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CN-121975507-A - Amphoteric surfactant and preparation method and application thereof

CN121975507ACN 121975507 ACN121975507 ACN 121975507ACN-121975507-A

Abstract

The invention provides an ampholytic surfactant, a preparation method and application thereof, and belongs to the technical field of oilfield chemistry. The amphoteric surfactant comprises, by mass, 3-8% of a main body of a sulfonic acid-carboxylic acid type amphoteric surfactant, 1-3% of a gemini type organosilicon surfactant, 2-5% of a nonionic emulsifier, 4-7% of an environment-friendly organic antiscaling agent, 1-2% of a macromolecular foam stabilizer and the balance of water. According to the invention, the main body of the sulfonic acid-carboxylic acid type amphoteric surfactant is compounded with the gemini type organosilicon surfactant, so that ultra-low interfacial tension (less than or equal to 10 ‑3 mN/m) can be kept under high mineralization, the environment-friendly organic antiscalant and the macromolecular foam stabilizer cooperate, thus not only preventing inorganic scale from blocking, but also enhancing foam stability and improving oil displacement efficiency, and the whole system of the amphoteric surfactant has good compatibility, can be compounded with a polymer oil displacement agent (such as HPAM) for use, and has no layering and precipitation phenomena.

Inventors

  • Cui Xinzhou
  • LU CHUNXIAO
  • ZHANG XINGSHUAI
  • MA RUI
  • LI ZHIQIANG
  • XU GUOKUN
  • ZENG YONG

Assignees

  • 山东中曼新材料科技有限公司

Dates

Publication Date
20260505
Application Date
20260126

Claims (10)

  1. 1. The amphoteric surfactant is characterized by comprising the following components in percentage by mass: 3-8% of a main body of a sulfonic acid-carboxylic acid type amphoteric surfactant, 1-3% of a gemini type organic silicon surfactant, 2-5% of a nonionic emulsifier, 4-7% of an environment-friendly organic antiscaling agent, 1-2% of a macromolecular foam stabilizer and the balance of water; The sulfonic acid-carboxylic acid type amphoteric surfactant body is prepared by a method comprising the following steps: Mixing alkylphenol ethoxylates, inorganic alkaline substances and an organic solvent for hydrolysis reaction to obtain a hydrolysis product; carboxylation reaction is carried out on the hydrolysate and chloroacetic acid to obtain a carboxymethylation intermediate; mixing the carboxymethylation intermediate, epichlorohydrin and sodium isethionate for etherification and sulfonation reaction to obtain the main body of the sulfonic acid-carboxylic acid type amphoteric surfactant; the molecular weight of the macromolecular foam stabilizer is 10,000-3,000,000 g/mol.
  2. 2. The amphoteric surfactant according to claim 1, comprising the following components in mass percent: Sulfonic acid-carboxylic acid type amphoteric surfactant main body 5%, gemini type organosilicon surfactant 2%, nonionic emulsifier 3%, environment-friendly organic antiscaling agent 5%, macromolecular foam stabilizer 1.5% and the balance of water.
  3. 3. The amphoteric surfactant according to claim 1 or 2, wherein the alkylphenol ethoxylate comprises nonylphenol ethoxylate.
  4. 4. The amphoteric surfactant of claim 1, wherein the gemini silicone surfactant comprises one or more of a sulfobetaine-type gemini silicone surfactant, a quaternary ammonium salt-type gemini silicone surfactant, and a glucosamide-type silicone gemini surfactant.
  5. 5. The amphoteric surfactant according to claim 4, characterized in that, the sulfobetaine type double sub-organosilicon surface-active the agent comprises bis (trisiloxane) sulfobetaine.
  6. 6. The amphoteric surfactant of claim 1, wherein the nonionic emulsifier comprises polyoxyethylene sorbitan monooleate.
  7. 7. The amphoteric surfactant of claim 1, wherein the environmentally friendly organic scale inhibitor comprises polyaspartic acid.
  8. 8. The amphoteric surfactant of claim 1, wherein the macromolecular foam stabilizer comprises one or more of hydroxypropyl guar, xanthan gum, and partially hydrolyzed polyacrylamide.
  9. 9. The method for preparing the amphoteric surfactant according to any one of claims 1 to 8, comprising the steps of: Mixing alkylphenol ethoxylates, inorganic alkaline substances and an organic solvent for hydrolysis reaction to obtain a hydrolysis product; carboxylation reaction is carried out on the hydrolysate and chloroacetic acid to obtain a carboxymethylation intermediate; mixing the carboxymethylation intermediate, epichlorohydrin and sodium isethionate for etherification and sulfonation reaction to obtain the main body of the sulfonic acid-carboxylic acid type amphoteric surfactant; mixing the main body of the sulfonic acid-carboxylic acid type amphoteric surfactant, a gemini type organosilicon surfactant, a nonionic emulsifier, an environment-friendly organic scale inhibitor, a macromolecular foam stabilizer and water to obtain the amphoteric surfactant.
  10. 10. Use of the amphoteric surfactant according to any one of claims 1 to 8 or the amphoteric surfactant prepared by the preparation method according to claim 9 in the field of oil fields.

Description

Amphoteric surfactant and preparation method and application thereof Technical Field The invention relates to the technical field of oilfield chemistry, in particular to an amphoteric surfactant, a preparation method and application thereof. Background With the continuous increase of energy demand and continuous decrease of crude oil reserves, the development of low permeability reservoirs is more and more prominent. The low permeability oil reservoir is characterized by high initial yield and rapid decrease in later period due to poor physical properties of the reservoir, and is always characterized by ' no injection and ' no production ' in the development process, and the conventional production and injection increasing measures have poor effects. Chemical flooding technology is increasingly attracting attention in order to maximize the recoverable reserves of the oil field and maintain relatively high recovery rates. The surfactant flooding, polymer flooding, compound flooding and other technologies can reduce the oil-water interfacial tension, increase the capillary number, promote the crude oil to be desorbed from the rock and effectively disperse, and realize the effective driving of the residual oil, thereby improving the recovery ratio. However, existing surfactants still suffer from a number of disadvantages in the ultra-high mineralization (> 30,000 mg/L) and high calcium magnesium ion (> 2000 mg/L) environments. Firstly, the interfacial tension reducing capability and stability of the surfactant are insufficient, and the oil displacement requirement under a high-temperature (higher than 120 ℃) high-salt environment is difficult to meet, for example, the oil displacement agent in the related art comprises amphoteric hydrophobic association type polyacrylamide and fatty alcohol polyoxyethylene ether sulfonate surfactant, the oil displacement agent has insufficient temperature resistance and salt resistance, and the application requirement under an ultra-high mineralization environment is difficult to meet. Secondly, the existing surfactant lacks of the synergistic functions of scale prevention and foam stabilization, which is easy to cause formation blockage and reduction of oil displacement efficiency, such as foaming agent formed by at least one of weak cationic ampholytic surfactant, cationic surfactant, ampholytic surfactant and alcohol, has strong foamability, stability and profile control oil displacement capacity, but has the defects in the aspect of flow pattern control of foam fluid, and is difficult to realize optimal recovery efficiency in ultra-high mineralization environment. Disclosure of Invention In view of the above, the present invention aims to provide an amphoteric surfactant, and a preparation method and application thereof. The amphoteric surfactant provided by the invention not only can keep stable interfacial activity and chemical stability under the environment of ultrahigh mineralization degree and high calcium and magnesium ions, but also can effectively prevent formation scaling and blocking, and can also enhance foam stability, thereby improving oil displacement efficiency. In order to achieve the above object, the present invention provides the following technical solutions: the invention provides an ampholytic surfactant, which comprises the following components in percentage by mass: 3-8% of a main body of a sulfonic acid-carboxylic acid type amphoteric surfactant, 1-3% of a gemini type organic silicon surfactant, 2-5% of a nonionic emulsifier, 4-7% of an environment-friendly organic antiscaling agent, 1-2% of a macromolecular foam stabilizer and the balance of water; The sulfonic acid-carboxylic acid type amphoteric surfactant body is prepared by a method comprising the following steps: Mixing alkylphenol ethoxylates, inorganic alkaline substances and an organic solvent for hydrolysis reaction to obtain a hydrolysis product; carboxylation reaction is carried out on the hydrolysate and chloroacetic acid to obtain a carboxymethylation intermediate; mixing the carboxymethylation intermediate, epichlorohydrin and sodium isethionate for etherification and sulfonation reaction to obtain the main body of the sulfonic acid-carboxylic acid type amphoteric surfactant; the molecular weight of the macromolecular foam stabilizer is 10,000-3,000,000 g/mol. Preferably, the amphoteric surfactant comprises the following components in percentage by mass: Sulfonic acid-carboxylic acid type amphoteric surfactant main body 5%, gemini type organosilicon surfactant 2%, nonionic emulsifier 3%, environment-friendly organic antiscaling agent 5%, macromolecular foam stabilizer 1.5% and the balance of water. Preferably, the alkylphenol ethoxylates include nonylphenol ethoxylates. Preferably, the gemini silicone surfactant comprises one or more of a sulfobetaine-type gemini silicone surfactant, a quaternary ammonium salt-type gemini silicone surfactant, and a glucosamide-based silicone gemini