The emulsification of water and crude oil is typically examined and optimized in test tubes by
optical means, i.e., rated outside the porous medium. We examine the rather complex case of crude oil emulsification by alkaline solutions, and follow the question, whether or not those phase behavior experiments are representative for emulsification under the typically laminar flow conditions in porous media. Instead of a qualitative optical evaluation, we use X-ray attenuation coefficients in µCT to establish the material balance during emulsification in the test tubes. We show that in such cases the optical inspection can lead to a considerable misinterpretation of the phase behavior. Using X-ray attenuation makes those experiments
quantitative and comparable to µCT-based core flood experiments, where phase mixing occurs in porous media flow. Using X-ray attenuation, we conclusively show that even in the complex case of in-situ saponification by alkaline flooding, (a) emulsification in test tubes and in porous media flow is comparable, and (b) that a minimum emulsion volume with balanced compositions leads to optimal oil recovery in micro CT-based and conventional core flooding.