Emulsification Emulsifying Emulsion

If you pour a small amount of oil into a glass of water, the two liquids do not mix. Oil is lighter than water and, after shaking briefly, forms small bubbles that rise and settle as a layer of oil on the surface of the water.

Emulsification means converting such immiscible liquids into a stable mixture. This is done by breaking the oil down into very small droplets. The size of the droplets can be in the micrometer or even nanometer range. Such fine droplets are formed when oil and water are mixed with very high shear energy. The smaller the oil droplets, the more transparent the emulsion appears.

When fine oil droplets are present in water, this is referred to as an oil-in-water emulsion. Conversely, when water droplets are present in oil, this is referred to as a water-in-oil emulsion.

The addition of an emulsifier can accelerate the emulsification process and increase the stability of the emulsion. Lecithin, for example, acts as an emulsifier because it has both fat-soluble and water-soluble components. Surfactants can also be used as emulsifiers. Emulsions can be stable or separate over time. Stabilisers such as cellulose ether or pectin are often added to prevent separation. Typical examples of emulsions are body lotions, sun creams, milk, mayonnaise and lubricants. Emulsions are usually produced with fast-rotating rotor-stator systems or colloid mills.

Special application

in powder mixing technology: In powder mixing technology, it can be difficult to evenly wet hydrophobic powders with aqueous liquids. This process is made easier if the wetting liquid is present as an emulsion. amixon^® mixers are suitable for both dry and moist powders. They are capable of distributing even the smallest quantities of liquid homogeneously in the powder – either with the formation of agglomerates or without lumps.