An ionic compound, a demulsifier and a preparation method and application thereof

Abstract

The application discloses an ionic compound, a demulsifier and a preparation method and application thereof. The preparation method of the ionic compound comprises the following steps: performing an opening ring reaction on glycerol triglycidyl ether and N,N-dibutyl ethanolamine to obtain an opening ring product; and performing an ionization reaction on the opening ring product and a halogenated hydrocarbon in a solvent A. The prepared ionic compound is used as the demulsifier for crude oil emulsion, and has the characteristics of high demulsification efficiency, low demulsification temperature and fast demulsification rate. In addition, the preparation method is simple in steps, low in raw material cost and suitable for industrial production.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of oil-water emulsion treatment, and particularly relates to an ionic compound, a demulsifier and a preparation method and application thereof. BACKGROUND

[0002] For most oilfields, water injection oil production is an inevitable process. Therefore, the yield of crude oil emulsion with high water content is increasing. These emulsions cannot be simply regarded as a two-phase mixture of oil and water. Due to the presence of natural surfactants, such emulsions are very stable. The natural active substances in crude oil mainly include asphaltene, resin, naphthenic acid and solid particles (such as clay or wax). Among them, asphaltene can be adsorbed on the oil-water interface to form a rigid interface film, effectively wrapping water droplets and preventing their coalescence. Therefore, the stability of oil-water emulsion is a serious challenge in oil production, which can cause many disturbances to the operation of upstream separators (upper and lower separators) and the entire refining process. Therefore, the stability of oil-water emulsion brings great challenges to the oil industry. Chemical demulsifiers are widely used because of their fast demulsification speed and high demulsification efficiency.

[0003] Chemical demulsification refers to the separation of oil and water in emulsion by adding various chemical agents through chemical reactions. Chemical demulsifiers can replace natural emulsifiers adsorbed on the oil-water interface, reduce the viscoelasticity and strength of the oil-water interface film, and promote the coalescence of droplets, thereby realizing the separation of oil and water. Common chemical demulsifiers include polymer surfactants, nanoparticles and ionic liquids, such as ethylene oxide-propylene oxide (EO-PO) block copolymer, silicon polyether, dendrimer, biodegradable polymer surfactant and nanoparticle-based demulsifier.

[0004] However, these demulsifiers have problems such as complex preparation process, high raw material cost, poor demulsification effect and potential environmental pollution risk. SUMMARY

[0005] In view of the deficiencies in the prior art, the purpose of the present application is to provide an ionic compound, a demulsifier and a preparation method and application thereof, aiming to solve the problems of poor demulsification performance of the demulsifier, high raw material cost of the demulsifier and potential environmental pollution in the prior art

[0006] The purpose of the present application is achieved by the following technical solutions:

[0007] An ionic compound, the chemical structural formula of which is as follows:

[0008] .

[0009] The ion compound provided by the application is prepared by ring-opening of glycerol triketal triglycidyl ether and connecting halogenated hydrocarbon, and has a three-branched structure, and has the characteristics of a central hydrophilic and a peripheral hydrophobic, and the hydrophobic part is composed of an external carbon chain, which gives it hydrophobicity. Meanwhile, due to the presence of three long carbon chains, it has better dispersibility in an oil phase and can more effectively interact with natural surface active substances, thereby destroying the interfacial film, promoting the coalescence of water droplets and realizing oil-water separation. In addition, the ion compound is prepared by ring-opening of glycerol triketal triglycidyl ether and connecting halogenated hydrocarbon, and the synthesis steps are simple and convenient. The ion compound demulsifier prepared by the application can realize rapid demulsification at a lower temperature and can effectively reduce the interfacial tension of oil and water.

[0010] The preparation method of the ion compound comprises the following steps: ring-opening reaction of glycerol triketal triglycidyl ether and N,N-dibutyl ethanolamine to obtain a ring-opening product; and ionization reaction of the ring-opening product and halogenated hydrocarbon in a solvent A to obtain the ion compound.

[0011] Preferably, the molar ratio of glycerol triketal triglycidyl ether and N,N-dibutyl ethanolamine is 1:3.

[0012] Preferably, the molar ratio of glycerol triketal triglycidyl ether and halogenated hydrocarbon is 1:3.

[0013] Preferably, the glycerol triketal triglycidyl ether is purchased from the Microlin Reagent Co., Ltd., has an epoxy equivalent weight of 143-154 g / eq, a viscosity of 100-300 mPa·s and a CAS number of G887780.

[0014] Preferably, the temperature of the ring-opening reaction is 110-130 DEG C, and the time is 8-10 h. Specifically, the temperature of the ring-opening reaction is 120 DEG C, 122 DEG C, 124 DEG C, 126 DEG C, 128 DEG C, 130 DEG C or any value between 110 DEG C and 130 DEG C; and the time of the ring-opening reaction is 8 h, 9 h, 10 h or any value between 8 h and 10 h.

[0015] Preferably, the temperature of the ionization reaction is 60-70 DEG C, and the time is 12-14 h. Specifically, the temperature of the ionization reaction is 60 DEG C, 62 DEG C, 64 DEG C, 66 DEG C, 68 DEG C, 70 DEG C or any value between 60 DEG C and 70 DEG C; and the time of the ionization reaction is 12 h, 13 h, 14 h or any value between 12 h and 14 h.

[0016] The above reaction temperature needs to ensure that the reaction proceeds smoothly, and a too low reaction temperature will lead to incomplete reaction, and a too high reaction temperature will evaporate the solvent; the reaction time can be appropriately extended within a proper range, and the influence on the reaction is small within the above range.

[0017] Preferably, the halogenated hydrocarbon is at least one of bromododecane, bromohexadecane, chlorohexadecane and bromooctadecane.

[0018] Preferably, the solvent A is at least one of ethanol and xylene.

[0019] A demulsifier comprising an ionic compound.

[0020] Use of the demulsifier in demulsification of crude oil emulsion.

[0021] The use of the demulsifier in demulsification of crude oil emulsion comprises the following steps: firstly, dissolving the ionic compound in the solvent B to obtain a solution, and then mixing the solution with the crude oil emulsion for demulsification. After the demulsification, the oil-water interface is clear, the water content in the oil phase is low, the required demulsification temperature is low, and the demulsification cost is low.

[0022] Preferably, the mass percentage of the ionic compound in the solution is 0.2-1wt%.

[0023] Preferably, the solvent B is at least one of water, ethanol and xylene.

[0024] Preferably, the volume ratio of the solution to the crude oil emulsion is 1: (10-20).

[0025] Preferably, the demulsification temperature is 50-70℃, and the time is 0.5-3h. More preferably, the demulsification time is 2-3h.

[0026] The preparation method of the ionic compound provided by the present application has the advantages of simple synthesis steps, low required demulsification temperature and high demulsification efficiency. The use of the demulsifier has important significance for the chemical demulsification problems of high demulsification cost, low demulsification efficiency and high required demulsification temperature of the crude oil emulsion in the petroleum industry. Due to the three long carbon chains, the demulsifier has better dispersibility in the oil phase and can produce stronger force with natural interfacial active substances, thereby changing the tension of the oil-water interface, promoting the coalescence of water droplets, and realizing oil-water separation.

[0027] Compared with the prior art, the present application has the following advantages:

[0028] The demulsifier provided by the present application has high surface activity, good thermal stability and good dispersibility in the oil phase, and is suitable for the treatment of crude oil emulsion, and has the characteristics of high demulsification efficiency, low demulsification temperature and fast demulsification rate. In addition, the preparation method provided by the present application has simple steps and low raw material cost. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 The infrared spectrum of the ionic compound prepared in Example 1. DETAILED DESCRIPTION

[0030] In order to make the objects, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not intended to limit the present application.

[0031] Example 1

[0032] A method for preparing an ionic compound, the steps are as follows:

[0033] Glycerol triketal (0.01 mol) and N, N-dibutyl ethanolamine (0.03 mol) are added to a three-necked flask and heated in an oil bath at 120°C for 8h to obtain a ring-opening product, the structural formula of which is shown as formula I:

[0034] (I),

[0035] Then, the ring-opening product is cooled, the temperature is reduced to 65°C, 30mL of ethanol is added, then bromododecane (0.03 mol) is added, and the reaction is continued for 12h to obtain an ionic product. Finally, the ethanol is evaporated by vacuum distillation to obtain the final product, i.e. the ionic compound, the structural formula of which is shown as formula II:

[0036] (II).

[0037] Figure 1 The infrared spectrum of the ionic compound prepared in Example 1 is shown in the figure, in which the peaks at 2925.53 cm -1 and 2854.18 cm -1 correspond to the anti-symmetric and symmetric stretching vibrations of -CH2- respectively, and the peak at 1093.46 cm -1 corresponds to the C-N stretching vibration, which indicates the successful synthesis of the target product.

[0038] Example 2

[0039] Example 2 provides a method for preparing an ionic compound, which is different from Example 1 only in that "bromooctadecane is used instead of bromododecane", and the other steps and conditions are the same as those of Example 1.

[0040] Example 3

[0041] Example 3 provides a method for preparing an ionic compound, which is different from Example 1 only in that "the ring-opening product is cooled, the temperature is reduced to 100-110°C, and 30mL of dimethylbenzene is added", and the other steps and conditions are the same as those of Example 1.

[0042] Example 4

[0043] Example 4 provides a method for preparing an ionic compound, the difference compared with Example 1 is only that "the time of the ring-opening reaction is increased from 8 h to 12 h", and other steps, conditions and Example 1 are the same.

[0044] Example 5

[0045] Example 5 provides a method for preparing an ionic compound, the difference compared with Example 1 is only that "chlorohexadecane is used to replace bromododecane", and other steps, conditions and Example 1 are the same.

[0046] Test section

[0047] In order to avoid repetition, the crude oil emulsion used in the following tests is prepared according to the following steps:

[0048] 150 parts by weight of crude oil is added to 350 parts by weight of deionized water and stirred and mixed, heated to 60°C, then stirred at a speed of 11000 r / min for 20 minutes, and the stirring process is repeated one to three times until a stable water-in-oil emulsion, i.e. a crude oil emulsion, is obtained. In order to ensure the accuracy of the test, the crude oil emulsion is tested by repeating the stirring process three times, which is more uniform.

[0049] 1. Commercial demulsifier PDB9429 is used as Comparative Example 1, RI-14A is used as Comparative Example 2, DI-18 is used as Comparative Example 3, and 1301 is used as Comparative Example 4. The demulsification performance of the ionic compounds prepared in Examples 1-5 as demulsifiers in the crude oil emulsion is compared and tested, and the specific steps are as follows:

[0050] The ionic compounds prepared in Examples 1-5 are added to xylene / ethanol (75:25) respectively to prepare a solution with a mass fraction of 1%, i.e. Experimental Groups 1-5. Commercial demulsifier PDB9429 (purchased from BASF Company) is used as Comparative Example 1, RI-14A (purchased from BASF Company) is used as Comparative Example 2, DI-18 (purchased from BASF Company) is used as Comparative Example 3, and 1301 (purchased from BASF Company) is used as Comparative Example 4. The commercial demulsifiers in the comparative examples are added to xylene / ethanol (volume ratio 75:25) respectively to prepare a solution with a mass fraction of 1%, i.e. Comparative Groups 1-4.

[0051] Experimental Groups 1-5 and Comparative Groups 1-4 are added to the above-mentioned crude oil emulsion in a volume ratio of 1:19, then fully shaken and mixed uniformly, then transferred to a 50°C water bath and left to stand for 2 h, and the dehydration rate is measured. The results are shown in Table 1.

[0052] Table 1 Demulsification results of Experimental Groups 1-5 and Comparative Groups 1-4

[0053]

[0054] Note: "Demulsifier (mg / L)" in the table refers to the concentration of the demulsifier in the crude oil emulsion.

[0055] As can be seen from Table 1, the demulsifiers prepared in Examples 1-5 all have very good demulsification performance, but due to the differences in preparation conditions, such as the types of halogenated alkanes, the types of solvents and the reaction time, etc., the demulsification efficiency differs. For example, from the data of Example 1 and Example 2, it can be seen that appropriately shortening the length of the hydrophobic chain is conducive to improving the demulsification efficiency. In addition, the conditions of Example 3 and Example 4 are changed, so the obtained demulsification efficiency is also different. Compared with the commercial demulsifiers in the comparative group, the demulsifiers provided by the present application show more excellent demulsification ability.

[0056] 2, based on the demulsifier prepared in Example 1, solutions with different concentrations are used to characterize the demulsification performance of the demulsifier with different concentrations in the crude oil emulsion.

[0057] Different weight parts of the demulsifier prepared in Example 1 are added to dimethylbenzene / ethanol (volume ratio 75:25) to prepare demulsifier solutions with mass fractions of 0.2%, 0.4%, 0.6%, 0.8% and 1% respectively, and the obtained samples are respectively recorded as experimental groups 7-11; the blank group is 0%, and the sample is recorded as experimental group 6.

[0058] 1 volume part of the above experimental groups 6-11 is added to 19 volume parts of the crude oil emulsion, then mixed uniformly by oscillation, and then transferred to a 50℃ water bath for 2h, and the dehydration rate is measured, and the results are shown in Table 2.

[0059] Table 2 demulsification results of experimental groups 6-11

[0060]

[0061] Note: "Demulsifier (mg / L)" in the table refers to the concentration of the demulsifier in the crude oil emulsion.

[0062] As can be seen from Table 2, the demulsifier provided by the present application has good demulsification performance, and a demulsification efficiency of 94.46% can be achieved with 200 mg / L of the demulsifier, and when the concentration of the demulsifier is 500 mg / L, the demulsification efficiency reaches 98.63%.

[0063] 3, based on the demulsifier prepared in Example 1, experimental groups 12-14 are established in turn, for characterizing the demulsification performance of the demulsifier under different temperatures and times.

[0064] The demulsifier prepared in Example 1 is added to dimethylbenzene / ethanol (volume ratio 75:25) to prepare a solution with a mass fraction of 1%.

[0065] 1 part by volume of the above demulsifier was added to 19 parts by volume of the crude oil emulsion and then mixed uniformly by oscillation, and then transferred to a water bath set at different temperatures and allowed to stand for 2 h, and the dehydration rate was measured at 60 min, 90 min and 120 min, and the results are shown in Table 3.

[0066] Table 3 demulsification results of experimental groups 12-14

[0067]

[0068] As shown in Table 3, the demulsifier provided by the present application can achieve a demulsification efficiency of 97.46% at 50℃ for 60 min, 97.53% at 60℃ for 60 min, and 98.92% at 70℃ for 60 min.

[0069] In summary, the demulsifier of the present application has the advantages of simple synthesis steps, low required demulsification temperature, fast demulsification rate and high demulsification efficiency. It has great significance for solving the problems of high cost, low demulsification efficiency and high required demulsification temperature in the chemical demulsification of crude oil emulsion in the petroleum industry. Specifically, the three long carbon chains of the demulsifier make it have better dispersibility in the oil phase and stronger force with natural interfacial active substances, easily penetrate the interfacial film, change the tension of the oil-water interface, promote the coalescence of water droplets, and thus achieve oil-water separation.

[0070] The specific embodiments of the present application described above do not constitute a limitation on the scope of protection of the present application. Any various other corresponding changes and modifications made in accordance with the technical concept of the present application shall be included in the scope of protection of the claims of the present application.

Claims

1. An ionic compound, characterized in that, The chemical structural formula is as follows: 。 2. A method of preparing the ionic compound of claim 1, characterized in that, The method comprises the following steps: performing ring-opening reaction on glycerol triacrylate and N,N-dibutyl ethanolamine to obtain a ring-opening product; and performing ionization reaction on the ring-opening product and a halogenated hydrocarbon in a solvent A to obtain the ionized compound.

3. The method for preparing the ionic compound according to claim 2, wherein: The molar ratio of the glycerol triacrylate and the N,N-dibutyl ethanolamine is 1:3; The molar ratio of the glycerol triacrylate and the halogenated hydrocarbon is 1:

3.

4. The method for preparing the ionic compound according to claim 2, wherein: The ring-opening reaction is performed at a temperature of 110-130 DEG C for 8-10 h; The ionization reaction is performed at a temperature of 60-70 DEG C for 12-14 h.

5. The method for preparing the ionic compound according to any one of claims 2 to 4, characterized in that: The halogenated hydrocarbon is bromododecane; The solvent A is at least one of ethanol and dimethylbenzene.

6. A demulsifier characterized by, The ionized compound of claim 1.

7. The use of the demulsifier of claim 6 in demulsification of crude oil emulsion.

8. Use according to claim 7, characterized in that, The method comprises the following steps: firstly dissolving the ionized compound in a solvent B to obtain a solution, and then mixing the solution with crude oil emulsion to perform demulsification.

9. Use according to claim 8, characterized in that, The mass percentage of the ionized compound in the solution is 0.2-1 wt%; The volume ratio of the solution to the crude oil emulsion is 1: (10-20).

10. Use according to claim 8, characterized in that, The solvent B is at least one of water, ethanol and dimethylbenzene; The demulsification is performed at a temperature of 50-70 DEG C for 0.5-3 h.

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