A fully acetylated polysaccharide derivative promoting agent, and a preparation method and application thereof
By preparing fully acetylated polysaccharide derivatives, a molecular structure with flexible linkers and a hydrophobic shell was constructed, which solved the problem of insufficient interfacial arrangement density and synergistic effect of multifunctional groups in polysaccharide-based surfactants, and achieved an efficient effect of reducing the minimum miscibility pressure of CO2 in oil fields.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-16
- Publication Date
- 2026-03-27
AI Technical Summary
Existing polysaccharide-based surfactants have shortcomings in terms of insufficient interfacial arrangement density and synergistic effects of multifunctional groups, making it difficult to achieve precise control in complex interfacial environments.
By using a method for preparing fully acetylated polysaccharide derivatives, alkyl polysaccharides are linked with glycidyl ethers to form a "polysaccharide-linker-polysaccharide" symmetrical topological structure, and then fully acetylated to construct a molecular structure with a flexible linker and a hydrophobic shell.
It enhances the ability of molecules to arrange themselves in an orderly manner at the interface, realizes molecular self-adaptive properties and carbon dioxide affinity, and significantly improves the effect of reducing the minimum miscibility pressure of CO2 in oil fields, achieving a demixing efficiency of 28.54%.
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Figure CN121342896B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of polysaccharide derivatives, and particularly relates to a fully acetylated polysaccharide derivative promoting agent, a preparation method and application thereof. BACKGROUND
[0002] In recent years, with the emphasis on the development and utilization of biomass resources, the demand for high-performance and environmentally friendly functional materials is increasing. As an important part of natural renewable resources, polysaccharide substances have attracted much attention due to their wide sources and good biocompatibility. The preparation of derivatives through chemical modification of natural polysaccharides has become a key research direction to expand their functional and application range. For example, traditional polysaccharide derivatives such as sodium alginate and chitosan mainly impart specific properties through modification of hydroxyl or amino groups, but their molecular structures are usually dependent on the inherent linear or network skeleton of natural polysaccharides. This inherent characteristic limits the precise regulation ability of polysaccharide derivatives in complex interfacial behavior, especially in harsh environments that require the synergistic regulation of multiple interfacial interactions.
[0003] Under this background, innovative design of molecular structure has become the core to break through the existing technical bottlenecks. Although the existing polysaccharide-based surfactants have improved surface activity to some extent through hydrophobic chain modification, their single-chain structure has inherent limitations in molecular conformation: on the one hand, the simple combination of a single hydrophobic chain and a hydrophilic group leads to insufficient interfacial arrangement density, which reduces the mechanical strength of the interfacial film; on the other hand, this one-dimensional linear structure is difficult to realize the synergistic effect of multifunctional groups, and there is a significant deficiency in interfacial stability and functional integration. SUMMARY
[0004] In order to overcome the above-mentioned problems in the prior art, the present application provides a fully acetylated polysaccharide derivative promoting agent, a preparation method and application thereof.
[0005] The technical scheme adopted by the present application to solve its technical problems is that a fully acetylated polysaccharide derivative promoting agent is formed by glycidyl ether connecting alkyl polyglycoside and full acetylation, and the structural general formula is as follows:
[0006]
[0007] wherein m is 1-2.5; n is 2-6; R1 is selected from any one of straight-chain or branched-chain alkyl with carbon atom number of 8-14.
[0008] A preparation method of a fully acetylated polysaccharide derivative promoting agent is used to prepare the fully acetylated polysaccharide derivative promoting agent as described above, and specifically includes the following steps:
[0009] Step 1, alkyl polyglycoside and inorganic strong base catalyst are placed in a reactor, stirred at 25℃ for 1h, then the system is warmed to 60℃, and the mixed glycidyl ether and isopropyl alcohol are slowly added to the reaction system under stirring, and the etherification reaction obtains polysaccharide derivatives;
[0010] Step 2, acetic anhydride and polysaccharide derivatives obtained in step 1 are placed in a reactor according to the molar ratio of (8.00-10.00):1.00, then an organic weak base catalyst, a water removal agent, and an acyl transfer accelerator are added, the reaction system is stirred at 0℃ for 1h under nitrogen atmosphere protection, then the temperature is raised to 60℃ to continue the esterification reaction, and finally the fully acetylated polysaccharide derivative is obtained.
[0011] The preparation method of the above-mentioned polysaccharide derivative promoter, the molar ratio of alkyl polyglycoside to glycidyl ether in step 1 is (2.00-2.50):1.00.
[0012] The preparation method of the above-mentioned polysaccharide derivative promoter, the amount of inorganic strong base catalyst in step 1 is 2.00%-2.50% of the mass of alkyl polyglycoside.
[0013] The preparation method of the above-mentioned polysaccharide derivative promoter, the amount of organic weak base catalyst in step 2 is 2.00%-2.50% of the mass of polysaccharide derivative.
[0014] The preparation method of the above-mentioned polysaccharide derivative promoter, the inorganic strong base is selected from any one or more of sodium hydroxide, potassium hydroxide, sodium hydride, calcium hydroxide, and anhydrous sodium carbonate; the organic weak base is selected from any one or more of pyridine, triethylamine, diisopropylethylamine, 2,6-lutidine, and N-methylmorpholine.
[0015] The preparation method of the above-mentioned polysaccharide derivative promoter, the alkyl polyglycoside is selected from any one or more of alkyl glycosides with 8-14 carbon atoms.
[0016] The preparation method of the above-mentioned polysaccharide derivative promoter, the water removal agent is selected from any one or more of silica gel, molecular sieves, activated carbon, and anhydrous sodium sulfate; the acyl transfer accelerator is selected from any one or more of 4-dimethylaminopyridine, 4-pyrrolidinopyridine, N-methylimidazole, and triazolium ionic liquid.
[0017] The application of a polysaccharide derivative promoter in reducing the minimum miscibility pressure of CO2 in offshore oilfields, using a polysaccharide derivative promoter as described above or prepared based on the above preparation method.
[0018] The application described above, characterized in that the concentration of the full acetylated polysaccharide derivative demulsifying promoter used for demulsification is 0.3wt%-1.5wt%.
[0019] The beneficial effects of the present application are that the present application provides a full acetylated polysaccharide derivative, which covalently connects two alkyl polysaccharide units through a glycidyl ether linking group, to construct a novel molecule with a "polysaccharide glycoside-linking group-polysaccharide glycoside" symmetric topological structure. The symmetry of this structure enhances the ordered arrangement ability of the molecule at the interface, the flexible linking group endows it with conformational self-adapting characteristics, and the hydrophobic shell formed by full acetylation modification exhibits excellent carbon dioxide affinity through specific interaction with CO2 molecules. Experiments show that the derivative exhibits excellent demulsification effect in the oil field crude oil-CO2 system, and it is found that the demulsification efficiency of 1.5wt% polysaccharide derivative is up to 28.54%, which shows important application value in the field of oil field carbon dioxide flooding. BRIEF DESCRIPTION OF DRAWINGS
[0020] Figure 1 is the nuclear magnetic resonance hydrogen spectrum analysis of the full acetylated polysaccharide derivative prepared in Example 2 of the present application;
[0021] Figure 2 is the nuclear magnetic resonance hydrogen spectrum analysis of the full acetylated polysaccharide derivative prepared in Example 3 of the present application;
[0022] Figure 3 is the nuclear magnetic resonance hydrogen spectrum analysis of the full acetylated polysaccharide derivative prepared in Example 4 of the present application;
[0023] Figure 4 is the nuclear magnetic resonance hydrogen spectrum analysis of the full acetylated polysaccharide derivative prepared in Example 5 of the present application;
[0024] Figure 5 is the Fourier infrared spectrum analysis of the full acetylated polysaccharide derivative prepared in Example 2-Example 5 of the present application;
[0025] Figure 6 is the effect diagram of the CO2 minimum miscibility pressure of the full acetylated polysaccharide derivative prepared in Example 2-Example 5 of the present application on a certain oil field. DETAILED DESCRIPTION
[0026] In order for those skilled in the art to better understand the technical solutions of the present application, the present application will be described in detail below in combination with the drawings and specific embodiments.
[0027] Example 1
[0028] The embodiment discloses a full-acetylated polysaccharide derivative promoting mixing agent, characterized by being formed by connecting an alkyl polyglycoside with glycidyl ether and full acetylation, and having a general structure as follows:
[0029]
[0030] wherein m is 1-2.5; n is 2-6; and R1 is selected from any one of straight-chain or branched-chain alkyl groups with 8-14 carbon atoms.
[0031] Embodiment 2
[0032] The embodiment provides a preparation method of a full-acetylated polysaccharide derivative, comprising the following steps.
[0033] S1. 32.00 g of APG0810 and 0.64 g of an inorganic strong base catalyst are placed in a three-necked flask, stirred for 1 hour under the condition of an oil bath at 25 DEG C, then the system is heated to 60 DEG C, 17.40 g of ethylene glycol diglycidyl ether and 5.00 g of isopropyl alcohol are uniformly mixed in a dropping funnel in advance, and slowly added to the reaction system under stirring, an etherification reaction is carried out, the reaction is tracked by infrared spectroscopy until the reaction is completed, and isopropyl alcohol is distilled out under reduced pressure after the reaction is completed, to obtain APG0810-EGDE.
[0034] S2. 25.00 g of APG0810-EGDE and 28.22 g of acetic anhydride are placed in a four-necked flask, then 0.50 g of an organic weak base is added as a catalyst, 5.00 g of a water-removing agent and 0.12 g of an acyl transfer accelerator are added, the reaction system is stirred at 0 DEG C for 1 hour under the protection of a nitrogen atmosphere, then heated to 60 DEG C to continue the esterification reaction, the esterification rate is monitored at intervals until the esterification rate remains unchanged, and a full-acetylated polysaccharide derivative is prepared. The nuclear magnetic resonance hydrogen spectrum analysis of the full-acetylated polysaccharide derivative is shown in Figure 1 .
[0035] Embodiment 3
[0036] The embodiment provides a preparation method of a full-acetylated polysaccharide derivative, comprising the following steps.
[0037] S1. 35.80 g of APG1214 and 0.72 g of an inorganic strong base catalyst are placed in a three-necked flask, stirred for 1 hour under the condition of an oil bath at 25 DEG C, then the system is heated to 60 DEG C, 17.40 g of ethylene glycol diglycidyl ether and 5.00 g of isopropyl alcohol are uniformly mixed in a dropping funnel in advance, and slowly added to the reaction system under stirring, an etherification reaction is carried out, the reaction is tracked by infrared spectroscopy until the reaction is completed, and isopropyl alcohol is distilled out under reduced pressure after the reaction is completed, to obtain APG1214-EGDE.
[0038] S2. Put 25.00 g of the APG1214-EGDE and 25.79 g of acetic anhydride into a four-necked flask, then add 0.50 g of an organic weak base as a catalyst, and add 5.00 g of a water-removing agent and 0.12 g of acyl transfer acceleration; under the protection of a nitrogen atmosphere, first stir the reaction system at 0°C for 1 hour, then warm it up to 60°C to continue the esterification reaction, monitor the esterification rate change at regular time intervals, and stop the reaction when the esterification rate remains unchanged, to prepare a fully acetylated polysaccharide derivative. The nuclear magnetic resonance hydrogen spectrum analysis of the fully acetylated polysaccharide derivative is shown in Figure 2 .
[0039] Example 4
[0040] The preparation method of a fully acetylated polysaccharide derivative provided in this example includes the following steps:
[0041] S1. Put 32.00 g of APG0810 and 0.60 g of an inorganic strong base catalyst into a three-necked flask, and stir at 25°C under oil bath conditions for 1 hour; then warm the system up to 60°C, and mix 21.80 g of diethylene glycol diglycidyl ether and 5.00 g of isopropyl alcohol in a dropping funnel, and slowly add them to the reaction system under stirring to perform etherification reaction, track the reaction by infrared spectrum until the reaction is completed, and then distill off the isopropyl alcohol under reduced pressure to obtain APG0810-DGDE.
[0042] S2. Put 25.00 g of the APG0810-DGDE and 26.72 g of acetic anhydride into a four-necked flask, then add 0.50 g of an organic weak base as a catalyst, and add 5.00 g of a water-removing agent and 0.12 g of acyl transfer acceleration; under the protection of a nitrogen atmosphere, first stir the reaction system at 0°C for 1 hour, then warm it up to 60°C to continue the esterification reaction, monitor the esterification rate change at regular time intervals, and stop the reaction when the esterification rate remains unchanged, to prepare a fully acetylated polysaccharide derivative. The nuclear magnetic resonance hydrogen spectrum analysis of the fully acetylated polysaccharide derivative is shown in Figure 3 .
[0043] Example 5
[0044] The preparation method of a fully acetylated polysaccharide derivative includes the following steps:
[0045] S1. 35.80 g of APG1214 and 0.72 g of inorganic strong base catalyst were placed in a three-necked flask and stirred at 25°C in an oil bath for 1 hour; then the system was warmed to 60°C, and 21.80 g of diethylene glycol diglycidyl ether and 5.00 g of isopropanol were mixed uniformly in a dropping funnel and slowly added to the reaction system under stirring to carry out etherification reaction. The reaction was tracked by infrared spectroscopy until the reaction was completed. After the reaction was completed, isopropanol was distilled off under reduced pressure to obtain APG1214-DGDE.
[0046] S2. 25.00 g of APG1214-DGDE and 24.57 g of acetic anhydride were placed in a four-necked flask, then 0.50 g of organic weak base was added as a catalyst, and 5.00 g of water scavenger and 0.12 g of acyl transfer accelerator were added. Under the protection of nitrogen atmosphere, the reaction system was first stirred at 0°C for 1 hour, and then warmed to 60°C to continue the esterification reaction. The esterification rate was monitored at regular time intervals until the esterification rate remained unchanged, and a fully acetylated polysaccharide derivative was prepared. The nuclear magnetic resonance hydrogen spectrum of the fully acetylated polysaccharide derivative is shown in Figure 4 .
[0047] The Fourier infrared spectrum of the polysaccharide derivative prepared by the preparation method of Example 2-Example 5 was analyzed, and the analysis results are shown in Figure 5 .
[0048] The polysaccharide derivative prepared in Example 2-Example 5 was tested for reducing the minimum miscibility pressure performance: a crude oil sample from a certain oilfield in China was selected for evaluation, and the interfacial tension disappearance method (VIT) was used. The oil phase was injected into a high-temperature and high-pressure visual cell and heated to 70°C. A capillary tube was used to suspend a CO2 bubble in the oil phase. The pressure was gradually increased, and the bubble shape was recorded synchronously and the interfacial tension was calculated. When the interfacial tension approached zero and the bubble outline was about to dissipate, the pressure was the minimum miscibility pressure. The minimum miscibility pressure between pure CO2 and crude oil was measured to be 21.90 MPa. The minimum miscibility pressure of "CO2+1.5wt% fully acetylated sugar derivative" was measured by the same method. The minimum miscibility pressures of Example 2, Example 3, Example 4, and Example 5 were 17.44 MPa, 16.11 MPa, 17.23 MPa, and 15.65 MPa, respectively. Among them, the demulsification effect of Example 5 was the best, with a demulsification efficiency of up to 28.54%. The effect of the fully acetylated polysaccharide derivative on the CO2 minimum miscibility pressure of a certain oilfield is shown in Figure 6 .
[0049] The full acetylated polysaccharide derivative provided by the application realizes structural innovation through precise molecular regulation. The structure takes two alkyl polysaccharide glycosides as basic units, and realizes covalent connection through a flexible linker constructed by a glycidyl ether, forming a unique "polysaccharide glycoside-linker-polysaccharide glycoside" symmetric topological architecture. On this basis, full acetylation modification is carried out to form a regular hydrophobic protective layer on the periphery of the molecule, successfully constructing a stable structure with a clear hydrophilic region and a hydrophobic shell.
[0050] This innovative molecular design brings three key structural advantages: first, the symmetric topological configuration significantly improves the ordered arrangement ability of the molecule at the interface; second, the flexible linker gives the molecule appropriate conformational freedom, enabling it to adapt to the multi-phase interface environment; finally, the synergistic effect of acetylation modification and alkyl chains realizes the precise balance of hydrophilic-hydrophobic properties. It is particularly noteworthy that the specific interaction between the peripheral dense acetyl groups in this structure and supercritical carbon dioxide molecules makes it exhibit excellent carbon dioxide affinity.
[0051] Experimental verification shows that the polysaccharide derivative exhibits excellent interfacial activity in the test of an oilfield crude oil-carbon dioxide system, and it is found that 1.5wt% full acetylated sugar derivative has a maximum of 28.54% of the demulsification efficiency. The unique performance obtained by this structural innovation makes it exhibit important application value in the field of oil and gas development such as oilfield carbon dioxide flooding.
[0052] The above examples are only exemplary embodiments of the application and are not intended to limit the application. Those skilled in the art can make various modifications or equivalent replacements to the application within the spirit and protection scope of the application, and such modifications or equivalent replacements shall also be considered to fall within the protection scope of the application.
Claims
1. A peracetylated polysaccharide derivative facilitating agent, characterized by comprising: A glycidyl ether is connected to an alkyl polyglycoside and fully acetylated to form a structure general formula: Wherein, m is 1-2.5; n is 2-6; R1 is selected from any one of the straight chain or branched chain alkyl with carbon number of 8-14.
2. A method for producing a total acetylated polysaccharide derivative dispersion aid, characterized by, The application relates to a preparation method of a full-acetylated polysaccharide derivative promoting agent. Step 1: alkyl polyglycoside and inorganic strong base catalyst are placed in a reactor, stirred at 25 DEG C for 1h, then the system is heated to 60 DEG C, and mixed glycidyl ether and isopropyl alcohol are slowly added dropwise into the reaction system under stirring, and etherification is carried out to obtain a polysaccharide derivative; Step 2: acetic anhydride and the polysaccharide derivative obtained in step 1 are placed in a reactor according to a molar ratio of (8.00-10.00):1.00, then an organic weak base catalyst, a water-removing agent and an acyl transfer accelerator are added, the reaction system is stirred at 0 DEG C for 1h under nitrogen atmosphere protection, then the system is heated to 60 DEG C to continue esterification, and finally a full-acetylated polysaccharide derivative is obtained; The inorganic strong base is selected from any one or more of sodium hydroxide, potassium hydroxide, sodium hydride, calcium hydroxide and anhydrous sodium carbonate; and the organic weak base is selected from any one or more of pyridine, triethylamine, diisopropyl ethylamine, 2,6-dimethyl pyridine and N-methyl morpholine. The alkyl polyglycoside is selected from any one or more of alkyl glycosides with carbon number of 8-14. The water-removing agent is selected from any one or more of silica gel, molecular sieve, activated carbon and anhydrous sodium sulfate; and the acyl transfer accelerator is selected from any one or more of 4-dimethylamino pyridine, 4-pyrrolidinyl pyridine, N-methyl imidazole and triazole ionic liquid.
3. The method of claim 2, wherein the method is characterized by the steps of: The molar ratio of the alkyl polyglycoside to the glycidyl ether in step 1 is (2.00-2.50):1.
00.
4. The method of claim 2, wherein the method is characterized by the steps of: The amount of the inorganic strong base catalyst in step 1 is 2.00%-2.50% of the mass of the alkyl polyglycoside.
5. The method for preparing a fully acetylated polysaccharide derivative blending agent according to claim 2, characterized in that, The amount of the organic weak base catalyst in step 2 is 2.00%-2.50% of the mass of the polysaccharide derivative.
6. Use of a peracetylated polysaccharide derivative miscibility enhancer to reduce the minimum miscibility pressure of CO2 in offshore oil fields, characterized in that, The full-acetylated polysaccharide derivative promoting agent is used for de-mixing at a concentration of 0.3wt%-1.5wt%.
7. Use according to claim 6, characterized in that,