Green and environment-friendly polyether demulsifier and preparation method thereof

Abstract

The invention relates to the technical field of demulsifiers, in particular to a green and environment-friendly polyether demulsifier and a preparation method thereof, and the green and environment-friendly polyether demulsifier is prepared from the following raw materials in parts by weight: 5-15 parts of a biological initiator, 60-80 parts of epoxypropane, 20-40 parts of ethylene oxide, 0.3-0.8 part of a catalyst and 100-150 parts of deionized water. Hydrophobized chitosan oligosaccharide in the used biological initiator can rapidly destroy an oil-water interfacial film, cellulose powder promotes droplet coalescence, the hydrophobic chitosan oligosaccharide and the cellulose powder have a synergistic effect, the demulsifier has the excellent performance of being high in demulsification speed and dehydration rate, meanwhile, the raw materials are derived from renewable biomass, and the environment-friendly effect is achieved. A supercritical carbon dioxide fluid technology and enzymatic degradation are adopted in the preparation process, and the product is low in environmental toxicity and good in biodegradability.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of demulsifiers, in particular to a green and environmentally friendly polyether demulsifier and a preparation method thereof. BACKGROUND

[0002] A demulsifier is a chemical additive used to destroy the stability of emulsions and promote oil-water separation. It is widely used in oil exploration, wastewater treatment, food processing and other fields. Traditional demulsifiers are mostly synthetic surfactants such as alkylphenol polyoxyethylene ether (APEO) and sulfonate. Among them, polyether demulsifiers have received widespread attention due to their adjustable structure and stable performance.

[0003] However, existing polyether demulsifiers still have problems such as low demulsification efficiency, poor biodegradability, and high environmental toxicity. Therefore, the present application provides a green and environmentally friendly polyether demulsifier and a preparation method thereof. SUMMARY

[0004] The present application aims to provide a green and environmentally friendly polyether demulsifier and a preparation method thereof. The green and environmentally friendly polyether demulsifier prepared by the present application not only has excellent demulsification performance, but also has good biodegradability and environmental compatibility, which meets the development direction of green chemistry.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical solutions: In a first aspect, the present application provides a green and environmentally friendly polyether demulsifier, comprising the following raw materials by weight: 5-15 parts of a biological initiator, 60-80 parts of propylene oxide, 20-40 parts of ethylene oxide, 0.3-0.8 parts of a catalyst, and 100-150 parts of deionized water.

[0006] The preparation of the biological initiator comprises the following steps: S1: Mix chitosan oligosaccharide powder and long-chain glycidyl ether at a mass ratio of 1: (0.2-0.5), place them in a supercritical carbon dioxide reaction kettle, and introduce carbon dioxide. The reaction kettle pressure is 15-25 MPa, and the reaction is carried out at 50-70℃ for 2-4h to obtain hydrophobic chitosan oligosaccharide; S2: Keep the supercritical state, add cellulose powder to the reaction kettle, and stir for 1-2h. After the reaction is completed, the pressure is released, the carbon dioxide gas is recovered, and the product is taken out and crushed to obtain the biological initiator.

[0007] Further, the preparation method of the chitosan oligosaccharide powder comprises the following steps: mixing chitosan and an acetic acid solution with a concentration of 2% according to a mass ratio of 1:(19-32) to obtain an acetic acid solution of chitosan oligosaccharide powder, adding immobilized chitosanase, and performing enzymolysis under the conditions of 45-55 DEG C and pH=5.0-5.5 for 6-10 h; after the enzymolysis, centrifugal separation is performed, the supernatant is taken, the pH is adjusted to 7.0-8.0 by using a sodium hydroxide solution, filtration is performed, the precipitate is obtained, vacuum drying is performed at 50-60 DEG C, and grinding is performed to obtain the chitosan oligosaccharide powder; and the mass of the immobilized chitosanase is 1%-2% of the mass of the chitosan.

[0008] Further, the preparation method of the cellulose powder comprises the following steps: S1: dispersing nanocellulose in deionized water to prepare a first suspension with a mass fraction of 1-3%, and adding an ionic liquid monomer 1-aminomethyl-3-methyl imidazole bromide into deionized water to prepare a second solution with a mass fraction of 5-10%; S2: under stirring, the second solution is added dropwise into the first suspension, a dilute acetic acid is used to adjust the pH value to 4.5-5.5 to obtain a premix, wherein the mass ratio of the ionic liquid monomer to the nanocellulose is (0.5-1.5):1; S3: carbodiimide hydrochloride is added into the premix, and reaction is performed at 50-60 DEG C for 12-24 h; after the reaction is completed, dialysis treatment is performed for 3-5 days; after the dialysis is completed, spray drying is performed to obtain the cellulose powder; and the mass of the carbodiimide hydrochloride is 10-20% of the mass of the ionic liquid monomer.

[0009] Further, the long-chain glycidyl ether is at least one of glycidyl dodecyl ether and glycidyl hexadecyl ether.

[0010] Further, the mass ratio of the hydrophobic chitosan oligosaccharide to the cellulose powder in the biological initiator is 100:(8-12).

[0011] Further, the catalyst is a double-metal cyanide complex catalyst.

[0012] In a second aspect, the present application provides a preparation method of a green and environmentally-friendly polyether demulsifier, comprising the following steps: S1: under nitrogen protection, a biological initiator, a catalyst and deionized water are added into a high-pressure reaction kettle, stirring reaction is performed at a rotating speed of 200-400 rpm, and heating is performed to 100-120 DEG C to obtain a reaction product; S2: after the reactants are vacuum dehydrated for 0.5-1h, propylene oxide is added, and the reaction is carried out at a pressure of 0.2-0.4MPa and a temperature of 115-125℃ for 2-3h, and ethylene oxide is added, and the reaction is continued under the same conditions for 2-3h, after the reaction is completed, the temperature is cooled to 60-70℃, and the product is discharged, to obtain the green and environmentally-friendly polyether demulsifier.

[0013] Compared with the prior art, the application has the following beneficial effects: 1、The bio-initiator used in the preparation of the green and environmentally-friendly polyether demulsifier is composed of hydrophobic chitosan oligosaccharide and cellulose powder, has high interfacial activity, and the hydrophobic chitosan oligosaccharide as a natural surfactant can quickly adsorb and destroy the oil-water interface film, and the rigid structure of the nanocellulose in the cellulose powder can effectively promote the coalescence of emulsion droplets, and the two have a synergistic effect, thereby greatly improving the demulsification speed and dehydration rate, and the application is especially suitable for treating stubborn oil-water emulsion.

[0014] 2、The application discards the non-environmentally-friendly substances such as alkyl phenol formaldehyde resin and polyol initiator commonly used in traditional demulsifiers, and the raw materials chitosan oligosaccharide and cellulose powder of the bio-initiator are derived from renewable biological substances such as animal shells and plant cellulose, have good biodegradability, in the preparation process, supercritical carbon dioxide fluid technology is used to replace organic solvents, and enzyme degradation is used to replace strong acid hydrolysis, the whole process conforms to the principle of green chemistry, and the final product has low environmental toxicity and good biodegradability. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 A flowchart of the green and environmentally-friendly polyether demulsifier is provided. DETAILED DESCRIPTION

[0016] The technical solutions in the embodiments of the application will be clearly and completely described below with reference to the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of the application.

[0017] In order to enable those skilled in the art to better understand the application scheme, the technical solutions in the embodiments of the application will be clearly and completely described below.

[0018] Embodiment 1:

[0019] Preparation of chitosan oligosaccharide powder: Chitosan is mixed with acetic acid solution with a concentration of 2% at a mass ratio of 1:19 to obtain an acetic acid solution of chitooligosaccharide powder, and immobilized chitosanase is added, and enzymolysis is carried out at 45℃ and pH=5.0 for 6h. After enzymolysis, centrifugation is performed, the supernatant is taken, and the pH is adjusted to 7.0 with sodium hydroxide solution. Filtration is performed, the precipitate is vacuum dried at 50℃, and grinding is performed to obtain chitooligosaccharide powder. The mass of the immobilized chitosanase is 1% of the mass of chitosan.

[0020] Preparation of cellulose powder: S1: Nanocellulose is dispersed in deionized water to prepare a first suspension with a mass fraction of 1%, and ultrasonic treatment is performed for 25min. Ionic liquid monomer 1-aminethyl-3-methyl imidazole bromide is dissolved in deionized water to prepare a second solution with a mass fraction of 5%; S2: The second solution is added dropwise to the first suspension under stirring, and dilute acetic acid is used to adjust the pH to 4.5 to obtain a premix. The mass ratio of the ionic liquid monomer to the nanocellulose is 0.5:1. S3: Carbodiimide hydrochloride is added to the premix, and reaction is performed at 50℃ for 12h. After reaction, dialysis is performed for 3 days, and spray drying is performed to obtain cellulose powder. The mass of the carbodiimide hydrochloride is 10% of the mass of the ionic liquid monomer.

[0021] Preparation of biological initiator: S1: Chitooligosaccharide powder is mixed with glycidyl hexadecyl ether at a mass ratio of 1:0.2, and is placed in a supercritical carbon dioxide reaction kettle. Carbon dioxide is introduced, and the pressure is controlled at 15MPa. Reaction is performed at 50℃ for 2h to obtain hydrophobized chitooligosaccharide. S2: The cellulose powder is added to the reaction kettle while maintaining the supercritical state, and stirring reaction is performed for 1h. After reaction, the pressure is released, and carbon dioxide is recovered to obtain a crude material. The crude material is taken out and crushed to obtain the biological initiator. The mass ratio of the hydrophobized chitooligosaccharide to the cellulose powder is 100:8.

[0022] Preparation of raw materials: 5 parts of biological initiator, 60 parts of propylene oxide, 20 parts of ethylene oxide, 0.3 parts of catalyst, and 100 parts of deionized water.

[0023] Preparation of green and environmentally friendly polyether demulsifier: S1: The biological initiator, double metal cyanide complex catalyst, and deionized water are added to a reaction kettle under nitrogen protection, and stirring is performed at a speed of 200rpm. Heating is performed to 100℃ to obtain a reactant. S2: After vacuum dehydration of the reactant for 0.5h, propylene oxide is added, and reaction is performed at a pressure of 0.2MPa and a temperature of 115℃ for 2h. Ethylene oxide is further added, and reaction is continued under the same conditions for 2h. After reaction, the temperature is cooled to 60℃, and the material is discharged to obtain the green and environmentally friendly polyether demulsifier.

[0024] Example 2:

[0025] Preparation of chitooligosaccharide powder: Chitosan was mixed with acetic acid solution with a concentration of 2% at a mass ratio of 1:25 to obtain an acetic acid solution of chitooligosaccharide powder, and immobilized chitosanase was added. Enzymatic hydrolysis was carried out at 50°C and pH 5.25 for 8h. After enzymatic hydrolysis, centrifugation was performed, the supernatant was taken, and the pH was adjusted to 7.5 with sodium hydroxide solution. Filtration was performed, and the precipitate was vacuum dried at 55°C. Grinding was performed to obtain chitooligosaccharide powder. The mass of the immobilized chitosanase was 1.5% of the mass of chitosan.

[0026] Preparation of cellulose powder: S1: Nanocellulose was dispersed in deionized water to prepare a first suspension with a mass fraction of 2%, and ultrasonic treatment was performed for 30min. Ionic liquid monomer 1-aminethyl-3-methyl imidazole bromide was dissolved in deionized water to prepare a second solution with a mass fraction of 8%; S2: The second solution was added dropwise to the first suspension under stirring, and the pH was adjusted to 5.0 with dilute acetic acid to obtain a premix. The mass ratio of the ionic liquid monomer to the nanocellulose was 1:1. S3: Carbodiimide hydrochloride was added to the premix, and reaction was carried out at 55°C for 18h. After the reaction was completed, dialysis was performed for 4 days, and spray drying was performed to obtain cellulose powder. The mass of the carbodiimide hydrochloride was 15% of the mass of the ionic liquid monomer.

[0027] Preparation of biological initiator: S1: Chitooligosaccharide powder was mixed with glycidyl hexadecyl ether at a mass ratio of 1:0.3, and the mixture was placed in a supercritical carbon dioxide reactor. Carbon dioxide was introduced, and the pressure was controlled at 20MPa. Reaction was carried out at 60°C for 3h to obtain hydrophobized chitooligosaccharide. S2: The cellulose powder was added to the reactor while maintaining the supercritical state, and stirring reaction was carried out for 1.5h. After the reaction was completed, the pressure was released, and carbon dioxide was recovered. The product was taken out and crushed to obtain the biological initiator. The mass ratio of the hydrophobized chitooligosaccharide to the cellulose powder was 100:10.

[0028] Preparation of raw materials: 10 parts of biological initiator, 70 parts of propylene oxide, 30 parts of ethylene oxide, 0.6 parts of catalyst, and 125 parts of deionized water.

[0029] Preparation of green and environmentally friendly polyether demulsifier: S1: The biological initiator, double metal cyanide complex catalyst, and deionized water were added to the reactor under nitrogen protection. Stirring was carried out at a speed of 300rpm, and heating was carried out to 110°C to obtain the reactant. S2: After the reactants were dehydrated under vacuum for 1 h, propylene oxide was added, and the reaction was carried out at a pressure of 0.3 MPa and a temperature of 120℃ for 2.5 h, then ethylene oxide was added, and the reaction was continued under the same conditions for 2.5 h. After the reaction was completed, the product was discharged after cooling to 65℃, and a green and environmentally friendly polyether demulsifier was obtained.

[0030] Example 3:

[0031] Preparation of chitooligosaccharide powder: Chitosan was mixed with an acetic acid solution with a concentration of 2% at a mass ratio of 1:32 to obtain an acetic acid solution of chitooligosaccharide powder, and immobilized chitosanase was added. The enzyme was hydrolyzed at 55℃ and pH 5.5 for 10 h. After hydrolysis, the supernatant was obtained by centrifugation, the pH was adjusted to 8.0 with sodium hydroxide solution, and the precipitate was filtered and dried at 60℃ under vacuum. The chitooligosaccharide powder was obtained by grinding. The mass of the immobilized chitosanase was 2% of the mass of the chitosan.

[0032] Preparation of cellulose powder: S1: Nanocellulose was dispersed in deionized water to prepare a first suspension with a mass fraction of 3%, and the ionic liquid monomer 1-aminomethyl-3-methyl imidazole bromide was dissolved in deionized water to prepare a second solution with a mass fraction of 10%; S2: The second solution was added dropwise to the first suspension under stirring, and the pH was adjusted to 5.5 with dilute acetic acid to obtain a premix. The mass ratio of the ionic liquid monomer to the nanocellulose was 1.5:1; S3: Carbonic diimide hydrochloride was added to the premix, and the reaction was carried out at 60℃ for 24 h. After the reaction was completed, the product was dialyzed for 5 days and spray dried to obtain cellulose powder. The mass of the carbonic diimide hydrochloride was 20% of the mass of the ionic liquid monomer.

[0033] Preparation of biological initiator: S1: Chitooligosaccharide powder was mixed with glycidyl hexadecyl ether at a mass ratio of 1:0.5 and placed in a supercritical carbon dioxide reactor. Carbon dioxide was introduced, and the pressure was controlled at 25 MPa at 70℃ for 4 h to obtain hydrophobic chitooligosaccharide; S2: The cellulose powder was added to the reactor under supercritical conditions, and the reaction was carried out under stirring for 2 h. After the reaction was completed, the pressure was released, and the carbon dioxide was recovered to obtain a crude material. The crude material was ground to obtain the biological initiator. The mass ratio of the hydrophobic chitooligosaccharide to the cellulose crude material was 100:12.

[0034] Preparation of green and environmentally friendly polyether demulsifier:

[0035] Preparation of green and environmentally friendly polyether demulsifier: S1: Under the protection of nitrogen, the biological initiator, double metal cyanide complex catalyst, and deionized water were added to a reaction kettle, stirred at a speed of 400 rpm, and heated to 120°C to obtain a reactant; S2: After vacuum dehydration of the reactant for 1 h, propylene oxide was added, and the reaction was carried out at a pressure of 0.4 MPa and a temperature of 125°C for 3 h. Then, ethylene oxide was added, and the reaction was continued under the same conditions for 3 h. After the reaction was completed, the temperature was cooled to 70°C, and the product was discharged. Thus, a green and environmentally friendly polyether demulsifier was obtained.

[0036] Comparative Example 1: The green and environmentally friendly polyether demulsifier provided by the present comparative example and its preparation method are substantially the same as those of Example 1, with the main difference being that no hydrophobic chitinous oligosaccharide is added, and only cellulose powder is used as the initiator.

[0037] Comparative Example 2: The green and environmentally friendly polyether demulsifier provided by the present comparative example and its preparation method are substantially the same as those of Example 1, with the main difference being that no cellulose powder is added, and only hydrophobic chitinous oligosaccharide is used as the initiator.

[0038] Comparative Example 3: The green and environmentally friendly polyether demulsifier provided by the present comparative example and its preparation method are substantially the same as those of Example 1, with the main difference being that propylene glycol is used instead of the biological initiator.

[0039] Comparative Example 4: The green and environmentally friendly polyether demulsifier provided by the present comparative example and its preparation method are substantially the same as those of Example 1, with the main difference being that the initiator is synthesized using N, N-dimethylformamide solvent under non-supercritical conditions.

[0040] Performance Test: The green and environmentally friendly polyether demulsifiers prepared in Example 1, Example 2, Example 3, Comparative Example 1, Comparative Example 2, Comparative Example 3, and Comparative Example 4 were subjected to performance testing, and the test data are recorded in the following table: Sample Dehydration rate (%) Demulsification time (min) Biodegradation rate (%) Example 1 96 8 89 Example 2 97 7 90 Example 3 98 8 91 Comparative Example 1 78 20 82 Comparative Example 2 80 18 85 Comparative Example 3 70 25 45 Comparative Example 4 75 22 70 In the performance test, the dehydration rate and demulsification speed test: the bottle test method was used to simulate the oilfield working conditions under constant temperature conditions by static separation, and the dehydration rate and oil-water interface clear time were used to evaluate the demulsification efficiency and speed. The biodegradability test: according to the GB / T21856-2008 standard, the carbon dioxide production test was used to determine the amount of carbon dioxide produced by the decomposition of the sample as the sole carbon source by microorganisms, to evaluate the final biodegradation ability within 28 days.

[0041] As can be seen from the data in the table, without the addition of hydrophobized chitinous oligosaccharide, the demulsification process can only rely on the physical coalescence of cellulose powder, which is far less efficient than the synergistic demulsification mechanism of chemical and physical methods, resulting in a longer demulsification time and insufficient dehydration rate. Although the biodegradability is still good, this is mainly due to the biocompatibility of cellulose powder itself. As a high-efficiency biosurfactant, the long-chain alkyl group in the molecular structure of hydrophobized chitinous oligosaccharide enables it to quickly migrate and embed into the oil-water interface layer, reducing the interfacial tension and ultimately tearing the interfacial film.

[0042] As can be seen from the data in the table, without the addition of hydrophobized chitinous oligosaccharide, the demulsification process can only rely on the physical coalescence of cellulose powder, which is far less efficient than the synergistic demulsification mechanism of chemical and physical methods, resulting in a longer demulsification time and insufficient dehydration rate. Although the biodegradability is still good, this is mainly due to the biocompatibility of cellulose powder itself. As a high-efficiency biosurfactant, the long-chain alkyl group in the molecular structure of hydrophobized chitinous oligosaccharide enables it to quickly migrate and embed into the oil-water interface layer, reducing the interfacial tension and ultimately tearing the interfacial film.

[0043] As can be seen from the data in the table, without the addition of hydrophobized chitinous oligosaccharide, the demulsification process can only rely on the physical coalescence of cellulose powder, which is far less efficient than the synergistic demulsification mechanism of chemical and physical methods, resulting in a longer demulsification time and insufficient dehydration rate. Although the biodegradability is still good, this is mainly due to the biocompatibility of cellulose powder itself. As a high-efficiency biosurfactant, the long-chain alkyl group in the molecular structure of hydrophobized chitinous oligosaccharide enables it to quickly migrate and embed into the oil-water interface layer, reducing the interfacial tension and ultimately tearing the interfacial film.

[0044] As can be seen from the data in the table, without the addition of hydrophobized chitinous oligosaccharide, the demulsification process can only rely on the physical coalescence of cellulose powder, which is far less efficient than the synergistic demulsification mechanism of chemical and physical methods, resulting in a longer demulsification time and insufficient dehydration rate. Although the biodegradability is still good, this is mainly due to the biocompatibility of cellulose powder itself. As a high-efficiency biosurfactant, the long-chain alkyl group in the molecular structure of hydrophobized chitinous oligosaccharide enables it to quickly migrate and embed into the oil-water interface layer, reducing the interfacial tension and ultimately tearing the interfacial film.

[0045] Through comparison and analysis of the related data in the table, it can be known that the green and environment-friendly polyether demulsifier prepared by the application not only has excellent and rapid and efficient demulsification performance, but also has excellent environmental compatibility and biodegradability, so it is shown that the green and environment-friendly polyether demulsifier and the preparation method thereof have wider market prospect and are more suitable for promotion.

[0046] In the description of the present specification, the description referring to the terms "one embodiment", "an example", "a specific example" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0047] The preferred embodiments of the application disclosed above are only used to help explain the application. The preferred embodiments do not describe all the details and limit the application to the specific embodiments. Obviously, many modifications and variations can be made according to the content of the present specification. The present specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the application, so that those skilled in the art can well understand and utilize the application. The application is limited only by the claims and their full scope and equivalents.

Claims

1. A green and environmentally friendly polyether demulsifier, characterized in that: The method is prepared from the following raw materials in parts by weight: 5-15 parts of a bio-starter, 60-80 parts of propylene oxide, 20-40 parts of ethylene oxide, 0.3-0.8 parts of a catalyst, and 100-150 parts of deionized water; The preparation method of the biological initiator comprises the following steps: S1: chitosan oligosaccharide powder and long-chain glycidyl ether are mixed in a mass ratio of 1: (0.2-0.5), placed in a supercritical carbon dioxide reactor, introduced with carbon dioxide, and reacted at 50-70°C for 2-4 hours to obtain hydrophobic chitosan oligosaccharide; S2: adding cellulose powder into the reactor while maintaining the supercritical state, stirring and reacting for 1-2 hours. After the reaction is completed, releasing the pressure, recovering the carbon dioxide gas, obtaining a coarse material, taking out the coarse material and crushing it to obtain the bio-initiator.

2. A green and environmentally friendly polyether demulsifier according to claim 1, characterized in that, The pressure of the supercritical carbon dioxide reactor is 15-25MPa.

3. A green and environmentally friendly polyether demulsifier according to claim 2, characterized in that, The preparation method of the chitosan oligosaccharide powder comprises the following steps: mixing chitosan with a 2% acetic acid solution at a mass ratio of 1:(19-32) to obtain an acetic acid solution of chitosan oligosaccharide powder, adding immobilized chitosanase, performing enzymolysis at 45-55°C and pH=5.0-5.5 for 6-10 hours, centrifuging after enzymolysis, taking the supernatant, adjusting the pH to 7.0-8.0 with a sodium hydroxide solution, filtering to obtain a precipitate, vacuum drying at 50-60°C, and grinding to obtain the chitosan oligosaccharide powder.

4. A green and environmentally friendly polyether demulsifier according to claim 1, characterized in that, The preparation method of the cellulose powder comprises the following steps: S1: Dispersing nanocellulose in deionized water to prepare a first suspension with a mass fraction of 1-3%, ultrasonically treating for 25-35 minutes, and adding the ionic liquid monomer 1-aminoethyl-3-methylimidazolium bromide into the deionized water to prepare a second solution with a mass fraction of 5-10%; S2: Add the second solution dropwise to the first suspension under stirring, and adjust the pH to 4.5-5.5 with dilute acetic acid to obtain a premixed solution; S3: adding carbodiimide hydrochloride to the premixed solution, reacting at 50-60° C. for 12-24 hours, dialyzing for 3-5 days after the reaction, and spray drying after the dialysis to obtain the cellulose powder.

5. A green and environmentally friendly polyether demulsifier according to claim 4, characterized in that, The mass ratio of the ionic liquid monomer 1-aminoethyl-3-methylimidazolium bromide to the nanocellulose in S1 is (0.5-1.5): 1, and the mass of the carbodiimide hydrochloride in S3 is 10-20% of the mass of the ionic liquid monomer 1-aminoethyl-3-methylimidazolium bromide.

6. A green and environmentally friendly polyether demulsifier according to claim 3, characterized in that, The mass of the immobilized chitosanase is 1%-2% of the mass of chitosan.

7. A green and environmentally friendly polyether demulsifier according to claim 2, characterized in that, The long-chain glycidyl ether is at least one of glycidyl lauryl ether and glycidyl hexadecyl ether.

8. A green and environmentally friendly polyether demulsifier according to claim 2, characterized in that, The mass ratio of the hydrophobized chitosan oligosaccharide to the cellulose powder is 100: (8-12).

9. The green and environmentally friendly polyether demulsifier according to claim 1, characterized in that: The catalyst is a double metal cyanide complex catalyst.

10. A method for preparing the green and environmentally friendly polyether demulsifier according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1: Under nitrogen protection, add the bio-initiator, catalyst and deionized water into the autoclave, stir and react at a speed of 200-400 rpm, and heat to 100-120° C. to obtain a reactant; S2: After vacuum dehydration of the reactants for 0.5-1 h, propylene oxide is added, and the reaction is carried out at a pressure of 0.2-0.4 MPa and a temperature of 115-125° C. for 2-3 h. Ethylene oxide is added and the reaction is continued under the same conditions for 2-3 h. After the reaction is completed, the reactants are cooled to 60-70° C. and discharged to obtain the green and environmentally friendly polyether demulsifier.

Images