Practical Aspects of Dispersion Formation

Placing a turbine (RDT) in the aqueous or lower phase, close to the interface, can make o/w dispersions. A central interfacial vortex forms with the commencement of impeller motion. This directs a stream of the lighter oil phase to the impeller, where it disperses. The volume of oil layer decreases with continued dispersion until it is exhausted. Placing the turbine in the oil, or upper phase, close to the interface can make w/o dispersions. A water-containing vortex forms, allowing water to be dispersed into the lighter oil phase. 

Dispersions may also be formed by the continuous addition of one phase into another under agitation conditions. This method offers a safe procedure for handling exothermic reactions such as nitration and emulsion polymerization. The amount of phase addition will determine if phase inversion occurs as discussed in Section 12-5.4. 

Listed below are some general recommendations for o/w and w/o systems  

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