivatives are the wetting liquids. Water is included for comparison. [Pg.280]

The heat values are markedly higher for the polar solid immersed in polar liquids they also vary considerably with the functional group of the liquid. For Graphon, however, the heats are almost unaffected by the structural features of the wetting liquid. This nonpolar solid, despite the presence of a small amount of hydrophilic sites on its surface 0), interacts with the liquids primarily through London dispersion forces. Because of the additive nature of these forces, each adsorbed molecule tends to lie flat on such a surface 40). In the case of a polar molecule the functional group is oriented somewhat away from the nonpolar surface toward the liquid. [Pg.280]

The Interaction of Polar Solids with Organic Liquids [Pg.280]

The electrostatic force field emanating from the surface of a polar solid exerts a strong orienting influence on molecules possessing peripheral [Pg.280]


An alternative method of improving wettability was first described by Groszek , and has been described in Section 7.6. This is the production of oleophilic molybdenum disulphide by ball milling in oil. The product is readily wetted by organic liquids, and can in fact be used as a grease thickener. Groszek described dispersions in several different organic liquids and it is clear that the improved wettability leads to the formation of much more stable dispersions. [Pg.134]

The real atmosphere is more than a dry mixture of permanent gases. It has other constituents—vapor of both water and organic liquids, and particulate matter held in suspension. Above their temperature of condensation, vapor molecules act just like permanent gas molecules in the air. The predominant vapor in the air is water vapor. Below its condensation temperature, if the air is saturated, water changes from vapor to liquid. We are all familiar with this phenomenon because it appears as fog or mist in the air and as condensed liquid water on windows and other cold surfaces exposed to air. The quantity of water vapor in the air varies greatly from almost complete dryness to supersaturation, i.e., between 0% and 4% by weight. If Table 2-1 is compiled on a wet air basis at a time when the water vapor concentration is 31,200 parts by volume per million parts by volume of wet air (Table 2-2), the concentration of condensable organic vapors is seen to be so low compared to that of water vapor that for all practical purposes the difference between wet air and dry air is its water vapor content. [Pg.21]

Comparing equations 13.8 and 13.9, it is seen that the adiabatic saturation temperature i > equal to the wet-bulb temperature when s = h/hDpA. This is the case for most water vapour systems and accurately so when Jf = 0.047. The ratio (h/hopAs) = b is sometimes known as the psychrometric ratio and, as indicated, b is approximately unity for the air-water system. For most systems involving air and an organic liquid, b = 1.3 - 2.5 and the wet-bulb temperature is higher than the adiabatic saturation temperature. This was confirmed in 1932 by SHERWOOD and COMINGS 2 who worked with water, ethanol, n-propanol, n-butanol, benzene, toluene, carbon tetrachloride, and n-propyl acetate, and found that the wet-bulb temperature was always higher than the adiabatic saturation temperature except in the case of water. [Pg.745]

It is clear from a consideration of equation (i) that liquids of low surface tension, i.e. small values of aig are more likely to wet solids than liquids of high surface tension. Thus the organic hydrocarbons of low surface tension readily wet most solid surfaces water will wet but a limited variety of surfaces whilst the displacement of the adsorbed air film from solids by mercury is a comparatively rare occurrence. We find also (equation (ii)) that oil will displace... [Pg.169]

The process is characterised by the electrofluorination of volatile organic substrates within the matrix of pores of a carbon anode immersed in molten KF 2HF as electrolyte (as in a mid-temperature fluorine generator cell), and depends on the phenomenon that the anodically charged porous carbon is not wetted by the electrolyte. The fluorination probably takes place at the three phase interface of organic vapour, solid carbon, and liquid electrolyte in close proximity to, or at the sites where fluorine is being evolved. [Pg.210]


See other pages where Wetting by Organic Liquids is mentioned: [Pg.263]    [Pg.280]    [Pg.44]    [Pg.91]    [Pg.250]    [Pg.97]    [Pg.263]    [Pg.280]    [Pg.44]    [Pg.91]    [Pg.250]    [Pg.97]    [Pg.450]    [Pg.191]    [Pg.334]    [Pg.234]    [Pg.729]    [Pg.257]    [Pg.227]    [Pg.537]    [Pg.105]    [Pg.543]    [Pg.150]    [Pg.80]    [Pg.521]    [Pg.364]    [Pg.2317]    [Pg.21]    [Pg.142]    [Pg.227]    [Pg.648]    [Pg.649]    [Pg.102]    [Pg.69]    [Pg.95]    [Pg.33]    [Pg.8]    [Pg.139]    [Pg.270]    [Pg.288]    [Pg.705]    [Pg.2]    [Pg.265]    [Pg.579]    [Pg.245]    [Pg.161]    [Pg.26]    [Pg.229]    [Pg.181]    [Pg.387]   


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Organic liquids

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