Preparation method of a magnetic recyclable heavy oil emulsion breaker
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- XIAN HUAQI ZHONGXIN TECH DEV CO LTD
- Filing Date
- 2024-05-21
- Publication Date
- 2026-05-29
Smart Images
Figure CN118546694B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of chemical engineering, and in particular to a method for preparing a magnetic recyclable heavy oil emulsion demulsifier. Background Technology
[0002] Crude oil contains various natural emulsifiers, such as asphaltenes, naphthenic acids, fatty acids, and gums. These organic compounds act as surfactants, causing crude oil and water to form very stable crude oil emulsions. Emulsions can cause problems such as crude oil flow blockage, low separation efficiency, increased equipment operating burden, and even equipment corrosion, increasing the costs of transportation, processing, and separation units. In the later stages of oilfield processing, demulsifiers are often used to achieve oil-water separation; however, existing demulsifiers suffer from numerous problems, including high chemical dosage, low demulsification efficiency, difficulty in degradation, and secondary pollution. Because the demulsification problem of heavy oil / water emulsions remains severe, there is an urgent need to develop a new, green, recyclable demulsifier capable of breaking down heavy oil / water emulsion systems. Summary of the Invention
[0003] To address the technical problems existing in the background art, this invention proposes a method for preparing a magnetically recyclable heavy oil emulsion demulsifier. The demulsifier is prepared by using an ammonia-based precursor to generate carbon dots, which are then combined with magnetic nanoparticles. Surface modification with a silane coupling agent is then performed to obtain composite nanoparticles that can stably exist at the oil-water interface. These nanoparticles are then used as demulsifiers in heavy oil / water emulsion systems to achieve separation of the oil and water phases. Furthermore, this demulsifier exhibits magnetic responsiveness and can be recycled and reused using a magnet.
[0004] The present invention proposes a method for preparing a magnetically recyclable heavy oil emulsion demulsifier, comprising the following steps:
[0005] S1. Add 0.1-1g of ammonia and 1-10mL of buffer solution to 10-30mL of solvent, and heat in a microwave oven to obtain carbon dots with amino-rich surfaces.
[0006] S2. Under the condition of stirring at room temperature, 1-10g of ferric chloride hexahydrate, 1-10g of sodium acetate and 0.1-5g of polyethylene glycol are added to 10-50mL of ethylene glycol to prepare a mixed solution. Then, the solution is placed in a reaction vessel and heated. After washing, magnetic nanoparticles of iron oxide are obtained.
[0007] S3. Carbon dots rich in amino groups on the surface and magnetic nanoparticles of iron oxide are ultrasonically precipitated in 5-20 mL of deionized water at a mass ratio of 5:1-20:1 and then dried to obtain carbon dot-modified magnetic nanoparticles of iron oxide.
[0008] S4. After uniformly mixing carbon dot-modified iron oxide magnetic nanoparticles and silane coupling agents in a mass ratio of 2:1-10:1 in 50-200 mL of solvent, a surface modification reaction is carried out to obtain a magnetic recyclable demulsifier.
[0009] Preferably, in S1, the ammonia-like substance in the carbon dot precursor is one or more of dopamine, phenylenediamine, benzidine, ethylenediamine, and triethylamine.
[0010] Preferably, in step S1, the buffer solution required for carbon dot preparation is one or more of the following: Tris, Phosphate Buffered Solution (PBS), N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid buffer (HEPES), and 2-(N-morpholine)ethanesulfonic acid buffer (MES).
[0011] Preferably, in step S1, the solvent required for carbon dot preparation is one or more of propylene glycol, ethylene glycol, methanol, ethanol, glycerol, toluene, butanediol, methyl ethyl ketone, diethyl ether, and water.
[0012] Preferably, in step S1, the microwave oven has a heating power of 750W and a heating time of 1-10 minutes.
[0013] Preferably, in step S2, the relative molecular mass of the polyethylene glycol is 1000-4000, the heating temperature of the reactor is 150-250℃, and the heating time is 1-10h.
[0014] Preferably, in step S3, the ultrasonic deposition time is 10-60 min and the drying time is 1-5 h.
[0015] Preferably, in step S4, the silane coupling agent is one or more of methyltrisiloxane, ethyltrisiloxane, propenyltrimethoxysilane, propenyltripropoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltripropoxysilane, methyldiethoxysilane, vinyltrimethoxysilane, vinyltripropoxysilane, and isobutylenedimethoxysilane.
[0016] Preferably, in step S4, the solvent is one or more of propylene glycol, ethylene glycol, methanol, ethanol, toluene, butanediol, methyl ethyl ketone, and diethyl ether.
[0017] Preferably, in step S4, the reaction temperature for surface modification is 20-100℃, and the reaction time is 3-12h.
[0018] The beneficial effects of this invention are:
[0019] Compared with existing demulsifier preparation processes that are characterized by low demulsification efficiency, inability to recycle, and complex preparation, the demulsifier prepared by the method of the present invention can be recycled and reused by adsorption with a magnet. It also has good demulsification performance, capable of demulsifying not only alkane oil emulsions but also heavy oil emulsions. Furthermore, the preparation method of this demulsifier is simple and environmentally friendly, which is conducive to its widespread use in the future. Attached Figure Description
[0020] Figure 1 The fluorescence spectra of carbon dots at different excitation wavelengths are shown.
[0021] Figure 2 Infrared spectra of each step in the demulsifier process;
[0022] Figure 3 A graph showing the photoluminescence yield of the demulsifier product;
[0023] Figure 4 Graphs showing the demulsification effects of different light oil shear emulsions;
[0024] Figure 5 A comparison chart showing the demulsification effects of different demulsifier mass fractions. Detailed Implementation
[0025] The present invention will be further explained below with reference to specific embodiments. Example 1
[0026] This embodiment proposes a method for preparing a magnetically recyclable heavy oil emulsion demulsifier, comprising the following steps:
[0027] S1. Add 0.1g of ammonia and 1mL of buffer solution to 10mL of solvent, place in a microwave oven and heat to obtain carbon dots with amino-rich surface. The ammonia precursor of carbon dots is dopamine, the buffer solution is tris(hydroxymethyl)aminomethane buffer (Tris), the solvent is propylene glycol, the microwave oven heating power is 750W, and the heating time is 1min.
[0028] S2. Under room temperature and stirring conditions, 1g of ferric chloride hexahydrate, 1g of sodium acetate and 0.1g of polyethylene glycol with a relative molecular mass of 1000 were added to 10mL of ethylene glycol to prepare a mixed solution. The solution was then placed in a reaction vessel and heated to 150℃ for 1h. After washing, magnetic nanoparticles of iron oxide were obtained.
[0029] S3. Carbon dots rich in amino groups on the surface and magnetic nanoparticles of iron oxide at a mass ratio of 5:1 were ultrasonically precipitated in 5 mL of deionized water and dried. The ultrasonic precipitation time was 10 min and the drying time was 1 h to obtain carbon dot modified magnetic nanoparticles of iron oxide.
[0030] S4. After uniformly mixing carbon dot-modified iron oxide magnetic nanoparticles and silane coupling agent in 50 mL of solvent at a mass ratio of 2:1, a surface modification reaction is carried out at a reaction temperature of 20℃ and a reaction time of 3 h to obtain a magnetic recyclable demulsifier. The silane coupling agent is methyltrisiloxane or ethyltrisiloxane, and the solvent is propylene glycol. Example 2
[0031] This embodiment proposes a method for preparing a magnetically recyclable heavy oil emulsion demulsifier, comprising the following steps:
[0032] S1. Add 0.5g of ammonia and 5mL of buffer solution to 20mL of solvent, place in a microwave oven and heat to obtain carbon dots with amino-rich surface. The ammonia precursor of carbon dots is dopamine, the buffer solution is tris(hydroxymethyl)aminomethane buffer (Tris), the solvent is propylene glycol, the microwave oven heating power is 750W, and the heating time is 5min.
[0033] S2. Under room temperature and stirring conditions, 5g of ferric chloride hexahydrate, 5g of sodium acetate and 3g of polyethylene glycol with a relative molecular mass of 1000 were added to 30mL of ethylene glycol to prepare a mixed solution. The solution was then placed in a reaction vessel and heated to 200℃ for 5h. After washing, magnetic nanoparticles of iron oxide were obtained.
[0034] S3. Carbon dots rich in amino groups on the surface and magnetic nanoparticles of iron oxide at a mass ratio of 13:1 were ultrasonically precipitated in 13 mL of deionized water and dried. The ultrasonic precipitation time was 40 min and the drying time was 3 h to obtain carbon dot modified magnetic nanoparticles of iron oxide.
[0035] S4. After uniformly mixing carbon dot-modified iron oxide magnetic nanoparticles and silane coupling agents in 130 mL of solvent at a mass ratio of 5:1, a surface modification reaction is carried out at a reaction temperature of 60℃ and a reaction time of 8 h to obtain a magnetic recyclable demulsifier. The silane coupling agents are methyltrisiloxane and ethyltrisiloxane, and the solvent is propylene glycol. Example 3
[0036] This embodiment proposes a method for preparing a magnetically recyclable heavy oil emulsion demulsifier, comprising the following steps:
[0037] S1. Add 1g of ammonia and 10mL of buffer solution to 30mL of solvent, place in a microwave oven and heat to obtain carbon dots with amino-rich surface. The ammonia precursor of carbon dots is dopamine, the buffer solution is tris(hydroxymethyl)aminomethane buffer (Tris), the solvent is propylene glycol, the microwave oven heating power is 750W, and the heating time is 10min.
[0038] S2. Under room temperature and stirring conditions, 10g of ferric chloride hexahydrate, 10g of sodium acetate and 5g of polyethylene glycol with a relative molecular mass of 1000 were added to 50mL of ethylene glycol to prepare a mixed solution. The solution was then placed in a reaction vessel and heated to 250℃ for 10h. After washing, magnetic nanoparticles of iron oxide were obtained.
[0039] S3. Carbon dots rich in amino groups on the surface and magnetic nanoparticles of iron oxide at a mass ratio of 20:1 were ultrasonically precipitated in 20 mL of deionized water and dried. The ultrasonic precipitation time was 60 min and the drying time was 5 h to obtain carbon dot modified magnetic nanoparticles of iron oxide.
[0040] S4. After uniformly mixing carbon dot-modified iron oxide magnetic nanoparticles and silane coupling agents in 200 mL of solvent at a mass ratio of 10:1, a surface modification reaction is carried out at a reaction temperature of 100℃ and a reaction time of 12 h to obtain a magnetic recyclable demulsifier. The silane coupling agents are methyltrisiloxane and ethyltrisiloxane, and the solvent is propylene glycol.
[0041] The demulsifiers prepared in Examples 1-3 above were tested respectively, such as... Figure 1 As shown, the fluorescence spectrum exhibits great diversity. When detecting amino-rich carbon dots, the emission peak changes from 440 nm to 455 nm, and the excitation wavelength changes from 330 nm to 380 nm. It can be seen that the optimal excitation wavelength for amino-rich carbon dots is 360 nm.
[0042] By performing directional analysis of the functional groups in the sample, relevant characteristic peaks are obtained, such as... Figure 2 As shown in the figure, the spectral information of characteristic peaks of amino-rich carbon dots, carbon dot-modified iron oxide, and magnetic recyclable demulsifiers can be observed. 3400 cm⁻¹ -1 and 1600cm -1 The peak values indicate that both the catechol-OH group and the aromatic ring are present in the three substances mentioned above, demonstrating that the functional group grafting in the experimental process was successful.
[0043] Fluorescence of quinine sulfate with an absorbance of 0.1 was measured at 360 nm, and fluorescence of a demulsifier product with an absorbance of 0.1 was measured at its optimal excitation wavelength of 360 nm. The integrated areas of the emission peaks of the two products were compared, and the curves are shown below. Figure 3 As shown, the photoluminescence yield of the demulsifier product is calculated to be 3.5% according to the following formula.
[0044]
[0045] φ x and φ std The quantum yields of the analyte and the standard, I, are respectively. xand I std A represents the integrated fluorescence intensity of the analyte and the standard, respectively, measured experimentally. x and A std η represents the absorbance of the analyte and the standard at the incident light at the excitation wavelength, respectively. x and η std These are the refractive indices of the analyte and the standard, respectively.
[0046] Five light oils—n-hexadecane, n-decane, n-heptane, cyclohexane, and n-hexane—were mixed with water at a ratio of 99:1. 0.5 g of Span 80 was added, and the mixture was sheared for 10 minutes. The demulsifier added had a mass fraction of 3% in each oil. Figure 4 In the specific implementation shown, 10 ml of the cut emulsion was placed in two bottles, with the left bottle serving as the control group and the right bottle containing the demulsifier. The emulsion was stirred magnetically for 30 seconds to ensure that the demulsifier was evenly dispersed in the emulsion. Then, the right bottle was attracted by a magnet. It was observed that the emulsion on the right was clearer than the solution on the left, indicating that the demulsifier successfully broke the thick oil emulsion system.
[0047] Emulsions with demulsifier mass fractions of 0%, 1%, 2%, 3%, 4%, and 5% were prepared, and 0.5 g of Span 80 was added and sheared for 10 min, as follows: Figure 5 In the specific embodiment shown, 10 ml of each of the cut emulsions were placed in a bottle. The emulsion was demulsified by adding a demulsifier at 80°C and shaking for 10 seconds. Then, a magnet was used to attract the emulsion on the right side. It can be observed that the solution gradually becomes clear as the mass fraction of the demulsifier increases, indicating that the demulsifier has successfully demulsified the emulsion.
[0048] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.
Claims
1. A method for preparing a magnetically recyclable heavy oil emulsion demulsifier, characterized in that, Includes the following steps: S1. Add 0.1-1g of ammonia and 1-10mL of buffer solution to 10-30mL of solvent, and heat in a microwave oven to obtain carbon dots with amino-rich surfaces. S2. Under the condition of stirring at room temperature, 1-10g of ferric chloride hexahydrate, 1-10g of sodium acetate and 0.1-5g of polyethylene glycol are added to 10-50mL of ethylene glycol to prepare a mixed solution. Then, the solution is placed in a reaction vessel and heated. After washing, magnetic nanoparticles of iron oxide are obtained. S3. Carbon dots rich in amino groups on the surface and magnetic nanoparticles of iron oxide are ultrasonically precipitated in 5-20 mL of deionized water at a mass ratio of 5:1-20:1 and then dried to obtain carbon dot-modified magnetic nanoparticles of iron oxide. S4. After uniformly mixing carbon dot-modified iron oxide magnetic nanoparticles and silane coupling agents in a mass ratio of 2:1-10:1 in 50-200 mL of solvent, a surface modification reaction is carried out to obtain a magnetic recyclable demulsifier.
2. The method for preparing a magnetically recyclable heavy oil emulsion demulsifier according to claim 1, characterized in that, In S1, the ammonia-like substance in the carbon dot precursor is one or more of dopamine, phenylenediamine, benzidine, ethylenediamine, and triethylamine.
3. The method for preparing a magnetically recyclable heavy oil emulsion demulsifier according to claim 1, characterized in that, In S1, the buffer solution required for carbon dot preparation is one or more of the following: Tris, Phosphate Buffer (PBS), N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid buffer (HEPES), and 2-(N-morpholine)ethanesulfonic acid buffer (MES).
4. The method for preparing a magnetically recyclable heavy oil emulsion demulsifier according to claim 1, characterized in that, In step S1, the solvent required for carbon dot preparation is one or more of propylene glycol, ethylene glycol, methanol, ethanol, glycerol, toluene, butanediol, methyl ethyl ketone, diethyl ether, and water.
5. The method for preparing a magnetically recyclable heavy oil emulsion demulsifier according to claim 1, characterized in that, In step S1, the microwave oven has a heating power of 750W and a heating time of 1-10 minutes.
6. The method for preparing a magnetically recyclable heavy oil emulsion demulsifier according to claim 1, characterized in that, In step S2, the relative molecular mass of the polyethylene glycol is 1000-4000, the heating temperature of the reactor is 150-250℃, and the heating time is 1-10h.
7. The method for preparing a magnetically recyclable heavy oil emulsion demulsifier according to claim 1, characterized in that, In step S3, the ultrasonic deposition time is 10-60 min, and the drying time is 1-5 h.
8. The method for preparing a magnetically recyclable heavy oil emulsion demulsifier according to claim 1, characterized in that, In step S4, the silane coupling agent is one or more of methyltrisiloxane, ethyltrisiloxane, propenyltrimethoxysilane, propenyltripropoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltripropoxysilane, methyldiethoxysilane, vinyltrimethoxysilane, vinyltripropoxysilane, and isobutylenedimethoxysilane.
9. The method for preparing a magnetically recyclable heavy oil emulsion demulsifier according to claim 1, characterized in that, In step S4, the solvent is one or more of propylene glycol, ethylene glycol, methanol, ethanol, toluene, butanediol, methyl ethyl ketone, and diethyl ether.
10. The method for preparing a magnetically recyclable heavy oil emulsion demulsifier according to claim 1, characterized in that, In step S4, the reaction temperature for surface modification is 20-100℃, and the reaction time is 3-12h.