Regarding the effect that different twin-tailed surfactant have on a solid stabilized petroleum emulsion

Abstract

An industrial petroleum emulsion stabilized by colloidal silica particles was treated with four different twin-tailed surfactants: sodium bis-2-(ethylhexyl) sulfosuccinate (AOT), didodecylammonium bromide (DDAB), calcium oleate (Ca(OL)2), and dioctadecyldimethylammonium bromide (DODAB). Fourier transform infrared (FT-IR) spectroscopy, optical microscopy, centrifuge test, and conductivity measurement were employed to determine the effect of the amphiphile molecules on the crude oil emulsion. AOT and DDAB produce emulsion breakdown, while Ca(OL)2 does not alter the emulsion stability and DODAB produces an extra stabilization of it. The AOT adsorption at the oil–water droplet interface is a spontaneous process, which promoted the emulsion breakdown through an interdroplet interaction mechanism. DDAB needs extra energy (via centrifugation) to destabilize the emulsion. Ca(OL)2 dissolves in oil phase and remains there without altering the emulsion strength, while DODAB increases the emulsion stability.