1. A compound of formula I:
wherein R1, R2, R3 and R4 are independently selected from the group consisting of hydrogen, a C1 to C4 alkyl group and a moiety of formula \u2014CH2NHR5 provided that at least one R1, R2, R3 and R4 is a moiety of formula \u2014CH2NHR5 wherein R5 is a C8 to C28 aliphatic group.
2. The compound of claim 1 wherein R1, R2 and R4 are hydrogen and R3 is a moiety of formula \u2014CH2NHR5 wherein R5 is a C10 to C28 aliphatic group.
3. The compound of claim 2 wherein R5 is C10 to C18 aliphatic group.
4. The compound of claim 1 having the formula II:
wherein R6 and R7 are independently selected from the group consisting of hydrogen, a C1 to C4 alkyl group and a moiety of formula \u2014CH2NHR8 provided that at least one R6 and R7 is a moiety of formula \u2014CH2NHR8 wherein R8 is a C8 to C28 aliphatic group.
5. The compound of claim 4 wherein R6 is hydrogen.
6. The compound of claim 4, wherein R7 is hydrogen.
7. A process for preparing an aminomethyl-substituted imidazole compound comprising, reacting
(a) an imidazole compound having the formula III
wherein R11, R12, R13 and R14 are independently selected from the group consisting of hydrogen and a C1 to C4 alkyl group wherein at least one of R11, R12, R13 and R14 is hydrogen;
(b) formaldehyde or a formaldehyde-producing reagent; and
(c) an amine of having the formula
H2N\u2014R15
wherein R15 is a C8 to C28 aliphatic group.
8. The process of claim 7 wherein R15 is C10 to C18 aliphatic group.
9. The process of claim 7 wherein R11, R12, R13 and R14 are hydrogen.
10. A product produced according to the process of claim 7.
11. A lubricating oil composition comprising a major amount of an oil of lubricating viscosity and from 0.01 to 5 weight percent of one or more compounds having the formula
wherein R1, R2, R3 and R4 are independently selected from the group consisting of hydrogen, a C1 to C4 alkyl group and a moiety of formula \u2014CH2NHR5 provided that at least one R1, R2, R3 and R4 is a moiety of formula \u2014CH2NHR5 wherein R5 is a C8 to C28 aliphatic group.
12. The lubricating oil composition of claim 11 wherein R1, R2 and R4 are hydrogen and R3 is a moiety of formula \u2014CH2NHR5 wherein R5 is a C10 to C28 aliphatic group.
13. The lubricating oil composition of claim 11 wherein R5 is a C10 to C18 aliphatic group.
14. A lubricating oil additive concentrate comprising from 90 to 10 weight percent of a liquid organic diluent and from about 10 to 90 weight percent of one or more compounds having the formula
wherein R1, R2, R3 and R4 are independently selected from the group consisting of hydrogen, a C1 to C4 alkyl group and a moiety of formula \u2014CH2NHR5 provided that at least one R1, R2, R3 and R4 is a moiety of formula \u2014CH2NHR5 wherein R5 is a C8 to C28 aliphatic group.
15. The lubricating oil additive concentrate of claim 14 wherein R1, R2 and R4 are hydrogen and R3 is a moiety of formula \u2014CH2NHR5 wherein R5 is a C10 to C28 aliphatic group.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A surfactant mixture comprising at least three ionic surfactants which differ in terms of the hydrocarbyl moiety (R1)(R2)\u2014CH\u2014CH2\u2014 and are of the general formula (I)
where
R1 is a linear or branched, saturated or unsaturated aliphatic hydrocarbyl radical having 10 to 12 carbon atoms;
R2 is a linear or branched, saturated or unsaturated aliphatic hydrocarbyl radical having 12 to 14 carbon atoms;
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 is 0 or 1;
Mb+ is a cation;
Ya\u2212 is a sulfate group, sulfonate group, carboxylate group or phosphate group;
b is 1, 2 or 3 and
a is 1 or 2.
2. The surfactant mixture according to claim 1, wherein
R1 is a linear or branched, saturated or unsaturated aliphatic hydrocarbyl radical having 10 or 12 carbon atoms; and
R2 is a linear or branched, saturated or unsaturated aliphatic hydrocarbyl radical having 12 or 14 carbon atoms.
3. The surfactant mixture according to claim 1, wherein
R1 is a linear saturated or unsaturated aliphatic hydrocarbyl radical having 10 or 12 carbon atoms,
R2 is a linear saturated or unsaturated aliphatic hydrocarbyl radical having 12 or 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\u2014 with 24 carbon atoms, 26 carbon atoms and 28 carbon atoms.
4. The surfactant mixture according to claim 1, wherein k is an integer in the range from 4 to 50.
5. The surfactant mixture according to claim 1, wherein the (OX)oY1\u2212 radical in formula (I) is OS(O)2O, OCH2CH2S(O)2O\u2212, OCH2CH(OH)CH2S(O)2O\u2212, O(CH2)3S(O)2O\u2212, S(O)2O\u2212, CH2C(O)O\u2212 or CH2CH(R\u2032)C(O)O\u2212, where R\u2032 is hydrogen or an alkyl radical having 1 to 4 carbon atoms.
6. The surfactant mixture according to claim 1, wherein (OA)k in formula (I) represents n butyleneoxy, m propyleneoxy and I ethyleneoxy groups, where n+m+l=k.
7. The surfactant mixture according to claim 6, wherein the n butyleneoxy, m propyleneoxy and I ethyleneoxy groups are arranged in blocks.
8. The surfactant mixture according to claim 7, wherein the (R1)(R2)\u2014CH\u2014CH2\u2014 radical in formula (I) is followed, representing (OA)k, by a butyleneoxy block with n butyleneoxy groups, followed by a propyleneoxy block with m propyleneoxy groups, and finally an ethyleneoxy block with I ethyleneoxy groups.
9. The surfactant mixture according to claim 6, wherein m is an integer from 4 to 15 andor l is an integer of 0 to 25 andor n is an integer from 2 to 15.
10. The surfactant mixture according to claim 1, which further comprises surfactants of the formula
and of the formula
where R1, R2, A0, X, Ya\u2212, Mb+, k, o, a and b are each as defined for formula (I).
11. The surfactant mixture according to claim 10, wherein the proportion of surfactants of the formula (I) in relation to the sum of the amounts of surfactants of the formulae (I), (II) and (III) is in the range from 80% by weight to 99% by weight.
12. An aqueous surfactant formulation comprising a surfactant mixture according to claim 1, said surfactant formulation preferably having a total surfactant content of 0.05 to 5% by weight based on the total amount of the aqueous surfactant 1.0 formulation.
13. A process for producing mineral oil by means of Winsor type Ill microemulsion flooding, in which an aqueous surfactant formulation according to claim 12 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 mNm, and crude oil is withdrawn from the deposit through at least one production well.
14. A process for preparing a surfactant mixture according to claim 1, comprising the steps of:
(a) preparing Guerbet alcohols of the general formula (IV) (R1)(R2)\u2014CH\u2014CH2OH (IV), where R1 and R2 are each as defined in claims 1 to 11, by condensing a mixture of at least two primary alcohols of the formula R\u2014CH2\u2014CH2\u2014OH, where R is a linear or branched, saturated or unsaturated aliphatic hydrocarbyl radical having 10 to 12 carbon atoms,
(b) alkoxylating the alcohols obtained in process step (a),
(c) reacting the alcohol alkoxylates obtained in step (b) with a Ya\u2212 group, optionally to form a spacer group OX.
15. A method of using a surfactant mixture according to claim 1 in mineral oil production by means of Winsor type III microemulsion flooding.