Influence of Semibatch Emulsification Process Conditions on The Physical Characteristics of Highly Concentrated Water-in-Oil Emulsions

We studied the energy consumption per unit volume during preparation of highly concentrated water-in-oil emulsions in a two-step semibatch process. In particular, we studied the effect of two process variables, the water addition flow rate (Q(w)) and the agitation speed (N). The oil used for emulsion preparation was n-dodecane, the surfactant was sorbitan monooleate (Span 80) and deionized water was used for the dispersed phase. The results obtained showed that two steps were required to get complete incorporation of the dispersed phase and a homogeneous and stable gel-emulsion. With the help of independent physical characteristics measurement performed at the end of the preparation process, we established two functional relationships, relating storage modulus (G') with energy consumption (E-v), (G' proportional to E-v(0.6)), and average liquid cell size (R-m) of the dispersed phase with energy consumption (E-v), (R-m proportional to E-v(-0.3)). A structural scaling law can be deduced that relates the elastic modulus to the reciprocal of the square of the average liquid's cell size of the gel-emulsion, corroborated by independent measurements and predicted by recent published models.