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Flournoy Kenoth H, Cardenas Ricardo L, Haferkamp Gilbert L, Shupe Russell D: Surfactant oil recovery process usable in formations containing water having high concentrations of polyvalent ions such as calcium and magnesium. Texaco, Whaley T H, Reis C G, May 21, 1974: US3811505 (87 worldwide citation)

A dual surfactant system usable in the presence of from about 500 to about 9,000 parts per million polyvalent ions, such as calcium and/or magnesium, and a method of using said surfactant system for recovering petroleum from subterranean formations, said surfactant system comprising a water soluble ...


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Flournoy Kenoth H, Cardenas Ricardo L, Haferkamp Gilbert L, Shupe Russell D: Surfactant oil recovery process usable in formations containing water having high concentrations of polyvalent ions such as calcium and magnesium. Texaco, Whaley T H, Reis C G, May 21, 1974: US3811504 (75 worldwide citation)

A three component surfactant system usable in the presence of from about 1,500 to about 12,000 parts per million polyvalent ions, such as calcium and/or magnesium, and a method of using said surfactant system for recovering petroleum from subterranean formations, said surfactant system comprising a ...