Single-walled carbon nanotubes (SWNTs) have excited researchers for several years because of their physical and chemical properties. However, most SWNT synthesis techniques result in polydisperse length. Chromatographic or electrophoretic separations have been successful but are typically limited to anylitical scale separations. Recently, a bulk-scale liquid-liquid extraction process was developed for the separation of SWNTs by length. The separation was attributed to the length-dependent van der Waals attractions of SWNTs. These separations, however, often had difficulties with the formation of stabilized emulsions. To further understand the stabilization of emulsions with nanotubes, we have studied the interfacial interactions of a simple system - surfactant suspended SWNT solutions. A simple model has been developed to characterize the free energy changes upon movement of nanotubes from the aqueous phase to the interface. This model predicts that longer nanotubes preferentially adsorb to the interface and that oil-in-water emulsion systems are stabilized by hydrophilic particles.