Preparation method of dialdehyde gemini surfactant

Abstract

The invention relates to a preparation method of a diformaldehyde gemini surfactant. Mannich reaction is adopted, a long-chain fatty amine component, glyoxal and sodium hydrogen sulfite are used as reaction raw materials, a single variable method is used for controlling reaction conditions, and the optimal conditions of the reaction are explored as follows: the reaction temperature is 60 DEG C, the reaction time is 5 h, and the molar ratio of glyoxal to sodium hydrogen sulfite is 1: 2.3. Then, all products are dissolved with trichloromethane, ethyl acetate is added into the solution to separate out the products, the products are treated through a secondary crystallization method, the product calculation yield is obtained, and the content of 1, 2-bis (dodecyl amino) ethane-1, 2-sodium disulfonate, 1, 2-bis (tetradecyl amino) ethane-1, 2-sodium disulfonate, 1, 2-bis (hexadecyl amino) ethane-1, 2-sodium disulfonate, 1, 2-bis (hexadecyl amino) ethane-1, 2-sodium disulfonate and 1, 2-bis (hexadecyl amino) ethane-1, 2-sodium disulfonate is measured. The synthetic yields of the 1, 2-sodium disulfonate are 65.8%, 67.5% and 76.8% respectively. And characterization is carried out through a nuclear magnetic resonance spectrometer and an infrared spectrometer.

Description

Technical Field

[0001] The invention provides a method for preparing a diformaldehyde Gemini surfactant, which specifically comprises the steps of carrying out a multi-component Mannich reaction using long-chain fatty amine, glyoxal and sodium bisulfite as reaction raw materials, dissolving all products with chloroform, and adding ethyl acetate to the solution for secondary crystallization. Background Art

[0002] China's demand for oil is increasing, but oil reserves are limited, so the development of oil extraction technology is extremely important. At present, some oil droplets still exist in the form of droplets in the rock pores. These oil droplets cannot be removed by secondary water injection, so tertiary oil recovery technology is needed for extraction and extraction. Chemical flooding is a new oil recovery method. Although my country's continuous research and development of chemical flooding agents has greatly improved the oil recovery rate, it has also inevitably increased the cost of mining. Therefore, in tertiary oil recovery, popularization still faces huge challenges. Therefore, it is eager to study and optimize a class of oil recovery surfactants with high universality, good performance and low cost, which can create high value.

[0003] The role of surfactants is to reduce the surface tension of solutions. The characteristic of the molecular structure of surfactants is that they have amphiphilic groups: one end is hydrophilic and the other end is hydrophobic. Surfactant solutions all show small surface tension and interfacial tension. From the perspective of the wetting principle of solid surfaces, for a certain solid surface, the smaller the surface tension of the liquid, the generally better the wetting properties. According to the wetting principle of solid surfaces, in the case of a specific solid surface, the smaller the surface tension of the liquid, the better the wetting properties of the liquid. However, wetting is only the first step in the entire cleaning process, because further other effects can only occur after the skin, hair and dirt surfaces are fully moistened. Surfactants are closely related to the application of mature oil fields. Surfactants have the ability to reduce the surface tension between interfaces (including oil and water), thereby improving oil recovery and enhancing their application in this field.

[0004] The present invention synthesizes a synthetic sulfonate gemini surfactant, which is one of the most widely used anionic surfactants, has good hydrophilicity, and exhibits excellent wettability, salt resistance and high electrolyte resistance. The synthesized novel surfactant can improve oil displacement efficiency, and the method has the advantages of low-cost synthesis, simple and easy operation, non-toxic and harmless, environmental protection, high feasibility, etc., and therefore has broad development prospects. It is widely used in oil fields due to its low adsorption loss, high interfacial activity and effective field application.

[0005] It uses a Gemini surfactant and a sulfonic acid surfactant to compound and achieve synergistic effects. After compounding and synergizing, the performance of the surfactant system is greatly improved to meet the requirements of the oil-water environment of different reservoir conditions, so that it can be better applied in the tertiary oil recovery site, and the complex block composite oil recovery effect is significantly improved. The surfactant they form has a very low CMC value and a very high interfacial activity. It can effectively reduce the water interfacial tension at a relatively low concentration, achieve an ideal oil recovery effect, and become an oil recovery agent with excellent oil recovery performance. At the same time, it also has good emulsification, wetting, and penetration effects, and can also be used as an emulsifier and wetting agent for textiles and cosmetics.

[0006] The performance of the Gemini surfactant system synthesized by the present invention is greatly improved after compounding and synergistic action, so as to meet the requirements of the oil-water environment of different reservoir conditions, so that it can be better applied in tertiary oil recovery sites, and the composite flooding effect of complex fault blocks is significantly improved. Summary of the invention

[0007] The object of the present invention is to design a method for preparing a diformaldehyde gemini surfactant. To achieve this requirement, the present invention mainly uses a long-chain fatty amine component, glyoxal and sodium bisulfite as raw materials to undergo a Mannich reaction, and then further washes and purifies the reaction to generate 1,2-bis(alkylamino)ethane-1,2-disulfonic acid sodium.

[0008] Its synthesis method mainly comprises the following steps:

[0009] Step 1: Synthesis of a series of crude products such as sodium 1,2-bis(dodecylamino)ethane-1,2-disulfonic acid. Under the condition of temperature of 60°C, the molar ratio of glyoxal: sodium bisulfite is 1:2.3, the reaction time is 5h, the sodium bisulfite is first dissolved in 5ml water, then glyoxal is added dropwise, and finally dodecylamine, tetradecylamine or hexadecylamine is added. The three substances are added to a 100mL three-necked flask, and when the temperature rises to 50°C, the three-necked flask is placed in an oil bath pot for heating, and stirred continuously for 5h under condensation reflux conditions.

[0010] Step 2: Purification of a series of products including sodium 1,2-bis(dodecylamino)ethane-1,2-disulfonate. All products were dissolved in chloroform, and ethyl acetate was added to the solution in equal proportion for secondary crystallization to obtain the final product. When the amine component ratio was dodecylamine and tetradecylamine, the final yields were 65.8%, 67.5%, and 76.8%.

[0011] In the present invention, the first step of the preparation process uses glyoxal and sodium bisulfite as reaction raw materials in a mass ratio of 1:2.3 to carry out Mannich reaction, and uses dodecylamine, tetradecylamine and hexadecylamine as amine components to condense with them. The reaction time is 5 hours and the reaction temperature is 60°C.

[0012] In the present invention, chloroform is used to dissolve all products in the second step of the preparation process, and ethyl acetate is added to the solution in equal proportion for secondary crystallization to obtain the final products of 1,2-bis(dodecylamino)ethane-1,2-sodium disulfonate, 1,2-bis(tetradecylamino)ethane-1,2-sodium disulfonate and 1,2-bis(hexadecylamino)ethane-1,2-sodium disulfonate, with yields of 65.8%, 67.5% and 76.8% respectively.

[0013] The present invention is the first to adopt the Mannich reaction to prepare the diformaldehyde gemini surfactant by multi-component reaction, and has the following outstanding advantages in the preparation process.

[0014] 1. Gemini surfactants can more effectively reduce interfacial tension due to their tighter surface arrangement; at the same time, this type of surfactant is more likely to aggregate to form micelles; it has strong viscosity characteristics; foam performance, emulsification performance, and wettability are also better; soap calcium dispersibility is stronger; and the compounding effect is better.

[0015] 2. Sulfonate Gemini surfactants are compounded with Gemini surfactants and sulfonic acid surfactants to achieve synergistic effects. After the synergistic compounding, the performance of the surfactant system is greatly improved to meet the requirements of the oil-water environment in different reservoir conditions, so that it can be better applied in tertiary oil recovery sites, and the composite oil recovery effect of complex fault blocks is significantly improved. The surfactants they form have very low CMC values ​​and high interfacial activity, and can effectively reduce water interfacial tension at a relatively low concentration to achieve an ideal oil recovery effect, becoming an oil recovery agent with excellent oil recovery performance. DETAILED DESCRIPTION

[0016] The present invention is further described below by way of implementation examples, the purpose of which is to provide a better understanding of the content of the present invention.

[0017] Embodiment 1:

[0018] Synthesis of a series of crude products such as sodium 1,2-bis(dodecylamino)ethane-1,2-disulfonate. Weigh 1.4509g of glyoxal and 2.2893g of sodium bisulfite respectively, dissolve the sodium bisulfite in 5mL of water, then drop glyoxal, and finally add dodecylamine, add the three substances into a 100mL three-necked flask, and when the temperature rises to 50°C, put the three-necked flask into an oil bath and heat it, and stir the solution continuously under condensation reflux conditions, and perform secondary crystallization after the reaction for 5h, put the three-necked flask into an oil bath that has been heated to 50°C, and stir continuously for 5h under condensation reflux conditions, and perform secondary crystallization after the reaction is completed.

[0019] Embodiment 2:

[0020] Purification of a series of products such as sodium 1,2-bis(dodecylamino)ethane-1,2-disulfonate. Stir with a glass rod until the product is completely dissolved in chloroform, the solution turns red, pour into ethyl acetate until no solid precipitates, filter to obtain the final target compound, repeat the above operation 3 times, and finally obtain a product with a purity greater than 96%.

[0021] Embodiment 3:

[0022] Synthesis of the same series of products. Under the same conditions, the raw material dodecylamine was replaced with tetradecylamine and hexadecylamine respectively, and the same operation was carried out as in the first step to synthesize the same series of products 1,2-bis(tetradecylamino)ethane-1,2-disulfonic acid sodium and 1,2-bis(hexadecylamino)ethane-1,2-disulfonic acid sodium.

Claims

1. A method for preparing a diformaldehyde gemini surfactant, which is achieved by a Mannich reaction and purified, characterized in that Follow these steps: Step 1: using glyoxal and sodium bisulfite as reaction materials at a mass ratio of 1:2.3 to carry out Mannich reaction, and using dodecylamine, tetradecylamine and hexadecylamine as amine components to condense with them. Step 2: Use chloroform to dissolve all the products, and add ethyl acetate to the solution for secondary crystallization to obtain the final product.

2. The preparation method according to step 1 of claim 1, characterized in that: The conditions are reaction temperature of 60°C and reaction time of 5h.

3. The preparation method according to step 2 of claim 1, characterized in that The mass ratio of chloroform to ethyl acetate is 1:1, and when dodecylamine, tetradecylamine and hexadecylamine are the amine components, the final yields of the product are 65.8%, 67.5% and 76.8% respectively.