Glycosyl anionic surfactant as well as preparation method and application thereof

Abstract

The invention relates to the technical field of oilfield chemistry, in particular to a glycosyl anionic surfactant and a preparation method and application thereof, and the glycosyl anionic surfactant is prepared from glucose, long-chain alkyl primary amine and succinic anhydride sodium hydroxide. The glycosyl anionic surfactant has excellent surface activity, is simple in preparation method, high in product yield, safe and reliable, can be used for oil displacement agents, polymer surface oil displacement agents, emulsifiers, discharge aiding agents, heavy oil viscosity reducers and the like, is wide in application, and meets the green development requirements of oil fields. The acid fracturing discharge aiding agent using the glycosyl anionic surfactant as a raw material can effectively reduce the surface and interfacial tension of an aqueous solution, and meets the technical specification of the acid fracturing discharge aiding agent.

Description

Technical Field

[0001] The invention relates to the technical field of oilfield chemistry, and is a sugar-based anionic surfactant, a preparation method and application thereof, and a drainage aid for acid fracturing using the sugar-based anionic surfactant as a raw material. Background Art

[0002] Surfactants have a special structure of both lipophilic and hydrophilic groups, and can be adsorbed on the oil-gas-water three-phase interface, thereby changing the wetting effect and reducing the surface interfacial tension. This property is widely used in various fields of oil and gas field development.

[0003] Acid fracturing technology is an important measure for the efficient development of oil and gas fields. It is also the main technical means to achieve the exploration and development of unconventional oil and gas resources, increase and stabilize the production of conventional oil and gas fields, and improve the effect of reservoir transformation. In the process of fracturing and acidizing, it is usually necessary to rely on the formation pressure to quickly discharge the flowback fluid from the well to the ground. When the formation pressure gradually decreases, the flowback rate decreases significantly, and the residue in the flowback fluid will cause blockage after precipitation, resulting in secondary pollution of the formation, which seriously affects the construction efficiency and the effect of fracturing and acidizing. In order to solve the problem of the difficulty of flowback fluid after fracturing and acidizing, the use of drainage aids is a conventional means. Drainage aids are one of the additives of fracturing fluid, which can effectively reduce surface tension and interfacial tension, reduce capillary resistance, increase the flowback rate and flowback rate, and thus reduce formation damage. At present, many targeted drainage aids have been formed at home and abroad, but most of them contain fluorocarbon surfactants. However, fluorocarbon surfactants have problems such as difficult degradation and persistent bioaccumulation.

[0004] In view of this, it is an urgent problem to synthesize an environmentally friendly and high-performance surfactant that can be effectively used as a drainage agent for acid fracturing. Summary of the invention

[0005] The present invention provides a sugar-based anionic surfactant and a preparation method thereof, which overcomes the deficiencies of the above-mentioned prior art and can effectively solve the problems that the surfactants and drainage aids used in the existing fracturing fluids have biological toxicity and safety risks.

[0006] One of the technical solutions of the present invention is achieved by the following measures: a sugar-based anionic surfactant is composed of glucose, long-chain alkyl primary amine, succinic anhydride and sodium hydroxide, and has a chemical structural formula of:

[0007]

[0008] Where R is C 12 To C 18 Saturated or unsaturated aliphatic hydrocarbon group.

[0009] The following is a further optimization and / or improvement of one of the above-mentioned technical solutions:

[0010] The above-mentioned sugar-based anionic surfactant is prepared by the following method:

[0011] In the first step, the required amount of glucose and long-chain alkyl primary amine are added into a first reactor, a solvent is added into the first reactor, and a reflux reaction is performed. After the reaction is complete, solid-liquid separation and drying are performed to obtain N-alkyl glucosamine;

[0012] The second step is to add the required amount of succinic anhydride and N-alkylglucosamine into the second reactor, add the solvent into the second reactor, and perform a reflux reaction;

[0013] The third step is to drop NaOH solution into the second reactor, adjust the pH value and continue the reaction. After the reaction is completed, the mixed solution in the second reactor is separated and purified to obtain a sugar-based anionic surfactant.

[0014] In the first step, the molar ratio of glucose to long-chain alkyl primary amine is 1.05 to 1.1:1.

[0015] In the above first and second steps, the solvent is dry methanol.

[0016] In the first step, the reaction conditions of the reflux reaction are a reaction temperature of 40° C. to 60° C. and a reaction time of 6 h to 8 h.

[0017] In the second step, the molar ratio of succinic anhydride to N-alkylglucosamine is 1.1 to 1.2:1.

[0018] In the above second step, the reaction conditions of the reflux reaction are reaction temperature of 40° C. to 60° C. and reaction time of 2 h to 6 h.

[0019] In the third step, NaOH solution is added dropwise to the reaction vessel, the pH value is adjusted to 7.0 to 7.5, and the reaction is continued for 1.5 to 3 hours.

[0020] In the third step, the specific operation of separation and purification is as follows: distill the mixed liquid in the second reactor under reduced pressure to remove methanol and water to obtain a viscous liquid; extract the viscous liquid with acetone to precipitate a light yellow solid, filter to remove the acetone and then vacuum dry the light yellow solid to obtain a sugar-based anionic surfactant, namely, sodium N-alkyl glucosyl butylamide.

[0021] The second technical solution of the present invention is achieved by the following measures: A method for preparing a sugar-based anionic surfactant is carried out according to the following steps:

[0022] In the first step, the required amount of glucose and long-chain alkyl primary amine are added into a first reactor, a solvent is added into the first reactor, and a reflux reaction is performed. After the reaction is complete, solid-liquid separation and drying are performed to obtain N-alkyl glucosamine;

[0023] The second step is to add the required amount of succinic anhydride and N-alkylglucosamine into the second reactor, add the solvent into the second reactor, and perform a reflux reaction;

[0024] The third step is to drop NaOH solution into the second reactor, adjust the pH value and continue the reaction. After the reaction is completed, the mixed solution in the second reactor is separated and purified to obtain a sugar-based anionic surfactant.

[0025] The third technical solution of the present invention is achieved through the following measures: application of a sugar-based anionic surfactant in a fracturing fluid additive.

[0026] The fourth technical solution of the present invention is achieved through the following measures: a drainage aid for acid fracturing, wherein the raw materials are composed of 8.0 to 9.5 parts of a sugar-based anionic surfactant, 0.5 to 2.0 parts of a head hydroxyl cationic surfactant, and the rest is water per 100 parts by mass; the sugar-based anionic surfactant, the head hydroxyl cationic surfactant and water are stirred and mixed uniformly at room temperature to obtain the drainage aid for acid fracturing.

[0027] The following is a further optimization and / or improvement of the fourth technical solution of the above invention:

[0028] The chemical structural formula of the above-mentioned head hydroxyl cationic surfactant is:

[0029]

[0030] Where R2 is C 12 To C 16 aliphatic hydrocarbon group, X is chlorine or bromine; the head hydroxy cationic surfactant is N-alkyl-N,N-dimethylhydroxyethylammonium chloride or N-alkyl-N,N-dimethylhydroxyethylammonium bromide.

[0031] The present invention provides a sugar-based anionic surfactant and a preparation method and application thereof. The sugar-based anionic surfactant has excellent surface activity, a simple preparation method, a high product yield, is safe and reliable, and can be used for oil displacement agents, polymer surface displacement agents, emulsifiers, drainage aids, heavy oil viscosity reducers, etc. It has a wide range of uses and meets the needs of green development of composite oil fields. The drainage aid for acid fracturing using the sugar-based anionic surfactant as a raw material can effectively reduce the interfacial tension of the aqueous solution and meet the technical specifications of the drainage aid for acid fracturing. DETAILED DESCRIPTION

[0032] The present invention is not limited by the following embodiments, and the specific implementation method can be determined according to the technical scheme of the present invention and the actual situation. Unless otherwise specified, the various chemical reagents and chemicals mentioned in the present invention are all known and commonly used chemical reagents and chemicals in the prior art; unless otherwise specified, the percentages in the present invention are all mass percentages; the normal temperature and room temperature in the present invention generally refer to the temperature of 15°C to 25°C, and are generally defined as 25°C.

[0033] The present invention will be further described below in conjunction with embodiments:

[0034] Example 1: The sugar-based anionic surfactant is made of glucose, long-chain alkyl primary amine, succinic anhydride and sodium hydroxide, and has the chemical structural formula:

[0035]

[0036] Where R is C 12 To C 18 Saturated or unsaturated aliphatic hydrocarbon group.

[0037] The present invention introduces a hydrophobic group and then a carboxyl group into the glucose molecule, so that the sugar-based anionic surfactant has good water solubility and excellent ability to reduce the interfacial tension of the oil-water surface. Glucose has a wide source, low cost, is environmentally friendly and easy to biodegrade.

[0038] Example 2: As an optimization of the above example, the following method was used to prepare:

[0039] In the first step, the required amount of glucose and long-chain alkyl primary amine are added into a first reactor, a solvent is added into the first reactor, and a reflux reaction is performed. After the reaction is complete, solid-liquid separation and drying are performed to obtain N-alkyl glucosamine;

[0040] The second step is to add the required amount of succinic anhydride and N-alkylglucosamine into the second reactor, add the solvent into the second reactor, and perform a reflux reaction;

[0041] The third step is to drop NaOH solution into the second reactor, adjust the pH value and continue the reaction. After the reaction is completed, the mixed solution in the second reactor is separated and purified to obtain a sugar-based anionic surfactant.

[0042] In the present invention, the reaction process for preparing the intermediate product N-alkyl glucosamine is as follows:

[0043]

[0044] The reaction process for preparing the intermediate product N-alkylglucosylbutyramic acid obtained in the second step is as follows:

[0045]

[0046] The reaction process for the preparation of the sugar-based surfactant sodium N-alkylglucosylbutyramate is as follows:

[0047]

[0048] In the above structural formula, R is C 12 To C 18 Saturated or unsaturated aliphatic hydrocarbon group.

[0049] Example 3: As an optimization of the above example, in the first step, the molar ratio of glucose to long-chain alkyl primary amine is 1.05 to 1.1:1.

[0050] Example 4: As an optimization of the above example, in the first step and the second step, the solvent is dry methanol.

[0051] Example 5: As an optimization of the above example, in the first step, the reaction conditions of the reflux reaction are a reaction temperature of 40°C to 60°C and a reaction time of 6h to 8h.

[0052] Example 6: As an optimization of the above example, in the second step, the molar ratio of succinic anhydride to N-alkylglucosamine is 1.1 to 1.2:1.

[0053] Example 7: As an optimization of the above example, in the second step, the reaction conditions of the reflux reaction are a reaction temperature of 40°C to 60°C and a reaction time of 2h to 6h.

[0054] Example 8: As an optimization of the above example, in the third step, NaOH solution is added dropwise to the reaction container, and the pH value is adjusted to 7.0 to 7.5 and the reaction is continued for 1.5 to 3 hours.

[0055] Example 9: As an optimization of the above example, in the third step, the specific operation of separation and purification is: distill the mixed liquid in the second reactor under reduced pressure to remove methanol and water to obtain a viscous liquid; extract the viscous liquid with acetone to precipitate a light yellow solid, filter out the acetone and then vacuum dry the light yellow solid to obtain a sugar-based anionic surfactant, namely sodium N-alkyl glucosyl butylamide.

[0056] Example 10: Application of the sugar-based anionic surfactant in fracturing fluid additives.

[0057] Example 11: The drainage aid for acid fracturing has the following raw materials, calculated by mass: 8.0 to 9.5 parts of a sugar-based anionic surfactant (i.e., sodium N-alkyl glucosyl butyramate), 0.5 to 2.0 parts of a head hydroxyl cationic surfactant, and the remainder being water. The drainage aid for acid fracturing is obtained by stirring and mixing the sugar-based anionic surfactant, the head hydroxyl cationic surfactant and water at room temperature to obtain a uniform mixture.

[0058] The drainage aid for acid fracturing of the present invention can be directly prepared and used on site using oilfield produced water, flowback fluid and other oilfield wastewater.

[0059] Example 12: As an optimization of the above example, the chemical structure of the head hydroxyl cationic surfactant is:

[0060]

[0061] Where R2 is C 12 To C 16 aliphatic hydrocarbon group, X is chlorine or bromine; the head hydroxy cationic surfactant is N-alkyl-N,N-dimethylhydroxyethylammonium chloride or N-alkyl-N,N-dimethylhydroxyethylammonium bromide.

[0062] Embodiment 13:

[0063] Preparation of sodium N-dodecyl glucosyl butylamide:

[0064] Weigh glucose and dodecylamine (molar ratio of 1.1:1), add into a reaction vessel, use appropriate amount of dry methanol as solvent, reflux at 45°C for 6h, cool, filter, recrystallize with anhydrous ethanol, and dry in vacuum to obtain white solid N-dodecyl glucosamine.

[0065] Weigh succinic anhydride and N-dodecyl glucosamine (molar ratio of 1.1:1), add into a reaction vessel, use appropriate amount of dry methanol as solvent, and reflux at 50°C for 4h; add 10% NaOH solution by mass to the above reaction solution, adjust the pH to 7.2 and continue to react for 2h, remove methanol and water by vacuum distillation to obtain a viscous liquid, extract with acetone, precipitate a light yellow solid, filter, and vacuum dry to obtain sodium N-dodecyl glucosyl butylamide.

[0066] Preparation of drainage agent for acid fracturing:

[0067] Weigh 9.5 parts of sodium N-dodecyl glucosyl butylamide, 0.5 parts of N-tetradecyl-N,N-dimethylhydroxyethyl ammonium bromide and 90 parts of water, stir at room temperature, and dissolve evenly to obtain 100 parts of drainage aid for acid fracturing.

[0068] The acid fracturing drainage agent was tested indoors, and the test results showed that the surface tension was 23.483 mN / m and the interfacial tension was 0.476 mN / m at a concentration of 0.3% by mass, which met the industry standards for non-fluorocarbon drainage agents.

[0069] Embodiment 14:

[0070] Preparation of sodium N-dodecyl glucosyl butylamide:

[0071] Weigh glucose and dodecylamine (molar ratio of 1.1:1), add into a reaction vessel, use appropriate amount of dry methanol as solvent, reflux at 55°C for 6h, cool, filter, recrystallize with anhydrous ethanol, and dry in vacuum to obtain white solid N-dodecyl glucosamine;

[0072] Weigh succinic anhydride and N-dodecyl glucosamine (molar ratio of 1.1:1), add into a reaction vessel, use appropriate amount of dry methanol as solvent, reflux at 50°C for 4h; add 20% NaOH solution by mass to the above reaction solution, adjust the pH to 7.3 and continue to react for 2h, remove methanol and water by vacuum distillation to obtain a viscous liquid, extract with acetone, precipitate a light yellow solid, filter, and vacuum dry to obtain sodium N-dodecyl glucosyl butylamide.

[0073] Preparation of drainage agent for acid fracturing:

[0074] Weigh 9 parts of sodium N-dodecyl glucosyl butylamide, 1 part of N-tetradecyl-N,N-dimethylhydroxyethyl ammonium bromide and 90 parts of water, stir at room temperature, and dissolve evenly to obtain 100 parts of drainage aid for acid fracturing.

[0075] The acid fracturing drainage agent was tested indoors, and the test results showed that the surface tension was 22.526 mN / m and the interfacial tension was 0.08 mN / m at a concentration of 0.3% by mass, which met the industry standards for non-fluorocarbon drainage agents.

[0076] Embodiment 15:

[0077] Preparation of sodium N-oleyl glucosyl butylamide:

[0078] Weigh glucose and oleylamine (molar ratio of 1.05:1), add into a reaction vessel, use an appropriate amount of dry methanol as solvent, reflux at 60°C for 6h, cool, filter, recrystallize with anhydrous ethanol, and vacuum dry to obtain N-oleyl glucosamine;

[0079] Weigh succinic anhydride and N-alkylglucosamine (molar ratio of 1.1:1), add into a reaction container, use appropriate amount of dry methanol as solvent, reflux at 50°C for 4 hours; add NaOH solution dropwise into the above reaction solution, adjust the pH to slightly alkaline and continue to react for 2 hours, remove methanol and water by distillation under reduced pressure to obtain a viscous liquid, extract with acetone, filter, and vacuum dry to obtain sodium N-oleyl glucosyl butylamide.

[0080] Preparation of drainage agent for acid fracturing:

[0081] Weigh 9 parts of sodium N-oleyl glucosyl butylamide, 1 part of N-dodecyl-N,N-dimethylhydroxyethyl ammonium chloride and 90 parts of water, stir at room temperature, and dissolve evenly to obtain 100 parts of drainage aid for acid fracturing.

[0082] The acid fracturing drainage agent was tested indoors, and the test results showed that the surface tension was 22.732 mN / m and the interfacial tension was 0.029 mN / m at a concentration of 0.3% by mass, which met the industry standards for non-fluorocarbon drainage agents.

[0083] Embodiment 16:

[0084] The preparation of sodium N-oleyl glucosyl butylamide is the same as in Example 15.

[0085] Preparation of drainage agent for acid fracturing:

[0086] Weigh 9 parts of sodium N-oleyl glucosyl butylamide, 1 part of N-hexadecyl-N,N-dimethylhydroxyethyl ammonium chloride and 90 parts of water, stir at room temperature, and dissolve evenly to obtain 100 parts of drainage aid for acid fracturing.

[0087] The acid fracturing drainage agent was tested indoors, and the test results showed that the surface tension was 22.423 mN / m and the interfacial tension was 0.014 mN / m at a concentration of 0.3% by mass, which met the industry standards for non-fluorocarbon drainage agents.

[0088] In summary, the sugar-based anionic surfactant of the present invention has reliable principle, simple operation, excellent performance, can be used for oil displacement agent, drainage agent, emulsifier, heavy oil viscosity reducer, etc., has a wide range of uses, and meets the green development needs of composite oil fields. The sugar-based anionic surfactant has good composite synergistic characteristics with other different types of surfactants, can effectively reduce surface interfacial tension, and significantly reduce the amount of surfactant used, reducing the cost of use. The drainage agent for acid fracturing using the sugar-based anionic surfactant as a raw material can effectively reduce the surface interfacial tension of the aqueous solution and meet the technical specifications of acid fracturing drainage agents.

[0089] The above technical features constitute the embodiments of the present invention, which have strong adaptability and implementation effect. Non-essential technical features can be added or reduced according to actual needs to meet the requirements of different situations.

Claims

1. A sugar-based anionic surfactant, characterized in that It is made of glucose, long-chain alkyl primary amine, succinic anhydride and sodium hydroxide, and its chemical structure is: Where R is C 12 To C 18 Saturated or unsaturated aliphatic hydrocarbon group.

2. The sugar-based anionic surfactant according to claim 1, characterized in that Prepared as follows: In the first step, the required amount of glucose and long-chain alkyl primary amine are added into a first reactor, a solvent is added into the first reactor, and a reflux reaction is performed. After the reaction is complete, solid-liquid separation and drying are performed to obtain N-alkyl glucosamine; The second step is to add the required amount of succinic anhydride and N-alkylglucosamine into the second reactor, add the solvent into the second reactor, and perform a reflux reaction; The third step is to drop NaOH solution into the second reactor, adjust the pH value and continue the reaction. After the reaction is completed, the mixed solution in the second reactor is separated and purified to obtain a sugar-based anionic surfactant.

3. The sugar-based anionic surfactant according to claim 2, characterized in that In the first step, the molar ratio of glucose to the long-chain alkyl primary amine is 1.05 to 1.1:1; or / and, in the first step and the second step, the solvent is dry methanol.

4. The sugar-based anionic surfactant according to claim 2 or 3, characterized in that In the first step, the reaction conditions of the reflux reaction are a reaction temperature of 40° C. to 60° C. and a reaction time of 6 h to 8 h; or / and, in the second step, a molar ratio of succinic anhydride to N-alkylglucosamine is 1.1 to 1.2:

1.

5. The sugar-based anionic surfactant according to any one of claims 2 to 4, characterized in that In the second step, the reaction conditions of the reflux reaction are a reaction temperature of 40°C to 60°C and a reaction time of 2h to 6h; or / and, in the third step, NaOH solution is added dropwise to the reaction container, the pH value is adjusted to 7.0 to 7.5, and the reaction is continued for 1.5h to 3h.

6. The sugar-based anionic surfactant according to any one of claims 2 to 5, characterized in that In the third step, the specific operation of separation and purification is: the mixed liquid in the second reactor is distilled under reduced pressure to remove methanol and water to obtain a viscous liquid; the viscous liquid is extracted with acetone to precipitate a light yellow solid, and the light yellow solid is vacuum dried after filtering to remove the acetone to obtain a sugar-based anionic surfactant.

7. A method for preparing a sugar-based anionic surfactant according to any one of claims 1 or 3 or 4 or 5 or 6, characterized in that Follow these steps: In the first step, the required amount of glucose and long-chain alkyl primary amine are added into a first reactor, a solvent is added into the first reactor, and a reflux reaction is performed. After the reaction is complete, solid-liquid separation and drying are performed to obtain N-alkyl glucosamine; The second step is to add the required amount of succinic anhydride and N-alkylglucosamine into the second reactor, add the solvent into the second reactor, and perform a reflux reaction; The third step is to drop NaOH solution into the second reactor, adjust the pH value and continue the reaction. After the reaction is completed, the mixed solution in the second reactor is separated and purified to obtain a sugar-based anionic surfactant.

8. Use of the sugar-based anionic surfactant according to any one of claims 1 to 6 in a fracturing fluid additive.

9. A drainage aid for acid fracturing using the sugar-based anionic surfactant according to any one of claims 1 to 6 as a raw material, characterized in that The raw materials are composed of 8.0 to 9.5 parts of sugar-based anionic surfactant, 0.5 to 2.0 parts of head hydroxyl cationic surfactant, and the rest of water per 100 parts by mass; the sugar-based anionic surfactant, head hydroxyl cationic surfactant and water are stirred and mixed evenly at room temperature to obtain a drainage agent for acid fracturing.

10. The drainage aid for acid fracturing according to claim 9, characterized in that The chemical structure of the hydroxyl cationic surfactant is: Where R2 is C 12 To C 16 aliphatic hydrocarbon group, X is chlorine or bromine; the head hydroxy cationic surfactant is N-alkyl-N,N-dimethylhydroxyethylammonium chloride or N-alkyl-N,N-dimethylhydroxyethylammonium bromide.

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