Study On The Effect Of Emulsifier And Heavy Crude Component On Interfacial Properties Of Emulsion

The Gudao and Liaohe heavy crudes were separated into saturate, aromatic, resin and asphaltene by the method of adsorption chromatography. Toluene and n-dodecane mixture were taken as the solvent, Sodium dodecylbenzene sulfonate and OP-10 were selected as emulsifiers. The effect of polar components in oil-in-water emulsion and also the interaction between polar components and emulsifier were investigated by determining the interfacial properties of system added different polar components and different emulsifiers. The effect of component interaction on simulated oil was also studied.The result of the experiment shows that, components of two heavy crudes all contain aromatic ring, also pyrrole ring, carboxyl and other heteroatom polar group ,but have different element constitute, acid number, basic nitrogen content, molecule weight and structure. Their interfacial activity are different. The interaction between polar components and emulsifier exits. The interaction is different according to the interfacial activity of polar components, and the higher interfacial activity, the greater interaction is.The pH value is an important factor for interfacial tension(IFT) and of polar components. The higher interfacial activity of components are, the effect of pH value on interfacial tension and Zeta potential is higher. The interfacial tension could be lower in alkaline condition.The interaction between polar components and two kinds of emulsifiers are different.The interaction between polar components and dodecylbenzene sulfonates is stronger than the interaction between polar components and OP-10, and the synergistic effect is stronger.The saturate of both Gudao and Liaohe heavy crudes have synergic effect with asphaltene to increase the IFT and decrease the absolute value of Zeta potential, thus weakened the emulsion. When the concentration of aromatic and resin are all lower than 8 percent, the synergic effect with asphaltene to decrease the IFT and increase the absolute value of Zeta potential, thus stabilized the emulsion. The synergic effect between Gudao saturate, aromatic, resin and asphaltene is stronger than that of Liaohe. The synergic effect between saturate and resin of both crude oils are not distinct, while the inhibiting effect between aromatic and resin is distinct when the concentration of aromatic are higher than 16 percent, to increase the IFT and decrease the absolute value of Zeta potential, the stability of the emulsion was weakened.The relation of component structure and its performance of decrease interfacial tension show that components can operate with emulsifier to decrease interfacial tension which has high aromatic carbon content, low alkyl carbon content, light degree of branching and high condensation extent of aromatic ring.