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CN-121974964-A - High-salt-tolerance alkyl glycoside modified gemini surfactant and preparation method thereof

CN121974964ACN 121974964 ACN121974964 ACN 121974964ACN-121974964-A

Abstract

The invention belongs to the technical field of zwitterionic surfactants, and discloses a high-salt-tolerance alkyl glycoside modified gemini surfactant and a preparation method thereof, wherein the molecular structural formula of the surfactant is as follows: Wherein R is a straight-chain alkyl group with a carbon number of m, m is more than or equal to 8 and less than or equal to 14, m is an integer, n is an average polymerization degree, and n=1.1-2. The surfactant disclosed by the invention not only inherits the green characteristic of APG, but also has excellent salt tolerance and emulsification regulation and control capability, and can effectively reduce the oil-water interfacial tension and change the rock wettability in a hypersalinity environment, so that an innovative chemical solution is provided for improving the recovery ratio of the difficult-to-recover oil reservoir.

Inventors

  • WU YA
  • LI ZHENHUA
  • MU XIN
  • Shang Xiening
  • LI YONGFEI
  • CHEN GANG

Assignees

  • 西安石油大学

Dates

Publication Date
20260505
Application Date
20260316

Claims (9)

  1. 1. The high salt-tolerant alkyl glycoside modified gemini surfactant is characterized by having a molecular structural formula as follows: Wherein R is a straight-chain alkyl group with a carbon number of m, m is more than or equal to 8 and less than or equal to 14, m is an integer, n is an average polymerization degree, and n=1.1-2.
  2. 2. The preparation method of the high salt-tolerant alkyl glycoside modified gemini surfactant is characterized by comprising the following steps of: S1, adding alkyl glycoside into a mixed solvent of pyridine and tetrahydrofuran for dissolution, slowly dropwise adding chloroacetyl chloride under ice bath condition, and reacting under mechanical stirring; S2, adding the alkyl glycoside chloroacetate intermediate into tetrahydrofuran for dissolution, using triethylamine as an acid binding agent, dropwise adding N, N' -dimethyl ethylenediamine under the ice bath condition, reacting at constant temperature, filtering out salt after the reaction is finished, and performing vacuum distillation to obtain the alkyl glycoside di-tertiary amine intermediate. S3, dissolving the alkyl glycoside di-tertiary amine intermediate in an isopropanol-water mixed solvent, adding potassium carbonate to adjust the pH of the system to 8-10, adding 3-chloro-2-hydroxy propane sodium sulfonate, condensing and refluxing at 80-85 ℃, distilling under reduced pressure after the reaction is finished, collecting reflux liquid, and desalting by adopting ethanol to obtain the target product alkyl glycoside modified disulfonic acid betaine type gemini surfactant.
  3. 3. The method for preparing the high salt-tolerant alkyl glycoside modified gemini surfactant according to claim 2, wherein the molar ratio of the alkyl glycoside to the chloroacetyl chloride is 1 (1.0-1.2).
  4. 4. The method for preparing the high salt-tolerant alkyl glycoside modified gemini surfactant according to claim 2, wherein the molar ratio of the alkyl glycoside chloroacetate intermediate to the N, N' -dimethylethylenediamine is 1 (0.5-0.7).
  5. 5. The method for preparing a high salt tolerance alkyl glycoside modified gemini surfactant according to claim 2, wherein the pyridine is 2.5-5 equivalents of alkyl glycoside.
  6. 6. The method for preparing the high salt-tolerant alkyl glycoside modified gemini surfactant according to claim 2, wherein the reaction temperature under the ice bath condition is 0-10 ℃.
  7. 7. The method for preparing a high salt tolerance alkyl glycoside modified gemini surfactant according to claim 2, wherein the molar ratio of the alkyl glycoside di-tertiary amine intermediate to the sodium 3-chloro-2-hydroxy propane sulfonate is 1 (2.0-2.4).
  8. 8. The method for preparing a high salt-tolerant alkyl glycoside modified gemini surfactant according to claim 2, wherein the alkyl glycoside is at least one of C8-C14 alkyl glycosides.
  9. 9. Use of the high salt tolerance alkyl glycoside modified gemini surfactant of claim 1 or the high salt tolerance alkyl glycoside modified gemini surfactant prepared by the preparation method of any one of claims 2 to 8 in oilfield exploitation.

Description

High-salt-tolerance alkyl glycoside modified gemini surfactant and preparation method thereof Technical Field The invention belongs to the technical field of amphoteric surfactants, and particularly relates to a high-salt-tolerance alkyl glycoside modified gemini surfactant and a preparation method thereof. Background Alkyl glycoside (APG) is widely used in the fields of daily chemicals, textiles, etc. as a green surfactant synthesized from natural fatty alcohol and glucose due to its low toxicity, easy degradation and excellent surface activity, foam and detergency. However, its use also suffers from two major inherent drawbacks, namely reduced water solubility with alkyl chain growth and significant reduction in foam performance in hard water environments. In order to break through the limitations, the application of the APG in a severe environment is expanded, and the molecular modification of the APG becomes a key research direction. In particular in the field of oilfield chemistry, as exploitation is shifted to a high-mineralization and low-permeability unconventional oil reservoir, the traditional surfactant is extremely easy to form a precipitate with Ca 2+、Mg2+ plasma in formation water to fail, and development of novel salt-tolerant chemicals is urgently needed. Disclosure of Invention The invention provides a high salt-tolerant alkyl glycoside modified gemini surfactant and a preparation method thereof, which aim to solve the development problems of unconventional oil reservoirs such as hypersalinity and the like. Multiple salt-tolerant and functional groups are introduced into the APG molecule through the steps of acetylchlorination, polyamine chain extension, sultone quaternization and the like. The modified product not only inherits the green characteristic of APG, but also has excellent salt tolerance and emulsification regulation and control capability, and can effectively reduce the oil-water interfacial tension and change the rock wettability in a hypersalinity environment, thereby providing an innovative chemical solution for improving the recovery ratio of the difficult-to-recover oil reservoir. In order to achieve the above object, in a first aspect, the present invention provides a high salt tolerance alkyl glycoside modified gemini surfactant, which is characterized in that the molecular structural formula is: Wherein R is a straight-chain alkyl group with a carbon number of m, m is more than or equal to 8 and less than or equal to 14, m is an integer, n is an average polymerization degree, and n=1.1-2. According to a second aspect of the invention, the invention also provides a preparation method of the high salt-tolerant alkyl glycoside modified gemini surfactant, which comprises the following steps: S1, placing alkyl glycoside into an oven, evaporating to remove water, transferring into a three-neck flask, adding a mixed solvent of pyridine and tetrahydrofuran, mechanically stirring and dissolving, slowly dropwise adding chloroacetyl chloride under an ice bath condition, mechanically stirring and reacting for 3-4h, filtering to remove generated pyridine hydrochloride after the reaction is finished, and distilling under a vacuum condition to remove residual pyridine and excessive chloroacetyl chloride to obtain an alkyl glycoside chloroacetate intermediate. S2, adding the intermediate obtained in the step S1 into a three-neck flask, adding tetrahydrofuran for dissolution, taking triethylamine as an acid binding agent, dropwise adding N, N '-dimethyl ethylenediamine under the ice bath condition, reacting at constant temperature for 6-8 hours, filtering for desalting after the reaction is finished, and removing residual triethylamine, N' -dimethyl ethylenediamine and a solvent by vacuum distillation to obtain the alkyl glycoside di-tertiary amine intermediate. S3, dissolving the intermediate prepared in the step S2 in an isopropanol-water mixed solvent (preferably with the volume ratio of 1:1-1:2), adding potassium carbonate to adjust the pH of the system to 8-10, adding 3-chloro-2-hydroxypropyl sodium sulfonate in batches, performing condensation reflux reaction for 8-12 hours at 80-85 ℃, distilling under reduced pressure to remove water after the reaction is finished, collecting reflux liquid, and performing desalination treatment by adopting ethanol to obtain the target product alkyl glycoside modified disulfonic acid betaine type gemini surfactant. As a further preferable technical scheme of the invention, the molar ratio of the alkyl glycoside to the chloroacetyl chloride in the step S1 is 1 (1.0-1.2), and the molar ratio of the alkyl glycoside chloroacetate intermediate to the N, N' -dimethylethylenediamine in the step S2 is 1 (0.5-0.7). In the step 1), pyridine has the functions of both solvent and acid-binding agent, the addition amount of pyridine is maintained in excess, preferably 2.5-5 equivalents of alkyl glycoside, so as to ensure that byproduct HCl generated by the react