(144b) Effects of Interfacial Polymer Co-Adsorption on the Spontaneous Emulsification in the Presence of Asphaltenes

Authors: 
Rodriguez-Hakim, M., Stanford University
Bochner de Araujo, S., Stanford University
Fuller, G. G., Stanford University
Yao, Z., Zhejiang University
Asphaltenes are complex, high molecular weight compounds found in crude oils defined by their high solubility in toluene and low solubility in n-heptane. When an asphaltene-toluene solution is brought into contact with water, asphaltenes tend to adsorb onto the oil-water interface and form a viscoelastic layer. Previous work has revealed that the interfacial adsorption of asphaltenes induces a spontaneous emulsification phenomenon, where micron-sized droplets spontaneously appear at the interface (Bochner de Araujo et al, 2017). In this work, we examine the spontaneous emulsification phenomenon occurring when asphaltenes adsorb onto a toluene-water interface. We study the effect of the addition of poly(styrene-alt-octadecyl maleimide) (SNODMI), a co-polymer found to increase crude oil flowability, on the extent and rate of spontaneous emulsification (Cao et al, 2016). We find that the SNODMI molecules competitively adsorb onto the toluene-water interface, lowering the interfacial energy and inhibiting spontaneous emulsification. Finally, we conduct interfacial rheology measurements in an effort to understand whether interfacial rigidity plays a role in the propensity of a system to spontaneously emulsify.