Mixed soap grease

Static mixers are used ia the chemical iadustries for plastics and synthetic fibers, eg, continuous polymeri2ation, homogeni2ation of melts, and blending of additives ia extmders food manufacture, eg, oils, juices, beverages, milk, sauces, emulsifications, and heat transfer cosmetics, eg, shampoos, hquid soaps, cleaning Hquids, and creams petrochemicals, eg, fuels and greases environmental control, eg, effluent aeration, flue gas/air mixing, and pH control and paints, etc. 

The basic common denominator for all these applications is qualitatively well understood surfactants and their aggregates permit mixing, or at least close interaction, between phases or substances that are per se immiscible with each other -mostly oil and water. This is how grease is washed off from our hands when we use soap, the removal being mediated by micelles. In turn, micelles and vesicles permit the formation of an extraordinarily efficient interfacial system. Figure 9.3 gives a dramatic demonstration of this, showing that the total surface of a concentrated soap solution in your sink may well correspond to the surface of a stadium ... 

By associating these oils with proportionate quantities of suet Or tallow, mixtures will be formed, of which soaps of proper quality and consistence can be made. The soaps made from poppy ail are of a dirty grey, without any disagreeable smell are clammy, and of medium consistence. They become yellow in the air, and, when exposed to cold, become soft at the surface. This oil, when mixed with the greases, yields a soap much resembling in appearance that of olive oil. 

Soap molecules contain a long nonpolar end and a small polar end. The polar end contains a negative charge. The nonpolar end of soap mixes with oil, fat, and grease because they are nonpolar. The polar end of soap mixes with water since water is polar. 

Such a molecule can cause particles of grease or oil to mix somewhat with water and to be washed from a dirty article. Calcium and magnesium ions in hard water react with stearate ions to form a solid, yielding soap scum. To avoid this problem, chemists developed synthetic detergents that do not form insoluble salts with calcium and magnesium ions. Synthetic detergents are similar to soaps in that they have an ionic end and a large hydrocarbon-like end. 

How does soap dissolve grease and oil Water alone cannot dissolve dirt, which is composed largely of nonpolar hydrocarbons. When soap is mixed with water, however, the nonpolar hydrocarbon tails dissolve the dirt in the interior of the micelle. The polar head of the soap remains on the surface of the micelle to interact with water. The nonpolar tails of the soap molecules are so well sealed off from the water by the polar head groups that the micelles are water soluble. 

Traditionally metal soaps have been manufactured by reactiOTi of alkali- or alkaline earth oxides or carbonates with natural fats or oils. Both compraients are mixed and at higher temperatures the triglyceride is decomposed yielding metal soap and glycerol. Under such conditions the soap is dispersed in an excess of oil or molten fat, and lubricating greases are yielded that way. 

The availability of a range of soaps, based on different metals, encouraged grease formulators to investigate the effect of mixtures in the final grease. Little benefit was found from this mixed-based approach, although compromise mixtures such as lithium-calcium have found some special applications. 

When soap and grease are mixed, the hydrophobic hydrocarbon tails of the soap insert (or dissolve) into the oil droplet. The oil droplet becomes coated with soap molecules. The hydrophilic portion of the soap molecules allows the soap-oil complex to be dispersed in water. 

Prodncts and Uses The substance used in soap stock, leather dressing, candles, greases, and in animal feeds. It is useful as a coating agent, emulsifying (stabilizes and maintains mixes) agent, formulation aid, and as a texturizer. Derived from animal (cattle) fat. 

The soap was afterwards boiled over a strong salted ley, and the resulting paste mixed, in varying proportions, with other soaps but although the chloride of soda had diminished the peculiar odour of the grease to some extent, it was found that only a small percentage of the fatty acid soap could be worked up with soaps of better quality, and even then a keen nose would recognise its presence. T en... 

For household or laundry purposes he uses by pre-Terence a soap made of oleic acid mixed, with common tallow or animal grease and resin if necessary, he adds a certain proportion of French chalk to give fiimness to the soap. The solution of silicate of soda should have a specific gravity of about 170 by Twaddeil s hydrometer. 

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