Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Use of highly saline ethoxylated surfactant system for oil recovery

Patent ·
OSTI ID:7301207

An aqueous solution of a sulfated polyoxylated primary alcohol and a soluble inorganic electrolyte was used for enhanced oil recovery. The electrolyte should be present in a concentration exceeding the critical concentration for forming a two-phase coacervate system, by an amount sufficient to convert the two-phase system to a turbid dispersion. The dispersion permits an interfacial tension with petroleum of 10/sup -4/ dynes/cm. A berea core (400 md) was flooded to residual oil saturation before flooding with a 4 M sodium chloride brine which contained Tergitol 15-S4 (4 ethylene oxide units, sodium salt). A 1 PV slug of the surfactant solution left only about 7 percent PV of oil.

Assignee:
Shell Oil Co.
Patent Number(s):
US 3500923
OSTI ID:
7301207
Country of Publication:
United States
Language:
English