Dendritic thick oil demulsifier with magnetic response as well as preparation method and application of dendritic thick oil demulsifier

Abstract

The invention discloses a tree-shaped heavy oil demulsifier with magnetic response as well as a preparation method and application thereof. The demulsifying agent comprises composite magnetic nano particles, the composite magnetic nano particles are provided with magnetic particle inner cores and polymers coated on the outer surfaces of the magnetic particle inner cores, the magnetic particle inner cores are modified superparamagnetic ferroferric oxide nano particles, and the polymers are alkyl phenolic resin polyoxyethylene polyoxypropylene ether. Rapid demulsification of the emulsion with the magnetic response effect at the low temperature is successfully achieved, the using amount of magnetic particles is small during demulsification, and the demulsification process is environmentally friendly, efficient and low in cost.

Description

Technical Field

[0001] The invention belongs to the technical field of demulsifiers, and particularly relates to a tree-like heavy oil demulsifier with magnetic response, a preparation method and application thereof. Background Art

[0002] Demulsification is a key process in the oil recovery process. Conventional demulsification methods represented by high temperature, electro-demulsification or adding demulsifiers have high energy consumption, slow demulsification and low separation efficiency, and can no longer meet the requirements of economic, energy-saving and efficient oil recovery development. In recent years, in order to improve the recovery rate, the composition of the produced fluid has become more complex and the problem of emulsified oil has become increasingly serious. It is urgent to develop environmentally friendly, efficient and low-cost demulsification materials and methods.

[0003] Demulsification is the process of eliminating the stable conditions of the emulsion, aggregating and stratifying the dispersed droplets. It includes physical demulsification and chemical demulsification. Heating method, electric field demulsification method, ultrasonic method, etc. belong to physical demulsification, that is, physical and mechanical means are used to break the stability of the emulsion; chemical demulsification is to add demulsifiers to replace the emulsifier molecules in the original emulsion and increase the oil / water interfacial tension to achieve demulsification. Physical demulsification usually has high energy consumption and slow demulsification speed, but it is environmentally friendly and does not produce additional waste. Chemical demulsification usually does not require additional energy and is faster, but it cannot be reused, which increases the difficulty of waste liquid treatment. Therefore, there is an urgent need for a demulsification material that is both environmentally friendly and energy-saving, fast-responding, and reusable for chemical demulsification methods. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a tree-like heavy oil demulsifier with magnetic response, a preparation method and application thereof, wherein the demulsifier can achieve environmentally friendly, efficient and low-cost demulsification.

[0005] In one aspect of the present invention, a tree-like heavy oil demulsifier with magnetic response is provided, which comprises composite magnetic nanoparticles, wherein the composite magnetic nanoparticles have a magnetic particle core and a polymer coated on the outer surface of the magnetic particle core, wherein the magnetic particle core is a modified superparamagnetic ferrosoferric oxide nanoparticle, and the polymer is an alkylphenol-formaldehyde resin polyoxyethylene polyoxypropylene ether.

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

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

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

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

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

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

[0012] Preferably, the molar ratio of the superparamagnetic ferroferric 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-formaldehyde resin polyoxyethylene polyoxypropylene ether, preferably nonylphenol-formaldehyde resin polyoxyethylene polyoxypropylene ether;

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

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

[0017] Preferably, the nonylphenol-formaldehyde resin is used in an amount of 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 is 0.4 to 0.6 weight %, preferably 0.5 weight %, based on the total weight of the raw materials;

[0019] Preferably, the conditions of 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] The second aspect of the present invention provides a method for preparing the aforementioned magnetically responsive tree-like heavy oil demulsifier, comprising: mixing alkylphenol-formaldehyde resin polyoxyethylene polyoxypropylene ether, modified superparamagnetic ferrosoferric 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-formaldehyde resin polyoxyethylene polyoxypropylene ether, the modified superparamagnetic ferrosoferric oxide nanoparticles and 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 1-5h.

[0022] The third aspect of the present invention provides a demulsification method, which uses the above-mentioned tree-like heavy oil demulsifier with magnetic response to demulsify the emulsion, comprising:

[0023] i) dispersing a magnetically responsive tree-like heavy oil demulsifier in water;

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

[0025] iii) placing 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 is 0.3-0.5% 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 dispersion has a shearing rate of 4000-6000 r / min, a time of 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] As a specific embodiment of the present invention, the emulsion is an oil-in-water emulsion or an oil-in-water emulsion, and the preparation of the oil-in-water emulsion includes: dissolving the emulsifier sodium dodecylbenzene sulfonate (SDBS) in secondary water, adding the oil phase and the water phase in an oil-water volume ratio of (1 to 4): 2, and emulsifying on a shear emulsifier to obtain an emulsion with SDBS as an emulsifier. Among them, the oil phase is selected from n-hexane, n-decane or n-heptane, the water phase is secondary water, and the emulsifier content is 300ppm to 700ppm. The emulsification method is: emulsifying at a speed of 3000 to 10000 r / min on a shear emulsifier for 20 to 90s, preferably, emulsifying at a speed of 5000 r / min for 1min.

[0029] The beneficial effects of the present invention are:

[0030] The demulsifier provided by the present invention has a core-shell structure, with modified superparamagnetic ferroferric oxide nanoparticles as the core and alkylphenol-formaldehyde resin polyoxyethylene polyoxypropylene ether as the shell, and the alkylphenol-formaldehyde resin polyoxyethylene polyoxypropylene ether has high surface activity, so that the demulsifier can quickly pass through the outer 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 particle-modified superparamagnetic ferroferric oxide nanoparticles in the demulsifier are acted upon by the magnetic field force, and the original force balance state is destroyed, and the magnetic particles move to the bottom of the emulsion, so that the emulsion oil and water are separated. The present invention successfully realizes the rapid demulsification of the magnetic response emulsion at low temperature, the amount of magnetic particles used during demulsification is small, and the demulsification process is environmentally friendly, efficient, and low in cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0032] Figure 1 It is the molecular structure formula of nonylphenolic resin polyoxyethylene polyoxypropylene ether;

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

[0034] Figure 3 is the hysteresis loop of the tree-like heavy oil demulsifier with magnetic response of the present invention;

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

[0036] Figure 4B The emulsion is sheared and dispersed by adding demulsifier;

[0037] Figure 4C It is the emulsion after demulsification. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work 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, the materials and reagents used in the following examples can be obtained from commercial sources.

[0041] The quantitative tests in the following examples were all repeated three times, and the results were averaged.

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

[0043] Example 1

[0044] 1. Preparation of nonyl phenolic resin polyoxyethylene polyoxypropylene ether:

[0045] ① Add xg of nonylphenol-formaldehyde resin as a starter into a high-pressure reactor, and then add yg of solid KOH catalyst accounting for 0.5% of the total raw material mass.

[0046] ② Seal the reactor system and use dry nitrogen to displace the air in the autoclave, feed kettle and feed pipe.

[0047] ③ Install the heating furnace and start heating. Use the vacuum pump to evacuate the air while heating. Stop evacuating the air when the temperature reaches 100°C. Add mg propylene oxide into the feed kettle and pressurize it to 0.4MPa. Open the feed valve and start feeding. Control the reaction temperature at 130°C and the pressure at 0.3MPa. React for 7h.

[0048] ④ After the reaction is completed, age for 1 hour, cool to 100°C, and reduce the pressure to normal pressure.

[0049] ⑤ Add ng ethylene oxide to the feed kettle and react for 5 hours under the same conditions as step ③. The reaction product is neutralized with phosphoric acid to obtain nonyl phenolic resin polyoxyethylene polyoxypropylene ether, the molecular structure of which is as follows: Figure 1 As shown, n:m=1:3, x is 0.5wt% of the total raw material amount, and y is 0.5wt% of the total raw material amount.

[0050] 2. Preparation of silane coupling agent modified superparamagnetic ferroferric oxide nanoparticles:

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

[0052] 3. Preparation of tree-like heavy oil demulsifier with magnetic response:

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

[0054] Experimental example

[0055] 1. Characterize the prepared magnetically responsive dendritic heavy oil demulsifier. Figure 2 As shown, the magnetically responsive dendritic heavy oil demulsifier has good dispersibility, and the particle size is about 300-500 nm.

[0056] 2. Characterize the magnetic properties of the prepared magnetically responsive dendritic heavy oil demulsifier. Figure 3 As shown in the figure, the hysteresis loop has no remanence and residual magnetism, indicating that it has superparamagnetism. It can also be seen from the hysteresis loop that its saturation magnetization intensity is 80emu / g.

[0057] 3. Study on demulsification effect

[0058] 3.1 Preparation of emulsion

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

[0060] 3.2 Demulsification experiment

[0061] The magnetically responsive dendritic oil demulsifier was ultrasonically dispersed in secondary water, and 1 ml of the secondary water dispersed with the magnetically responsive dendritic oil demulsifier was added to the SDBS-stabilized emulsion, the demulsifier concentration was 0.4 wt %, and after shearing and dispersing at a speed of 5000 r / min for 1 min on a shearing machine, it was placed on a large magnet (0.4 T) at room temperature 25°C for magnetic response demulsification, as shown in FIG. Figures 4A to 4C As shown. It can be seen that the prepared emulsion has a good emulsification effect, and the oil and water have all formed an emulsion. After adding the magnetically responsive tree-like heavy oil demulsifier and introducing an external magnetic field, the emulsion demulsification effect is very good, achieving complete separation of oil and water, and an obvious oil-water interface can be observed. The demulsification time is 2 minutes.

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

Claims

1. A magnetically responsive tree-like heavy oil demulsifier, characterized in that: The demulsifier comprises composite magnetic nanoparticles, which have a magnetic particle core and a polymer coated on the outer surface of the magnetic particle core. The magnetic particle core is a modified superparamagnetic ferrosoferric oxide nanoparticle, and the polymer is an alkylphenol-formaldehyde resin polyoxyethylene polyoxypropylene ether.

2. The magnetically responsive tree-like heavy oil demulsifier according to claim 1, characterized in that: The particle size of the composite magnetic nanoparticles is 300-500nm.

3. The magnetically responsive tree-like heavy oil demulsifier according to claim 1, characterized in that: The saturation magnetization intensity of the composite magnetic nanoparticles is 60 to 100 emu / g, preferably 80 emu / g.

4. The magnetically responsive dendritic oil demulsifier according to claim 1, characterized in that: The modified superparamagnetic ferroferric oxide nanoparticles are superparamagnetic ferroferric oxide nanoparticles modified by a silane coupling agent; Preferably, the silane coupling agent modified superparamagnetic ferroferric oxide nanoparticles are obtained by mixing superparamagnetic ferroferric oxide nanoparticles, a silane coupling agent and a solvent under an inert atmosphere and reacting them at a certain temperature for a certain period of time; Preferably, the silane coupling agent comprises carboxyl polyethylene glycol triethoxysilane; Preferably, the solvent includes ethanol and toluene; Preferably, the molar ratio of the superparamagnetic ferroferric oxide nanoparticles to the silane coupling agent is 1:(1-5); Preferably, the reaction temperature is 95-135° C., and the reaction time is 7-10 h.

5. The magnetically responsive dendritic oil demulsifier according to claim 1, characterized in that: The polymer is C3-C10 alkylphenol-formaldehyde resin polyoxyethylene polyoxypropylene ether, preferably nonylphenol-formaldehyde resin polyoxyethylene polyoxypropylene ether; Preferably, the nonylphenolic resin polyoxyethylene polyoxypropylene ether is obtained by mixing nonylphenolic resin, a catalyst and propylene oxide under an inert atmosphere, reacting at a certain temperature and pressure for a certain time, and then mixing the reaction product with ethylene oxide and reacting at a certain temperature and pressure for a certain time; Preferably, the weight ratio of ethylene oxide to propylene oxide is 1:2 to 4, preferably 1:3; Preferably, the nonylphenol-formaldehyde resin is used in an amount of 0.5 to 1% by weight based on the total weight of the raw materials; Preferably, the catalyst is an alkaline compound, preferably potassium hydroxide; preferably, the amount of potassium hydroxide is 0.4 to 0.6 weight %, preferably 0.5 weight %, based on the total weight of the raw materials; Preferably, the conditions of 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.

6. A method for preparing the magnetically responsive dendritic heavy oil demulsifier according to any one of claims 1 to 5, characterized in that: The preparation method comprises: mixing alkylphenolic resin polyoxyethylene polyoxypropylene ether, modified superparamagnetic ferrosoferric oxide nanoparticles, a catalyst and a solvent, and reacting them at a certain temperature for a certain time.

7. The method for preparing the magnetically responsive dendritic heavy oil demulsifier according to claim 6, characterized in that: The catalyst includes HATU; and / or the solvent includes DMF; and / or the molar ratio of the alkylphenol-formaldehyde resin polyoxyethylene polyoxypropylene ether, the modified superparamagnetic ferrosoferric oxide nanoparticles and 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 1-5h.

8. A demulsification method, characterized in that: The method of using the magnetically responsive tree-like heavy oil demulsifier according to any one of claims 1 to 5 to demulsify the emulsion comprises: i) dispersing a magnetically responsive tree-like heavy oil demulsifier in water; ii) mixing the liquid obtained in step i) with the emulsion and dispersing by shearing; iii) placing the liquid obtained in step ii) in an external magnetic field for a certain period of time.

9. The demulsification method according to claim 8, characterized in that: Based on the total weight of the raw materials, the amount of the magnetically responsive tree-like heavy oil demulsifier is 0.3-0.5% by weight, preferably 0.4% by weight.

10. The demulsification method according to claim 8, characterized in that: The emulsion is an oil-in-water emulsion or an oil-in-water emulsion; and / or, the shear rate of the 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.

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