Dispersion Hydrogenation, fatty acids

The Hildebrandt parameter St can be calculated with the three Hansen solubility parameters in consideration of the dispersive Sj, polar 5p, and hydrogen S bonding components. Thus, the interaction between the fatty acids (FA) used as pure substances and bonded onto the magnetite surface (FA Fe304) could be characterized [15, 22]. The calculated values are presented in Table 1 and the following correlation applies The smaller the value, the more soluble is the surfactant in the solvent. 

Tlie carboxylate salts of fatty acids have long, nonpolar, hydrocarbon chains. Therefore, they do not form solutions of individual ions, but are dispersed as weakly associated structures called micelles, which are spherical aggregations of molecules or ions. In a micelle of carboxylate salts, the nonpolar hydrocarbon chains occupy the interior of the sphere, and the polar carboxylate heads lie on the surface of the sphere. This spherical arrangement encloses the maximum amount of hydrocarbon material in the smallest surface area. Therefore, a micelle disrupts the hydrogen-bonded structure of water to the smallest extent possible. 

The waste paper is dispersed in water (12-15%), and the pH is adjusted to 10-11 with sodium hydroxide. Hydrogen peroxide is added to prevent yellowing. The suspension is treated by - flotation. - Soaps and - fatty acids (forming Ca-soaps with the hardness of the water or the fillers) are used as dirt collectors and flotation agents. The re-... 

As far as catalytic properties are concerned, nickel and cobalt catalysts rank among those most often described and used in the production of primary amines from higher fatty acids via the hydrogenation of the corresponding nitriles. It was also assumed in previous papers that when nickel is deposited on a support, only the degre of nickel dispersion is affected and there is no substantial modification of the selectivity (5). 

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