阅读说明：本技术 油水乳液乳化剂组合物 (Oil-water emulsion emulsifier composition ) 是由 黄建滨 马骋 刘卡尔顿 程新皓 赵海娜 朱志扬 于 2019-06-10 设计创作，主要内容包括：本发明提供了一种油水乳液乳化剂组合物,所述组合物包含至少一种式(1)所示的有机酸和至少一种式(2)所示的多胺,并且所述有机酸与所述多胺的总摩尔比为1:100-100:1。所述组合物可用于使油水混合物快速乳化形成稳定的油包水型乳液,所述油包水型乳液可具有低至超低的油水体积比。R<Sub>1</Sub>-A<Sub>1</Sub>式(1)NH<Sub>2</Sub>-[(CH<Sub>2</Sub>)<Sub>m</Sub>NH]<Sub>n</Sub>-H式(2)。(The invention provides an oil-water emulsion emulsifier composition, which comprises at least one organic acid shown as a formula (1) and at least one polyamine shown as a formula (2), wherein the total molar ratio of the organic acid to the polyamine is 1:100-100: 1. The composition is useful for rapidly emulsifying oil and water mixtures to form stable water-in-oil emulsions, which can have low to ultra-low oil to water volume ratios. R 1 ‑A 1 Formula (1) NH 2 ‑[(CH 2 ) m NH] n -H formula (2).)

1. An oil and water emulsion emulsifier composition comprising at least one organic acid of formula (1) and at least one polyamine of formula (2):

R₁-A₁

Formula (1)

NH₂-[(CH₂)_mNH]_n-H

Formula (2)

Wherein R is₁is a substituted or unsubstituted straight chain C₅-C₂₀A saturated or unsaturated hydrocarbon group;

A₁Is carboxyl, sulfonic group, sulfuric group or phosphoric group;

Each m is independently an integer from 1 to 5;

n is an integer of 1 to 5; and is

Wherein the total molar ratio of the organic acid to the polyamine is 1:100 to 100: 1.

2. The composition of claim 1, wherein R₁Is straight chain C₁₂-C₁₈Alkyl, alkenyl or dienyl, and/or A₁Is a carboxyl group; preferably, the organic acid is selected from the group consisting of the following carboxylic acids: lauric acid, myristic acid, palmitic acid, oleic acid, and linoleic acid.

3. The composition of claim 1 or 2, wherein each m is independently an integer from 2 to 3, n is an integer from 2 to 4; preferably, the polyamine is one or more of ethylenediamine, diethylenetriamine, triethylenetetramine and tetraethylenepentamine; further preferably, the polyamine is diethylenetriamine or tetraethylenepentamine.

4. A composition according to any one of claims 1-3, wherein the total molar ratio of the organic acid to the polyamine is at least 1:20, preferably at least 1:10, more preferably at least 1:5, further preferably at least 1: 3; and/or

the total molar ratio of the organic acid to the polyamine is at most 20:1, preferably at most 10:1, more preferably at most 5:1, further preferably at most 3: 1.

5. The composition according to any one of claims 1 to 4, wherein the composition further comprises at least one of the following additives: nonionic surfactant, pH regulator, inorganic salt and water phase solvent.

6. Use of a composition according to any one of claims 1 to 5 for the preparation of a water-in-oil emulsion comprising an oil phase and an aqueous phase, the volume ratio of the aqueous phase to the oil phase being from 1:1 to 100: 1.

7. A process for preparing a water-in-oil emulsion, the process comprising the steps of:

(a-1) preparing the composition of any one of claims 1 to 5 in water at normal temperature into an aqueous solution (i) with a total mass concentration of 40 to 60%, and then further diluting the aqueous solution (i) into an aqueous solution (ii) with a total mass concentration of 2 to 5%; and

(A-2) adding the aqueous solution (ii) obtained in the step (A-1) into an oil-water mixture until the total mass concentration of the composition in the oil-water mixture is 0.2% -0.5%, shaking and standing,

The oil-water mixture comprises an oil phase and a water phase, wherein the oil phase is one or more of crude oil, white oil and kerosene, the water phase is deionized water and/or oilfield formation water injection, and the volume ratio of the water phase to the oil phase is 1:1-100: 1.

8. A method of evaluating the emulsifying ability of a composition according to any one of claims 1 to 5, comprising the steps of:

(B-1) preparing a water-in-oil emulsion according to the method of claim 7, and measuring the conductivity, viscosity and stabilization time of the emulsion;

(B-2) formulating the composition of any one of claims 1 to 5 into an aqueous solution (iii) having a total mass concentration of 0.3% at room temperature, measuring the interfacial tension between said aqueous solution (iii) and the oil phase used in said emulsion in step (B-1),

Wherein in the step (B-1), the stabilization time is the time from the completion of the preparation to the appearance of a significant oil-water interface of the emulsion; when the conductivity is >18mS/cm, the obtained emulsion is considered to be an oil-in-water emulsion, whereas a water-in-oil emulsion is considered to be obtained.

Technical Field

The invention relates to an oil-water emulsion emulsifier composition, in particular to a compound emulsifier composition capable of promoting oil-water rapid emulsification and preparing an ultra-low oil-water ratio water-in-oil emulsion, belonging to the field of oilfield chemistry.

background

Emulsification is one of the important mechanisms for enhanced oil recovery from compound flooding. Emulsifiers are stabilizers of emulsions and are a class of surfactants. When the emulsifier is dispersed on the surface of the dispersoid, a film or an electric double layer is formed, which charges the dispersed phase and thus prevents the droplets of the dispersed phase from coagulating with one another, so that the emulsion formed (in the context of the invention, also referred to as emulsion or emulsion) tends to be stable.

At present, external work and special emulsification equipment such as ultrasonic waves, homogenizers, microfluidizers and other high-efficiency emulsifiers are mostly needed for preparing emulsion, the equipment is expensive in manufacturing cost and high in production cost, and meanwhile, a complex and low-efficiency technological process is involved in an oil extraction process. To improve this phenomenon, mechanisms such as spontaneous emulsification or rapid emulsification have been proposed, and attempts have been made to improve this problem.

Spontaneous emulsification refers to the process of spontaneously forming an emulsion after the two liquids left to stand together undergo a flocculent phase transition without any thermodynamic or kinetic external forces. This process, although not dependent on external operations, generally takes a long time and is not suitable for industrial applications.

In contrast, in industrial processes, emulsification, also known as rapid emulsification, occurs under the combined action of a suitable surfactant and a small amount of mechanical energy (such as light shaking, stirring, or ultrasound). Fast emulsification is a unique interfacial phenomenon, which enables oil phase and water phase to naturally mix under the action of tiny external force to form emulsion. Besides energy saving, the emulsifier also has the advantages of uniform and fine emulsified particle size distribution, high emulsifying rate and the like. In the field of tertiary oil recovery, emulsification is one of important mechanisms of oil displacement, oil displacement is carried out through a proper surfactant system, crude oil is rapidly emulsified to reduce interfacial tension, emulsion viscosity is increased, oil recovery efficiency can be greatly improved at low cost, and therefore the oil displacement agent has a wide application prospect. On the other hand, the spontaneous and rapid characteristics are more and more widely regarded in the field of emulsion preparation, and become one of the hot spots of domestic and foreign research in recent years.

In combination with recent analysis and research on the phenomenon of rapid emulsification, it is now generally believed that rapid emulsification is mainly dependent on several parameters or variables: oil-water interfacial tension; the viscosity of the interface and the interior of the body; and the structure and concentration of the surfactant. The capillary number is greater when the interfacial tension is lower and the fluid viscosity is greater. And the larger the capillary number is, the higher the oil displacement efficiency is. Thus, for the use of surfactants in oil displacement, it is desirable to have a formulation: the system can quickly emulsify the crude oil, and the viscosity of the emulsion is increased.

On the other hand, oil-based drilling fluids are also called oil-based muds, and mainly refer to water-in-oil emulsified drilling fluids using oil as a continuous phase, water as a dispersed phase, and an emulsifier as a stabilizer. Compared with water-based drilling fluid, the oil-based drilling fluid has strong inhibition, can play a role in well wall stabilization and shale inhibition, is particularly suitable for water-sensitive formations with complex formation conditions, has excellent high-temperature resistance, good lubricity, extremely strong salt pollution resistance and drill chip pollution resistance, and also has the advantages of simple field maintenance, recyclable drilling fluid and the like. Since the 60's of the 20 th century, oil-based drilling fluids have developed rapidly, becoming an important means for drilling high-difficulty high-temperature deep wells, offshore drilling wells, highly-deviated directional wells, horizontal wells, various complex well sections, and protecting reservoirs. However, the existing oil-based drilling fluid also has the problems of high cost, inconvenience in logging operation, environmental pollution and the like. The oil-water ratio of the oil-based drilling fluid is reduced, so that the use cost of the oil-based drilling fluid can be effectively controlled, and the application efficiency of the oil-based drilling fluid is improved, so that how to effectively reduce the oil-water ratio of the oil-based drilling fluid, obtain the emulsified oil-based drilling fluid with the ultralow oil-water ratio, and simultaneously ensure the stability of the emulsion becomes a key factor in research and development of related emulsifiers.

Disclosure of Invention

the inventor has made extensive studies and experiments, and unexpectedly found that mixing fatty acid and polyamine in water according to a specific ratio can realize rapid emulsification of oil-water mixture, improve the stability and viscosity of emulsion, and reduce the oil-water interfacial tension to 10^-3The magnitude of mN/m; meanwhile, an ultra-low oil-water ratio water-in-oil emulsion having an oil phase content of less than 5% (volume fraction) can be prepared, and the obtained emulsion also has excellent stability.

Accordingly, in one aspect, the present invention provides an oil and water emulsion emulsifier composition comprising at least one organic acid of formula (1) and at least one polyamine of formula (2):

R₁-A₁

formula (1)

NH₂-[(CH₂)_mNH]_n-H

Formula (2)

Wherein R is₁Is a substituted or unsubstituted straight chain C₅-C₂₀A saturated or unsaturated hydrocarbon group;

A₁is carboxyl, sulfonic group, sulfuric group or phosphoric group;

Each m is independently an integer from 1 to 5;

n is an integer of 1 to 5; and is

Wherein the total molar ratio of the organic acid to the polyamine is 1:100 to 100: 1.

In another aspect, the invention provides the use of a composition of the invention in the preparation of a water-in-oil emulsion, wherein the emulsion comprises an oil phase and an aqueous phase, the volume ratio of the aqueous phase to the oil phase being from 1:1 to 100: 1.

in a further aspect, the present invention also provides a process for preparing a water-in-oil emulsion, the process comprising the steps of:

(A-1) preparing the composition of the invention into an aqueous solution (i) with a total mass concentration of 40-60% in water at normal temperature, and then further diluting the aqueous solution (i) into an aqueous solution (ii) with a total mass concentration of 2-5%; and

(A-2) adding the aqueous solution (ii) obtained in the step (A-1) into an oil-water mixture until the total mass concentration of the composition in the oil-water mixture is 0.2% -0.5%, shaking and standing,

The oil-water mixture comprises an oil phase and a water phase, wherein the oil phase is one or more of crude oil, white oil and kerosene, the water phase is deionized water and/or oilfield formation water injection, and the volume ratio of the water phase to the oil phase is 1:1-100: 1.

In yet another aspect, the present invention also provides a method for evaluating the emulsifying ability of the composition according to the present invention, comprising the steps of:

(B-1) preparing a water-in-oil emulsion according to the method of the present invention, and measuring the conductivity, viscosity and stabilization time of the emulsion;

(B-2) formulating the composition of the present invention into an aqueous solution (iii) having a total mass concentration of 0.3% at room temperature, measuring the interfacial tension between the aqueous solution (iii) and the oil phase used in the emulsion in the step (B-1),

wherein in the step (B-1), the stabilization time is the time from the completion of the preparation to the appearance of a distinct oil-water interface of the emulsion; when the conductivity is >18mS/cm (conductivity value of ultrapure water), the obtained emulsion is considered to be an oil-in-water emulsion, whereas the obtained emulsion is considered to be a water-in-oil emulsion.

Compared with the prior art, the emulsifier has the advantages of low cost and simple and quick preparation, can promote the quick emulsification of a crude oil/water system, and can prepare stable water-in-oil type emulsion with ultralow oil-water ratio; meanwhile, the invention also provides a method for conveniently evaluating the emulsion, so that a proper emulsifier can be quickly selected for oil-water systems with oil phases and water phases with different properties, and the emulsion has obvious advantages in the aspects of emulsifying, oil displacing and preparing water-in-oil drilling fluid.

Drawings

The novel features believed characteristic of the invention are set forth with particularity in the appended claims. Together with the advantages and features of the invention will be best understood from the following detailed description of illustrative embodiments when read in conjunction with the accompanying drawings, which set forth, in part, illustrative embodiments in which the principles of the invention are utilized:

FIG. 1 shows a schematic representation and a TEM image of the vesicle structure in a water-in-oil emulsion formed by the composition of the present invention when the organic acid is oleic acid and the polyamine is diethylenetriamine.

Fig. 2 is a photograph showing the macroscopic state of each emulsion in table 1.

FIG. 3 is a photograph taken by means of an optical microscope of emulsions 1 to 4 and a diagram showing the statistically obtained diameter distribution of the emulsion droplets.

Fig. 4 is a graph showing the trend of conductivity and viscosity for emulsions prepared using different polyamines/organic acids of example 2.

Fig. 5A is a photograph showing the appearance of emulsifier composition solutions formulated at different oleic acid/diethylenetriamine molar ratios.

fig. 5B is a photograph showing the appearance of emulsifier composition solutions formulated at different oleic acid/tetraethylenepentamine molar ratios.

FIG. 6 is a graph showing viscosity-shear rate curves for emulsions at different pH.

FIG. 7 is a photograph showing the effect of an additive, alkyl polyoxyethylene ether, on the emulsion emulsification rate.

Fig. 8 is a graph showing interfacial tension versus stabilization time for emulsion systems at different oleic acid/diethylenetriamine ratios.

FIG. 9 is a graph showing interfacial tension versus stabilization time for emulsion systems at different oleic acid/tetraethylenepentamine ratios.

Detailed Description

The following describes in detail specific embodiments of the present invention. It should be understood that the detailed description described herein is merely illustrative and explanatory of the invention and is not intended to limit the invention in any way.

In the context of the present invention, unless otherwise specified, the terms, definitions and test methods used follow the provisions of the national standards of the people's republic of china GB/T5327-2008 "the term surfactants", and GB/T11543-2008 "the methods for the characterization of high viscosity emulsions in surfactants, and the evaluation of their emulsifying capacity", the disclosures of which are incorporated herein in their entirety by reference.

In one aspect, the present invention provides an oil and water emulsion emulsifier composition comprising at least one organic acid of formula (1) and at least one polyamine of formula (2):

R₁-A₁

formula (1)

NH₂-[(CH₂)_mNH]_n-H

Formula (2)

Wherein R is₁is a substituted or unsubstituted straight chain C₅-C₂₀A saturated or unsaturated hydrocarbon group;

A₁Is carboxyl, sulfonic group, sulfuric group or phosphoric group;

Each m is independently an integer from 1 to 5;

n is an integer of 1 to 5; and is

Wherein the total molar ratio of the organic acid to the polyamine is 1:100 to 100: 1.

In some embodiments, the organic acid in the compositions of the present invention is a substituted or unsubstituted linear chain C₅-C₂₀Saturated or unsaturated carboxylic acids, substituted or unsubstituted straight-chain C₅-C₂₀saturated or unsaturated sulfonic acids, substituted or unsubstituted straight-chain C₅-C₂₀Saturated or unsaturated sulfuric acid or substituted or unsubstituted straight-chain C₅-C₂₀Saturated or unsaturated phosphoric acid, thereby forming vesicles by spontaneous arrangement with the polyamine represented by formula (2) at an oil-water interface, and when an emulsion membrane is damaged, emulsion particles are prevented from aggregating through interaction between the organic acid and the polyamine, thereby effectively improving the emulsion stability of the water-in-oil emulsion. FIG. 1 shows a schematic representation and transmission electron microscopy image of vesicles formed when oleic acid is the organic acid and diethylenetriamine is the polyamine, showing the hydrogen between polyamines in the emulsion formed by the composition of the inventionThe bonds form a hydrogen bond network to generate an adhesion effect, so that the stability of the vesicle structure is improved. In some embodiments, R is preferred in view of a combination of synthesis/acquisition costs, solubility in the water/oil phase, strength of interaction with polyamines, and environmental friendliness₁Is straight chain C₁₂-C₁₈Alkyl, alkenyl or dienyl, and/or A₁An organic acid which is a carboxyl group. In some embodiments, the organic acid is selected from the group consisting of: lauric acid, myristic acid, palmitic acid, oleic acid, and linoleic acid.

The polyamine shown in the formula (2) is selected to be matched with the organic acid, so that the oil-water interfacial tension is effectively reduced, and the water-in-oil emulsion with the ultralow oil-water ratio is obtained. For this purpose, in some embodiments, each m is independently an integer from 1 to 5, and n is an integer from 1 to 5. In some embodiments, each m is independently an integer from 2 to 3, and n is an integer from 2 to 4. Specifically, in some embodiments, the polyamine represented by formula (2) is one or more of ethylenediamine, diethylenetriamine, triethylenetetramine, and tetraethylenepentamine. In some embodiments, the polyamine of formula (2) is diethylenetriamine or tetraethylenepentamine.

In order to make the organic acid and the polyamine orderly arranged on an oil-water interface through interaction in the composition of the invention, obtain low oil-water interfacial tension and increase emulsion stability, the molar ratio of the organic acid to the polyamine should be between 1:100 and 100: 1. Further, in some embodiments, the total molar ratio of the organic acid to the polyamine is at least 1:20, preferably at least 1:10, more preferably at least 1:5, further preferably at least 1: 3; and/or the total molar ratio of the organic acid to the polyamine is at most 20:1, preferably at most 10:1, more preferably at most 5:1, further preferably at most 3: 1. In some embodiments, the total molar ratio of the organic acid to the polyamine is from 1:20 to 20:1, preferably from 1:10 to 10:1, more preferably from 1:5 to 5:1, and even more preferably from 1:3 to 3: 1. In some embodiments, the molar ratio of the organic acid to the polyamine is (n +1): 1. In a further embodiment, the composition of the invention has a molar ratio of the organic acid to the polyamine of 1: 1. In some embodiments, the relative amounts of the organic acid and the polyamine are determined based on the specific oil and water conditions.

In some embodiments, in order to make the oil and water emulsion emulsifier of the present invention more suitable for storage, transportation, and/or industrial practical use, the oil and water emulsion emulsifier composition of the present invention may further include at least one of the following additives: nonionic surfactant, pH regulator, inorganic salt and water phase solvent. The nature and choice of the above additives are known to the person skilled in the art; however, this does not mean any recognition that the selection of the above-mentioned additives is a routine measure. For example, when an alkyl polyoxyethylene ether is contained as a nonionic surfactant in the oil-water emulsion emulsifier composition of the present invention, a faster emulsification rate can be unexpectedly obtained, and the oil-water phase can be rapidly emulsified uniformly. In actual practice, the additives may be screened to select the most favorable composition for actual oilfield formation conditions.

In another aspect, the invention provides the use of a composition of the invention in the preparation of a water-in-oil emulsion comprising an oil phase and an aqueous phase, the volume ratio of the aqueous phase to the oil phase being from 1:1 to 100: 1. In particular, the composition of the present invention shows significant advantages in the preparation of ultra-low oil-water ratio water-in-oil emulsions, while the obtained emulsions also have excellent stability and high viscosity. In the context of the present invention, an ultra low oil-to-water ratio water-in-oil emulsion refers to a water-in-oil emulsion having a volume ratio of the aqueous phase to the oil phase of 10:1 or more, preferably 20:1 or more.

In a further aspect, the present invention also provides a process for preparing a water-in-oil emulsion, the process comprising the steps of:

(A-1) preparing the composition of the invention into an aqueous solution (i) with a total mass concentration of 40-60% in water at normal temperature, and then further diluting the aqueous solution (i) into an aqueous solution (ii) with a total mass concentration of 2-5%; and

(A-2) adding the aqueous solution (ii) obtained in the step (A-1) into an oil-water mixture until the total mass concentration of the composition in the oil-water mixture is 0.2% -0.5%, shaking and standing,

The oil-water mixture comprises an oil phase and a water phase, wherein the oil phase is one or more of crude oil, white oil and kerosene, the water phase is deionized water and/or oilfield formation water injection, and the volume ratio of the water phase to the oil phase is 1:1-100: 1.

In an embodiment of the present invention, for convenience of storage and transportation, the composition of the present invention is first formulated as an aqueous solution (i) and further diluted to an aqueous solution (ii) before use for preparation of a water-in-oil emulsion. The water from which the aqueous solutions (i) and (ii) are formulated may be deionized water and/or oilfield formation water injection, corresponding to the oil-water mixture. For practical oil recovery applications, the aqueous solution (ii) may be injected directly into the formation for oil recovery, or may be used in conjunction with conventional oil recovery agents and methods.

in yet another aspect, the present invention also provides a method for evaluating the emulsifying ability of the composition according to the present invention, comprising the steps of:

(B-1) preparing a water-in-oil emulsion according to the method of the present invention, and measuring the conductivity, viscosity and stabilization time of the emulsion;

(B-2) formulating the composition of the present invention into an aqueous solution (iii) having a total mass concentration of 0.3% at room temperature, measuring the interfacial tension between the aqueous solution (iii) and the oil phase used in the emulsion in the step (B-1),

Wherein in the step (B-1), the stabilization time is the time from the completion of the preparation to the appearance of a distinct oil-water interface of the emulsion; when the conductivity is >18mS/cm, the obtained emulsion is considered to be an oil-in-water emulsion, whereas a water-in-oil emulsion is considered to be obtained.

By the method, the emulsifying capacity of the composition of the invention under the oil-water condition of a specific oil field stratum can be rapidly evaluated at low cost, and the composition which is relatively most suitable can be rapidly screened by a high-throughput experiment. Thereby having obvious advantages in the aspects of emulsifying, displacing oil and preparing water-in-oil drilling fluid.