Abstract
The relation between viscosity and stability has been hics. found by investigating the effect of surfactant concentration on emulsion stability. Based on the Bingham plastic model for viscosity as a function of shear rate, two parameters were found to relate the relative stability to the surfactant concentration. The parameters are yield stress (10) and high shear limit viscosity (n.). Based on the Pal and Rhode viscosity equation derived for both Newtonian and non-Newtonian emulsions, the parameter N which represents the emulsion droplet surface area occupied by one surfactant molecule head was calculated. This parameter provides information about the packing structure of the surfactant on droplets and is closely related to the stability. It can therefore be used as an index for predicting the relative stability of emulsions with different surfactant concentrations. The relation found between viscosity and stability in this work allows estimation of the optimal surfactant concentration for the most stable emulsion, without performing the traditional real-time required sedimentation test.
Ye, Sherry Qianwen (1998). Relation between viscosity and stability for heavy oil emulsions. Master's thesis, Texas A&M University. Available electronically from
https : / /hdl .handle .net /1969 .1 /ETD -TAMU -1998 -THESIS -Y35.