Sugar-Based Ethoxylated Amine Surfactants as Demulsifiers for Crude Oil Emulsions: 2- Demulsification of Different Types of Crudes

The present work studies demulsification of two types of crude oil emulsions by nine sugar-based ethoxylated amine surfactants. The effect of pH and salinity of aqueous phase of crude oil on emulsion stability was considered, and the correlation between demulsification rate and the type of crude was studied. Nine sugar-based ethoxylated amine surfactants were tested as demulsifiers for light and heavy crudes at different aqueous phase conditions. It was found that the light crude was more easily demulsified than the heavy crude. The experimental data showed that changes in pH or salinity of the aqueous phase of the emulsion enhance its stability and decrease the demulsification efficiency of the applied demulsifiers. Also, it has been shown that surfactants based on glucose octyl amine ethoxylates (GO) are the most effective in demulsifying the investigated emulsions. The data reveal that maximum demulsification efficiency is attained at a neutral pH whereas it decreases in both directions for either of the investigated crude oils. Furthermore, the results indicate that the percentage of water separation decreases as the salinity of the emulsion’s aqueous phase increases. Light crudes showed better demulsification than heavy crudes under any test condition. The demulsification process for selected emulsions was monitored by optical microscopy.