The optimal mixture design of experiments: Alternative method in optimizing the aqueous phase composition of a microemulsion

In this paper, an optimum mixture Design of Experiment (DOE) method was used to determine the optimum aqueous phase formulation of a microemulsion. Based on the Design Expert software, a quadratic model was established as a function of the microemulsion component fractions. The model was validated experimentally using an ANOVA table. The diagnostics of the model were also investigated by using Normal Plot of Residuals and Box-Cox Plot. In addition, the effects of the microemulsion component fractions on IFT variation were also studied. Finally, the model was optimized to predict the optimum conditions that would yield minimum IFT. It was observed that the predicted and experimental IFT values at the optimum condition are in good agreement with an error of about 1.5%. The authors concluded that the optimum mixture DOE is reliable and could be used to optimize the composition of a microemulsion system such as enhanced oil recovery (EOR) process. (c) 2011 Elsevier B.V. All rights reserved.