Process for producing mineral oil using surfactants based on a mixture of C24 guerbet-, C26 guerbet-, C28-guerbet containing hydrocarbyl alkoxylates

摘要

The present invention relates to a surfactant mixture comprising at least three ionic surfactants which differ in terms of the hydrocarbyl moiety (R1)(R2)—CH—CH2— and are of the general formula (I);
where R1, R2, A0, k, X, o, Y, a, b, M are each as defined in the description and the claims. The invention further relates to the use and preparation thereof, and to aqueous surfactant formulations comprising the mixtures, and to processes for producing mineral oil by means of Winsor type III microemulsion flooding, in which the aqueous surfactant formulation is injected into a mineral oil deposit through injection wells and crude oil is withdrawn from the deposit through production wells.

主权项

1. A process for producing mineral oil by means of Winsor type III microemulsion flooding, in which an aqueous surfactant formulation comprising a surfactant mixture comprising at least three ionic surfactants which differ in terms of the hydrocarbyl moiety (R1)(R2)—CH—CH2— and are of the general formula (I)where
R1 is a linear saturated or unsaturated aliphatic hydrocarbyl radical having 10 to 12 carbon atoms; R2 is a linear saturated or unsaturated aliphatic hydrocarbyl radical having 12 to 14 carbon atoms; where the R1 and R2 radicals are selected such that the at least 3 ionic surfactants of the general formula (I) give rise to hydrocarbyl radicals (R1)(R2)CHCH2— with 24 carbon atoms, 26 carbon atoms, and 28 carbon atoms, wherein the C24 surfactant of the general formula (I) is present within a range of from 40% to 60%, the C26 surfactant of the general formula (I) within a range of from 30% to 50% and the C28 surfactant of the general formula (I) within a range of from 7% to 20% based on the molar sum formed from the three surfactants; each A0 is independently ethylene, propylene or butylene; k is an integer from 1 to 99, X is a branched or unbranched hydrocarbylene group which has 1 to 10 carbon atoms and may be substituted by an OH group; o is0 or 1; Mb+ is a cation; Ya− is a sulfate group, sulfonate group, carboxylate group or phosphate group; b is 1, 2 or 3 and a is 1 or 2, said surfactant formulation having a total surfactant content of 0.05 to 5% by weight based on the total amount of the aqueous surfactant formulation is injected into a mineral oil deposit through at least one injection well for the purpose of lowering the interfacial tension between oil and water to <0.1 mN/m, and crude oil is withdrawn from the deposit through at least one production well.