Sulfamic acid betaine type surfactant as well as preparation method and application thereof

Abstract

The invention relates to the technical field of oilfield chemistry, in particular to a preparation method and application of a sulfamic acid betaine type surfactant. The sulfamic acid betaine surfactant and the preparation method thereof have the advantages that the operation is simple, the product yield is high, and the product is green, biodegradable and environment-friendly; the product can be directly used without separation and purification, so that the cost is reduced. The discharge aiding agent for acid fracturing, which takes the surfactant as a main component, can effectively reduce surface and interfacial tension of fracturing fluid of oil and gas fields, and meanwhile, the use amount of the surfactant in the discharge aiding agent is low, so that the use cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of oilfield chemistry, and is an aminosulfonic acid betaine type surfactant, a preparation method and application thereof, and a drainage aid for acid fracturing. Background Art

[0002] Acid fracturing transformation technology is an important measure for the efficient development of oil and gas fields. It is 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 acid fracturing, it is usually necessary to rely on the formation pressure to quickly discharge the return fluid in the well to the ground. When the formation pressure gradually decreases, the return rate decreases significantly, and the residue in the return fluid will cause blockage after precipitation, resulting in secondary pollution of the formation, which seriously affects the construction efficiency and the effect of acid fracturing transformation. In order to solve the problem of difficulty in returning the return fluid after oil acid fracturing, the use of drainage aids is a conventional method.

[0003] A drainage aid is one of the fracturing fluid additives. Surfactants are the main components of drainage aids, which can effectively reduce surface tension and interfacial tension, reduce capillary resistance, increase flowback rate and flowback rate, and thus reduce formation damage. At present, there are many types of drainage aids used at home and abroad, but most of them are prepared by compounding fluorocarbon surfactants with other surfactants. Fluorocarbon surfactants have high surface activity and can reduce surface tension to 23mN / m. However, they are expensive, difficult to degrade, and have high biological toxicity. Therefore, the European Union has banned the use of fluorocarbon surfactants in June 2008. In view of this, the development of green and environmentally friendly drainage aid surfactants and drainage aid systems has become an urgent problem to be solved. Summary of the invention

[0004] The present invention provides an aminosulfonic acid betaine type surfactant and a preparation method and application thereof, which overcomes the deficiencies of the above-mentioned prior art and can effectively solve the problem that the existing surfactant used in drainage aids is expensive and difficult to degrade.

[0005] One of the technical solutions of the present invention is achieved by the following measures: an aminosulfonic acid betaine type surfactant, the chemical structural formula of

[0006]

[0007] Where R is C 12 To C 16 aliphatic hydrocarbon group.

[0008] The following is a further optimization and / or improvement of one of the above-mentioned technical solutions:

[0009] The aminosulfonic acid betaine type surfactant is prepared according to the following steps:

[0010] The first step is to mix the required amount of N,N-dimethyl alkyl tertiary amine and epichlorohydrin, stir evenly, and react at a required temperature to obtain an intermediate product 2,3-epoxypropyl-N,N-dimethyl long-chain alkylammonium chloride;

[0011] In the second step, the required amount of the intermediate product 2,3-epoxypropyl-N,N-dimethyl long-chain alkylammonium chloride, taurine and sodium hydroxide are dissolved in water, stirred evenly, and reacted at the required temperature to obtain an aminosulfonic acid betaine type surfactant.

[0012] In the first step, the molar ratio of N,N-dimethylalkyl tertiary amine to epichlorohydrin is 1:4 to 1:10.

[0013] In the first step, the reaction temperature is 50° C. to 80° C., and the reaction time is 1 h to 6 h.

[0014] In the above second step, the molar ratio of the intermediate product 2,3-epoxypropyl-N,N-dimethyl long-chain alkylammonium chloride, taurine and sodium hydroxide is 1:1:1.

[0015] In the above second step, the reaction temperature is 50° C. to 80° C., and the reaction time is 4 h to 12 h.

[0016] The second technical solution of the present invention is achieved by the following measures: a method for preparing an aminosulfonic acid betaine type surfactant, comprising the following steps:

[0017] The first step is to mix the required amount of N,N-dimethyl alkyl tertiary amine and epichlorohydrin, stir evenly, and react at a required temperature to obtain an intermediate product 2,3-epoxypropyl-N,N-dimethyl long-chain alkylammonium chloride;

[0018] In the second step, the required amount of the intermediate product 2,3-epoxypropyl-N,N-dimethyl long-chain alkylammonium chloride, taurine and sodium hydroxide are dissolved in water, stirred evenly, and reacted at the required temperature to obtain an aminosulfonic acid betaine type surfactant.

[0019] The third technical solution of the present invention is achieved through the following measures: application of an aminosulfonic acid betaine type surfactant in a fracturing fluid additive.

[0020] The fourth technical solution of the present invention is achieved by the following measures: a drainage aid for acid fracturing, wherein the raw materials, calculated by weight, include: 9 to 9.5 parts of anionic surfactant, 0.5 to 1 part of aminosulfonic acid betaine type surfactant, and the rest is water; the anionic surfactant, aminosulfonic acid betaine type surfactant and water are stirred and mixed uniformly at room temperature to obtain the drainage aid for acid fracturing.

[0021] The following is a further optimization and / or improvement of the fourth technical solution of the above invention:

[0022] The above anionic surfactant is sodium fatty alcohol polyoxyethylene ether carboxylate, and its chemical structural formula is:

[0023]

[0024] Where R1 is C 12 To C 18 Aliphatic hydrocarbon group, wherein n is an integer greater than or equal to 3.

[0025] The preparation method of the aminosulfonic acid betaine surfactant of the present invention is simple to operate, the product is green, environmentally friendly and biodegradable, and the product does not need to be separated and purified, can be directly used, is easy to operate and has low cost. The drainage aid for acid fracturing with the aminosulfonic acid betaine surfactant as the main component can effectively reduce the surface tension and interfacial tension of the fracturing fluid in the oil and gas field, and the dosage of the surfactant in the drainage aid for acid fracturing is low, thereby reducing the use cost. DETAILED DESCRIPTION

[0026] 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 chemical reagents and chemicals known and used in the prior art; unless otherwise specified, the percentages in the present invention are all mass percentages; unless otherwise specified, the solutions in the present invention are all aqueous solutions with water as the solvent, for example, hydrochloric acid solution is a hydrochloric acid aqueous solution; the normal temperature and room temperature in the present invention generally refer to a temperature of 15°C to 25°C, and are generally defined as 25°C.

[0027] The present invention will be further described below in conjunction with embodiments:

[0028] Example 1: The aminosulfonic acid betaine type surfactant has the chemical structural formula

[0029]

[0030] Wherein, R is an aliphatic hydrocarbon group of C12 to C16.

[0031] Example 2: As an optimization of the above example, the aminosulfonic acid betaine type surfactant is prepared according to the following steps:

[0032] The first step is to mix the required amount of N,N-dimethyl alkyl tertiary amine and epichlorohydrin, stir evenly, and react at a required temperature to obtain an intermediate product 2,3-epoxypropyl-N,N-dimethyl long-chain alkylammonium chloride;

[0033] In the second step, the required amount of the intermediate product 2,3-epoxypropyl-N,N-dimethyl long-chain alkylammonium chloride, taurine, and sodium hydroxide are dissolved in water, stirred evenly, and reacted at a required temperature to obtain an aminosulfonic acid betaine type surfactant. The aminosulfonic acid betaine type surfactant can be used directly.

[0034] Example 3: As an optimization of the above example, in the first step, the molar ratio of N,N-dimethylalkyl tertiary amine to epichlorohydrin is 1:4 to 1:10.

[0035] Example 4: As an optimization of the above example, in the first step, the reaction temperature is 50°C to 80°C, and the reaction time is 1h to 6h.

[0036] Example 5: As an optimization of the above example, in the second step, the molar ratio of the intermediate product 2,3-epoxypropyl-N,N-dimethyl long-chain alkylammonium chloride, taurine and sodium hydroxide is 1:1:1.

[0037] Example 6: As an optimization of the above example, in the second step, the reaction temperature is 50°C to 80°C, and the reaction time is 4h to 12h.

[0038] The chemical reaction process of the above preparation method is as follows:

[0039] (1) Preparation of 2,3-epoxypropyl-N,N-dimethyl long-chain alkylammonium chloride:

[0040]

[0041] (2) Preparation of aminosulfonic acid betaine type surfactant:

[0042]

[0043] The aminosulfonic acid betaine surfactant prepared by the invention has a simple preparation method, a high product yield, and a green and biodegradable product; no flammable, explosive, or volatile organic solvent is used in the synthesis process, and the product is safe and reliable; the product does not need to be separated and purified and can be used directly, thereby reducing costs and shortening the production cycle.

[0044] Embodiment 7: The preparation method of the aminosulfonic acid betaine type surfactant comprises the following steps:

[0045] The first step is to mix the required amount of N,N-dimethyl alkyl tertiary amine and epichlorohydrin, stir evenly, and react at a required temperature to obtain an intermediate product 2,3-epoxypropyl-N,N-dimethyl long-chain alkylammonium chloride;

[0046] In the second step, the required amount of the intermediate product 2,3-epoxypropyl-N,N-dimethyl long-chain alkylammonium chloride, taurine and sodium hydroxide are dissolved in water, stirred evenly, and reacted at the required temperature to obtain an aminosulfonic acid betaine type surfactant.

[0047] Example 8: Application of the aminosulfonic acid betaine type surfactant in fracturing fluid additives.

[0048] Example 9: A drainage aid for acid fracturing, the raw materials include, by mass, 9 to 9.5 parts of anionic surfactant, 0.5 to 1 part of aminosulfonic acid betaine surfactant, and the rest is water per 100 parts; the anionic surfactant, aminosulfonic acid betaine surfactant and water are stirred and mixed uniformly at room temperature to obtain the drainage aid for acid fracturing.

[0049] The drainage aid for acid fracturing of the present invention can be directly prepared from oilfield wastewater such as oilfield produced water and flowback fluid and used in acid fracturing construction.

[0050] Embodiment 10: As an optimization of the above embodiment, the anionic surfactant is sodium fatty alcohol polyoxyethylene ether carboxylate, and its chemical structural formula is:

[0051]

[0052] Where R1 is C 12 To C 18 Aliphatic hydrocarbon group, wherein n is an integer greater than or equal to 3.

[0053] The present invention provides an aminosulfonic acid betaine type surfactant and a preparation method thereof. The method is easy to operate, and the raw materials are green and degradable, and will not cause environmental pollution; no flammable, explosive, or volatile organic solvents are used in the synthesis process, which is safe and reliable; the product does not need to be separated and purified, and can be used directly, which can effectively reduce the surface tension of the aqueous solution; it is conducive to industrial production and promotion and application, and has broad market prospects. The drainage agent with the aminosulfonic acid betaine type surfactant as the main component effectively reduces the surface and interfacial tension of the fracturing fluid in the oil and gas field, and the two surfactants in the raw materials have good composite synergistic characteristics, and at the same time significantly reduces the amount of the surfactant in the drainage agent, reducing the use cost.

[0054] Embodiment 11:

[0055] Mix 1 mol of hexadecyldimethyl tertiary amine and 5.5 mol of epichlorohydrin evenly, heat to 55°C, reflux for 5 hours, cool to room temperature, filter, wash with cold acetone, and vacuum dry to obtain a white solid 2,3-epoxypropyl-N,N-dimethylhexadecylammonium chloride.

[0056] By mass, 5.0 parts of taurine were dissolved in 69.0 parts of tap water, 1.6 parts of sodium hydroxide were slowly added, stirred evenly, 14.5 parts of 2,3-epoxypropyl-N,N-dimethylhexadecylammonium chloride were added, the temperature was raised to 80°C, and the reaction was carried out for 8 hours to obtain an aqueous solution of aminosulfonic acid betaine type surfactant with a mass concentration of about 20%.

[0057] 9.5 parts of sodium lauryl alcohol polyoxyethylene ether (3) carboxylate and 2.5 parts of aminosulfonic acid betaine surfactant aqueous solution were weighed and dissolved in 88.0 parts of water. The mixture was stirred at room temperature and dissolved uniformly to prepare 100 parts of drainage aid for acid fracturing.

[0058] The laboratory test results of the acid fracturing drainage agent show that at a concentration of 0.3% by mass, the surface tension of the acid fracturing drainage agent is 23.071 mN / m, and the interfacial tension is 0.139 mN / m, which can meet the industry standards for non-fluorocarbon drainage agents.

[0059] Embodiment 12:

[0060] According to the method of Example 11, an aqueous solution of aminosulfonic acid betaine type surfactant with a mass concentration of about 20% was prepared.

[0061] 9.0 parts of sodium lauryl polyoxyethylene ether (23) carboxylate and 5.0 parts of aminosulfonic acid betaine surfactant aqueous solution were weighed and dissolved in 86.0 parts of water. The mixture was stirred at room temperature and dissolved uniformly to prepare 100 parts of drainage aid for acid fracturing.

[0062] The laboratory test results of the acid fracturing drainage agent show that at a concentration of 0.3% by mass, the surface tension of the acid fracturing drainage agent is 24.037 mN / m and the interfacial tension is 0.172 mN / m, which meets the industry standards for non-fluorocarbon drainage agents.

[0063] Embodiment 13:

[0064] 1 mol of tetradecyl dimethyl tertiary amine and 5.0 mol of epichlorohydrin were mixed evenly, heated to 50°C, refluxed for 6 hours, and epichlorohydrin was recovered by rotary evaporation to obtain a yellow viscous liquid 2,3-epoxypropyl-N,N-dimethyltetradecyl ammonium chloride.

[0065] By mass, 5.0 parts of taurine were dissolved in 64.5 parts of tap water, 1.6 parts of sodium hydroxide were slowly added, stirred evenly, 14.5 parts of 2,3-epoxypropyl-N,N-dimethyltetradecylammonium chloride were added, the temperature was raised to 60°C, and the reaction was carried out for 6 hours to obtain an aqueous solution of aminosulfonic acid betaine type surfactant with a mass concentration of about 20%.

[0066] 9.5 parts of sodium stearyl alcohol polyoxyethylene ether (9) carboxylate and 2.5 parts of aminosulfonic acid betaine surfactant aqueous solution were weighed and dissolved in 88.0 parts of water. The mixture was stirred at room temperature and dissolved uniformly to prepare 100 parts of drainage aid for acid fracturing.

[0067] The laboratory test results of the acid fracturing drainage agent show that at a concentration of 0.3% by mass, the surface tension of the acid fracturing drainage agent is 23.738 mN / m and the interfacial tension is 0.039 mN / m, which can meet the industry standards for non-fluorocarbon drainage agents.

[0068] Embodiment 14:

[0069] 1 mol of dodecyldimethyl tertiary amine and 6.0 mol of epichlorohydrin were mixed evenly, heated to 50°C, refluxed for 6 hours, and epichlorohydrin was recovered by rotary evaporation to obtain a yellow viscous liquid 2,3-epoxypropyl-N,N-dimethyldodecylammonium chloride.

[0070] By mass, 5.0 parts of taurine were dissolved in 60.0 parts of tap water, 1.6 parts of sodium hydroxide were slowly added, stirred evenly, 14.5 parts of 2,3-epoxypropyl-N,N-dimethyldodecylammonium chloride were added, the temperature was raised to 60°C, and the reaction was carried out for 12 hours to obtain an aqueous solution of aminosulfonic acid betaine type surfactant with a mass concentration of about 20%.

[0071] 9.5 parts of sodium hexadecanol polyoxyethylene ether (20) carboxylate and 2.5 parts of aminosulfonic acid betaine surfactant aqueous solution were weighed by mass, dissolved in 88.0 parts of water, stirred at room temperature, and dissolved uniformly to prepare 100 parts of acid fracturing drainage agent.

[0072] The laboratory test results of the acid fracturing drainage agent show that at a concentration of 0.3% by mass, the surface tension of the acid fracturing drainage agent is 23.894 mN / m and the interfacial tension is 0.134 mN / m, which meets the industry standards for non-fluorocarbon drainage agents.

[0073] In summary, the present invention provides an aminosulfonic acid betaine surfactant and a preparation method thereof, the preparation process is simple to operate, the product yield is high, the product is biodegradable, green and environmentally friendly, and does not require separation and purification and can be used directly. The acid fracturing drainage agent with the aminosulfonic acid betaine surfactant as the main component can effectively reduce the surface and interfacial tension of the fracturing fluid in the oil and gas field, and at the same time, the amount of the surfactant in the acid fracturing drainage agent is low, which reduces the use cost.

[0074] 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 sulfamic acid betaine type surfactant, characterized in that The chemical structure is Where R is C 12 To C 16 aliphatic hydrocarbon group.

2. The aminosulfonic acid betaine type surfactant according to claim 1, characterized in that Prepared according to the following steps: The first step is to mix the required amount of N,N-dimethyl alkyl tertiary amine and epichlorohydrin, stir evenly, and react at a required temperature to obtain an intermediate product 2,3-epoxypropyl-N,N-dimethyl long-chain alkylammonium chloride; In the second step, the required amount of the intermediate product 2,3-epoxypropyl-N,N-dimethyl long-chain alkylammonium chloride, taurine and sodium hydroxide are dissolved in water, stirred evenly, and reacted at the required temperature to obtain an aminosulfonic acid betaine type surfactant.

3. The aminosulfonic acid betaine type surfactant according to claim 2, characterized in that In the first step, the molar ratio of N,N-dimethylalkyl tertiary amine to epichlorohydrin is 1:4 to 1:

10.

4. The aminosulfonic acid betaine type surfactant according to claim 2 or 3, characterized in that In the first step, the reaction temperature is 50° C. to 80° C., and the reaction time is 1 h to 6 h.

5. The aminosulfonic acid betaine type surfactant according to any one of claims 2 to 4, characterized in that In the second step, the molar ratio of the intermediate product 2,3-epoxypropyl-N,N-dimethyl long-chain alkylammonium chloride, taurine and sodium hydroxide is 1:1:

1.

6. The aminosulfonic acid betaine type surfactant according to any one of claims 2 to 5, characterized in that In the second step, the reaction temperature is 50° C. to 80° C., and the reaction time is 4 h to 12 h.

7. A method for preparing an aminosulfonic acid betaine surfactant according to any one of claims 3 to 6, characterized in that The following steps are involved: The first step is to mix the required amount of N,N-dimethyl alkyl tertiary amine and epichlorohydrin, stir evenly, and react at a required temperature to obtain an intermediate product 2,3-epoxypropyl-N,N-dimethyl long-chain alkylammonium chloride; In the second step, the required amount of the intermediate product 2,3-epoxypropyl-N,N-dimethyl long-chain alkylammonium chloride, taurine and sodium hydroxide are dissolved in water, stirred evenly, and reacted at the required temperature to obtain an aminosulfonic acid betaine type surfactant.

8. Use of the aminosulfonic acid betaine type surfactant according to any one of claims 1 to 6 in a fracturing fluid additive.

9. A drainage aid for acid fracturing using the aminosulfonic acid betaine type surfactant according to any one of claims 1 to 6 as a raw material, characterized in that The raw materials include, by weight, 9 to 9.5 parts of anionic surfactant, 0.5 to 1 part of aminosulfonic acid betaine surfactant, and the rest of water. The anionic surfactant, aminosulfonic acid betaine surfactant and water are stirred and mixed uniformly 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 anionic surfactant is sodium fatty alcohol polyoxyethylene ether carboxylate, and its chemical structure is: Where R1 is C 12 To C 18 Aliphatic hydrocarbon group, wherein n is an integer greater than or equal to 3.

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