| CPC C09K 8/584 (2013.01) [C09K 8/588 (2013.01); E21B 43/16 (2013.01)] | 16 Claims |

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1. A pressure injection method of enhanced oil recovery, comprising:
injecting a mixture into a carbonate rock formation comprising an oil composition at an injection pressure of 100-5,000 psi; and
extracting the oil composition from the carbonate rock formation,
wherein the mixture comprises 89-98.9 vol % of an aqueous solution, 0.01-1 vol % of a gemini cationic surfactant, and 0.1-10 vol % of formic acid based on a total volume of the mixture, and
wherein during the injecting at least a portion of the gemini cationic surfactant is adsorbed onto the carbonate rock formation, and wherein at least 90% less by volume of the gemini cationic surfactant adsorbs onto the carbonate rock formation compared to a method under the same conditions but without the formic acid.
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