Ultralow interfacial tension in enhanced oil recovery (EOR)

Increasing energy demands require improved methods for enhanced oil recovery (EOR). Chemical EOR methods are most promising for maximum oil recovery, but, so far, limited due to high costs of chemicals and environmental concerns. Therefore, there is a huge interest in optimizing procedures for chemical EOR that minimize the amount of chemicals needed and rely on natural compounds, thus decreasing costs and environmental stress. In this application report we review how spinning drop tensiometry can be used to optimize liquid compositions for improved oil recovery yields. Interfacial tension (IFT) between crude oil and aqueous solution of varying composition down to 5·10 mN/m were reliably measured with a Spinning Drop Tensiometer SITE100. At such low IFT values, microemulsions are formed that dramatically increase residual oil recovery.