USE OF ORGANIC ACIDS OR SALT THEREOF IN SURFACTANT-BASED COMPOSITIONS AND TECHNIQUES FOR ENHANCING OIL RECOVERY Russian patent published in 2018 - IPC C09K8/584 C09K8/68 E21B43/22 

FIELD: chemistry.

SUBSTANCE: invention relates to surfactant compositions for use in the treatment and recovery of fossil fluids from a subterranean formation, their production and use. Surfactant composition for treating a fossil fluid-containing subterranean formation comprises a non-ionic surfactant, an organic acid selected from citric acid, diglycolic acid, glycolic acid or a salt thereof and injection water, wherein the non-ionic surfactant is an alkoxylated alkylphenol containing one or more propoxylate groups and one or more ethoxylate groups, wherein the alkyl phenol is a phenol containing one or more attached linear or branched C₁-C₂₅ alkyl groups, and the ratio between the content of the organic acid or salt thereof and the non-ionic surfactant ranges from 0.05:15 to 2:10 parts by weight, respectively. Method for preparing a surfactant composition for treating a fossil fluid-containing subterranean formation includes mixing said non-ionic surfactant with said organic acid or salt thereof and injected water. Method for extracting fossil fluids from a fossil fluid-containing subterranean formation includes injecting said composition into one or more injection wells so as to subsequently extract oil from one or more production wells. Packaging of the surfactant for treating a fossil fluid-containing subterranean formation comprises said non-ionic surfactant and organic acid or salt thereof. Invention is developed in dependent items of the formula.

EFFECT: technical result is an increase in the efficiency of oil recovery, especially at high salinity and temperature.

8 cl