Hydrolysis-resistant organosilicon nonionic surfactant and preparation method thereof

Abstract

The invention relates to the technical field of oil field chemicals, and discloses a hydrolysis-resistant organosilicon nonionic surfactant and a preparation method thereof. The problems that in the prior art, due to retention of fracturing fluid in the flowback process, the stratum permeability is reduced, and the oil and gas development effect is affected are solved. The technical scheme adopted by the invention is as follows: weighing 10-15 parts of acrylic acid; 60 to 70 parts of octylphenol polyoxyethylene ether; the preparation method comprises the following steps: uniformly mixing the following components in parts by weight: 20-30 parts of sodium hydroxide, 0.06-0.30 part of hydroquinone and 0.6-1.8 parts of p Introducing nitrogen and heating for reaction; adding 0.05% dichloromethane for dissolving, adjusting the solution to be neutral by using a sodium hydroxide solution, and carrying out reduced pressure distillation at 45 DEG C; after the reaction is finished, adding 5 parts of isopropanol and 0.005 part of chloroplatinic acid hexahydrate, uniformly mixing, introducing nitrogen, heating for half an hour, dropwise adding heptamethyltrisiloxane at a constant speed, controlling the reaction temperature at 80-120 DEG C, and reacting for 5-7 hours to obtain brownish yellow viscous liquid; and carrying out reduced pressure distillation on the brownish yellow viscous liquid at 45 DEG C.

Description

Technical Field

[0001] The invention relates to the technical field of oilfield chemicals, and in particular to a hydrolysis-resistant organic silicon nonionic surfactant and a preparation method thereof. Background Art

[0002] According to the oil and gas resource evaluation of the Ministry of Land and Resources, tight oil accounts for 2 / 5 of my country's recoverable oil reserves. With the continuous growth of global energy demand, tight oil has become a very realistic oil replacement resource. Tight oil reservoirs have low or no natural production capacity, and are usually developed using hydraulic fracturing technology. During the fracturing process, the fracturing fluid invades the reservoir matrix to increase the water saturation of the reservoir. When the fracture is completed and the flowback begins, the capillary force will make it difficult for the invading fluid to flow back due to the poor porosity and permeability characteristics of the low permeability reservoir to be improved, causing it to be retained in the reservoir matrix. If the fracturing fluid cannot be discharged from the matrix in time, water lock damage will occur under the action of capillary force, reducing the fracturing production increase effect. Water lock damage refers to the phenomenon that when two or more phases of fluid coexist in a porous medium, the invading water phase will produce additional flow resistance to the oil phase under the action of capillary force, thereby reducing the permeability of the oil phase.

[0003] The most effective way to increase the flowback rate is to add drainage aids. Fracturing fluid drainage aids are usually compounded from two or more surfactants. Their main mechanism of action is to reduce the surface tension of the flowback fluid and the oil-water interfacial tension, increase the contact angle of the reservoir surface, and achieve the purpose of reducing capillary force and increasing the flowback rate of the fracturing fluid.

[0004] The article is titled "Synthesis and Performance Study of Phosphate-Type Polyether Modified Trisiloxane Surfactant", which discloses the synthesis and performance test of a trisiloxane surfactant. The problem is that the surface tension of the surfactant solution rises sharply to around 40mN / m within 5 days under strong acid and strong alkaline environments. The surface tension changes greatly, the stability is poor, the degree of hydrolysis is large, and it is difficult to adapt to complex formations. In addition, benzene is used as a solvent, which is a harmful chemical that can easily cause a variety of diseases. Summary of the invention

[0005] The present invention provides a hydrolysis-resistant organosilicon nonionic surfactant and a preparation method thereof to solve the problem that the fracturing fluid is retained in the flowback process in the prior art, resulting in a decrease in formation permeability and affecting the effect of oil and gas development.

[0006] To achieve the above object, the technical solution of the present invention is: a hydrolysis-resistant organic silicon nonionic surfactant, the surfactant comprising the following raw materials in parts by weight:

[0007] 10-15 parts of acrylic acid;

[0008] Octylphenol polyoxyethylene ether 60-70 parts;

[0009] 10-15 parts of heptamethyltrisiloxane;

[0010] 0.06 to 0.30 parts of hydroquinone;

[0011] 0.6 to 1.8 parts of p-toluenesulfonic acid;

[0012] 0.003-0.006 parts of chloroplatinic acid hexahydrate;

[0013] 4 to 7 parts of isopropyl alcohol.

[0014] A preparation method of a hydrolysis-resistant organosilicon nonionic surfactant comprises the following steps:

[0015] S1. Weigh acrylic acid, octylphenol polyoxyethylene ether, hydroquinone, and p-toluenesulfonic acid and mix them evenly; introduce nitrogen and raise the temperature to 90°C for 6 hours;

[0016] S2. After the reaction is completed, dichloromethane is added to dissolve, sodium hydroxide solution is used to adjust to neutral, and distilled under reduced pressure at 45 ° C;

[0017] S3. After the reaction is completed, isopropanol and chloroplatinic acid hexahydrate are added and mixed evenly, nitrogen is introduced, and after heating for half an hour, heptamethyltrisiloxane is added dropwise at a uniform rate, and the reaction temperature is controlled at 80 to 120° C. and the reaction is carried out for 5 to 7 hours to obtain a brown-yellow viscous liquid;

[0018] S4. Distill the brown-yellow viscous liquid under reduced pressure at 45°C.

[0019] Further, the concentration of sodium hydroxide in step S2 is 0.05%.

[0020] Compared with the prior art, the invention has the beneficial effects.

[0021] 1. The surfactant prepared by the present invention can improve its heat resistance, hydrolysis resistance, salt resistance, chemical resistance and the like, and reduce the surface tension due to the addition of heptamethyl trisiloxane and octylphenol polyoxyethylene ether.

[0022] 2. The more oxygen on the hydrophilic group of the monomer molecule, the easier it is to form more hydrogen bonds with water, and the better the water solubility. Since octylphenol polyoxyethylene ether contains a large number of polyoxyethylene groups, it has good water solubility. In aqueous solution, the hydrophobic part aggregates and associates through non-covalent bonds to form a surfactant micelle structure, greatly reducing the critical micelle concentration of the surfactant.

[0023] 3. The organosilicon surfactant synthesized by the present invention uses isopropanol as a solvent in the synthesis process, which is small in amount and non-toxic, and can be removed by rotary evaporation at the end of the synthesis of the product. The surface tension of the product solution can maintain the surface tension below 30mN / m within 10 days in both strong acid and strong alkali solution systems, has strong stability, and has good hydrolysis resistance. The synthetic raw materials have the advantages of wide sources and low cost.

[0024] 4. The octylphenol polyoxyethylene ether product used in the present invention is low in price, widely available, has good surface activity, can significantly reduce the surface tension of the liquid, and has many abilities such as wetting, emulsification, foaming and dispersion. It exists stably in emulsions, suspensions and colloid systems.

[0025] 5. The heptamethyl trisiloxane used in the present invention can effectively reduce the surface tension of the liquid, thereby improving its performance in the surface coating and wetting process. Due to its low surface tension, heptamethyl trisiloxane can effectively reduce the surface tension of the liquid, thereby improving its performance in the surface coating and wetting process. Compared with other organic compounds, heptamethyl trisiloxane generally has a lower environmental impact, is easy to degrade and handle, and is environmentally friendly.

[0026] 6. The method of the present invention adopts hydrosilylation reaction and esterification reaction. The reaction conditions are easy to operate, the temperature is low, the required reaction device is simple, and the conversion rate of the product is high. No by-products are generated in the process. The solvent is isopropanol, which is non-toxic, harmless and environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a diagram of hydrolysis resistance.

[0028] Figure 2 The infrared spectra of the intermediate (first step) and the hydrolysis-resistant silicone active surfactant (second step). DETAILED DESCRIPTION

[0029] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with embodiments, and the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] Description of raw materials of the present invention:

[0031] Acrylic acid (AM) has a wide range of uses. It can be used as a raw material for organic synthesis and a raw material for polymer materials. It has good chemical stability and is not easy to decompose. It is stable under various environmental conditions. In many cases, acrylic acid can be used as a corrosion-resistant material. Acrylic acid can form a strong polymer through polymerization reaction, which is used to manufacture materials of various shapes and structures. Acrylic polymers usually have good transparency and are suitable for applications that require transparent materials. Acrylic acid and its polymers are widely used in industry to manufacture plastics, coatings, adhesives, fibers, etc., and have good weather resistance and mechanical strength. Transparent acrylic polymers are often used to manufacture medical devices and equipment, such as test tubes, transparent containers, etc.

[0032] Octylphenol polyoxyethylene ether is a common chemical substance in the chemical and industrial fields with multiple advantages and wide applications. Octylphenol polyoxyethylene ether has good surface activity in water, can effectively reduce the surface tension of liquids, and is conducive to emulsification and dispersion. It can be well dissolved in water and many organic solvents, which makes it well applicable in the preparation and application process. Octylphenol polyoxyethylene ether is generally stable under various temperature and pH conditions, which makes its application in different processes more reliable. At the recommended concentration, octylphenol polyoxyethylene ether is generally low in toxicity and has little impact on the environment and human health. Due to its excellent surface activity and emulsification ability, octylphenol polyoxyethylene ether is often used as an ingredient in industrial cleaners for removing oil and dirt. In the preparation of dyes and pigments, octylphenol polyoxyethylene ether can be used as a dispersant to help stabilize the dispersion state of pigments. In agriculture, octylphenol polyoxyethylene ether can be used as a dispersant and emulsifier for pesticides and fertilizers to improve their stability and effectiveness.

[0033] Due to its special molecular structure, heptamethyl trisiloxane presents an umbrella-shaped distribution at the air-water interface, which can greatly reduce the surface tension of the aqueous solution. Due to the stability of its silicon-oxygen bond, heptamethyl trisiloxane has high high temperature resistance and is suitable for applications in high temperature environments. Heptamethyl trisiloxane is stable in many chemical substances and has good chemical inertness and corrosion resistance. Due to the stability of the silicon-oxygen bond, heptamethyl trisiloxane has antioxidant and anti-aging properties. Heptamethyl trisiloxane is often used as a base oil or emulsifier to help adjust the texture of the product and provide a lubricating feel, and it also has an anti-aging effect. Adding heptamethyl trisiloxane to coatings and paints can improve the smoothness and wear resistance of the coating surface and improve the performance of the coating. In the manufacture of medical devices, heptamethyl trisiloxane can be used as a lubricant for medical devices to reduce friction and improve the smoothness of device insertion and operation.

[0034] The surfactant provided by the present invention has the following mechanism: compared with conventional surfactants, the organosilicon surfactant with seven methyl groups can quickly form a tight adsorption film on the interface of soda and water, showing a strong ability to reduce surface tension and a strong response to external stimuli, especially in harsh formation environments and when fracturing fluid is returned, it has great application potential. Heptamethyl trisiloxane is easily hydrolyzed in an acidic or alkaline environment, resulting in a decrease in its function of reducing surface tension. Therefore, after esterification with acrylic acid by octylphenol polyoxyethylene ether, separation and purification are carried out with heptamethyl trisiloxane for hydrosilylation reaction. The surfactant contains an umbrella-shaped heptamethyl functional group and shows high surface activity. In an aqueous solution, it will be arranged on the surface of the solution in a directional manner, and the oxygen atoms on its Si-O-Si-O-Si main chain can form hydrogen bonds with water molecules, prompting it to spread into a monolayer, and the hydrophobic siloxane lies on the surface, and the seven methyl groups connected to the silicon atoms are umbrella-shaped and extend toward the air, thereby covering the surface of the solution and reducing the surface tension.

[0035] The present invention is described in detail below by way of examples:

[0036] Example 1

[0037] A hydrolysis-resistant organosilicon nonionic surfactant, comprising the following raw materials in parts by weight:

[0038] 10 parts of acrylic acid; 60 parts of octylphenol polyoxyethylene ether; 10 parts of heptamethyl trisiloxane; 0.06 parts of hydroquinone; 0.6 parts of p-toluenesulfonic acid; 0.003 parts of chloroplatinic acid hexahydrate; 4 parts of isopropanol.

[0039] The preparation method is:

[0040] S1. Octylphenol polyoxyethylene ether, acrylic acid, hydroquinone and p-toluenesulfonic acid were added to the reactor, mixed evenly, and nitrogen was passed for half an hour to remove oxygen and the temperature was raised to 90°C and the reaction was carried out for 6 hours;

[0041] S2. After the reaction is completed, a certain amount of dichloromethane is added to the product to dissolve, and a 0.05% sodium hydroxide solution is used to adjust the solution to neutral, and distilled under reduced pressure at 45°C;

[0042] S3. Chloroplatinic acid hexahydrate and isopropanol solution were added to the reaction solution and mixed evenly, nitrogen was introduced, and after heating for half an hour, heptamethyltrisiloxane was added dropwise at a uniform rate, and the reaction temperature was controlled at 90 ° C. The reaction was continued for 6 hours to obtain a brown viscous liquid;

[0043] S4. Set the temperature to 45°C and perform reduced pressure distillation to obtain the target surfactant.

[0044] Take 0.3 g of the target surfactant prepared in Example 1, add water to dissolve and shake well, place at room temperature, use a surface tension meter to test its surface tension, measure three times in a row and take the average value; the surface tension obtained by testing is 25.25 mN / m, which has the ability to significantly reduce surface tension.

[0045] Embodiment 2:

[0046] A hydrolysis-resistant organosilicon nonionic surfactant, comprising the following raw materials in parts by weight:

[0047] 15 parts of acrylic acid; 70 parts of octylphenol polyoxyethylene ether; 15 parts of heptamethyl trisiloxane; 0.30 parts of hydroquinone; 1.8 parts of p-toluenesulfonic acid; 0.006 parts of chloroplatinic acid hexahydrate, and 7 parts of isopropyl alcohol.

[0048] The preparation method is:

[0049] S1. Octylphenol polyoxyethylene ether, acrylic acid, hydroquinone and p-toluenesulfonic acid were added to the reactor and mixed evenly. Nitrogen was passed for half an hour to remove oxygen and the temperature was raised to 100 ° C and the reaction was carried out for 6 hours.

[0050] S2. Add a certain amount of dichloromethane to the product to dissolve it, use 0.05% sodium hydroxide solution, adjust the solution to neutral, set the temperature to 45 ° C and distill under reduced pressure;

[0051] S3. To the reaction solution, 0.05 mol / L of chloroplatinic acid hexahydrate and isopropanol solution were added and mixed evenly, nitrogen was introduced, and after heating for half an hour, heptamethyltrisiloxane was added dropwise at a uniform rate, and the reaction temperature was controlled at 110 ° C. The reaction was continued for 7h to obtain a brown-yellow viscous liquid;

[0052] S4. Set the temperature to 45°C and perform reduced pressure distillation to obtain the target surfactant.

[0053] Take 0.3 g of the surfactant prepared in Example 2, dissolve it in water and shake it thoroughly, place it at room temperature, and use a surface tension meter to test its surface tension. Measure it three times in a row and take the average value; the test shows that the surface tension is 25.28 mN / m, which has the ability to significantly reduce surface tension.

[0054] Embodiment 3:

[0055] A hydrolysis-resistant organosilicon nonionic surfactant, comprising the following raw materials in parts by weight:

[0056] 13 parts of acrylic acid; 65 parts of octylphenol polyoxyethylene ether; 13 parts of heptamethyl trisiloxane; 0.1 parts of hydroquinone; 1.2 parts of p-toluenesulfonic acid; 0.004 parts of chloroplatinic acid hexahydrate, and 5 parts of isopropyl alcohol.

[0057] The preparation method is:

[0058] S1. Octylphenol polyoxyethylene ether, acrylic acid, hydroquinone and p-toluenesulfonic acid were added to the reactor and mixed evenly, nitrogen was passed for half an hour to remove oxygen and the temperature was raised to 110°C and the reaction was carried out for 6 hours;

[0059] S2. Add a certain amount of dichloromethane to the product to dissolve it, use 0.05% sodium hydroxide solution, adjust the solution to neutral, set the temperature to 45 ° C and distill under reduced pressure;

[0060] S3. To the reaction solution, 0.05 mol / L of chloroplatinic acid hexahydrate and isopropanol solution were added and mixed evenly, nitrogen was introduced, and after heating for half an hour, heptamethyltrisiloxane was added dropwise at a uniform rate, and the reaction temperature was controlled at 80 ° C. The reaction was allowed to react for 5 h to obtain a brown viscous liquid;

[0061] S4. Set the temperature to 45°C and perform reduced pressure distillation to obtain the target surfactant.

[0062] Take 0.3 g of the surfactant prepared in Example 3, dissolve it in water and shake it thoroughly, place it at room temperature, and use a surface tension meter to test its surface tension. Measure it three times in a row and take the average value. The test shows that the surface tension is 26.75 mN / m, which has the ability to significantly reduce surface tension.

[0063] Example 4

[0064] A hydrolysis-resistant organosilicon nonionic surfactant, comprising the following raw materials in parts by weight:

[0065] 14 parts of acrylic acid; 68 parts of octylphenol polyoxyethylene ether; 11 parts of heptamethyl trisiloxane; 0.3 parts of hydroquinone; 1.6 parts of p-toluenesulfonic acid; 0.005 parts of chloroplatinic acid hexahydrate, and 5 parts of isopropyl alcohol.

[0066] The preparation method is:

[0067] S1. Add octylphenol polyoxyethylene ether, acrylic acid, hydroquinone and p-toluenesulfonic acid to the reactor and mix them evenly. Pass nitrogen for half an hour to remove oxygen and heat to 110°C for 6 hours.

[0068] S2. Add a certain amount of dichloromethane to the product to dissolve it, use 0.05% sodium hydroxide solution, adjust the solution to neutral, set the temperature to 45 ° C and distill under reduced pressure;

[0069] S3. To the reaction solution, 0.05 mol / L of chloroplatinic acid hexahydrate and isopropanol solution were added and mixed evenly, nitrogen was introduced, and after heating for half an hour, heptamethyltrisiloxane was added dropwise at a uniform rate, and the reaction temperature was controlled at 120 ° C. The reaction was continued for 6 hours to obtain a brown viscous liquid;

[0070] S4. Set the temperature to 45°C and perform reduced pressure distillation to obtain the target surfactant.

[0071] Take 0.3 g of the surfactant prepared in Example 3, dissolve it in water and shake it thoroughly, place it at room temperature, and use a surface tension meter to test its surface tension. Measure it three times in a row and take the average value. The test shows that the surface tension is 26.95 mN / m, which has the ability to significantly reduce surface tension.

[0072] Example 5

[0073] A hydrolysis-resistant organosilicon nonionic surfactant, comprising the following raw materials in parts by weight:

[0074] 14 parts of acrylic acid; 66 parts of octylphenol polyoxyethylene ether; 12 parts of heptamethyltrisiloxane; 0.2 parts of hydroquinone; 1.1 parts of p-toluenesulfonic acid; 0.005 parts of chloroplatinic acid hexahydrate, and 5 parts of isopropyl alcohol.

[0075] The preparation method is:

[0076] S1. Octylphenol polyoxyethylene ether, acrylic acid, hydroquinone and p-toluenesulfonic acid were added to the reactor and mixed evenly, nitrogen was passed for half an hour to remove oxygen and the temperature was raised to 110°C and the reaction was carried out for 6 hours;

[0077] S2. After the reaction is completed, a certain amount of dichloromethane is added to the product to dissolve, and a 0.05% sodium hydroxide solution is used to adjust the solution to be neutral, and the temperature is set to 45 ° C for reduced pressure distillation;

[0078] S3. After the reaction is completed, add 0.05 mol / L hexahydrate chloroplatinic acid and isopropanol solution and mix evenly, introduce nitrogen, heat for half an hour, uniformly drip heptamethyltrisiloxane, control the reaction temperature at 100°C, react for 5 hours, and obtain a brown-yellow viscous liquid.

[0079] S4. Set the temperature to 45°C and perform reduced pressure distillation to obtain the target surfactant.

[0080] Take 0.3g of the surfactant prepared in Example 5, dissolve it in water and shake it thoroughly, place it at room temperature, use 0.05% sodium hydroxide and hydrochloric acid to adjust the pH to 12 and 2; use a surface tension meter to test its surface tension, and measure it three times in a row to get the average value. The surface tension change obtained by the test is as follows Figure 1 As shown in the hydrolysis resistance effect diagram, it has obvious hydrolysis resistance.

[0081] The present invention also provides an illustrative infrared spectrum of the intermediate and the hydrolysis-resistant organosilicon surfactant, see Figure 2 .

[0082] Figure 2 The infrared spectra of the intermediate and the organosilicon active surfactant prepared in Example 1 are shown in FIG. Figure 2It can be seen that the infrared spectra of the first-step intermediate and the second-step organosilicon surfactant provided by the present invention are not much different, and the main difference is that the infrared spectra of the first-step intermediate at 1720 cm -1 The C=O stretching vibration peak at 1640 cm -1 The C=C at the esterification reaction successfully occurred. -1 The C=C at 840 cm-1 undergoes hydrosilylation and the bond disappears. -1 and 1251cm -1 The stretching vibration peaks and bending vibration peaks of Si-C appear.

[0083] The above detailed description of the preferred embodiments of the present invention is only used to help understand the present invention, and is not intended to limit the present invention. Any local modification or replacement within the technical scope disclosed by the present invention by anyone familiar with the technology should be included in the scope of the present invention.

Claims

1. A hydrolysis-resistant organosilicon nonionic surfactant, characterized in that , the surfactant includes the following raw materials in parts by weight: 10-15 parts of acrylic acid; Octylphenol polyoxyethylene ether 60-70 parts; 10-15 parts of heptamethyltrisiloxane; 0.06 to 0.30 parts of hydroquinone; 0.6 to 1.8 parts of p-toluenesulfonic acid; 0.003-0.006 parts of chloroplatinic acid hexahydrate; 4 to 7 parts of isopropyl alcohol.

2. The preparation of a hydrolysis-resistant organosilicon nonionic surfactant according to claim 1, characterized in that: The following steps are involved: S1. Weigh acrylic acid, octylphenol polyoxyethylene ether, hydroquinone, and p-toluenesulfonic acid and mix them evenly; introduce nitrogen and raise the temperature to 90°C for 6 hours; S2. After the reaction is completed, dichloromethane is added to dissolve, sodium hydroxide solution is used to adjust to neutral, and distilled under reduced pressure at 45°C; S3. After the reaction is completed, add isopropanol and chloroplatinic acid hexahydrate and mix well, introduce nitrogen, heat for half an hour, uniformly drip heptamethyltrisiloxane, control the reaction temperature at 80-120°C, react for 5-7h, and obtain a brown-yellow viscous liquid; S4. Distill the brown-yellow viscous liquid under reduced pressure at 45°C.

3. The preparation of a hydrolysis-resistant organosilicon nonionic surfactant according to claim 1, characterized in that: The concentration of sodium hydroxide in step S2 is 0.05%.

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