How does one store, pump, and apply wax to surfaces effectively without incurring the heating cost to maintain the wax above its melting point? How does one efficiently and evenly apply oils? How does one pump, transport, store, or apply tarlike heavy bitumen and asphalt? The answer to these and many other application-oriented problems is with emulsions. An emulsion allows one to prepare a low viscosity, pumpable fluid containing a material that would otherwise be unmanageable.
No particular problems are posed in preparing lignosulfonate-stabilized emulsions. Lignosulfonates are completely soluble in water and are insoluble in most organic liquids. It is preferable, though not essential, to add the oil phase as a slow, uniform stream to a solution of lignosulfonate passing through the homogenizer. However, water and oil may be mixed, a lignosulfonate powder added, and the entire mixture emulsified mechanically as the last step; or a solution of lignosulfonate may be added to the oil, mixed mechanically to produce a stable oil-in-water emulsion.
Emulsions may be prepared with lignosulfonate solution ranging from 0.5% to 10.0% lignosulfonate in the water phase and with oil concentrations up to 75% by weight. Different oils may require various amounts of lignosulfonate.
The concentration of oil desired in the final emulsion is an important factor in determining the amount of lignosulfonate to use. If a dilute emulsion is required, it is suggested that a masterbatch emulsion be prepared and this concentrated emulsion then be diluted. With a large amount of oil in the emulsion, more time will be required in homogenizing.
The products will also enhance dispersion of micelles which makes the emulsion itself highly homogeneous. In addition, the emulsions display excellent resistance to changes in pH and temperature.