Separation profile of model water-in-oil emulsions followed by nuclear magnetic resonance (NMR) measurements: application range and comparison with a multiple-light scattering based apparatus

Sébastien Simon; Xavier Pierrard; Johan Sjöblom; Geir H Sørland

doi:10.1016/j.jcis.2011.01.012

Separation profile of model water-in-oil emulsions followed by nuclear magnetic resonance (NMR) measurements: application range and comparison with a multiple-light scattering based apparatus

J Colloid Interface Sci. 2011 Apr 1;356(1):352-61. doi: 10.1016/j.jcis.2011.01.012. Epub 2011 Jan 11.

Authors

Sébastien Simon¹, Xavier Pierrard, Johan Sjöblom, Geir H Sørland

Affiliation

¹ Department of Chemical Engineering, The Norwegian University of Science and Technology (NTNU), Trondheim, Norway. sebastien.simon@chemeng.ntnu.no

PMID: 21288535
DOI: 10.1016/j.jcis.2011.01.012

Abstract

The application range and validity of two new NMR sequences (hereafter called sequence 1 and sequence 2) for the study of water-in-oil emulsions (w/o) has been assessed using model emulsions and comparison with results obtained by a commercial apparatus (Turbiscan). These new NMR sequences allow to determine the brine profile i.e. the vertical variations of the dispersed phase content (brine) in the NMR tube. Measuring these parameters as a function of time allows to monitor the separation (sedimentation and coalescence rate) between oil and water. The results obtained on model water-in-oil emulsions with both NMR sequences are consistent and meaningful for both stable and coalescing emulsions and are similar, even if not strictly identical, to the ones obtained with the Turbiscan. It also appears that the second NMR sequence is faster (30s to obtain a profile compared with 3 min for the 1st one in the conditions used in this article) and has a broader application range. Indeed, for these two methods, the oil phase must have a viscosity higher or equal than values which is around 5 mPas for the sequence 2 and 20-25 mPas for the method 1.