CN112708411A - Oil displacement zwitterionic surfactant and polyether amine surfactant composition, and preparation method and application thereof - Google Patents

Abstract

The invention relates to a zwitterionic surfactant and polyether amine surfactant composition for oil displacement, a preparation method and application thereof, and mainly solves the problems that the existing surfactant is low in oil displacement efficiency, poor in temperature resistance and salt resistance, large in adsorption retention and incapable of meeting the oil displacement requirement of an oil reservoir. The invention adopts a surfactant composition, which comprises the following components: (1) a zwitterionic compound; (2) a polyetheramine surfactant; wherein the molar ratio of the zwitterionic compound to the polyether amine surfactant is 1 (0.01-50); the molecular general formula of the zwitterionic compound is shown in the formula (I), and the molecular general formula of the polyether amine surfactant is shown in the formula (II), so that the problem is solved well, and the zwitterionic compound can be used in oil fields to improve the yield of crude oil.

Description

Oil displacement zwitterionic surfactant and polyether amine surfactant composition, and preparation method and application thereof

Technical Field

The invention relates to a zwitterionic surfactant and polyether amine surfactant composition for oil displacement, a preparation method and application thereof

Background

The enhanced oil recovery technology, namely the Enhanced Oil Recovery (EOR) and Improved Oil Recovery (IOR) technology generally referred to abroad, can be summarized into six aspects of improving water flooding, chemical flooding, heavy oil thermal recovery, gas flooding, microbial oil recovery, physical oil recovery and the like. Currently, the enhanced oil recovery techniques that enter large-scale applications in mines are concentrated in three major categories, thermal recovery, gas flooding and chemical flooding. Chemical flooding is a strengthening measure for improving the recovery ratio by adding a chemical agent into an aqueous solution and changing the physicochemical property and rheological property of an injected fluid and the interaction characteristic with reservoir rocks, and is rapidly developed in China, mainly because the reservoir deposits in China have strong heterogeneity, the viscosity of the continental-phase crude oil is high, and the method is more suitable for chemical flooding in an EOR method.

Surfactants as an important component of chemical flooding can be classified into two major classes, namely ionic and nonionic, according to their chemical composition and molecular structure. The most anionic surfactant types are currently used in tertiary oil recovery studies, followed by nonionic and zwitterionic surfactants, and the least cationic surfactant is used. The results of oil displacement by using alkaline water, surfactant or alkaline water oil displacement and oil displacement by using zwitterionic surfactant are sequentially reported by US3927716, US4018281 and US4216097 of Mofu Petroleum company, the zwitterionic surfactant is carboxylic acid or sulfonate type betaine surfactant with different chain lengths, and the interfacial tension on crude oil in Texas south Texas is 10 in simulated saline with total mineralization of 62000-160000 mg/L and calcium and magnesium ions of 1500-18000 mg/L^-1～10^-4mN/m. For example, chinese patents CN 1528853, CN 1817431, CN 1066137 and the like sequentially report bisamide type cationic, fluorine-containing cationic and pyridyl-containing cationic gemini surfactants, but the use of cations in oil fields is limited due to the disadvantages of large adsorption loss, high cost and the like.

After the surfactants of different types are compounded with each other, the defects of a single surfactant can be overcome, and the advantages of each component are exerted, so that the oil displacement agent is endowed with more excellent performance. Chinese patent CN1458219A discloses a surfactant/polymer binary ultra-low interfacial tension composite flooding formula for tertiary oil recovery, wherein the used surfactant is petroleum sulfonate or an oil displacement agent compounded by petroleum sulfonate serving as a main agent, a diluent and other surfactants, the weight percentage of the components is 50-100% of petroleum sulfonate, 0-50% of alkyl sulfonate, 0-50% of carboxylate, 0-35% of alkyl aryl sulfonate and 0-20% of low-carbon alcohol, and the surfactant system is too complex. The United states Texas university patent US8211837 reports that branched long carbon alcohol is obtained by catalytic dimerization reaction of simple and cheap linear alcohol at high temperature, the branched long carbon alcohol is polymerized with propylene oxide and ethylene oxide and then is subjected to sulfuric acid esterification reaction, compared with an expensive sulfonate surfactant, a large hydrophilic group polyether sulfate surfactant is synthesized at low cost, the sulfate surfactant has excellent high-temperature stability under an alkaline condition due to the existence of large hydrophilic groups, 0.3 percent of branched alcohol polyether sulfate (C32-7PO-6EO sulfate) and 0.3 percent of internal olefin sulfonate (C20-24 IOS) saline solution are mixed with the same amount of crude oil at 85 ℃, and the solubilization parameter is 14. Patent US4370243 of meifu petroleum company reports an oil displacement system composed of oil-soluble alcohol, betaine sulfonate and quaternary ammonium salt, which can function as both a surfactant and a fluidity control agent, wherein the quaternary ammonium salt is a cationic surfactant with a lipophilic carbon chain length of 16-20, 2% octadecyl dihydroxyethyl propyl betaine sulfonate and 1.0% hexanol are used as oil displacement agents, after 1.9PV is injected, the crude oil can be 100% displaced, but the adsorption loss of the surfactant is as large as 6mg/g, and 2.0% tetraethylammonium bromide with a relatively low price is added as a sacrificial agent to reduce the adsorption capacity of the surfactant.

Research results at home and abroad show that the surfactant is limited in practical application as an oil displacement agent due to large use amount, high preparation cost and poor use effect of a single surfactant. The invention relates to an oil displacement surfactant composition with stable structure under oil reservoir conditions, an oil displacement agent, a preparation method and application in oil displacement.

Disclosure of Invention

One of the technical problems to be solved by the invention is that the surfactant in the prior art has poor solubilization capacity on crude oil, low oil displacement efficiency, poor temperature and salt resistance and large adsorption retention, and cannot meet the oil displacement requirement of a high-temperature and high-salt oil reservoir, and a novel surfactant composition for oil displacement is provided, so that an aqueous solution of the surfactant composition can well emulsify the crude oil, has strong solubilization capacity, has the maximum solubilization parameter of 16.6-20.5, and has the advantages of good temperature and salt resistance and low adsorption retention, thereby effectively improving the oil displacement efficiency of the crude oil, and having good application prospect of improving the recovery ratio.

The second technical problem to be solved by the present invention is to provide a method for preparing the surfactant composition described in the first technical problem.

The invention also provides an application of the surfactant composition in oil displacement, which solves one of the technical problems.

The fourth technical problem to be solved by the invention is the problem that the oil displacement agent system containing the surfactant in the prior art has poor crude oil capacity-increasing capability, low oil displacement efficiency, poor temperature resistance and salt resistance, large adsorption retention and can not meet the oil displacement requirement of a high-temperature and high-salt reservoir, and the invention provides a novel oil displacement agent, the water solution oil-water interfacial tension of which can reach 10^-3～10^-4mN/m, thereby effectively improving the oil displacement efficiency of crude oil and having good application prospect of improving the recovery ratio.

The fifth technical problem to be solved by the present invention is to provide a method for preparing an oil displacement agent corresponding to the fourth technical problem to be solved.

The sixth technical problem to be solved by the present invention is to provide an application of the oil displacement agent corresponding to the fourth technical problem to be solved.

In order to solve one of the above technical problems, the technical solution adopted by the present invention is as follows: a surfactant composition comprising the following components:

(1) a zwitterionic compound;

(2) a polyetheramine surfactant;

wherein the molar ratio of the zwitterionic compound to the polyether amine surfactant is 1 (0.01-50); the molecular general formula of the zwitterionic compound is shown as the formula (I):

in the formula (I), R₁And R₄Is hydrogen, C₂～C₃₂Alkyl or substituted alkyl of (CH R')_cOH、(CH R')_dCH₃One of phenyl, substituted phenyl or benzyl, R₂Is C₁～C₅Alkylene or substituted alkylene, X^-Is radical carboxylate, sulfonate, phosphate or sulfate radical, R₃Is hydrogen, C₂～C₃₂Alkyl or substituted alkyl (CHR')_eOH, halogen, amino, carboxylic acid group or sulfonic group, R 'and R' are independently selected from H, CH₃Or C₂H₅C is any integer of 1 to 4, d is any integer of 0 to 5, and e is any integer of 0 to 4.

The molecular general formula of the polyether amine surfactant is as follows:

in the formula (II), R₅Is C₈～C₃₀Or linear or branched, saturated or unsaturated alkyl or from C₄～C₂₀Saturated and unsaturated hydrocarbon radicals, straight-chain or branched, or cumyl (C)₆H₅C(CH₃)₂) Substituted benzene or naphthalene rings, or R₅Is abietylamine radical; r1, r2, r3 or r4 are independently selected from 0-50, but r1 and r2, and r3 and r4 cannot be 0 at the same time; s1 and s2 are independently selected from 0-100, but s1 and s2 cannot be 0 at the same time; y is R₆Z; y 'is R'₆Z′；R₆And R'₆Is independently selected from C₁～C₅At least one of alkylene or hydroxy-substituted alkylene of (a); z and Z' are independentlyIs selected from COOM and SO₃And one of N, M, N is selected from cation or cation group. In the above technical scheme, R₁Or R₄Preferably hydrogen, C₈～C₂₄The alkyl or substituted alkyl, methyl, ethyl, hydroxyethyl, hydroxypropyl, phenyl and benzyl.

In the above technical scheme, R₂X^-Preferably C₁～C₃Alkylene or substituted alkylene carboxylates, C₁～C₃Alkylene or substituted alkylene sulfonate.

In the above technical scheme, R₃Preferably hydrogen, C₈～C₂₄Hydrogen, methyl, ethyl, phenyl, hydroxyl, amino, carboxylic acid or sulfonic acid.

In the above technical scheme, R', R⁰Preferably H or CH₃。

In the above technical means, c is preferably 1 to 2, d is preferably 0 to 1, and e is preferably 0 to 1.

In the above embodiments, M, N is preferably a hydrogen ion, an alkali metal cation, or a compound represented by the formula NR₇(R₈)(R₉)(R₁₀) At least one of the groups shown.

In the above technical scheme, R₇、R₈、R₉、R₁₀Preferably H, (CHR)⁰)_fOH or (CHR)⁰)_gCH₃One kind of (1).

In the above technical scheme, R⁰Preferably H, CH₃Or C₂H₅One kind of (1).

In the above-described embodiment, f is preferably 1 to 2, and g is preferably 0 to 1.

In the above technical scheme, R₅Preferably C₁₂～C₂₄Or with a hydrocarbon or substituted hydrocarbon radical of₄～C₂₀Saturated and unsaturated hydrocarbon radicals, straight-chain or branched, or cumyl (C)₆H₅C(CH₃)₂) Substituted benzene or naphthalene rings, or R₅N is abietylamine radical.

The technical proposal is thatIn, R₆And R'₆Preferably C₁～C₃An alkylene group of (a).

In the above technical solution, r1+ r2 is preferably 1 to 10, r3+ r4 is preferably 1 to 10, and s1+ s2 is preferably 1 to 40.

In the above technical solution, the surfactant composition preferably further comprises the following components in parts by mole:

(3) a small molecule alcohol;

(4) a small molecule amine;

(5) salt;

(6) an inorganic base;

wherein the molar ratio of the zwitterionic compound, the polyether amine surfactant, the small molecular alcohol, the small molecular amine, the salt and the inorganic base is 1 (0.01-50): (0-20): 0-10); the small molecular alcohol is selected from C₁～C₈The fatty alcohol of (a); the small molecule amine is selected from C₁～C₈At least one of a primary amine, a secondary amine, or a tertiary amine; the salt is at least one of metal halide and hydroxyl substituted carboxylate; the inorganic base is at least one selected from alkali metal hydroxide, alkali metal carbonate or alkali metal bicarbonate.

In the technical scheme, the molar preferred ratio of the zwitterionic compound, the surfactant containing polyether segments, the micromolecular alcohol, the micromolecular amine, the salt and the inorganic base is 1 (0.02-30): 0-15): 0-5.

In the above technical scheme, the preferable small molecular alcohol is C₁～C₅The fatty alcohol of (1).

In the above technical scheme, the preferable small molecule amine is C₁～C₅The fatty amine of (1).

In the above technical solution, the metal halide is preferably an alkali metal halide, and is further preferably one of sodium chloride, potassium chloride, sodium bromide and potassium bromide; the hydroxyl-substituted carboxylate is preferably one of sodium glycolate and potassium glycolate.

In the above technical solution, the inorganic base is preferably an alkali metal hydroxide, carbonate or bicarbonate.

The oil-displacing surfactant composition can also comprise oil-displacing components commonly used in the field, such as oil-displacing polymers, oil-displacing foam agents, oil-displacing mineral substances (such as sodium chloride and potassium chloride), alkaline substances (such as sodium hydroxide, sodium carbonate, sodium bicarbonate, diethanolamine, triethanolamine and other micromolecular organic amines), and organic micromolecular auxiliaries, such as short-chain fatty alcohols, low-carbon-chain ketones, DMSO and the like.

The key active ingredients of the oil-displacing surfactant composition are (1) and (2), and those skilled in the art know that the oil-displacing surfactant composition can be supplied in various forms, such as a non-aqueous solid form, an aqueous paste form or an aqueous solution form, for convenience of transportation and storage or on-site use; the aqueous solution form comprises a form of preparing a concentrated solution by water and a form of directly preparing a solution with concentration required by on-site oil displacement, for example, a solution with the key active ingredient content of 0.005-0.6 wt% by weight is a form suitable for on-site oil displacement; the water is not particularly required, and can be deionized water or water containing inorganic mineral substances, and the water containing the inorganic mineral substances can be tap water, oil field formation water or oil field injection water.

To solve the second technical problem, the technical solution adopted by the present invention is as follows: a method for preparing the surfactant composition according to any one of the above-mentioned technical solutions to solve the technical problems, comprising the steps of:

(a) preparation of zwitterionic compound:

will be provided with

With ionizing agents X₀R₂Uniformly mixing the X in water or alcohol water for quaternization reaction to obtain an aqueous solution or an alcohol aqueous solution of the zwitterionic compound shown in the formula (I); wherein the alcohol accounts for 0-100 wt% of the alcohol aqueous solution in percentage by mass, and the alcohol is selected from C₁～C₅Fatty alcohol of (2), X₀Selected from chlorine, bromine or iodine;

(b) preparation of surfactant composition:

is catalyzed under alkaline conditionIn the presence of an agent, R₅NH₂Reacting with required amount of ethylene oxide, propylene oxide and ethylene oxide in sequence to obtain a polyether compound; mixing a desired amount of a polyether compound with the aqueous or aqueous alcoholic solution of the zwitterionic compound obtained in step (a) to obtain said surfactant composition;

or obtaining the surfactant composition by a second reaction:

② the polyether compound obtained in the step I and an ionizing agent Y₀R₆Z or Y₀R'₆Mixing Z' and alkali metal hydroxide or alkali metal alkoxide according to a molar ratio of 1 (0.1-20) to 0.1-20, reacting at a reaction temperature of 50-120 ℃ for 3-15 hours under stirring, adding the zwitterionic compound aqueous solution or alcohol aqueous solution obtained in the step (a) according to a required molar ratio, heating to 40-100 ℃, and stirring for 1-5 hours to obtain the surfactant composition; wherein, Y₀Selected from chlorine, bromine or iodine;

or: ② the polyether compound obtained in the step I and an ionizing agent Y₀R₆COOR₀Or Y₀R'₆COOR₀And alkali metal hydroxide or alkali metal alkoxide are mixed according to the molar ratio of 1 (0.1-20) to 0.1-20, the mixture is stirred and reacted at the reaction temperature of 50-120 ℃ for 3-15 hours, water is continuously added for saponification reaction, after refluxing for 1-10 hours, the zwitterionic compound aqueous solution or alcohol aqueous solution obtained in the step (a) is added according to the required molar ratio, the temperature is raised to 40-100 ℃, and the mixture is stirred for 1-5 hours, so that the required surfactant composition is obtained; wherein R is₀Is selected from C₁～C₈Alkyl group of (1).

In the above technical scheme, the ionizing agent X in the step (a)₀R₂X is preferably at least one of an alkali metal salt of 3-chloro-2-hydroxypropanesulfonic acid, an alkali metal salt of 2-chloroethanesulfonic acid, 1, 3-propanesultone, chloroacetic acid, and an alkali metal salt of chloroacetic acid.

In the above technical scheme, the small molecule alcohol in the step (a) is preferably C₁～C₄The fatty alcohol of (1).

In the above technical scheme, in the step (a)

And X₀R₂The preferable molar ratio of X is 1: 1-3.

In the above technical scheme, the reaction temperature in the step (b) is preferably 120 to 160 ℃, the basic catalyst is preferably at least one of potassium hydroxide or anhydrous potassium carbonate, and the pressure is preferably 0.30 to 0.60MPa gauge pressure.

In the above technical solution, the alkali metal hydroxide in the step (b) is preferably at least one of potassium hydroxide or sodium hydroxide, the molar ratio of the polyether compound to the ionizing agent and the alkali metal hydroxide or the alkali metal alkoxide is preferably 1 (2-10) to (2-10), and R is preferably 1₀Preferably C₁～C₄Alkyl group of (1).

Y₀R₆Examples of Z include, but are not limited to, chloroacetic acid, sodium chloroacetate, sodium 1-chloro-2-hydroxypropanesulfonate, and the like.

Y₀R₆Z⁰Examples of (d) are, but not limited to, chloroacetates (e.g., ethyl chloroacetate), bromoacetates (e.g., ethyl bromoacetate), and the like.

In order to solve the third technical problem, the technical scheme adopted by the invention is as follows: the application of the surfactant composition in any technical scheme for solving the technical problem in oil displacement in an oil field is disclosed.

In the technical scheme, the oil displacement agent can be applied according to the prior art, can be used independently, and can also be compounded with an oil field common auxiliary agent for use; as a preferable scheme: the total salinity of stratum saline water of the oil reservoir is preferably selected from 5000-200000 mg/L in the application, wherein Ca is²⁺+Mg²⁺10 to 15000mg/L, HCO ₃ ^-0 to 2000 mg/L; the viscosity of the crude oil is 1.0-200.0 mPa.s; the formation temperature is 50-120 ℃.

The oil displacement agent prepared by the invention shows synergistic interaction among the components, and shows the aspects of increasing surface activity, reducing critical micelle concentration, improving crude oil solubilizing capability and the like. Especially, the electrostatic action of the surfactants with opposite electric properties promotes the association between two surfactant ions with different charges, and the hydrophobic hydrocarbon chains of the two have certain hydrophobic action to promote different surfactant molecules to adopt a tighter arrangement mode, so that micelles are easily formed in a solution, and higher surface activity and lower critical micelle concentration than a single surfactant are generated. In addition, the preparation method of the oil displacement agent adopted by the invention has the advantage that the high-purity ionic surfactant is high in price and can be obtained only by complex purification steps such as extraction, column chromatography and the like, so that the preparation cost of the surfactant for oil displacement is greatly increased. Polyether and halogenated carboxylate or halogenated carboxylate are adopted to generate polyether carboxylate or polyether carboxylate under the catalysis of alkali metal hydroxide or alkali metal alkoxide, separation is not needed or saponification is directly carried out to obtain polyether carboxylate, a required amount of zwitterionic compound water or small molecular alcohol aqueous solution is added to be mixed, small molecular alcohol or amine in a system and a surfactant can form a composite membrane at an interface and are distributed to oil and water phases, the properties of an oil phase and a water phase are improved, the reduction of oil-water interfacial tension and the formation of microemulsion are facilitated, the generated inorganic salt has a promoting effect on the interfacial property and does not need to be removed, the excessive alkali metal hydroxide can neutralize acid substances in crude oil to form soap, the solubilizing capability of the surfactant on the crude oil is further improved, the oil washing efficiency of an oil displacement agent is improved, and the green production of the surfactant is realized.

The present invention refers to the total concentration of the components of the molecular formula (I) and the molecular formula (II) in the above technical scheme, when the content or concentration of the surfactant composition is referred to.

In order to solve the fourth technical problem, the invention adopts the technical scheme that: an oil displacement agent comprises the following components in parts by weight:

1)1 part of the surfactant composition according to any one of the above-mentioned means for solving the first technical problem or the surfactant composition obtained by the production method according to any one of the above-mentioned means for solving the second technical problem;

2)0 to 20 parts of a polymer and more than 0 part of a polymer;

3) 0-30 parts of alkali.

In the above technical solution, the polymer is not strictly limited, and may be various polymers for oil field oil recovery known to those skilled in the art, such as but not limited to at least one selected from xanthan gum, hydroxymethyl cellulose, hydroxyethyl cellulose, anionic polyacrylamide, temperature-resistant and salt-resistant modified polyacrylamide, hydrophobically associating polymer, and polymer microspheres.

In the technical scheme, the preferable molecular chain of the temperature-resistant and salt-resistant modified polyacrylamide comprises an acrylamide structural unit and a temperature-resistant and salt-resistant monomer structural unit, the molar ratio of the acrylamide structural unit to the temperature-resistant and salt-resistant monomer structural unit is (0.1-40) to 1, the viscosity average molecular weight is 800-2500 ten thousand, and further, the preferable molecular chain of the temperature-resistant and salt-resistant monomer is 2-acrylamido-2-methylpropanesulfonic acid; the molecular chain of the hydrophobic association polymer comprises an acrylamide structural unit, a temperature-resistant and salt-resistant monomer structural unit and a hydrophobic monomer structural unit, wherein the molar ratio of the acrylamide structural unit to the temperature-resistant and salt-resistant monomer structural unit to the hydrophobic monomer structural unit is 1: (0.1-40): (0.001 to 0.05) and a viscosity average molecular weight of 500 to 2500 ten thousand.

In the technical scheme, the hydrophobic association polymer is preferably copolymerized by acrylamide, a temperature-resistant salt-resistant monomer or a hydrophobic monomer; the temperature-resistant and salt-resistant modified polyacrylamide is preferably copolymerized by acrylamide and a temperature-resistant and salt-resistant monomer; the temperature-resistant and salt-resistant monomer or hydrophobic monomer may be at least one of monomers having a large side group or a rigid side group (e.g., styrenesulfonic acid, N-alkylmaleimide, acrylamido long-chain alkylsulfonic acid, long-chain alkylallyl dimethylammonium halide, 3-acrylamido-3-methylbutyric acid, etc.), monomers having a salt-resistant group (e.g., 2-acrylamido-2-methylpropanesulfonic acid), monomers having a hydrolysis-resistant group (e.g., N-alkylacrylamide), monomers having a group that inhibits hydrolysis of an amide group (e.g., N-vinylpyrrolidone), monomers having a hydrophobic group, etc.), which are well known to those skilled in the art, the temperature-resistant and salt-resistant monomer is preferably 2-acrylamido-2-methylpropanesulfonic acid, and the hydrophobic monomer is preferably 2-acrylamidododecyl sulfonic acid.

In the above technical scheme, the mole ratio of acrylamide to the temperature-resistant salt-resistant monomer to the hydrophobic monomer in the hydrophobic association polymer is preferably 1: (0.1-40): (0.001 to 0.05) and a viscosity average molecular weight of 500 to 2500 ten thousand; more preferably, the molar ratio of the acrylamide to the temperature-resistant salt-resistant monomer to the hydrophobic monomer is 1 to (0.1-20) to (0.001-0.01), and the viscosity average molecular weight is 1200-2200 ten thousand.

In the technical scheme, the molar preferred ratio of the acrylamide to the temperature-resistant salt-resistant monomer in the temperature-resistant salt-resistant modified polyacrylamide is (0.1-40) to 1.

In the above technical scheme, the hydrophobic association polymer is preferably formed by copolymerizing acrylamide, 2-acrylamido-2-methylpropanesulfonic acid and 2-acrylamidododecyl sulfonic acid, and the molar ratio of acrylamide, 2-acrylamido-2-methylpropanesulfonic acid and 2-acrylamidododecyl sulfonic acid is preferably 1: (0.1-40): (0.001 to 0.05), more preferably 1: (0.1 to 20): (0.001 to 0.01).

In the technical scheme, the temperature-resistant salt-resistant modified polyacrylamide is preferably prepared by copolymerizing acrylamide and 2-acrylamide-2-methylpropanesulfonic acid, the molar ratio of the acrylamide to the 2-acrylamide-2-methylpropanesulfonic acid is preferably (0.1-40): 1, and the viscosity average molecular weight of the modified polyacrylamide is preferably 800-2500 ten thousand.

In the above technical scheme, the alkali is an inorganic alkaline substance or an organic alkali.

In the above technical solution, the inorganic basic substance is preferably at least one of an alkali metal hydroxide, an alkaline earth metal hydroxide, and an alkali metal carbonate; it is further preferable that the alkali metal hydroxide is at least one selected from the group consisting of sodium hydroxide and potassium hydroxide, the alkaline earth metal hydroxide is at least one selected from the group consisting of magnesium hydroxide and calcium hydroxide, and the alkali metal carbonate is at least one selected from the group consisting of sodium carbonate and sodium bicarbonate.

In the above technical solution, the organic base preferably contains at least one of a primary amine group, a secondary amine group, a tertiary amine group, and a quaternary ammonium base in a molecule, and more preferably C₁～C₈At least one of short carbon chain organic amines, more preferably at least one of ethanolamine, diethanolamine, triethanolamine or triethylamine.

In the technical scheme, the mass ratio of the surfactant composition to the polymer to the alkali in the oil displacement agent is preferably 1 to (0.1-2): (0-5).

The key active ingredients of the oil-displacing agent composition of the present invention are the components 1), 2) and 3), and those skilled in the art know that various supply forms such as a non-aqueous solid form, an aqueous paste form, or an aqueous solution form can be adopted for convenience of transportation and storage or field use; the water solution form comprises a form of preparing a concentrated solution by using water and a form of directly preparing an oil displacement agent with the concentration required by on-site oil displacement; the water is not particularly required, and can be deionized water or water containing inorganic mineral substances, and the water containing the inorganic mineral substances can be tap water, oil field formation water or oil field injection water.

The oil displacement agent composition of the present invention may further contain oil recovery aids such as a foaming agent, small molecular organic substances (e.g., ethylene glycol monomethyl ether, ethylene glycol monobutyl ether, DMSO, etc.) and the like which are commonly used in the art.

In order to solve the fifth technical problem, the invention adopts the technical scheme that: a preparation method of the oil displacement agent in any one of the four technical solutions for solving the technical problems, comprising the following steps:

(a) preparation of zwitterionic compound:

will be provided with

With ionizing agents X₀R₂Uniformly mixing the X in water or alcohol water for quaternization reaction to obtain an aqueous solution or an alcohol aqueous solution of the zwitterionic compound shown in the formula (I); wherein, the concentration of the alcohol aqueous solution is as follows according to the mass percentage of the alcohol in the alcohol aqueous solution0 to 100 wt%, the alcohol is selected from C₁～C₅Fatty alcohol of (2), X₀Selected from chlorine, bromine or iodine;

(b) preparation of surfactant composition:

in the presence of an alkaline catalyst, R₅NH₂Reacting with required amount of ethylene oxide, propylene oxide and ethylene oxide in sequence to obtain a polyether compound; mixing a desired amount of a polyether compound with the aqueous or aqueous alcoholic solution of the zwitterionic compound obtained in step (a) to obtain said surfactant composition;

or obtaining the surfactant composition by a second reaction:

② the polyether compound obtained in the step I and an ionizing agent Y₀R₆Z or Y₀R'₆Mixing Z' and alkali metal hydroxide or alkali metal alkoxide according to a molar ratio of 1 (0.1-20) to 0.1-20, reacting at a reaction temperature of 50-120 ℃ for 3-15 hours under stirring, adding the zwitterionic compound aqueous solution or alcohol aqueous solution obtained in the step (a) according to a required molar ratio, heating to 40-100 ℃, and stirring for 1-5 hours to obtain the surfactant composition; wherein, Y₀Selected from chlorine, bromine or iodine;

or: ② the polyether compound obtained in the step I and an ionizing agent Y₀R₆COOR₀Or Y₀R'₆COOR₀And alkali metal hydroxide or alkali metal alkoxide are mixed according to the molar ratio of 1 (0.1-20) to 0.1-20, the mixture is stirred and reacted at the reaction temperature of 50-120 ℃ for 3-15 hours, water is continuously added for saponification reaction, after refluxing for 1-10 hours, the zwitterionic compound aqueous solution or alcohol aqueous solution obtained in the step (a) is added according to the required molar ratio, the temperature is raised to 40-100 ℃, and the mixture is stirred for 1-5 hours, so that the required surfactant composition is obtained; wherein R is₀Is selected from C₁～C₈Alkyl group of (1).

(c) And (b) uniformly mixing the surfactant composition obtained in the step (b) with a polymer and alkali according to the required amount by mass to obtain the oil-displacing agent.

In the above technical solution, the preferable solution is: the ionizationReagent X₀R₂X is preferably at least one of an alkali metal salt of 3-chloro-2-hydroxypropanesulfonic acid, an alkali metal salt of 2-chloroethanesulfonic acid, 1, 3-propanesultone, chloroacetic acid, and an alkali metal salt of chloroacetic acid sulfonating agent, and the alcohol is preferably selected from C₁～C₄The fatty alcohol of (a); the above-mentioned

And X₀R₂The preferable molar ratio of X is 1: 1-3; the method comprises the following steps: the reaction temperature is preferably 120-160 ℃, the pressure is preferably 0.3-0.6 MPa gauge pressure, and the alkaline catalyst is preferably at least one of potassium hydroxide or anhydrous potassium carbonate; the second step is as follows: the alkali metal hydroxide is preferably at least one of potassium hydroxide or sodium hydroxide, and the molar ratio of the polyether compound to the ionizing agent and the alkali metal hydroxide or the alkali metal alkoxide is preferably 1 (2-10): 2-10), and X₀And Y₀Preferably one of chlorine or bromine, R₀Preferably C₁～C₄Alkyl group of (1).

In order to solve the sixth technical problem, the invention adopts the technical scheme that: the application of the oil displacement agent comprises the following steps:

(1) mixing the oil displacement agent in any one of the four technical schemes for solving the technical problems with water to obtain an oil displacement system;

(2) and contacting the oil displacement system with an oil-bearing stratum under the conditions that the oil displacement temperature is 25-150 ℃ and the total salinity is more than 500 mg/L of simulated formation water, and displacing the crude oil in the oil-bearing stratum.

In the technical scheme, the oil-displacing agent can be obtained by mixing the components according to required amount by adopting various conventional mixing methods, and is dissolved by water according to required concentration when used for displacing oil to obtain the oil-displacing agent for displacing oil; and according to the concentration of the oil displacement agent, the components in the oil displacement composition are respectively dissolved in water to obtain the oil displacement agent for oil displacement. The water used in the preparation can be tap water, river water, seawater and oil field formation water.

In the above technical scheme, the oil displacementThe agent can be applied according to the prior art, can be used independently, and can also be compounded with common oil field additives for use; as a preferable scheme: the total salinity of stratum saline water of the oil reservoir is preferably selected from 5000-200000 mg/L in the application, wherein Ca is²⁺+Mg²⁺10 to 15000mg/L, HCO ₃ ^-0 to 2000 mg/L; the viscosity of the crude oil is 1.0-200.0 mPa.s; the formation temperature is 50-120 ℃.

The invention adopts a physical simulation displacement evaluation method to evaluate the effect, and the specific evaluation method comprises the following steps: drying the core at constant temperature to constant weight, and measuring the gas logging permeability of the core; calculating the pore volume of the simulated oil field stratum water saturated core, recording the volume of saturated crude oil by using the crude oil saturated core at the oil displacement temperature, pumping the stratum water at the speed of 0.2mL/min, driving until the water content reaches 100%, calculating the recovery ratio of the crude oil improved by water drive, then transferring the oil displacement agent obtained in the step (c) at the speed of 0.15mL/min, driving the oil displacement agent to the water content of 100% at the speed of 0.2mL/min, and calculating the percentage of the recovery ratio of the crude oil improved on the basis of the water drive.

The method for testing the interfacial tension comprises the following steps: (1) presetting the temperature to the temperature required by the measurement, and waiting for the temperature to be stable; (2) injecting external phase liquid, filling the centrifuge tube, injecting internal phase liquid, removing bubbles, and tightly covering; (3) the centrifuge tube is arranged in a rotating shaft of the instrument, the rotating speed is set, and a microscope is adjusted to enable inner phase liquid drops or bubbles in the visual field to be very clear; (4) reading and calculating, and calculating the interfacial tension according to the formula (1):

γ＝0.25ω²r³Δ ρ (L/D ≧ 4) formula (1);

wherein γ is the interfacial tension (mN. m)^-1) Δ ρ is the two-phase density difference (Kg. m)^-3.) Omega is angular velocity (rad · s)^-1) R is the minor axis radius (m) of the droplet, L is the major axis (centrifuge tube axial) diameter, and D is the minor axis (centrifuge tube radial) diameter.

The method for testing the static adsorption capacity comprises the following steps: fully mixing a simulated saline solution of a surfactant and an adsorbate according to a certain liquid-solid ratio, oscillating for a certain time at a set temperature and frequency, cooling, performing centrifugal separation, taking supernatant, measuring the concentration of effective components of the surfactant, and calculating the adsorption capacity of the surfactant, wherein the formula (2) is shown:

Γ ═ W (Co × a-Ce)/m formula (2);

wherein gamma is static adsorption capacity (mg/g), W is weight (g) of the surfactant solution, Co is initial concentration (mg/g) of the surfactant solution calculated according to commodity content, A is effective content (%) of the surfactant product, effective concentration (mg/g) of the Ce surfactant solution after adsorption, and m is mass (g) of the adsorbent.

The test method of the solubilization parameter of the invention comprises the following steps: (1) firstly, sealing the tip of a 5mL temperature-resistant glass pipette, and intercepting the required length for later use; (2) preparing a surfactant solution with a certain concentration, measuring a certain volume of aqueous solution by using a pipettor, adding the aqueous solution into a glass pipettor with a sealed tip, simultaneously recording the mass of the added solution by using an analytical balance, adding a certain amount of crude oil or simulated oil (the oil-water ratio is determined according to the experimental requirements) according to the same method, and recording the volume and the mass; recording the water phase and oil phase scales; (3) after the sample is added, sealing the upper opening of the glass pipette; (4) uniformly mixing by adopting vortex oscillation or rotation; (5) standing for a period of time at a set temperature, continuously shaking to gradually reach equilibrium, photographing to record the change of a phase state along with time, and calculating a solubilization parameter, wherein the formula is shown in (3):

wherein SP is a solubilization parameter, V_S、V_O、V_WThe volume of surfactant, the volume of crude oil solubilized by the surfactant, and the volume of water solubilized by the surfactant, respectively.

The test method of the carboxylation degree and the sulfonation degree comprises the following steps: an analytical method for determining the end point of titration by indicating the change of potential difference (or electrode potential) during titration analysis with a potential measuring device. The measurement is performed by using the relationship between the electrode potential of the electrode and the activity of the component to be measured.

Halmin cation solution as titrant

S^－+Hyamine＝S-Hyamine

Under alkaline conditions (pH 11), both carboxylate and sulfonate surfactants exist in salt form and are able to react with hallisin cations, and the amount of both surfactants can be measured using hallisin cation solution as a titrant. The carboxylation degree or sulfonation degree of the anionic surfactant can be measured by adopting a two-phase potentiometric titration method and taking hallisin cationic solution as a titrant and judging equivalent potential by a potentiometric titrator.

Accurately weighing 5.0g of surfactant sample solution to be measured, sampling 3-4 parts in parallel each time, recording the weighed weight W_S(g) Respectively adding 40mL of distilled water, and adjusting the pH value of each parallel sample to be about 11.00 by using 0.2M NaOH standard solution; adding 10mL of ethanol and 10mL of methyl isobutyl ketone (MIBK) into the solution with the adjusted pH value in sequence, titrating by adopting 0.004M hamming 1622 standard solution, and recording the volume V of the consumed halmin_H(mL). The degree of carboxylation or sulfonation of the surfactant samples was calculated using the following formula. Where Mw is the molecular weight of the surfactant sample to be tested.

The surfactant composition prepared by the invention is used in an amount of 0.01-0.15 wt% in percentage by mass, and can be used for the formation with the temperature of 50-120 ℃, the degree of mineralization of 5000-200000 Mg/L and Mg²⁺+Ca ²⁺20 to 12000 mg/l, HCO₃ ^-The dynamic interfacial tension value between the surfactant aqueous solution and the crude oil is measured to be 0-2000 mg/L of oilfield water and crude oil and can reach 10^-2～10^-4The mN/m low interfacial tension, the static adsorption capacity less than 2mg/g, 4 wt% of surfactant can well emulsify the crude oil, the maximum solubilization parameter is 20.5, and a better technical effect is achieved.

The oil displacement agent is used for simulated brine and crude oil with the formation temperature of 50-120 ℃ and the mineralization degree of 5000-200000 mg/L, and the dosage is 0.01-0.15 wt% of surfactant composition and 0E0.3 wt% of the polymer and 0-1.2 wt% of the alkali form an oil displacement agent, the apparent viscosity of the oil displacement agent aqueous solution is measured, and the dynamic interfacial tension value between the oil displacement agent aqueous solution and the oil field dehydrated crude oil can reach 10^-2～10^-4The mN/m is evaluated in a physical simulation displacement laboratory, and the oil displacement agent can improve the crude oil recovery rate on the basis of water displacement by 27.74 percent to the maximum extent, so that a better technical effect is achieved.

Drawings

The zwitterionic compound and the surfactant containing polyether fragment prepared by the invention can be applied to a Nicolet-5700 spectrometer and subjected to infrared spectrum analysis (the scanning range is 4000-400 cm) by total reflection (ATR)^-1) And determining the chemical structure of the tested sample so as to achieve infrared characterization of the compound.

FIG. 1 is a reaction solution HPLC chart of (N-carboxymethyl-N-octadecyl-N-methyl) phenylammonium inner salt prepared in [ example 1 ]. Evaporative light detector (ELSD), Xcharge C18 chromatography column (2.1 × 150mm, 5 μm); gradient elution is carried out by acetonitrile-0.1% trifluoroacetic acid water solution, the flow rate is 1.0mL/min, and the column temperature is 30 ℃. Wherein 1 is solvent group peak, 2 is unreacted tertiary amine (N-octadecyl-N-methylaniline), and 3 is (N-carboxymethyl-N-octadecyl-N-methyl) phenyl ammonium inner salt.

FIG. 2 is an infrared spectrum of (N-carboxymethyl-N-octadecyl-N-methyl) phenyl ammonium inner salt. Wherein, 2918.4cm^-1And 2850.4cm^-1Is a characteristic peak of C-H stretching of methyl and methylene, 1629.9cm^-1Is C ═ O stretching vibration absorption peak, 1546.8cm^-1And 1602.8cm^-1Is the stretching vibration peak of benzene ring, 1465.1cm^-1Is a C-N bending vibration absorption peak, 1167.0cm^-1And 1239.1cm^-1Is a C-N stretching vibration peak of 700.0-800.0 cm^-1Is the in-plane rocking absorption peak of CH plane in the benzene ring.

FIG. 3 is a graph of oil-water interfacial tension of 0.15% surfactant after aging for various periods of time.

Fig. 4 is a flow chart of an indoor core displacement experiment.

The invention is further illustrated by the following examples.

Detailed Description

[ example 1 ]

(a) Preparation of (N-carboxymethyl-N-octadecyl-N-methyl) phenylammonium inner salt

359.0 g (1 mol) of N-octadecyl-N-methylaniline, 174.8 g (1.5 mol) of sodium chloroacetate, and 750 g of a 50 wt% aqueous ethanol solution were mixed in a 2000 ml four-necked flask equipped with a mechanical stirrer, a thermometer, and a reflux condenser, and the mixture was heated to reflux for 8 hours to stop the reaction. A small amount of the reaction solution was taken for HPLC analysis, and the ratio of (N-carboxymethyl-N-octadecyl-N-methyl) phenylammonium inner salt to N-octadecyl-N-methylaniline was 96.7:3.3, as shown in FIG. 1. Dissolving ethyl acetate for desalting for multiple times, removing organic solvent to obtain zwitterionic surfactant, and performing infrared spectrum analysis (scan range 4000-400 cm) by total reflection (ATR) with Nicolet-5700 infrared spectrometer^-1) The infrared spectrum is shown in figure 2. The remaining samples were left untreated and were ready for use.

(b) Preparation of surfactant composition S01

Z₁＝Z₂＝CH₂COOH.HN(CH₂CH₂OH)₂；r₁+r₂＝4，s₁+s₂＝15，r₃+r₄＝3。

Adding 261 g (1 mol) of dodecylaniline, 5.9 g of sodium hydroxide and 11.9 g of anhydrous potassium carbonate into a 5L pressure reactor provided with a stirring device, heating to 80-90 ℃, starting a vacuum system, dehydrating for 1 hour under high vacuum, then replacing for 3-4 times with nitrogen, adjusting the reaction temperature of the system to 110 ℃, slowly introducing 178.2 g (4.05 mol) of ethylene oxide, controlling the pressure to be less than or equal to 0.50MPa, after the reaction of the ethylene oxide is finished, slowly introducing 881.6 g (15.2 mol) of propylene oxide at 150 ℃, controlling the pressure to be less than or equal to 0.60MPa, and after the reaction of the propylene oxide is finished, adjusting the temperature to 140 ℃, and slowly introducing 134.2 g (3.05 mol) of ethylene oxide. After the reaction is finished, the temperature is reduced to 90 ℃, low-boiling-point substances are removed in vacuum, and after cooling, neutralization and dehydration are carried out, 1394.4 g of dodecylaniline polyoxyethylene (4), polyoxypropylene (15), polyoxyethylene (3) ether are obtained, and the yield is 96.9%.

In a 5000 ml four-neck flask equipped with a mechanical stirrer, a thermometer and a reflux condenser, 719.5 g (0.5 mol) of dodecylaniline polyoxyethylene (4) polyoxypropylene (15) polyoxyethylene (3) ether, 235.0 g (2.0 mol) of sodium chloroacetate and 800 ml of toluene/benzene (v/v ═ 1) were mixed, and the mixture was heated to reflux reaction for 8 hours. After the reaction, all reaction solutions were acidified, washed with saturated brine 3 times, and toluene/benzene was distilled off under reduced pressure, and the obtained product was subjected to carboxylation of 190.4% using halmin cation solution as a titrant using a mertler T90 autopotentiometric titrator, and 1500g of water, 126.0 g (1.2 mol) of diethanolamine, 83.4 g (0.2 mol) of an aqueous ethanol solution of (N-carboxymethyl-N-octadecyl-N-methyl) phenylammonium inner salt were added, and uniformly mixed to obtain the desired surfactant composition S01.

[ example 2 ]

(a) Preparation of (N-carboxymethyl-N-carboxymethyloxyethyl-N-dodecyl) phenylammonium inner salt

359.0 g (1 mol) of N-dodecyl-N-hydroxyethyl aniline, 60.0 g (1.5 mol) of sodium hydroxide and 500 ml of benzene are mixed in a 5000 ml four-neck flask provided with a mechanical stirring device, a thermometer and a reflux condenser tube, the mixture is heated to 50 ℃, 174.8 g (1.5 mol) of sodium chloroacetate is added into a reaction bottle for four times, the mixture is heated to reflux reaction for 6 hours after the addition, the solvent benzene is evaporated under reduced pressure, 1500g of water is added into the mixture after the mixture is cooled to room temperature, the mixture is uniformly stirred, the mixture is heated to 75 ℃, 116.5 g (1.0 mol) of sodium chloroacetate is added into the reaction bottle for three times, the reaction is continued for 5 hours, and the reaction is stopped. A small amount of reaction liquid is taken for HPLC analysis, the ratio of (N-carboxymethyl-N-carboxymethyl oxyethyl-N-dodecyl) phenyl ammonium inner salt to N-dodecyl-N-hydroxyethyl aniline is 89.6:8.4, and the rest samples are not processed.

(b) Preparation of surfactant composition S02

Wherein r is₁+r₂＝5，s₁+s₂＝5，r₃+r₄＝3。

325 g (1 mol) of icosaediamine, 2.3 g of potassium hydroxide and 8.4 g of anhydrous potassium carbonate are added into a 2L pressure reactor provided with a stirring device, a vacuum system is started when the temperature is heated to 80-90 ℃, the dehydration is carried out for 1 hour under high vacuum, then nitrogen is used for replacing for 3-4 times, the reaction temperature of the system is adjusted to 120 ℃, 222.2 g (5.05 mol) of ethylene oxide is slowly introduced, the pressure is controlled to be less than or equal to 0.60MPa, the temperature is adjusted to 130 ℃ after the reaction of the ethylene oxide, 295.8 g (5.1 mol) of propylene oxide is slowly introduced, the pressure is controlled to be less than or equal to 0.60MPa, and the temperature is adjusted to 140 ℃ after the reaction of the propylene oxide, 134.2 g (3.05 mol) of ethylene oxide is slowly introduced. After the reaction, the temperature is reduced to 90 ℃, low-boiling-point substances are removed in vacuum, and neutralization and dehydration are carried out after cooling, so that 925.4 g of the icosapolyoxyethylene (5) polyoxypropylene (5) polyoxyethylene (3) ether are obtained, and the yield is 95.7%.

Icosanediamine polyoxyethylene (5) polyoxypropylene (5) polyoxyethylene (3) ether 478.5 g (0.5 mol), 160 g (4 mol) sodium hydroxide, 589.5 g (3 mol) sodium 3-chloro-2-hydroxypropanesulfonate and 800 ml toluene/benzene (v/v ═ 2) were mixed in a 5000 ml four-neck flask equipped with a mechanical stirrer, thermometer and reflux condenser, and heated to 85 ℃ for reaction for 9 hours. Cooling, taking 50 g of uniform reaction liquid, acidifying with 20 wt% hydrochloric acid, separating water and inorganic salt, evaporating to remove the solvent, adopting a Mettler company T90 automatic potentiometric titrator, taking a Heimemin cation solution as a titrant, and measuring the sulfonation degree to be 175.8% through potentiometric drop. . The solvent was distilled off from the remaining untreated reaction solution, 600 g of water, 80.0 g (2.0 mol) of sodium hydroxide, and an aqueous solution containing 630.0 g (1.5 mol) of (N-carboxymethyl-N-carboxymethyloxyethyl-N-dodecyl) phenylammonium inner salt were added, and stirring was continued at 40 ℃ for 4 hours to obtain the desired surfactant composition S02.

[ example 3 ]

(a) Preparation of (N-carboxymethyl-N-dodecyl-N-methyl) phenyl ammonium inner salt

274.0 g (1 mol) of N-dodecyl-N-methylaniline, 139.8 g (1.2 mol) of sodium chloroacetate and 500g of 5 wt% aqueous isopropanol were mixed in a 2000 ml four-necked flask equipped with a mechanical stirrer, a thermometer and a reflux condenser, and the mixture was heated to reflux for 6 hours to stop the reaction. Taking a small amount of reaction liquid for HPLC analysis, wherein the ratio of (N-carboxymethyl-N-dodecyl-N-methyl) phenyl ammonium inner salt to N-dodecyl-N-methylaniline is 94.7:6.3, and the rest samples are not processed for later use.

(b) Preparation of surfactant composition S03

R₅Is CH₃(CH₂)₇CH＝CH(CH₂)₈；Z₁＝Z₂＝CH₂COONa r₁+r₂＝3，s₁+s₂＝12，r₃+r₄＝4。

Adding 267.0 g (1 mol) of 9-ene-octadecylamine and 9.5 g of potassium hydroxide into a 5L pressure reactor provided with a stirring device, heating to 80-90 ℃, starting a vacuum system, dehydrating for 1 hour under high vacuum, then replacing for 3-4 times with nitrogen, adjusting the reaction temperature of the system to 110 ℃, slowly introducing 132.9 g (3.02 mol) of ethylene oxide, controlling the pressure to be less than or equal to 0.50MPa, after the reaction of the ethylene oxide is finished, slowly introducing 701.8 g (12.1 mol) of propylene oxide at 150 ℃, controlling the pressure to be less than or equal to 0.60MPa, and after the reaction of the propylene oxide is finished, adjusting the temperature to 130 ℃, and slowly introducing 178.2 g (4.05 mol) of ethylene oxide. After the reaction is finished, the temperature is reduced to 90 ℃, low-boiling-point substances are removed in vacuum, and neutralization and dehydration are carried out after cooling, so that 1230.3 g of 9-ene octadecylamine polyoxyethylene (3), polyoxypropylene (12) polyoxyethylene (4) ether are obtained, and the yield is 96.8%.

Introducing nitrogen into a 5000 ml reaction bottle provided with a mechanical stirring device, a thermometer and a reflux condenser tube to remove moisture, adding 635.5 g (0.5 mol) of 9-ene-octadecylamine polyoxyethylene (3) polyoxypropylene (12) polyoxyethylene (4) ether and 108.0 g (2.0 mol) of sodium methoxide under the protection of nitrogen, slowly dripping 162.8 g (1.5 mol) of methyl chloroacetate, controlling the reaction temperature to be 65 ℃ for reacting for 8 hours, cooling, adding 1000 g of water and 50 g of methanol, and continuously heating until reflux reaction is carried out for 5 hours. Cooling, taking 50 g of uniform reaction liquid, acidifying with 20 wt% hydrochloric acid, evaporating methanol, adding 100 g of benzene, mixing, removing a water layer, washing with saturated saline solution for 3 times, decompressing, evaporating benzene, and measuring the carboxylation degree to be 185.6% by adopting a Mettler company T90 automatic potentiometric titrator and using a Helminum cation solution as a titrant. The remaining untreated reaction solution was added 1280 g of water, an aqueous isopropanol solution containing 166.1 g (0.5 mol) of the inner salt of (N-carboxymethyl-N-dodecyl-N-methyl) phenylammonium and mixed well to obtain the desired surfactant composition S03.

[ example 4 ]

(a) Preparation of (N-carboxymethyl-N, N-dimethyl) -4-hexadecyl phenyl ammonium inner salt

345.0 g (1 mol) of N, N-dimethyl- (4-hexadecyl) aniline, 128.2 g (1.1 mol) of sodium chloroacetate and 600 g of a 15 wt% aqueous isopropanol solution were mixed in a 2000-ml four-neck flask equipped with a mechanical stirrer, a thermometer and a reflux condenser, and the mixture was heated to reflux for 9 hours to stop the reaction. A small amount of the reaction solution was subjected to HPLC analysis, the ratio of (N-carboxymethyl-N, N-dimethyl) -4-hexadecylphenylammonium inner salt to N, N-dimethyl- (4-hexadecyl) aniline was 91.2:8.8, and the remaining samples were left untreated and kept for future use.

(b) Preparation of surfactant composition S04

Wherein r is₁+r₂＝0，s₁+s₂＝5，r₃+r₄＝15。

325 g (1 mol) of icosanediamine, 2.3 g of potassium hydroxide and 8.4 g of anhydrous potassium carbonate are added into a 2L pressure reactor provided with a stirring device, a vacuum system is started when the temperature is heated to 80-90 ℃, dehydration is carried out for 1 hour under high vacuum, then nitrogen is used for replacing for 3-4 times, the reaction temperature of the system is adjusted to 130 ℃, 295.8 g (5.1 mol) of propylene oxide is slowly introduced, the pressure is controlled to be less than or equal to 0.60MPa, and 664.4 g (15.1 mol) of ethylene oxide is slowly introduced when the reaction of the propylene oxide is finished. After the reaction is finished, the temperature is reduced to 90 ℃, low-boiling-point substances are removed in vacuum, neutralization and dehydration are carried out after cooling, 1201.1 g of the icosapolyoxypropylene (5) polyoxyethylene (15) ether are obtained, and the yield is 94.2%.

Icosanediamine polyoxypropylene (5) polyoxyethylene (15) ether 637.5 g (0.5 mol) was mixed with 200 g (5 mol) sodium hydroxide, 589.5 g (3 mol) sodium 3-chloro-2-hydroxypropanesulfonate and 800 ml toluene/benzene (v/v ═ 2) in a 5000 ml four-neck flask equipped with a mechanical stirrer, thermometer and reflux condenser, and heated to 85 ℃ for 8 hours. Cooling, taking 50 g of uniform reaction liquid, acidifying with 20 wt% hydrochloric acid, separating water and inorganic salt, evaporating to remove the solvent, adopting a Mettler company T90 automatic potentiometric titrator, taking a Heimemin cation solution as a titrant, and measuring the sulfonation degree to be 168.7% through potentiometric dropping. The remaining untreated reaction solution was distilled off the solvent, 600 g of water, an aqueous isopropanol solution containing 806.0 g (2.0 mol) of the inner salt of (N-carboxymethyl-N, N-dimethyl) -4-hexadecylphenylammonium were added, and stirring was continued at 40 ℃ for 4 hours to obtain the desired surfactant composition S04.

[ example 5 ]

(a) Preparation of (N- (2-hydroxy-3-propanesulfonic acid) -N-methyl-N-hexadecyl) -4-methylphenyl ammonium inner salt

345.0 g (1 mol) of N-hexadecyl-N-methyl-4-methylaniline, 357.3 g (1.8 mol) of sodium 3-chloro-2-hydroxypropanesulfonate and 800 g of a 25 wt% aqueous ethanol solution were mixed in a 2000-ml four-necked flask equipped with a mechanical stirrer, a thermometer and a reflux condenser, and the mixture was heated to reflux reaction for 12 hours to stop the reaction. A small amount of the reaction solution was subjected to HPLC analysis, the ratio of (N- (2-hydroxy-3-propanesulfonic acid) -N-methyl-N-hexadecyl) -4-methylphenylammonium inner salt to N-hexadecyl-N-methyl-4-methylaniline was 87.5:12.5, and the remaining sample was left untreated and was used for future use.

(b) Preparation of surfactant composition S05

R₅Is C₁₄H₂₉；Z₁＝Z₂＝CH₂COONa r₁+r₂＝3，s₁+s₂＝12，r₃+r₄＝4。

Adding 213 g (1 mol) of tetradecylamine and 8.2 g of potassium hydroxide into a 5L pressure reactor provided with a stirring device, heating to 80-90 ℃, starting a vacuum system, dehydrating for 1 hour under high vacuum, then replacing for 3-4 times with nitrogen, adjusting the reaction temperature of the system to 110 ℃, slowly introducing 132.9 g (3.02 mol) of ethylene oxide, controlling the pressure to be less than or equal to 0.50MPa, after the reaction of the ethylene oxide is finished, slowly introducing 701.8 g (12.1 mol) of propylene oxide at 150 ℃, controlling the pressure to be less than or equal to 0.60MPa, and after the reaction of the propylene oxide is finished, adjusting the temperature to 130 ℃, and slowly introducing 178.2 g (4.05 mol) of ethylene oxide. After the reaction is finished, the temperature is reduced to 90 ℃, low-boiling-point substances are removed in vacuum, neutralization and dehydration are carried out after cooling, 1158.6 g of decatetramine polyoxyethylene (3), polyoxypropylene (12) and polyoxyethylene (4) ether are obtained, and the yield is 95.2%.

Introducing nitrogen into a 5000 ml reaction bottle provided with a mechanical stirring pipe, a thermometer and a reflux condenser pipe to remove water vapor, adding 608.5 g (0.5 mol) of tetradecylamine polyoxyethylene (3), polyoxypropylene (12) polyoxyethylene (4) ether and 108.0 g (2.0 mol) of sodium methoxide under the protection of nitrogen, slowly dripping 162.8 g (1.5 mol) of methyl chloroacetate, controlling the reaction temperature to be 65 ℃ for reacting for 8 hours, cooling, adding 1000 g of water and 50 g of methanol, and continuously heating until the reflux reaction is carried out for 5 hours. Cooling, taking 50 g of uniform reaction liquid, acidifying with 20 wt% hydrochloric acid, evaporating methanol, adding 100 g of benzene, mixing, removing a water layer, washing with saturated saline solution for 3 times, decompressing, evaporating benzene, and measuring the carboxylation degree to be 180.2% by adopting a Mettler company T90 automatic potentiometric titrator and taking a Halmin cation solution as a titrant. The remaining untreated reaction solution was added with 1000 g of water, 10.5 g (0.1 mol) of diethanolamine, and an aqueous ethanol solution containing 36.2 g (0.05 mol) of an inner salt of (N- (2-hydroxy-3-propanesulfonic acid) -N-methyl-N-hexadecyl) -4-methylphenylammonium, and stirred at 45 ℃ for 3 hours to obtain the desired surfactant composition S05.

[ example 6 ]

(a) Preparation of (N-carboxymethyl-N, N-dimethyl) phenyl ammonium inner salt

121.0 g (1 mol) of N, N-dimethylaniline, 139.8 g (1.2 mol) of sodium chloroacetate and 500g of a 5 wt% aqueous isopropanol solution were mixed in a 2000-ml four-necked flask equipped with a mechanical stirrer, a thermometer and a reflux condenser, and the mixture was heated to reflux for 8 hours to stop the reaction. And (3) taking a small amount of reaction liquid for HPLC analysis, wherein the ratio of the (N-carboxymethyl-N, N-dimethyl) phenyl ammonium inner salt to the N, N-dimethylaniline is 95.1:4.9, and the rest samples are not processed for later use.

(b) Preparation of surfactant composition S06

R₅Is CH₃(CH₂)₇CH＝CH(CH₂)₈；Z₁＝Z₂＝CH₂COONa r₁+r₂＝3，s₁+s₂＝12，r₃+r₄＝4。

Adding 267.0 g (1 mol) of 9-ene-octadecylamine and 9.5 g of potassium hydroxide into a 5L pressure reactor provided with a stirring device, heating to 80-90 ℃, starting a vacuum system, dehydrating for 1 hour under high vacuum, then replacing for 3-4 times with nitrogen, adjusting the reaction temperature of the system to 110 ℃, slowly introducing 132.9 g (3.02 mol) of ethylene oxide, controlling the pressure to be less than or equal to 0.50MPa, after the reaction of the ethylene oxide is finished, slowly introducing 701.8 g (12.1 mol) of propylene oxide at 150 ℃, controlling the pressure to be less than or equal to 0.60MPa, and after the reaction of the propylene oxide is finished, adjusting the temperature to 130 ℃, and slowly introducing 178.2 g (4.05 mol) of ethylene oxide. After the reaction is finished, the temperature is reduced to 90 ℃, low-boiling-point substances are removed in vacuum, and neutralization and dehydration are carried out after cooling, so that 1230.3 g of 9-ene octadecylamine polyoxyethylene (3), polyoxypropylene (12) polyoxyethylene (4) ether are obtained, and the yield is 96.8%.

Introducing nitrogen into a 5000 ml reaction bottle provided with a mechanical stirring device, a thermometer and a reflux condenser tube to remove moisture, adding 635.5 g (0.5 mol) of 9-ene-octadecylamine polyoxyethylene (3) polyoxypropylene (12) polyoxyethylene (4) ether and 108.0 g (2.0 mol) of sodium methoxide under the protection of nitrogen, slowly dripping 162.8 g (1.5 mol) of methyl chloroacetate, controlling the reaction temperature to be 65 ℃ for reacting for 8 hours, cooling, adding 1000 g of water and 50 g of methanol, and continuously heating until reflux reaction is carried out for 5 hours. Cooling, taking 50 g of uniform reaction liquid, acidifying with 20 wt% hydrochloric acid, evaporating methanol, adding 100 g of benzene, mixing, removing a water layer, washing with saturated saline solution for 3 times, decompressing, evaporating benzene, and measuring the carboxylation degree to be 185.6% by adopting a Mettler company T90 automatic potentiometric titrator and using a Helminum cation solution as a titrant. The remaining untreated reaction solution was added 1200 g of water, an aqueous isopropanol solution containing 3.6 g (0.02 mol) of the inner salt of (N-carboxymethyl-N, N-dimethyl) phenylammonium, and mixed well to obtain the desired surfactant composition S06.

[ example 7 ]

(a) Preparation of (N-carboxymethyl-N, N-diethyl) phenyl ammonium inner salt

144.0 g (1 mol) of N, N-diethylaniline, 151.5 g (1.3 mol) of sodium chloroacetate, and 500g of a 15 wt% aqueous solution of isopropanol were mixed in a 2000 ml four-necked flask equipped with a mechanical stirrer, a thermometer, and a reflux condenser, and the mixture was heated to reflux reaction for 8 hours to stop the reaction. And (3) taking a small amount of reaction liquid for HPLC analysis, wherein the ratio of the (N-carboxymethyl-N, N-diethyl) phenyl ammonium inner salt to the N, N-diethylaniline is 92.5:7.5, and the rest samples are not processed for later use.

(b) Preparation of surfactant composition S07

R₅Is CH₃(CH₂)₇CH＝CH(CH₂)₈；Z₁＝Z₂＝CH₂COONa r₁+r₂＝3，s₁+s₂＝12，r₃+r₄＝4。

Adding 267.0 g (1 mol) of 9-ene-octadecylamine and 9.5 g of potassium hydroxide into a 5L pressure reactor provided with a stirring device, heating to 80-90 ℃, starting a vacuum system, dehydrating for 1 hour under high vacuum, then replacing for 3-4 times with nitrogen, adjusting the reaction temperature of the system to 110 ℃, slowly introducing 132.9 g (3.02 mol) of ethylene oxide, controlling the pressure to be less than or equal to 0.50MPa, after the reaction of the ethylene oxide is finished, slowly introducing 701.8 g (12.1 mol) of propylene oxide at 150 ℃, controlling the pressure to be less than or equal to 0.60MPa, and after the reaction of the propylene oxide is finished, adjusting the temperature to 130 ℃, and slowly introducing 178.2 g (4.05 mol) of ethylene oxide. After the reaction is finished, the temperature is reduced to 90 ℃, low-boiling-point substances are removed in vacuum, and neutralization and dehydration are carried out after cooling, so that 1230.3 g of 9-ene octadecylamine polyoxyethylene (3), polyoxypropylene (12) polyoxyethylene (4) ether are obtained, and the yield is 96.8%.

Introducing nitrogen into a 5000 ml reaction bottle provided with a mechanical stirring device, a thermometer and a reflux condenser tube to remove moisture, adding 635.5 g (0.5 mol) of 9-ene-octadecylamine polyoxyethylene (3) polyoxypropylene (12) polyoxyethylene (4) ether and 108.0 g (2.0 mol) of sodium methoxide under the protection of nitrogen, slowly dripping 162.8 g (1.5 mol) of methyl chloroacetate, controlling the reaction temperature to be 65 ℃ for reacting for 8 hours, cooling, adding 1000 g of water and 50 g of methanol, and continuously heating until reflux reaction is carried out for 5 hours. Cooling, taking 50 g of uniform reaction liquid, acidifying with 20 wt% hydrochloric acid, evaporating methanol, adding 100 g of benzene, mixing, removing a water layer, washing with saturated saline solution for 3 times, decompressing, evaporating benzene, and measuring the carboxylation degree to be 185.6% by adopting a Mettler company T90 automatic potentiometric titrator and using a Helminum cation solution as a titrant. The remaining untreated reaction solution was added 1200 g of water, an aqueous isopropanol solution containing 10.3 g (0.05 mole) of the inner salt of (N-carboxymethyl-N, N-diethyl) phenylammonium, and mixed well to give the desired surfactant composition S07.

[ example 8 ]

(a) Preparation of (N-carboxymethyl-N-methyl-N-ethyl) phenylammonium inner salt

130.0 g (1 mol) of N-methyl-N-ethylaniline, 151.5 g (1.3 mol) of sodium chloroacetate, and 500g of a 15 wt% aqueous solution of isopropanol were mixed in a 2000-ml four-necked flask equipped with a mechanical stirrer, a thermometer, and a reflux condenser, and the mixture was heated to reflux reaction for 6.5 hours, and the reaction was stopped. And (3) taking a small amount of reaction liquid for HPLC analysis, wherein the ratio of (N-methyl-N-ethyl) phenyl ammonium inner salt to N-methyl-N-ethylaniline is 93.7:6.3, and the rest samples are not processed for later use.

(b) Surfactant composition S08 was prepared

R₅Is CH₃(CH₂)₇CH＝CH(CH₂)₈；Z₁＝Z₂＝CH₂COONa r₁+r₂＝3，s₁+s₂＝12，r₃+r₄＝4。

Adding 267.0 g (1 mol) of 9-ene-octadecylamine and 9.5 g of potassium hydroxide into a 5L pressure reactor provided with a stirring device, heating to 80-90 ℃, starting a vacuum system, dehydrating for 1 hour under high vacuum, then replacing for 3-4 times with nitrogen, adjusting the reaction temperature of the system to 110 ℃, slowly introducing 132.9 g (3.02 mol) of ethylene oxide, controlling the pressure to be less than or equal to 0.50MPa, after the reaction of the ethylene oxide is finished, slowly introducing 701.8 g (12.1 mol) of propylene oxide at 150 ℃, controlling the pressure to be less than or equal to 0.60MPa, and after the reaction of the propylene oxide is finished, adjusting the temperature to 130 ℃, and slowly introducing 178.2 g (4.05 mol) of ethylene oxide. After the reaction is finished, the temperature is reduced to 90 ℃, low-boiling-point substances are removed in vacuum, and neutralization and dehydration are carried out after cooling, so that 1230.3 g of 9-ene octadecylamine polyoxyethylene (3), polyoxypropylene (12) polyoxyethylene (4) ether are obtained, and the yield is 96.8%.

Introducing nitrogen into a 5000 ml reaction bottle provided with a mechanical stirring device, a thermometer and a reflux condenser tube to remove moisture, adding 635.5 g (0.5 mol) of 9-ene-octadecylamine polyoxyethylene (3) polyoxypropylene (12) polyoxyethylene (4) ether and 108.0 g (2.0 mol) of sodium methoxide under the protection of nitrogen, slowly dripping 162.8 g (1.5 mol) of methyl chloroacetate, controlling the reaction temperature to be 65 ℃ for reacting for 8 hours, cooling, adding 1000 g of water and 50 g of methanol, and continuously heating until reflux reaction is carried out for 5 hours. Cooling, taking 50 g of uniform reaction liquid, acidifying with 20 wt% hydrochloric acid, evaporating methanol, adding 100 g of benzene, mixing, removing a water layer, washing with saturated saline solution for 3 times, decompressing, evaporating benzene, and measuring the carboxylation degree to be 185.6% by adopting a Mettler company T90 automatic potentiometric titrator and using a Helminum cation solution as a titrant. The remaining untreated reaction solution was added with 1200 g of water, an aqueous isopropanol solution containing 18.8 g (0.1 mol) of the inner salt of (N-methyl-N-ethyl) phenylammonium, and mixed well to obtain the desired surfactant composition S08.

[ example 9 ]

The same as in example 1, except that the alcohol solvent was distilled off under reduced pressure at the end of the reaction in the step (a), to obtain the desired surfactant composition S09.

[ example 10 ]

(a) Preparation of (N-carboxymethyl-N-octadecyl-N-methyl) phenylammonium inner salt

359.0 g (1 mol) of N-octadecyl-N-methylaniline, 174.8 g (1.5 mol) of sodium chloroacetate, and 750 g of a 50 wt% aqueous ethanol solution were mixed in a 2000 ml four-necked flask equipped with a mechanical stirrer, a thermometer, and a reflux condenser, and the mixture was heated to reflux for 8 hours to stop the reaction. A small amount of the reaction solution was taken for HPLC analysis, and the ratio of (N-carboxymethyl-N-octadecyl-N-methyl) phenylammonium inner salt to N-octadecyl-N-methylaniline was 96.7:3.3, as shown in FIG. 1. Dissolving ethyl acetate for desalting for multiple times, removing organic solvent to obtain zwitterionic surfactant, and performing infrared spectrum analysis (scan range 4000-400 cm) by liquid membrane method with Nicolet-5700 infrared spectrometer^-1) The infrared spectrum is shown in figure 2. The remaining samples were left untreated and were ready for use.

(b) Preparation of surfactant composition S10

Z₁＝Z₂＝H；r₁+r₂＝4，s₁+s₂＝15，r₃+r₄＝3。

Adding 261 g (1 mol) of dodecylaniline, 5.9 g of sodium hydroxide and 11.9 g of anhydrous potassium carbonate into a 5L pressure reactor provided with a stirring device, heating to 80-90 ℃, starting a vacuum system, dehydrating for 1 hour under high vacuum, then replacing for 3-4 times with nitrogen, adjusting the reaction temperature of the system to 110 ℃, slowly introducing 178.2 g (4.05 mol) of ethylene oxide, controlling the pressure to be less than or equal to 0.50MPa, after the reaction of the ethylene oxide is finished, slowly introducing 881.6 g (15.2 mol) of propylene oxide at 150 ℃, controlling the pressure to be less than or equal to 0.60MPa, and after the reaction of the propylene oxide is finished, adjusting the temperature to 140 ℃, and slowly introducing 134.2 g (3.05 mol) of ethylene oxide. After the reaction is finished, the temperature is reduced to 90 ℃, low-boiling-point substances are removed in vacuum, and after cooling, neutralization and dehydration are carried out, 1394.4 g of dodecylaniline polyoxyethylene (4), polyoxypropylene (15), polyoxyethylene (3) ether are obtained, and the yield is 96.9%.

Dodecylaniline polyoxyethylene (4) polyoxypropylene (15) polyoxyethylene (3) ether 5.8 g (0.004 mol), 200 g water, 126.0 g (1.2 mol) diethanolamine, 83.4. g (0.2 mol) aqueous ethanol of (N-carboxymethyl-N-octadecyl-N-methyl) phenyl ammonium inner salt, and mixing them uniformly to obtain the desired surfactant composition S10.

[ example 11 ]

Performance experiments of the surfactant composition as an oil displacement agent.

Simulated water with different salt contents is prepared, and the composition is shown in table 1. Crude oil was used for the experiments in the oil field, the properties of which are shown in table 2, after dehydration. .

The phase state experiment can well reflect the solubilizing capability of the surfactant to the crude oil, and the solubilizing parameters of the surfactant to the crude oil and the optimal salt content of the surfactant are obtained. The experimental process is as follows: first, 4.0 wt.% aqueous solutions of different salt contents (1) were prepared^#～9^#Simulated water), adding 2.5mL of the solution into a 5mL pipette with one end sealed, adding 2.5mL of dehydrated crude oil (the volume ratio of oil to water is 1:1), sealing the upper end, recording the initial volume of oil and water, fully mixing, placing the mixture into a stainless steel sealed container, placing the container in an oven, standing at constant temperature until the volume of each phase is not changed, recording the volume of each phase, calculating the solubilization parameter of the surfactant to the crude oil, and taking the salinity when the solubilization parameter is maximum as the optimal salt content, wherein the result is shown in Table 2.

The static adsorption test is mainly based on the research of adsorption loss amount of the surfactant on the formation rock core, and the economy and the formability of the surfactant synthesized in the embodiment in the field application of improving the crude oil recovery rate are explored. The experimental process is as follows: mixing 3g of simulated saline solution of the surfactant and 1g of clay-containing quartz sand, oscillating for 24 hours at a set temperature, cooling, performing centrifugal separation, taking supernatant, measuring the concentration of effective components of the surfactant by using a TOC method, and calculating the adsorption capacity of the surfactant in unit mg/g, wherein the result is shown in Table 3. Wherein, the clay-containing quartz sand comprises the following components: 10 wt% of kaolin and 90 wt% of 100-200 mesh quartz sand.

Dissolving the surfactant composition in corresponding simulated water, and measuring the oil content of the crude oilThe results of the water interfacial tension are shown in Table 4. Filling 0.15 wt% surfactant composition simulated saline solution into a 20 ml anbei bottle, sealing, placing into an oven, measuring oil-water interfacial tension after different aging times, and finding that the oil-water interfacial tension can still maintain 10 after aging^-3～10^-4Ultra low values of mN/m are shown in FIG. 3. The oil-water interfacial tension (IFT) was measured by a model TX500 rotary droplet interfacial tensiometer manufactured by Texas university, USA and a SVT 20 high temperature rotary droplet interfacial tensiometer manufactured by Dataphysics.

[ COMPARATIVE EXAMPLE 1 ]

Octadecyl benzyl methyl betaine

Octadecyl dimethyl betaine

The same as in example 1 except that (N-carboxymethyl-N-octadecyl-N-methyl) phenylammonium inner salt was replaced with commercially available octadecyl benzyl methyl betaine or octadecyl dimethyl betaine, the rest was the same, to give surfactant compositions S11 and S12. The performance test was carried out as in example 11, and the results are shown in Table 5.

TABLE 1

TABLE 2

TABLE 3

TABLE 4

TABLE 5

[ example 12 ]

(a) Preparation of (N-carboxymethyl-N-octadecyl-N-methyl) phenylammonium inner salt

359.0 g (1 mol) of N-octadecyl-N-methylaniline, 174.8 g (1.5 mol) of sodium chloroacetate, and 750 g of a 50 wt% aqueous ethanol solution were mixed in a 2000 ml four-necked flask equipped with a mechanical stirrer, a thermometer, and a reflux condenser, and the mixture was heated to reflux for 8 hours to stop the reaction. A small amount of the reaction solution was taken for HPLC analysis, and the ratio of (N-carboxymethyl-N-octadecyl-N-methyl) phenylammonium inner salt to N-octadecyl-N-methylaniline was 96.7:3.3, as shown in FIG. 1. Dissolving ethyl acetate for desalting for multiple times, removing organic solvent to obtain zwitterionic surfactant, and performing infrared spectrum analysis (scan range 4000-400 cm) by total reflection (ATR) with Nicolet-5700 infrared spectrometer^-1) The infrared spectrum is shown in figure 2. The remaining samples were left untreated and were ready for use.

(b) Preparation of surfactant composition S01

Z₁＝Z₂＝CH₂COOH.HN(CH₂CH₂OH)₂；r₁+r₂＝4，s₁+s₂＝15，r₃+r₄＝3。

Adding 261 g (1 mol) of dodecylaniline, 5.9 g of sodium hydroxide and 11.9 g of anhydrous potassium carbonate into a 5L pressure reactor provided with a stirring device, heating to 80-90 ℃, starting a vacuum system, dehydrating for 1 hour under high vacuum, then replacing for 3-4 times with nitrogen, adjusting the reaction temperature of the system to 110 ℃, slowly introducing 178.2 g (4.05 mol) of ethylene oxide, controlling the pressure to be less than or equal to 0.50MPa, after the reaction of the ethylene oxide is finished, slowly introducing 881.6 g (15.2 mol) of propylene oxide at 150 ℃, controlling the pressure to be less than or equal to 0.60MPa, and after the reaction of the propylene oxide is finished, adjusting the temperature to 140 ℃, and slowly introducing 134.2 g (3.05 mol) of ethylene oxide. After the reaction is finished, the temperature is reduced to 90 ℃, low-boiling-point substances are removed in vacuum, and after cooling, neutralization and dehydration are carried out, 1394.4 g of dodecylaniline polyoxyethylene (4), polyoxypropylene (15), polyoxyethylene (3) ether are obtained, and the yield is 96.9%.

In a 5000 ml four-neck flask equipped with a mechanical stirrer, a thermometer and a reflux condenser, 719.5 g (0.5 mol) of dodecylaniline polyoxyethylene (4) polyoxypropylene (15) polyoxyethylene (3) ether, 235.0 g (2.0 mol) of sodium chloroacetate and 800 ml of toluene/benzene (v/v ═ 1) were mixed, and the mixture was heated to reflux reaction for 8 hours. After the reaction, all reaction solutions were acidified, washed with saturated brine 3 times, and toluene/benzene was distilled off under reduced pressure, and the obtained product was subjected to carboxylation of 190.4% using halmin cation solution as a titrant using a mertler T90 autopotentiometric titrator, and 1500g of water, 126.0 g (1.2 mol) of diethanolamine, 83.4 g (0.2 mol) of an aqueous ethanol solution of (N-carboxymethyl-N-octadecyl-N-methyl) phenylammonium inner salt were added, and uniformly mixed to obtain the desired surfactant composition S01.

Simulated water with different salt contents is prepared, and the composition is shown in table 1. Crude oil was used for the experiments in the oil field, the properties of which are shown in table 2, after dehydration.

The phase state experiment can well reflect the solubilizing capability of the surfactant to the crude oil, and the solubilizing parameters of the surfactant to the crude oil and the optimal salt content of the surfactant are obtained. The experimental process is as follows: first, 4.0 wt% aqueous surfactant solutions (1) of different salt contents were prepared^#～9^#Simulation ofWater), 2.5mL is added into a 5mL pipette with one end sealed, 2.5mL of dehydrated crude oil (the volume ratio of oil to water is 1:1) is added, after the upper end is sealed, the initial volume of oil and water is recorded, after the mixture is fully mixed, the mixture is placed into a stainless steel sealed container and placed in an oven for standing at constant temperature until the volume of each phase is not changed, the volume of each phase is recorded, the solubilization parameter of the surfactant to the crude oil is calculated, and the salinity when the solubilization parameter is maximum is the optimal salt content, and the result is shown in table 2.

Mixing 3g of surfactant simulated aqueous solution and 1g of clay-containing quartz sand, oscillating for 24h, cooling, centrifuging, taking supernatant to measure the adsorption capacity in mg/g, and obtaining the result shown in Table 3. Wherein, the adsorption capacity is determined by a TOC method, and the clay-containing quartz sand comprises the following components: 10 wt% of kaolin and 90 wt% of 100-200 mesh quartz sand.

(c) Performance test of oil-displacing agent

(1) Preparation of oil-displacing agent aqueous solution

Preparing an S01 surfactant composition, a modified polyacrylamide polymer (P1, the molar ratio of the copolymer AM/AMPS is 1/0.05, and the viscosity average molecular weight is 2500 ten thousand) and an aqueous solution of sodium carbonate by using 11# simulated water, and mixing and diluting the aqueous solution according to a required ratio to obtain a uniform oil displacement agent.

(2) The viscosity and the oil-water interfacial tension of the oil-displacing agent were measured and compared with those of S01 and P1, as shown in Table 6. The apparent viscosity was measured by a model HAAKE MARS III rotational rheometer, and the interfacial tension was measured by a model TX500 rotational drop interfacial tension meter, manufactured by texas university, usa.

(3) And drying the artificial core at constant temperature to constant weight, measuring the average diameter and the length of the core, weighing the dry weight of the core, and measuring the gas logging permeability of the core. The pore volume was tested with the above simulated brine saturated core. And (4) recording the volume of the saturated crude oil by using the oil field dehydrated crude oil saturated core. At the temperature of 75 ℃, 11# simulation water is used for driving until the water content of produced liquid reaches 100%, the recovery ratio of the crude oil improved by water driving is calculated, after 0.3PV (core pore volume) oil displacement agent is injected, the water is driven until the water content reaches 100%, the percentage of the crude oil improved on the basis of water driving is calculated, and meanwhile, the comparison with the injection of the same PV surfactant and polymer is shown in the table 6. The flow of the simulated core displacement test used is shown in fig. 4. The viscosity of the dehydrated crude oil is 2.5 mPa.s.

[ example 13 ]

(a) Preparation of (N-carboxymethyl-N-carboxymethyloxyethyl-N-dodecyl) phenylammonium inner salt

359.0 g (1 mol) of N-dodecyl-N-hydroxyethyl aniline, 60.0 g (1.5 mol) of sodium hydroxide and 500 ml of benzene are mixed in a 5000 ml four-neck flask provided with a mechanical stirring device, a thermometer and a reflux condenser tube, the mixture is heated to 50 ℃, 174.8 g (1.5 mol) of sodium chloroacetate is added into a reaction bottle for four times, the mixture is heated to reflux reaction for 6 hours after the addition, the solvent benzene is evaporated under reduced pressure, 1500g of water is added into the mixture after the mixture is cooled to room temperature, the mixture is uniformly stirred, the mixture is heated to 75 ℃, 116.5 g (1.0 mol) of sodium chloroacetate is added into the reaction bottle for three times, the reaction is continued for 5 hours, and the reaction is stopped. A small amount of reaction liquid is taken for HPLC analysis, the ratio of (N-carboxymethyl-N-carboxymethyl oxyethyl-N-dodecyl) phenyl ammonium inner salt to N-dodecyl-N-hydroxyethyl aniline is 89.6:8.4, and the rest samples are not processed.

(b) Preparation of surfactant composition S02

Wherein r is₁+r₂＝5，s₁+s₂＝5，r₃+r₄＝3。

325 g (1 mol) of icosaediamine, 2.3 g of potassium hydroxide and 8.4 g of anhydrous potassium carbonate are added into a 2L pressure reactor provided with a stirring device, a vacuum system is started when the temperature is heated to 80-90 ℃, the dehydration is carried out for 1 hour under high vacuum, then nitrogen is used for replacing for 3-4 times, the reaction temperature of the system is adjusted to 120 ℃, 222.2 g (5.05 mol) of ethylene oxide is slowly introduced, the pressure is controlled to be less than or equal to 0.60MPa, the temperature is adjusted to 130 ℃ after the reaction of the ethylene oxide, 295.8 g (5.1 mol) of propylene oxide is slowly introduced, the pressure is controlled to be less than or equal to 0.60MPa, and the temperature is adjusted to 140 ℃ after the reaction of the propylene oxide, 134.2 g (3.05 mol) of ethylene oxide is slowly introduced. After the reaction, the temperature is reduced to 90 ℃, low-boiling-point substances are removed in vacuum, and neutralization and dehydration are carried out after cooling, so that 925.4 g of the icosapolyoxyethylene (5) polyoxypropylene (5) polyoxyethylene (3) ether are obtained, and the yield is 95.7%.

Icosanediamine polyoxyethylene (5) polyoxypropylene (5) polyoxyethylene (3) ether 478.5 g (0.5 mol), 160 g (4 mol) sodium hydroxide, 589.5 g (3 mol) sodium 3-chloro-2-hydroxypropanesulfonate and 800 ml toluene/benzene (v/v ═ 2) were mixed in a 5000 ml four-neck flask equipped with a mechanical stirrer, thermometer and reflux condenser, and heated to 85 ℃ for reaction for 9 hours. Cooling, taking 50 g of uniform reaction liquid, acidifying with 20 wt% hydrochloric acid, separating water and inorganic salt, evaporating to remove the solvent, adopting a Mettler company T90 automatic potentiometric titrator, taking a Heimemin cation solution as a titrant, and measuring the sulfonation degree to be 175.8% through potentiometric drop. . The solvent was distilled off from the remaining untreated reaction solution, 600 g of water, 80.0 g (2.0 mol) of sodium hydroxide, and an aqueous solution containing 630.0 g (1.5 mol) of (N-carboxymethyl-N-carboxymethyloxyethyl-N-dodecyl) phenylammonium inner salt were added, and stirring was continued at 40 ℃ for 4 hours to obtain the desired surfactant composition S02. Phase and static adsorption experiments were carried out as in [ example 12 ] and the results are shown in tables 2 and 3.

(c) Performance test of oil-displacing agent

The same as [ example 12 ] except that S02 was used instead of S01, a hydrophobically associating polymer P2 (copolymer AM/AMPS/2-acrylamidododecylsulfonic acid molar ratio 1/0.45/0.002, viscosity average molecular weight 1750 ten thousand) was used instead of the modified polyacrylamide polymer (P1, copolymer AM/AMPS molar ratio 1/0.05, viscosity average molecular weight 2500 ten thousand), and diethanolamine was used instead of sodium carbonate and 9# simulated water to prepare an oil displacement agent aqueous solution at a temperature of 110 ℃ and a crude oil viscosity of 1.9mpa.s, and the results are shown in table 7.

[ example 14 ]

(a) Preparation of (N-carboxymethyl-N-dodecyl-N-methyl) phenyl ammonium inner salt

274.0 g (1 mol) of N-dodecyl-N-methylaniline, 139.8 g (1.2 mol) of sodium chloroacetate and 500g of 5 wt% aqueous isopropanol were mixed in a 2000 ml four-necked flask equipped with a mechanical stirrer, a thermometer and a reflux condenser, and the mixture was heated to reflux for 6 hours to stop the reaction. Taking a small amount of reaction liquid for HPLC analysis, wherein the ratio of (N-carboxymethyl-N-dodecyl-N-methyl) phenyl ammonium inner salt to N-dodecyl-N-methylaniline is 94.7:6.3, and the rest samples are not processed for later use.

(b) Preparation of surfactant composition S03

R₅Is CH₃(CH₂)₇CH＝CH(CH₂)₈；Z₁＝Z₂＝CH₂COONa r₁+r₂＝3，s₁+s₂＝12，r₃+r₄＝4。

Adding 267.0 g (1 mol) of 9-ene-octadecylamine and 9.5 g of potassium hydroxide into a 5L pressure reactor provided with a stirring device, heating to 80-90 ℃, starting a vacuum system, dehydrating for 1 hour under high vacuum, then replacing for 3-4 times with nitrogen, adjusting the reaction temperature of the system to 110 ℃, slowly introducing 132.9 g (3.02 mol) of ethylene oxide, controlling the pressure to be less than or equal to 0.50MPa, after the reaction of the ethylene oxide is finished, slowly introducing 701.8 g (12.1 mol) of propylene oxide at 150 ℃, controlling the pressure to be less than or equal to 0.60MPa, and after the reaction of the propylene oxide is finished, adjusting the temperature to 130 ℃, and slowly introducing 178.2 g (4.05 mol) of ethylene oxide. After the reaction is finished, the temperature is reduced to 90 ℃, low-boiling-point substances are removed in vacuum, and neutralization and dehydration are carried out after cooling, so that 1230.3 g of 9-ene octadecylamine polyoxyethylene (3), polyoxypropylene (12) polyoxyethylene (4) ether are obtained, and the yield is 96.8%.

Introducing nitrogen into a 5000 ml reaction bottle provided with a mechanical stirring device, a thermometer and a reflux condenser tube to remove moisture, adding 635.5 g (0.5 mol) of 9-ene-octadecylamine polyoxyethylene (3) polyoxypropylene (12) polyoxyethylene (4) ether and 108.0 g (2.0 mol) of sodium methoxide under the protection of nitrogen, slowly dripping 162.8 g (1.5 mol) of methyl chloroacetate, controlling the reaction temperature to be 65 ℃ for reacting for 8 hours, cooling, adding 1000 g of water and 50 g of methanol, and continuously heating until reflux reaction is carried out for 5 hours. Cooling, taking 50 g of uniform reaction liquid, acidifying with 20 wt% hydrochloric acid, evaporating methanol, adding 100 g of benzene, mixing, removing a water layer, washing with saturated saline solution for 3 times, decompressing, evaporating benzene, and measuring the carboxylation degree to be 185.6% by adopting a Mettler company T90 automatic potentiometric titrator and using a Helminum cation solution as a titrant. The remaining untreated reaction solution was added 1280 g of water, an aqueous isopropanol solution containing 166.1 g (0.5 mol) of the inner salt of (N-carboxymethyl-N-dodecyl-N-methyl) phenylammonium and mixed well to obtain the desired surfactant composition S03. Phase and static adsorption experiments were carried out as in [ example 12 ] and the results are shown in tables 2 and 3.

(c) Performance test of oil-displacing agent

The same as [ example 12 ] except that S03 was used instead of S01, a hydrophobically associating polymer (P3, molar ratio of co-AM/AMPS/2-acrylamidododecylsulfonic acid 1/0.35/0.0015, viscosity average molecular weight 2055 ten thousand) was used instead of the modified polyacrylamide polymer (P1, molar ratio of co-AM/AMPS 1/0.05, viscosity average molecular weight 2500 ten thousand), diethanolamine was used instead of sodium carbonate, 12# simulated water was used to prepare an oil displacement agent aqueous solution at 90 ℃ and crude oil viscosity 2.1mpa.s, and the results are shown in table 7.

[ example 15 ]

(a) Preparation of (N-carboxymethyl-N, N-dimethyl) -4-hexadecyl phenyl ammonium inner salt

345.0 g (1 mol) of N, N-dimethyl- (4-hexadecyl) aniline, 128.2 g (1.1 mol) of sodium chloroacetate and 600 g of a 15 wt% aqueous isopropanol solution were mixed in a 2000-ml four-neck flask equipped with a mechanical stirrer, a thermometer and a reflux condenser, and the mixture was heated to reflux for 9 hours to stop the reaction. A small amount of the reaction solution was subjected to HPLC analysis, the ratio of (N-carboxymethyl-N, N-dimethyl) -4-hexadecylphenylammonium inner salt to N, N-dimethyl- (4-hexadecyl) aniline was 91.2:8.8, and the remaining samples were left untreated and kept for future use.

(b) Preparation of surfactant composition S04

Wherein r is₁+r₂＝0，s₁+s₂＝5，r₃+r₄＝15。

325 g (1 mol) of icosanediamine, 2.3 g of potassium hydroxide and 8.4 g of anhydrous potassium carbonate are added into a 2L pressure reactor provided with a stirring device, a vacuum system is started when the temperature is heated to 80-90 ℃, dehydration is carried out for 1 hour under high vacuum, then nitrogen is used for replacing for 3-4 times, the reaction temperature of the system is adjusted to 130 ℃, 295.8 g (5.1 mol) of propylene oxide is slowly introduced, the pressure is controlled to be less than or equal to 0.60MPa, and 664.4 g (15.1 mol) of ethylene oxide is slowly introduced when the reaction of the propylene oxide is finished. After the reaction is finished, the temperature is reduced to 90 ℃, low-boiling-point substances are removed in vacuum, neutralization and dehydration are carried out after cooling, 1201.1 g of the icosapolyoxypropylene (5) polyoxyethylene (15) ether are obtained, and the yield is 94.2%.

Icosanediamine polyoxypropylene (5) polyoxyethylene (15) ether 637.5 g (0.5 mol) was mixed with 200 g (5 mol) sodium hydroxide, 589.5 g (3 mol) sodium 3-chloro-2-hydroxypropanesulfonate and 800 ml toluene/benzene (v/v ═ 2) in a 5000 ml four-neck flask equipped with a mechanical stirrer, thermometer and reflux condenser, and heated to 85 ℃ for 8 hours. Cooling, taking 50 g of uniform reaction liquid, acidifying with 20 wt% hydrochloric acid, separating water and inorganic salt, evaporating to remove the solvent, adopting a Mettler company T90 automatic potentiometric titrator, taking a Heimemin cation solution as a titrant, and measuring the sulfonation degree to be 168.7% through potentiometric dropping. The remaining untreated reaction solution was distilled off the solvent, 600 g of water, an aqueous isopropanol solution containing 806.0 g (2.0 mol) of the inner salt of (N-carboxymethyl-N, N-dimethyl) -4-hexadecylphenylammonium were added, and stirring was continued at 40 ℃ for 4 hours to obtain the desired surfactant composition S04.

Phase and static adsorption experiments were carried out as in [ example 12 ] and the results are shown in tables 2 and 3.

(c) Performance test of oil-displacing agent

The same as [ example 14 ] except that S04 was used in place of S03 and 10# simulated water to prepare an aqueous solution of an oil-displacing agent at a temperature of 85 ℃ and a viscosity of dehydrated crude oil of 59.5mPa.s, the results are shown in Table 7.

[ example 16 ]

(a) Preparation of (N- (2-hydroxy-3-propanesulfonic acid) -N-methyl-N-hexadecyl) -4-methylphenyl ammonium inner salt

345.0 g (1 mol) of N-hexadecyl-N-methyl-4-methylaniline, 357.3 g (1.8 mol) of sodium 3-chloro-2-hydroxypropanesulfonate and 800 g of a 25 wt% aqueous ethanol solution were mixed in a 2000-ml four-necked flask equipped with a mechanical stirrer, a thermometer and a reflux condenser, and the mixture was heated to reflux reaction for 12 hours to stop the reaction. A small amount of the reaction solution was subjected to HPLC analysis, the ratio of (N- (2-hydroxy-3-propanesulfonic acid) -N-methyl-N-hexadecyl) -4-methylphenylammonium inner salt to N-hexadecyl-N-methyl-4-methylaniline was 87.5:12.5, and the remaining sample was left untreated and was used for future use.

(b) Preparation of surfactant composition S05

R₅Is C₁₄H₂₉；Z₁＝Z₂＝CH₂COONa r₁+r₂＝3，s₁+s₂＝12，r₃+r₄＝4。

Adding 213 g (1 mol) of tetradecylamine and 8.2 g of potassium hydroxide into a 5L pressure reactor provided with a stirring device, heating to 80-90 ℃, starting a vacuum system, dehydrating for 1 hour under high vacuum, then replacing for 3-4 times with nitrogen, adjusting the reaction temperature of the system to 110 ℃, slowly introducing 132.9 g (3.02 mol) of ethylene oxide, controlling the pressure to be less than or equal to 0.50MPa, after the reaction of the ethylene oxide is finished, slowly introducing 701.8 g (12.1 mol) of propylene oxide at 150 ℃, controlling the pressure to be less than or equal to 0.60MPa, and after the reaction of the propylene oxide is finished, adjusting the temperature to 130 ℃, and slowly introducing 178.2 g (4.05 mol) of ethylene oxide. After the reaction is finished, the temperature is reduced to 90 ℃, low-boiling-point substances are removed in vacuum, neutralization and dehydration are carried out after cooling, 1158.6 g of decatetramine polyoxyethylene (3), polyoxypropylene (12) and polyoxyethylene (4) ether are obtained, and the yield is 95.2%.

Introducing nitrogen into a 5000 ml reaction bottle provided with a mechanical stirring pipe, a thermometer and a reflux condenser pipe to remove water vapor, adding 608.5 g (0.5 mol) of tetradecylamine polyoxyethylene (3), polyoxypropylene (12) polyoxyethylene (4) ether and 108.0 g (2.0 mol) of sodium methoxide under the protection of nitrogen, slowly dripping 162.8 g (1.5 mol) of methyl chloroacetate, controlling the reaction temperature to be 65 ℃ for reacting for 8 hours, cooling, adding 1000 g of water and 50 g of methanol, and continuously heating until the reflux reaction is carried out for 5 hours. Cooling, taking 50 g of uniform reaction liquid, acidifying with 20 wt% hydrochloric acid, evaporating methanol, adding 100 g of benzene, mixing, removing a water layer, washing with saturated saline solution for 3 times, decompressing, evaporating benzene, and measuring the carboxylation degree to be 180.2% by adopting a Mettler company T90 automatic potentiometric titrator and taking a Halmin cation solution as a titrant. The remaining untreated reaction solution was added with 1000 g of water, 10.5 g (0.1 mol) of diethanolamine, and an aqueous ethanol solution containing 36.2 g (0.05 mol) of an inner salt of (N- (2-hydroxy-3-propanesulfonic acid) -N-methyl-N-hexadecyl) -4-methylphenylammonium, and stirred at 45 ℃ for 3 hours to obtain the desired surfactant composition S05. Phase and static adsorption experiments were carried out as in [ example 12 ] and the results are shown in tables 2 and 3.

(c) Performance test of oil-displacing agent

Except that S05 is used for replacing S01, high molecular weight anionic polyacrylamide P4 (viscosity average molecular weight is 2300 ten thousand) is used for replacing modified polyacrylamide polymer (P1, the molar ratio of the copolymer AM/AMPS is 1/0.05, and the viscosity average molecular weight is 2500 ten thousand), 11# simulated water is used for preparing an oil displacement agent aqueous solution, the temperature is 55 ℃, the viscosity of crude oil is 125.9mPa.s, and the result is shown in Table 6.

[ example 17 ]

(a) Preparation of (N-carboxymethyl-N, N-dimethyl) phenyl ammonium inner salt

121.0 g (1 mol) of N, N-dimethylaniline, 139.8 g (1.2 mol) of sodium chloroacetate and 500g of a 5 wt% aqueous isopropanol solution were mixed in a 2000-ml four-necked flask equipped with a mechanical stirrer, a thermometer and a reflux condenser, and the mixture was heated to reflux for 8 hours to stop the reaction. And (3) taking a small amount of reaction liquid for HPLC analysis, wherein the ratio of the (N-carboxymethyl-N, N-dimethyl) phenyl ammonium inner salt to the N, N-dimethylaniline is 95.1:4.9, and the rest samples are not processed for later use.

(b) Preparation of surfactant composition S06

R₅Is CH₃(CH₂)₇CH＝CH(CH₂)₈；Z₁＝Z₂＝CH₂COONa r₁+r₂＝3，s₁+s₂＝12，r₃+r₄＝4。

Adding 267.0 g (1 mol) of 9-ene-octadecylamine and 9.5 g of potassium hydroxide into a 5L pressure reactor provided with a stirring device, heating to 80-90 ℃, starting a vacuum system, dehydrating for 1 hour under high vacuum, then replacing for 3-4 times with nitrogen, adjusting the reaction temperature of the system to 110 ℃, slowly introducing 132.9 g (3.02 mol) of ethylene oxide, controlling the pressure to be less than or equal to 0.50MPa, after the reaction of the ethylene oxide is finished, slowly introducing 701.8 g (12.1 mol) of propylene oxide at 150 ℃, controlling the pressure to be less than or equal to 0.60MPa, and after the reaction of the propylene oxide is finished, adjusting the temperature to 130 ℃, and slowly introducing 178.2 g (4.05 mol) of ethylene oxide. After the reaction is finished, the temperature is reduced to 90 ℃, low-boiling-point substances are removed in vacuum, and neutralization and dehydration are carried out after cooling, so that 1230.3 g of 9-ene octadecylamine polyoxyethylene (3), polyoxypropylene (12) polyoxyethylene (4) ether are obtained, and the yield is 96.8%.

Introducing nitrogen into a 5000 ml reaction bottle provided with a mechanical stirring device, a thermometer and a reflux condenser tube to remove moisture, adding 635.5 g (0.5 mol) of 9-ene-octadecylamine polyoxyethylene (3) polyoxypropylene (12) polyoxyethylene (4) ether and 108.0 g (2.0 mol) of sodium methoxide under the protection of nitrogen, slowly dripping 162.8 g (1.5 mol) of methyl chloroacetate, controlling the reaction temperature to be 65 ℃ for reacting for 8 hours, cooling, adding 1000 g of water and 50 g of methanol, and continuously heating until reflux reaction is carried out for 5 hours. Cooling, taking 50 g of uniform reaction liquid, acidifying with 20 wt% hydrochloric acid, evaporating methanol, adding 100 g of benzene, mixing, removing a water layer, washing with saturated saline solution for 3 times, decompressing, evaporating benzene, and measuring the carboxylation degree to be 185.6% by adopting a Mettler company T90 automatic potentiometric titrator and using a Helminum cation solution as a titrant. The remaining untreated reaction solution was added 1200 g of water, an aqueous isopropanol solution containing 3.6 g (0.02 mol) of the inner salt of (N-carboxymethyl-N, N-dimethyl) phenylammonium, and mixed well to obtain the desired surfactant composition S06. Phase and static adsorption experiments were carried out as in [ example 12 ] and the results are shown in tables 2 and 3.

(c) Performance test of oil-displacing agent

The same as [ example 14 ] except that an aqueous displacement agent solution was prepared by replacing S03 with S06, and the results are shown in table 7.

[ example 18 ]

(a) Preparation of (N-carboxymethyl-N, N-diethyl) phenyl ammonium inner salt

144.0 g (1 mol) of N, N-diethylaniline, 151.5 g (1.3 mol) of sodium chloroacetate, and 500g of a 15 wt% aqueous solution of isopropanol were mixed in a 2000 ml four-necked flask equipped with a mechanical stirrer, a thermometer, and a reflux condenser, and the mixture was heated to reflux reaction for 8 hours to stop the reaction. And (3) taking a small amount of reaction liquid for HPLC analysis, wherein the ratio of the (N-carboxymethyl-N, N-diethyl) phenyl ammonium inner salt to the N, N-diethylaniline is 92.5:7.5, and the rest samples are not processed for later use.

(b) Preparation of surfactant composition S07

R₅Is CH₃(CH₂)₇CH＝CH(CH₂)₈；Z₁＝Z₂＝CH₂COONa r₁+r₂＝3，s₁+s₂＝12，r₃+r₄＝4。

Adding 267.0 g (1 mol) of 9-ene-octadecylamine and 9.5 g of potassium hydroxide into a 5L pressure reactor provided with a stirring device, heating to 80-90 ℃, starting a vacuum system, dehydrating for 1 hour under high vacuum, then replacing for 3-4 times with nitrogen, adjusting the reaction temperature of the system to 110 ℃, slowly introducing 132.9 g (3.02 mol) of ethylene oxide, controlling the pressure to be less than or equal to 0.50MPa, after the reaction of the ethylene oxide is finished, slowly introducing 701.8 g (12.1 mol) of propylene oxide at 150 ℃, controlling the pressure to be less than or equal to 0.60MPa, and after the reaction of the propylene oxide is finished, adjusting the temperature to 130 ℃, and slowly introducing 178.2 g (4.05 mol) of ethylene oxide. After the reaction is finished, the temperature is reduced to 90 ℃, low-boiling-point substances are removed in vacuum, and neutralization and dehydration are carried out after cooling, so that 1230.3 g of 9-ene octadecylamine polyoxyethylene (3), polyoxypropylene (12) polyoxyethylene (4) ether are obtained, and the yield is 96.8%.

Introducing nitrogen into a 5000 ml reaction bottle provided with a mechanical stirring device, a thermometer and a reflux condenser tube to remove moisture, adding 635.5 g (0.5 mol) of 9-ene-octadecylamine polyoxyethylene (3) polyoxypropylene (12) polyoxyethylene (4) ether and 108.0 g (2.0 mol) of sodium methoxide under the protection of nitrogen, slowly dripping 162.8 g (1.5 mol) of methyl chloroacetate, controlling the reaction temperature to be 65 ℃ for reacting for 8 hours, cooling, adding 1000 g of water and 50 g of methanol, and continuously heating until reflux reaction is carried out for 5 hours. Cooling, taking 50 g of uniform reaction liquid, acidifying with 20 wt% hydrochloric acid, evaporating methanol, adding 100 g of benzene, mixing, removing a water layer, washing with saturated saline solution for 3 times, decompressing, evaporating benzene, and measuring the carboxylation degree to be 185.6% by adopting a Mettler company T90 automatic potentiometric titrator and using a Helminum cation solution as a titrant. The remaining untreated reaction solution was added 1200 g of water, an aqueous isopropanol solution containing 10.3 g (0.05 mole) of the inner salt of (N-carboxymethyl-N, N-diethyl) phenylammonium, and mixed well to give the desired surfactant composition S07.

Phase and static adsorption experiments were carried out as in [ example 12 ] and the results are shown in tables 2 and 3.

(c) Performance test of oil-displacing agent

The same as [ example 14 ] except that an aqueous displacement agent solution was prepared by replacing S03 with S07, and the results are shown in table 7.

[ example 19 ]

(a) Preparation of (N-carboxymethyl-N-methyl-N-ethyl) phenylammonium inner salt

130.0 g (1 mol) of N-methyl-N-ethylaniline, 151.5 g (1.3 mol) of sodium chloroacetate, and 500g of a 15 wt% aqueous solution of isopropanol were mixed in a 2000-ml four-necked flask equipped with a mechanical stirrer, a thermometer, and a reflux condenser, and the mixture was heated to reflux reaction for 6.5 hours, and the reaction was stopped. And (3) taking a small amount of reaction liquid for HPLC analysis, wherein the ratio of (N-methyl-N-ethyl) phenyl ammonium inner salt to N-methyl-N-ethylaniline is 93.7:6.3, and the rest samples are not processed for later use.

(b) Surfactant composition S08 was prepared

R₅Is CH₃(CH₂)₇CH＝CH(CH₂)₈；Z₁＝Z₂＝CH₂COONa r₁+r₂＝3，s₁+s₂＝12，r₃+r₄＝4。

Adding 267.0 g (1 mol) of 9-ene-octadecylamine and 9.5 g of potassium hydroxide into a 5L pressure reactor provided with a stirring device, heating to 80-90 ℃, starting a vacuum system, dehydrating for 1 hour under high vacuum, then replacing for 3-4 times with nitrogen, adjusting the reaction temperature of the system to 110 ℃, slowly introducing 132.9 g (3.02 mol) of ethylene oxide, controlling the pressure to be less than or equal to 0.50MPa, after the reaction of the ethylene oxide is finished, slowly introducing 701.8 g (12.1 mol) of propylene oxide at 150 ℃, controlling the pressure to be less than or equal to 0.60MPa, and after the reaction of the propylene oxide is finished, adjusting the temperature to 130 ℃, and slowly introducing 178.2 g (4.05 mol) of ethylene oxide. After the reaction is finished, the temperature is reduced to 90 ℃, low-boiling-point substances are removed in vacuum, and neutralization and dehydration are carried out after cooling, so that 1230.3 g of 9-ene octadecylamine polyoxyethylene (3), polyoxypropylene (12) polyoxyethylene (4) ether are obtained, and the yield is 96.8%.

Introducing nitrogen into a 5000 ml reaction bottle provided with a mechanical stirring device, a thermometer and a reflux condenser tube to remove moisture, adding 635.5 g (0.5 mol) of 9-ene-octadecylamine polyoxyethylene (3) polyoxypropylene (12) polyoxyethylene (4) ether and 108.0 g (2.0 mol) of sodium methoxide under the protection of nitrogen, slowly dripping 162.8 g (1.5 mol) of methyl chloroacetate, controlling the reaction temperature to be 65 ℃ for reacting for 8 hours, cooling, adding 1000 g of water and 50 g of methanol, and continuously heating until reflux reaction is carried out for 5 hours. Cooling, taking 50 g of uniform reaction liquid, acidifying with 20 wt% hydrochloric acid, evaporating methanol, adding 100 g of benzene, mixing, removing a water layer, washing with saturated saline solution for 3 times, decompressing, evaporating benzene, and measuring the carboxylation degree to be 185.6% by adopting a Mettler company T90 automatic potentiometric titrator and using a Helminum cation solution as a titrant. The remaining untreated reaction solution was added with 1200 g of water, an aqueous isopropanol solution containing 18.8 g (0.1 mol) of the inner salt of (N-methyl-N-ethyl) phenylammonium, and mixed well to obtain the desired surfactant composition S08. Phase and static adsorption experiments were carried out as in [ example 12 ] and the results are shown in tables 2 and 3.

(c) Performance test of oil-displacing agent

The same as [ example 14 ] except that an aqueous displacement agent solution was prepared by replacing S03 with S08, and the results are shown in table 7.

[ example 20 ]

The same as in example 1, except that the alcohol solvent was distilled off under reduced pressure at the end of the reaction in the step (a), to obtain the desired surfactant composition S09.

Phase and static adsorption experiments were carried out as in [ example 12 ] and the results are shown in tables 2 and 3.

S09 is used for replacing S01 to prepare an oil displacement agent aqueous solution, and the results of adsorption and oil displacement experiments are shown in Table 6.

[ example 21 ]

(a) Preparation of (N-carboxymethyl-N-octadecyl-N-methyl) phenylammonium inner salt

359.0 g (1 mol) of N-octadecyl-N-methylaniline, 174.8 g (1.5 mol) of sodium chloroacetate, and 750 g of a 50 wt% aqueous ethanol solution were mixed in a 2000 ml four-necked flask equipped with a mechanical stirrer, a thermometer, and a reflux condenser, and the mixture was heated to reflux for 8 hours to stop the reaction. A small amount of the reaction solution was taken for HPLC analysis, and the ratio of (N-carboxymethyl-N-octadecyl-N-methyl) phenylammonium inner salt to N-octadecyl-N-methylaniline was 96.7:3.3, as shown in FIG. 1. Dissolving ethyl acetate for desalting for multiple times, removing organic solvent to obtain zwitterionic surfactant, and performing infrared spectrum analysis (scan range 4000-400 cm) by liquid membrane method with Nicolet-5700 infrared spectrometer^-1) The infrared spectrum is shown in figure 2. The remaining samples were left untreated and were ready for use.

(b) Preparation of surfactant composition S10

Z₁＝Z₂＝H；r₁+r₂＝4，s₁+s₂＝15，r₃+r₄＝3。

Adding 261 g (1 mol) of dodecylaniline, 5.9 g of sodium hydroxide and 11.9 g of anhydrous potassium carbonate into a 5L pressure reactor provided with a stirring device, heating to 80-90 ℃, starting a vacuum system, dehydrating for 1 hour under high vacuum, then replacing for 3-4 times with nitrogen, adjusting the reaction temperature of the system to 110 ℃, slowly introducing 178.2 g (4.05 mol) of ethylene oxide, controlling the pressure to be less than or equal to 0.50MPa, after the reaction of the ethylene oxide is finished, slowly introducing 881.6 g (15.2 mol) of propylene oxide at 150 ℃, controlling the pressure to be less than or equal to 0.60MPa, and after the reaction of the propylene oxide is finished, adjusting the temperature to 140 ℃, and slowly introducing 134.2 g (3.05 mol) of ethylene oxide. After the reaction is finished, the temperature is reduced to 90 ℃, low-boiling-point substances are removed in vacuum, and after cooling, neutralization and dehydration are carried out, 1394.4 g of dodecylaniline polyoxyethylene (4), polyoxypropylene (15), polyoxyethylene (3) ether are obtained, and the yield is 96.9%.

Dodecylaniline polyoxyethylene (4) polyoxypropylene (15) polyoxyethylene (3) ether 5.8 g (0.004 mol), 200 g water, 126.0 g (1.2 mol) diethanolamine, 83.4. g (0.2 mol) aqueous ethanol of (N-carboxymethyl-N-octadecyl-N-methyl) phenyl ammonium inner salt, and mixing them uniformly to obtain the desired surfactant composition S10.

S11。

Phase and static adsorption experiments were carried out as in [ example 12 ] and the results are shown in tables 2 and 3.

S10 is used for replacing S01 to prepare an oil displacement agent aqueous solution, and the results of adsorption and oil displacement experiments are shown in Table 6.

[ COMPARATIVE EXAMPLE 2 ]

Octadecyl benzyl methyl betaine

Octadecyl dimethyl betaine

The same as in example 12 except that (N-carboxymethyl-N-octadecyl-N-methyl) phenylammonium inner salt was replaced with commercially available octadecyl benzyl methyl betaine or octadecyl dimethyl betaine, the rest was the same, to give surfactant compositions S11 and S12. The results of preparing the oil-displacing agent aqueous solution by replacing S01 with S11 and S12 are shown in Table 8.

[ COMPARATIVE EXAMPLE 3 ]

The same as [ example 12 ] except that the hydrophobically associative polymer P1 was replaced with a high molecular weight anionic polyacrylamide P4 (having a viscosity average molecular weight of 2300 ten thousand), and the results were as shown in table 8.

TABLE 6

TABLE 7

TABLE 8

Claims (10)

1. A surfactant composition comprising the following components:

(1) a zwitterionic compound;

(2) a polyetheramine surfactant;

wherein the molar ratio of the zwitterionic compound to the polyether amine surfactant is 1 (0.01-50); the molecular general formula of the zwitterionic compound is shown as the formula (I):

in the formula (I), R₁And R₄Is hydrogen, C₂～C₃₂Alkyl or substituted alkyl of (CH R')_cOH、(CH R')_dCH₃One of phenyl, substituted phenyl or benzyl; r₂Is C₁～C₅Alkylene or substituted alkylene, X^-Is carboxylate, sulfonate, phosphate or sulfate radical; r₃Is hydrogen, C₂～C₃₂Alkyl or substituted alkyl (CHR')_eOne of OH, halogen, amino, carboxylic acid group or sulfonic group; r 'and R' are independently selected from H, CH₃Or C₂H₅One of (1); c is any integer of 1-4; d is any integer of 0-5; e is any integer of 0-4;

the molecular general formula of the polyether amine surfactant is shown as a formula (II):

in the formula (II), R₅Is C₈～C₃₀Or linear or branched, saturated or unsaturated alkyl or from C₄～C₂₀Saturated and unsaturated hydrocarbon radicals, straight-chain or branched, or cumyl (C)₆H₅C(CH₃)₂) Substituted benzene or naphthalene rings, or R₅Is abietylamine radical; r1, r2, r3 or r4 are independently selected from 0-50, but r1 and r2, and r3 and r4 cannot be 0 at the same time; s1 and s2 are independently selected from 0-100, but s1 and s2 cannot be 0 at the same time; y is R₆Z; y 'is R'₆Z′；R₆And R'₆Is independently selected from C₁～C₅At least one of alkylene or hydroxy-substituted alkylene of (a); z and Z' are independently selected from COOM, SO₃And one of N, M, N is selected from cation or cation group.

2. The surfactant composition of claim 1, wherein said M, N is selected from the group consisting of hydrogen ions, alkali metal cations, and mixtures thereof₇(R₈)(R₉)(R₁₀) At least one of the groups shown, wherein R₇、R₈、R₉、R₁₀Independently selected from H, (CHR)⁰)_fOH or (CHR)⁰)_gCH₃One of (1), R⁰Is H, CH₃Or C₂H₅Wherein f is any integer from 1 to 4, and g is any integer from 0 to 5.

3. The surfactant composition according to claim 1 or 2, characterized in that R is₁And R₄Is hydrogen, C₈～C₂₄One of alkyl or substituted alkyl, methyl, ethyl, hydroxyethyl, hydroxypropyl, phenyl and benzyl; r₂X^-Is C₁～C₃Alkylene or substituted alkylene carboxylic acidsAcid radical, C₁～C₃One of alkylene or substituted alkylene sulfonate; r₃Is hydrogen, C₈～C₂₄One of alkyl or substituted alkyl, hydrogen, methyl, ethyl, phenyl, hydroxyl, amino, carboxylic acid group or sulfonic acid group; r ', R', R⁰Independently selected from H or CH₃(ii) a c is 1-2, d is 0-1, e is 0-1, f is 1-2, g is 0-1, and j is 0 or 1; the R is₅Is C₁₂～C₂₄Or with a hydrocarbon or substituted hydrocarbon radical of₄～C₂₀Saturated and unsaturated hydrocarbon radicals, straight-chain or branched, or cumyl (C)₆H₅C(CH₃)₂) A substituted benzene or naphthalene ring; r₆Is C₁～C₃One of alkylene groups of (a); the r1+ r2 is 1-10, r3+ r4 is 1-10, and s1+ s2 is 1-40.

4. The surfactant composition according to claim 1, characterized in that the composition further comprises:

(3) a small molecule alcohol;

(4) a small molecule amine;

(5) salt;

(6) an inorganic base;

wherein the molar ratio of the zwitterionic compound, the polyether amine surfactant, the small molecular alcohol, the small molecular amine, the salt and the inorganic base is 1 (0.01-50): (0-20): 0-10); the small molecule alcohol is preferably selected from C₁～C₈The fatty alcohol of (a); the small molecule amine is preferably selected from C₁～C₈At least one of a primary amine, a secondary amine, or a tertiary amine; the salt is preferably selected from at least one of a metal halide, a hydroxy-substituted carboxylate; the inorganic base is preferably at least one selected from an alkali metal hydroxide, an alkali metal carbonate or an alkali metal hydrogencarbonate; further preferably: the preferred molar ratio of the zwitterionic compound, the polyether amine surfactant, the small molecular alcohol, the small molecular amine, the salt and the inorganic base is 1 (0.02-30): 0-15): 0-5.

5. A method of preparing a surfactant composition comprising the steps of:

(a) preparation of zwitterionic compound:

will be provided with

With ionizing agents X₀R₂Uniformly mixing the X in water or alcohol water for quaternization reaction to obtain an aqueous solution or an alcohol aqueous solution of the zwitterionic compound shown in the formula (I); wherein the alcohol accounts for 0-100 wt% of the alcohol aqueous solution in percentage by mass, and the alcohol is selected from C₁～C₅Fatty alcohol of (2), X₀Selected from chlorine, bromine or iodine;

(b) preparation of surfactant composition:

in the presence of an alkaline catalyst, R₅NH₂Reacting with required amount of ethylene oxide, propylene oxide and ethylene oxide in sequence to obtain a polyether compound; mixing a desired amount of a polyether compound with the aqueous or aqueous alcoholic solution of the zwitterionic compound obtained in step (a) to obtain said surfactant composition;

or obtaining the surfactant composition by a second reaction:

② the polyether compound obtained in the step I and an ionizing agent Y₀R₆Z or Y₀R'₆Mixing Z' and alkali metal hydroxide or alkali metal alkoxide according to a molar ratio of 1 (0.1-20) to 0.1-20, reacting at a reaction temperature of 50-120 ℃ for 3-15 hours under stirring, adding the zwitterionic compound aqueous solution or alcohol aqueous solution obtained in the step (a) according to a required molar ratio, heating to 40-100 ℃, and stirring for 1-5 hours to obtain the surfactant composition; wherein, Y₀Selected from chlorine, bromine or iodine;

or: ② the polyether compound obtained in the step I and an ionizing agent Y₀R₆COOR₀Or Y₀R'₆COOR₀And alkali metal hydroxide or alkali metal alkoxide in a molar ratio of 1 (0.1-20) to 0.1-20, reacting at 50-120 ℃ for 3-15 hours while stirring, further adding water to perform saponification, refluxing for 1-10 hours, and then adding water to the mixtureAdding the zwitterionic compound aqueous solution or alcohol aqueous solution obtained in the step (a) according to a required molar ratio, heating to 40-100 ℃, and stirring for 1-5 hours to obtain a required surfactant composition; wherein R is₀Is selected from C₁～C₈Alkyl group of (1).

6. The process for preparing a surfactant composition according to claim 5, wherein the ionizing agent X is₀R₂X is at least one of alkali metal salt of 3-chloro-2-hydroxypropanesulfonic acid, alkali metal salt of 2-chloroethanesulfonic acid, alkali metal salt of 1, 3-propanesultone, chloroacetic acid and alkali metal salt of chloroacetic acid sulfonating agent, and the alcohol is selected from C₁～C₄The fatty alcohol of (a); the above-mentioned

And X₀R₂The molar ratio of X is 1: 1-3; in the first step, the reaction temperature is 120-160 ℃, the pressure is 0.3-0.6 MPa gauge pressure, and the alkaline catalyst is at least one of potassium hydroxide or anhydrous potassium carbonate; in the second step, the alkali metal hydroxide is at least one of potassium hydroxide or sodium hydroxide, the molar ratio of the polyether compound to the ionizing agent and the alkali metal hydroxide or the alkali metal alkoxide is 1 (2-10) to (2-10), and X is₀And Y₀Is one of chlorine or bromine, R₀Is C₁～C₄Alkyl group of (1).

7. Use of the surfactant composition of any of claims 1 to 4 in oil field applications.

8. An oil displacement agent comprises the following components in parts by weight:

(1)1 part of the surfactant composition according to any one of claims 1 to 4 or the surfactant composition prepared by the preparation method according to any one of claims 5 to 6;

(2)0 to 20 parts of a polymer and more than 0 part of a polymer;

(3) 0-30 parts of alkali;

wherein the polymer is preferably at least one of anionic polyacrylamide, temperature-resistant and salt-resistant modified polyacrylamide, hydrophobically associating polyacrylamide or polymer microspheres; further preferably, the temperature-resistant and salt-resistant modified polyacrylamide molecular chain preferably comprises an acrylamide structural unit and a 2-acrylamido-2-methylpropanesulfonic acid structural unit, wherein the molar ratio of the acrylamide structural unit to the 2-acrylamido-2-methylpropanesulfonic acid structural unit is preferably (0.1-40) to 1, and the viscosity-average molecular weight is preferably 800-2500 ten thousand; the molecular chain of the hydrophobic association polymer preferably comprises an acrylamide structural unit, a temperature-resistant and salt-resistant monomer structural unit and a hydrophobic monomer structural unit, wherein the molar ratio of the acrylamide structural unit to the temperature-resistant and salt-resistant monomer structural unit to the hydrophobic monomer structural unit is preferably 1: (0.1-40): (0.001 to 0.05) and preferably has a viscosity average molecular weight of 500 to 2500 ten thousand; in the oil displacement agent, the mass ratio of the surfactant composition to the polymer to the alkali is preferably 1 to (0.1-2): (0-5).

9. A method for preparing the oil-displacing agent of claim 8, comprising the steps of:

(a) preparation of zwitterionic compound:

will be provided with

With ionizing agents X₀R₂Uniformly mixing the X in water or alcohol water for quaternization reaction to obtain an aqueous solution or an alcohol aqueous solution of the zwitterionic compound shown in the formula (I); wherein the alcohol accounts for 0-100 wt% of the alcohol aqueous solution in percentage by mass, and the alcohol is selected from C₁～C₅Fatty alcohol of (2), X₀Selected from chlorine, bromine or iodine;

(b) preparation of surfactant composition:

in the presence of an alkaline catalyst, R₅NH₂Reacting with required amount of ethylene oxide, propylene oxide and ethylene oxide in sequence to obtain a polyether compound; mixing a required amount of polyether compound with the aqueous solution or the aqueous alcohol solution of the zwitterionic compound obtained in the step (a) to obtain the surfactant groupA compound;

or obtaining the surfactant composition by a second reaction:

② the polyether compound obtained in the step I and an ionizing agent Y₀R₆Z or Y₀R'₆Mixing Z' and alkali metal hydroxide or alkali metal alkoxide according to a molar ratio of 1 (0.1-20) to 0.1-20, reacting at a reaction temperature of 50-120 ℃ for 3-15 hours under stirring, adding the zwitterionic compound aqueous solution or alcohol aqueous solution obtained in the step (a) according to a required molar ratio, heating to 40-100 ℃, and stirring for 1-5 hours to obtain the surfactant composition; wherein, Y₀Selected from chlorine, bromine or iodine;

or: ② the polyether compound obtained in the step I and an ionizing agent Y₀R₆COOR₀Or Y₀R'₆COOR₀And alkali metal hydroxide or alkali metal alkoxide are mixed according to the molar ratio of 1 (0.1-20) to 0.1-20, the mixture is stirred and reacted at the reaction temperature of 50-120 ℃ for 3-15 hours, water is continuously added for saponification reaction, after refluxing for 1-10 hours, the zwitterionic compound aqueous solution or alcohol aqueous solution obtained in the step (a) is added according to the required molar ratio, the temperature is raised to 40-100 ℃, and the mixture is stirred for 1-5 hours, so that the required surfactant composition is obtained; wherein R is₀Is selected from C₁～C₈Alkyl group of (1).

(c) Uniformly mixing the required amount of the surfactant composition obtained in the step (b) with a polymer and alkali according to the mass parts to obtain the oil-displacing agent;

wherein, the preferred scheme is as follows: the ionizing agent X₀R₂X is preferably at least one of an alkali metal salt of 3-chloro-2-hydroxypropanesulfonic acid, an alkali metal salt of 2-chloroethanesulfonic acid, 1, 3-propanesultone, chloroacetic acid, and an alkali metal salt of chloroacetic acid sulfonating agent, and the alcohol is preferably selected from C₁～C₄The fatty alcohol of (a); the above-mentioned

And X₀R₂The preferable molar ratio of X is 1: 1-3; the method comprises the following steps: the reaction temperature is preferably120-160 ℃, the pressure is preferably 0.3-0.6 MPa gauge pressure, and the alkaline catalyst is preferably at least one of potassium hydroxide or anhydrous potassium carbonate; the second step is as follows: the alkali metal hydroxide is preferably at least one of potassium hydroxide or sodium hydroxide, and the molar ratio of the polyether compound to the ionizing agent and the alkali metal hydroxide or the alkali metal alkoxide is preferably 1 (2-10): 2-10), and X₀And Y₀Preferably one of chlorine or bromine, R₀Preferably C₁～C₄Alkyl group of (1).

10. The application of the oil displacement agent comprises the following steps:

(1) mixing the oil-displacing agent of claim 8 with water to obtain an oil-displacing system;

(2) and contacting the oil displacement system with an oil-bearing stratum under the conditions that the oil displacement temperature is 25-150 ℃ and the total salinity is more than 500 mg/L of simulated formation water, and displacing the crude oil in the oil-bearing stratum.

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