A magnetically responsive dendritic heavy oil demulsifier, a preparation method and application thereof

Abstract

The application discloses a tree-shaped heavy oil demulsifier with magnetic response, a preparation method and application thereof. The demulsifier comprises composite magnetic nano-particles, the composite magnetic nano-particles have a magnetic particle core and a polymer coated on the outer surface of the magnetic particle core, the magnetic particle core is modified superparamagnetic ferroferric oxide nano-particles, and the polymer is alkyl phenol formaldehyde resin polyoxyethylene polyoxypropylene ether. The application successfully realizes quick demulsification of emulsion under the action of magnetic response at low temperature, the amount of the magnetic particles is small during demulsification, and the demulsification process is environment-friendly, efficient and low in cost.

Description

Technical Field

[0001] This invention belongs to the field of demulsifier technology, and specifically relates to a dendritic heavy oil demulsifier with magnetic response, its preparation method and application. Background Technology

[0002] Demulsification is a critical technological step in oil recovery. Conventional demulsification methods, such as high-temperature demulsification, electrolytic demulsification, or the addition of demulsifiers, are energy-intensive, slow, and have low separation efficiency, failing to meet the requirements of economical, energy-saving, and efficient oil recovery. In recent years, with the increasing complexity of produced fluid composition and the growing problem of emulsified oil in order to improve oil recovery rates, the development of environmentally friendly, efficient, and low-cost demulsification materials and methods has become urgent.

[0003] Demulsification is the process of eliminating the stable conditions of an emulsion, causing dispersed droplets to aggregate and separate into layers. It includes physical and chemical demulsification methods. Physical demulsification methods, such as heating, electric field demulsification, and ultrasonic methods, use physical and mechanical means to break the stability of the emulsion. Chemical demulsification involves adding a demulsifier to replace the emulsifier molecules in the original emulsion and increase the oil / water interfacial tension to achieve demulsification. Physical demulsification methods are typically energy-intensive and slow, but environmentally friendly and do not generate additional waste. Chemical demulsification methods usually do not require additional energy and are faster, but the inability to reuse the material increases the difficulty of waste treatment. Therefore, there is an urgent need for a demulsification material that combines the environmental friendliness of physical demulsification with the energy efficiency and rapid response of chemical demulsification, while also being reusable. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the present invention provides a magnetically responsive dendritic heavy oil demulsifier, its preparation method and application, wherein the demulsifier can achieve environmentally friendly, efficient and low-cost demulsification.

[0005] In one aspect, the present invention provides a dendritic heavy oil demulsifier with magnetic response, comprising composite magnetic nanoparticles having a magnetic particle core and a polymer coating the outer surface of the magnetic particle core, wherein the magnetic particle core is modified superparamagnetic iron oxide nanoparticles and the polymer is alkylphenol resin polyoxyethylene polyoxypropylene ether.

[0006] As a specific embodiment of the present invention, the particle size of the composite magnetic nanoparticles is 300-500 nm.

[0007] As a specific embodiment of the present invention, the saturation magnetization of the composite magnetic nanoparticles is 60-100 emu / g, preferably 80 emu / g.

[0008] As a specific embodiment of the present invention, the modified superparamagnetic iron oxide nanoparticles are silane coupling agent modified superparamagnetic iron oxide nanoparticles.

[0009] Preferably, the silane coupling agent modified superparamagnetic iron oxide nanoparticles are obtained by mixing superparamagnetic iron oxide nanoparticles, silane coupling agent and solvent under an inert atmosphere, and reacting at a certain temperature for a certain time.

[0010] Preferably, the silane coupling agent comprises carboxylated polyethylene glycol triethoxysilane;

[0011] Preferably, the solvent includes ethanol and toluene;

[0012] Preferably, the molar ratio of the superparamagnetic iron oxide nanoparticles to the silane coupling agent is 1:(1-5);

[0013] Preferably, the reaction temperature is 95–135°C and the reaction time is 7–10 h.

[0014] As a specific embodiment of the present invention, the polymer is C3-C10 alkylphenol resin polyoxyethylene polyoxypropylene ether, preferably nonylphenol resin polyoxyethylene polyoxypropylene ether.

[0015] Preferably, the nonylphenolic resin polyoxyethylene polyoxypropylene ether is obtained by mixing nonylphenolic resin, catalyst and propylene oxide under an inert atmosphere, reacting for a certain time at a certain temperature and pressure, and then mixing the reaction product with ethylene oxide and reacting for a certain time at a certain temperature and pressure.

[0016] Preferably, the weight ratio of ethylene oxide to propylene oxide is 1:2 to 4, and more preferably 1:3;

[0017] Preferably, the amount of nonylphenolic resin used is 0.5 to 1% by weight, based on the total weight of the raw materials;

[0018] Preferably, the catalyst is an alkaline compound, preferably potassium hydroxide; preferably, the amount of potassium hydroxide used is 0.4-0.6% by weight, preferably 0.5% by weight, based on the total weight of the raw materials.

[0019] Preferably, the conditions for the two reactions are the same: the reaction temperature is 120–140°C, the pressure is 0.2–0.4 MPa, and the reaction time is 10–14 h.

[0020] A second aspect of the present invention provides a method for preparing the aforementioned magnetically responsive dendritic heavy oil demulsifier, comprising: mixing alkylphenol resin polyoxyethylene polyoxypropylene ether, modified superparamagnetic iron oxide nanoparticles, a catalyst, and a solvent, and reacting them at a certain temperature for a certain time.

[0021] As a specific embodiment of the present invention, the catalyst includes HATU; and / or, the solvent includes DMF; and / or, the molar ratio of the alkylphenol resin polyoxyethylene polyoxypropylene ether, modified superparamagnetic iron oxide nanoparticles to the catalyst is 0.1-0.3:0.7-0.9:0.01-0.05, preferably 0.2:0.8:0.03; and / or, the reaction temperature is 20-40°C, and the reaction time is 1-5 h.

[0022] A third aspect of the present invention provides a demulsification method, comprising using the aforementioned magnetically responsive dendritic heavy oil demulsifier to demulsify an emulsion, comprising:

[0023] i) Disperse a magnetically responsive dendritic heavy oil demulsifier in water;

[0024] ii) Mix the liquid obtained in step i) with the emulsion and disperse by shearing;

[0025] iii) Place the liquid obtained in step ii) in an external magnetic field for a certain period of time.

[0026] As a specific embodiment of the present invention, the amount of the magnetically responsive dendritic heavy oil demulsifier used is 0.3 to 0.5% by weight, preferably 0.4% by weight, based on the total weight of the raw materials.

[0027] As a specific embodiment of the present invention, the shearing rate for shear dispersion is 4000-6000 r / min, the time is 0.5-2 min, preferably 5000 r / min for 1 min; and / or, the magnetic field strength of the external magnetic field is 0.3-0.5 T, preferably 0.4 T.

[0028] In a specific embodiment of the present invention, the emulsion is an oil-in-water emulsion or an oil-in-water emulsion. The preparation of the oil-in-water emulsion includes: dissolving sodium dodecylbenzenesulfonate (SDBS) as an emulsifier in deionized water, adding it to the oil phase and the water phase at an oil-to-water volume ratio of (1-4):2, and emulsifying it on a shear emulsifier to obtain an emulsion with SDBS as the emulsifier. The oil phase is selected from n-hexane, n-decane, or n-heptane, the water phase is deionized water, and the emulsifier content is 300 ppm to 700 ppm. The emulsification method is: emulsifying on a shear emulsifier at a speed of 3000-10000 r / min for 20-90 s, preferably at a speed of 5000 r / min for 1 min.

[0029] The beneficial effects of this invention are as follows:

[0030] The demulsifier provided by this invention has a core-shell structure, with modified superparamagnetic iron oxide nanoparticles as the core and alkylphenol resin polyoxyethylene polyoxypropylene ether as the shell. The alkylphenol resin polyoxyethylene polyoxypropylene ether has high surface activity, enabling the demulsifier to quickly penetrate the external phase of the emulsion and move to the oil-water interface. When an external magnetic field is introduced at the bottom of the emulsion, the magnetic particles in the demulsifier, specifically the modified superparamagnetic iron oxide nanoparticles, are subjected to magnetic force, disrupting the original force equilibrium. The magnetic particles then move towards the bottom of the emulsion, resulting in oil-water separation. This invention successfully achieves rapid demulsification of magnetically responsive emulsions at low temperatures, requires a small amount of magnetic particles, and the demulsification process is environmentally friendly, efficient, and low-cost. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0032] Figure 1 The molecular structural formula of nonylphenolic resin polyoxyethylene polyoxypropylene ether;

[0033] Figure 2 This is a morphology diagram of the dendritic heavy oil demulsifier with magnetic response of the present invention;

[0034] Figure 3 The hysteresis loop of the dendritic heavy oil demulsifier with magnetic response of the present invention;

[0035] Figure 4A It is the original emulsion;

[0036] Figure 4B The emulsion after shearing and dispersion with the addition of a demulsifier;

[0037] Figure 4C This refers to the emulsion after demulsification. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] Unless otherwise specified, the experimental methods used in the following examples are conventional methods.

[0040] Unless otherwise specified, all materials and reagents used in the following examples are commercially available.

[0041] In the quantitative experiments described below, three replicate experiments were conducted, and the average value of the results was taken.

[0042] The superparamagnetic iron oxide nanoparticles used in the following examples were purchased from Aladdin Reagents.

[0043] Example 1

[0044] I. Preparation of nonylphenolic resin polyoxyethylene polyoxypropylene ether:

[0045] ① Add xg of nonylphenol aldehyde resin as an initiator to a high-pressure reactor, and then add yg of KOH solid catalyst, which accounts for 0.5% of the total raw material mass.

[0046] ② For the sealed reaction vessel system, dry nitrogen is used to displace the air in the high-pressure vessel, feed vessel, and feed pipe.

[0047] ③ Install the heating furnace and start heating. While heating, use a vacuum pump to evacuate the vacuum. Stop evacuating the vacuum when the temperature reaches 100℃. Add mg of propylene oxide to the feed vessel, pressurize to 0.4MPa, open the feed valve to start feeding, control the reaction temperature at 130℃ and the pressure at 0.3MPa, and react for 7 hours.

[0048] ④ After the reaction is complete, age for 1 hour, cool to 100℃, and reduce the pressure to atmospheric pressure.

[0049] ⑤ Add ng of ethylene oxide to the feed reactor and react for 5 hours under the same conditions as in step ③. Neutralize the reaction product with phosphoric acid to obtain nonylphenolic resin polyoxyethylene polyoxypropylene ether, with the molecular structure shown below. Figure 1 As shown in the figure. Where n:m = 1:3, x is 0.5 wt% of the total raw material, and y is 0.5 wt% of the total raw material.

[0050] II. Preparation of silane coupling agent modified superparamagnetic iron oxide nanoparticles:

[0051] In a nitrogen atmosphere, 0.01 mol Fe3O4 nanoparticles were dispersed in 80 ml of ethanol. Using 200 ml of toluene as solvent, 0.02 mol of carboxyl polyethylene glycol triethoxysilane reagent was added and reacted at 110 °C for 9 h to obtain black particles with carboxyl groups on the surface, which are silane coupling agent modified superparamagnetic iron oxide nanoparticles.

[0052] III. Preparation of dendritic heavy oil demulsifiers with magnetic response:

[0053] Using NN dimethylformamide (DMF) as a solvent, nonylphenol resin polyoxyethylene polyoxypropylene ether and 2-(7-azobenzenetriazole-1-yl)-N,N,N',N'-tetramethylurea hexafluorophosphate (HATU) were added to silane coupling agent modified superparamagnetic iron oxide nanoparticles. The molar ratio of silane coupling agent modified superparamagnetic iron oxide nanoparticles, nonylphenol resin polyoxyethylene polyoxypropylene ether and HATU was 0.8:0.2:0.03. The reaction was carried out at 25℃ for 3 h to obtain a dendritic heavy oil demulsifier with magnetic response.

[0054] Experimental Example

[0055] 1. The prepared dendritic heavy oil demulsifier with magnetic response was characterized. For example... Figure 2 As shown, the dendritic heavy oil demulsifier with magnetic response has good dispersibility, and the particle size is about 300-500 nm.

[0056] 2. The magnetic properties of the prepared dendritic heavy oil demulsifier with magnetic response were characterized. For example... Figure 3 As shown, the hysteresis loops show no coercivity or remanence, indicating that it possesses superparamagnetism. The hysteresis loops also reveal that its saturation magnetization is 80 emu / g.

[0057] 3. Study on demulsification effect

[0058] 3.1 Preparation of Emulsion

[0059] The emulsifier SDBS was dissolved in secondary water. Hexane and secondary water containing SDBS were added to a container at an oil-to-water volume ratio of 2:1. The emulsifier concentration was 350 ppm. The mixture was emulsified for 1 minute at a speed of 5000 r / min on a shear emulsifier to obtain a stable SDBS emulsion.

[0060] 3.2 Demulsification Experiment

[0061] A magnetically responsive dendritic heavy oil demulsifier was ultrasonically dispersed in deionized water. 1 ml of the deionized water containing the magnetically responsive dendritic heavy oil demulsifier was added to an SDBS-stabilized emulsion. The demulsifier concentration was 0.4 wt%. After shearing and dispersion at 5000 r / min for 1 min on a shear mill, the emulsion was magnetically demulsified at room temperature (25°C) on a large magnet (0.4 T). Figures 4A-4C As shown, the prepared emulsion has a very good emulsification effect, with all oil and water forming an emulsion. After adding a dendritic heavy oil demulsifier with magnetic response and introducing an external magnetic field, the emulsion demulsification effect is very good, achieving complete separation of oil and water. A clear oil-water interface can be observed, and the demulsification time is 2 minutes.

[0062] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

Claims

1. A dendritic heavy oil demulsifier with magnetic response, characterized in that, The demulsifier comprises composite magnetic nanoparticles, the composite magnetic nanoparticles have a magnetic particle core and a polymer coated on the outer surface of the magnetic particle core, the magnetic particle core is modified superparamagnetic ferroferric oxide nanoparticles, and the polymer is alkyl phenol formaldehyde resin polyoxyethylene polyoxypropylene ether.

2. The magnetic responsive dendritic heavy oil demulsifier according to claim 1, characterized in that, The composite magnetic nanoparticles have a particle size of 300-500 nm.

3. The magnetic responsive dendritic thick oil demulsifier according to claim 1, characterized in that, The composite magnetic nanoparticles have a saturation magnetization of 60-100 emu / g.

4. The magnetic responsive dendrimeric heavy oil demulsifier according to claim 3, characterized in that, The composite magnetic nanoparticles have a saturation magnetization of 80 emu / g.

5. The magnetic responsive dendrimeric heavy oil demulsifier according to claim 1, wherein, The silane coupling agent modified superparamagnetic ferroferric oxide nanoparticles are obtained by mixing superparamagnetic ferroferric oxide nanoparticles, a silane coupling agent and a solvent in an inert atmosphere, and then reacting at a certain temperature for a certain time; the solvent comprises ethanol and toluene; the molar ratio of the superparamagnetic ferroferric oxide nanoparticles to the silane coupling agent is 1:(1-5); the reaction temperature is 95-135 ℃, and the reaction time is 7-10 h.

6. The magnetic responsive dendrimeric heavy oil demulsifier according to claim 1, wherein, The polymer is C3-C10 alkyl phenol formaldehyde resin polyoxyethylene polyoxypropylene ether.

7. The magnetic responsive dendrimeric heavy oil demulsifier according to claim 6, characterized in that, The polymer is nonyl phenol formaldehyde resin polyoxyethylene polyoxypropylene ether.

8. The magnetic responsive dendrimeric heavy oil demulsifier according to claim 7, characterized in that, The nonyl phenol formaldehyde resin polyoxyethylene polyoxypropylene ether is obtained by mixing nonyl phenol formaldehyde resin, a catalyst and propylene oxide in an inert atmosphere, and then reacting at a certain temperature and pressure for a certain time, and then mixing the reaction product with ethylene oxide, and then reacting at a certain temperature and pressure for a certain time; the weight ratio of the ethylene oxide to the propylene oxide is 1:2-4; the amount of the nonyl phenol formaldehyde resin is 0.5-1% by weight based on the total weight of the raw materials; the catalyst is an alkaline compound; the conditions of the two reactions are the same, the reaction temperature is 120-140 ℃, the pressure is 0.2-0.4 MPa, and the reaction time is 10-14 h.

9. The magnetic responsive dendrimeric heavy oil demulsifier according to claim 8, characterized in that, The weight ratio of the ethylene oxide to the propylene oxide is 1:3; the catalyst is potassium hydroxide, and the amount of the potassium hydroxide is 0.4-0.6% by weight.

10. The magnetic responsive dendrimeric heavy oil demulsifier according to claim 9, characterized in that, The amount of the potassium hydroxide is 0.5% by weight.

11. A method for preparing the magnetic responsive dendrimeric heavy oil demulsifier according to any one of claims 1 to 10, characterized in that, The preparation method comprises mixing alkyl phenol formaldehyde resin polyoxyethylene polyoxypropylene ether, modified superparamagnetic ferroferric oxide nanoparticles, a catalyst and a solvent, and then reacting at 20-40 ℃ for 1-5 h.

12. The method for preparing the magnetically responsive dendritic heavy oil demulsifier according to claim 11, characterized in that, The catalyst comprises 2-(7-azophenylpropyltriazol-1-yl)-N,N,N',N'-tetramethylurea hexafluorophosphate; and / or, the solvent comprises DMF.

13. The method for preparing the magnetically responsive dendritic heavy oil demulsifier according to claim 11, characterized in that, The molar ratio of the alkyl phenol formaldehyde resin polyoxyethylene polyoxypropylene ether, the modified superparamagnetic ferroferric oxide nanoparticles and the catalyst is 0.1-0.3:0.7-0.9:0.01-0.

05.

14. The method for preparing the magnetically responsive dendritic heavy oil demulsifier according to claim 13, characterized in that, The molar ratio of the alkyl phenol formaldehyde resin polyoxyethylene polyoxypropylene ether, the modified superparamagnetic ferroferric oxide nanoparticles and the catalyst is 0.2:0.8:0.

03.

15. A method of breaking emulsions, characterized in that, The method for demulsifying the emulsion by using the magnetic responsive dendritic heavy oil demulsifier according to any one of claims 1-10, the method comprising: i) dispersing the magnetic responsive dendritic heavy oil demulsifier in water; ii) mixing the liquid obtained in step i) with the emulsion and shearing and dispersing; iii) placing the liquid obtained in step ii) in an external magnetic field for a certain time.

16. The method of claim 15, wherein, The magnetic responsive dendritic heavy oil demulsifier is used in an amount of 0.3-0.5% by weight based on the total weight of the raw materials.

17. The method of claim 16, wherein the emulsion is broken by, The magnetic responsive dendritic heavy oil demulsifier is used in an amount of 0.4% by weight based on the total weight of the raw materials.

18. The method of claim 15, wherein, The emulsion is an oil-in-water emulsion or a water-in-oil emulsion; and / or, the shearing speed of the shearing and dispersing is 4000-6000 r / min, and the time is 0.5-2 min; and / or, the magnetic field strength of the external magnetic field is 0.3-0.5 T.

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