Anionic-nonionic surfactant and method for its preparation
By controlling the ratio of tertiary amine groups and sulfonic acid groups through graft copolymerization and addition reaction, an anionic nonionic surfactant suitable for cold recovery of heavy oil was prepared, which solved the problem of uncontrollable molecular structure in the existing process and improved its performance under high temperature and high salt conditions.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- PETROCHINA CO LTD
- Filing Date
- 2024-12-03
- Publication Date
- 2026-06-05
AI Technical Summary
Existing synthesis processes for anionic and nonionic surfactants cannot precisely control their molecular structure, which limits their large-scale application in heavy oil cold recovery. Furthermore, traditional surfactants perform poorly under high temperature and high salt conditions, have a narrow range of applications, and poor penetration performance.
An anionic surfactant with a fine molecular structure was prepared by graft copolymerization of nonylphenol polyoxyethylene ether and propylene oxide under alkaline conditions, followed by substitution reaction with N,N-dimethyl-1,3-propanediamine, and then addition reaction with bisulfite and tetrabutylammonium bromide to control the ratio of tertiary amine groups and sulfonic acid groups.
It achieves fine adjustment of the molecular structure of anionic nonionic surfactants, improving their performance stability and permeability under high temperature and high salt conditions, making them suitable for cold extraction of heavy oil.
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Figure CN122145787A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of oilfield development technology, and in particular to an anionic nonionic surfactant and its preparation method. Background Technology
[0002] Due to the problems of high carbon emissions, high production costs, and low thermal recovery efficiency in heavy oil thermal recovery, the current popular approach to achieve energy reduction, carbon emission reduction, and low-cost extraction is cold oil recovery technology. The core of this technology is the viscosity reducer system, and the core of the viscosity reducer system lies in surfactants. Currently, commonly used surfactants include petroleum sulfonates, petroleum carboxylates, and alkylbenzene sulfonates. However, these surfactants present several unresolved problems for extraction from harsh reservoirs: First, their applicability is narrow; traditional surfactants are only suitable for low-viscosity (viscosity < 10000 mPa·s) reservoirs, and their emulsification and viscosity reduction effects on high-viscosity heavy oil are poor. Second, they have poor temperature and salt resistance; under high-temperature and high-salt conditions, traditional surfactants exhibit strong salt effects, adsorption precipitation, and chromatographic separation defects. Third, their penetration performance is poor; due to differences in the molecular structure of traditional surfactants, and the generally large molecular structure of lipophilic groups, they are difficult to penetrate into the asphaltene fissures of heavy oil.
[0003] Currently, anionic-nonionic surfactants combine the advantages of both anionic and nonionic surfactants, exhibiting excellent viscosity-reducing and emulsifying properties, good thermal properties with good temperature and salt resistance, and good compatibility with crude oil and rock. Therefore, they are the most suitable surfactants for heavy oil cold recovery. However, existing anionic-nonionic surfactant synthesis processes still have several shortcomings. For example, these processes cannot precisely control the molecular structure of anionic-nonionic surfactants, which restricts their large-scale application in heavy oil cold recovery.
[0004] Existing synthesis processes for anionic-nonionic surfactants include: (1) An anionic-nonionic dispersant and its preparation method. This method involves modifying the hydroxyl groups at both ends of polyethylene glycol to synthesize a highly selective terminal amino polyethylene glycol. Then, the terminal amino polyethylene glycol is reacted with sodium benzaldehyde sulfonate to successfully introduce sulfonic acid groups and imine groups into the terminal amino polyethylene glycol. At this time, the hydroxyl group at the other end of the terminal amino polyethylene glycol is used to perform an esterification reaction with the carboxyl group of acrylic acid, thereby obtaining a reactive anionic-nonionic monomer by introducing a terminal double bond. Subsequently, a macromolecular anionic-nonionic dispersant is synthesized under an ATRP four-head initiator. This macromolecular anionic-nonionic dispersant has anionic-nonionic characteristics and can be applied to different solution systems. It can be used to disperse inorganic or organic pigments and has the advantages of good stability, low surface tension and critical micelle concentration, and high dispersibility. (2) A hydrocarbon-based aryl anionic-nonionic surfactant and its preparation method. This method mainly solves the technical problems of poor emulsification performance and low activity of surfactants in existing enhanced oil recovery technologies, especially in heavy oil recovery. This technology utilizes a hydrocarbon-based aryl anionic nonionic surfactant having at least one of the general molecular formulas shown in formula (I), where R1 is any one of C1-C30 aliphatic hydrocarbon groups or aliphatic hydrocarbon groups substituted with aromatic groups; R2 is any one of alkylene, alkenyl, or aryl groups with 0-10 carbon atoms; M is an anionic group; N is any one of cationic or cationic groups; m = 0-100, n = 0-90, p = 0-120, and m, n, and p are all greater than 0. This hydrocarbon-based aryl anionic nonionic surfactant effectively solves the technical problem of poor emulsification ability of existing surfactants and can be used in enhanced oil recovery processes in oil fields. (3) A method for preparing an anionic nonionic reactive emulsifier and its application. The structural formula of this anionic nonionic reactive emulsifier is as follows:
[0005] in n = 5 to 40. The preparation method of the anionic nonionic reactive emulsifier is disclosed, as well as its application in the preparation of polymers. The anionic nonionic reactive emulsifier has excellent properties such as steric stability, high emulsification and dispersion ability, low foaming, low surface tension, and wetting. Applying the anionic nonionic reactive emulsifier to emulsion polymerization, especially styrene-acrylic emulsion polymerization, can prepare high-performance emulsions with high stability, high gloss, and small particle size. (4) An anionic nonionic surfactant and its preparation method. The anionic nonionic surfactant can be prepared by using fatty alcohol polyoxyethylene ether nonionic surfactant, epichlorohydrin, sodium hydroxide and aminobenzenesulfonic acid as raw materials, and then preparing the anionic nonionic surfactant by etherification reaction, ring-closing reaction and nitrogen alkylation reaction. Compared with traditional nonionic surfactants, this anionic-nonionic surfactant has a relatively high cloud point and low surface tension and critical micelle concentration. In addition, compared with the existing anionic-nonionic surfactant sodium fatty alcohol polyoxyethylene ether sulfonate, this anionic-nonionic surfactant has the advantages of readily available raw materials and simple preparation process. Summary of the Invention
[0006] This application provides an anionic nonionic surfactant and its preparation method to solve the following technical problem: how to improve the accuracy of molecular structure regulation during the preparation of anionic nonionic surfactants.
[0007] In a first aspect, this application provides a method for preparing an anionic nonionic surfactant, the method comprising:
[0008] Nonylphenol polyoxyethylene ether and propylene oxide were grafted and copolymerized under alkaline conditions to obtain a polyoxypropylene graft copolymer.
[0009] The N,N-dimethyl-1,3-propanediamine and the polyoxypropylene graft copolymer were subjected to a substitution reaction to obtain a substituted graft copolymer with tertiary amine groups.
[0010] The addition reaction of bisulfite, tetrabutylammonium bromide and zinc oxide with the substituted graft copolymer having tertiary amine groups yields an anionic nonionic surfactant having tertiary amine groups and sulfonic acid groups.
[0011] The amount of tertiary amine group n1 in the anionic nonionic surfactant and the amount of sulfonic acid group n2 in the anionic nonionic surfactant satisfy the relationship n1:n2=(0.2:1.0):(2.0:1.0).
[0012] Optionally, the graft copolymerization reaction is carried out at a temperature of 120℃ to 130℃ and for a duration of 6h to 8h; and / or
[0013] The substitution reaction is carried out at a temperature of 55°C to 65°C for a duration of 12 to 18 hours; and / or
[0014] The addition reaction takes 8 to 10 hours.
[0015] Optionally, the weight m1 of the nonylphenol polyoxyethylene ether and the volume V1 of the propylene oxide satisfy the following relationship: m1:V1=(80~120):(40~80), where if the unit of m1 is g, then the unit of V1 is mL.
[0016] Optionally, the weight m2 of the N,N-dimethyl-1,3-propanediamine and the weight m3 of the polyoxypropylene graft copolymer satisfy the following relationship: m2:m3=(9~11):(45~55).
[0017] Optionally, the volume V2 of the bisulfite and the weight m4 of the substituted graft copolymer satisfy the following relationship: V2:m4=(9~11):(28~32), where if the unit of V2 is mL, then the unit of m4 is g; the mass concentration of the bisulfite is ≥40%.
[0018] Optionally, the amount of nonylphenol polyoxyethylene ether n3 and the amount of polyoxypropylene graft copolymer n4 satisfy the relationship: n3:n4=(0.5:1)~(3.0:1).
[0019] Optionally, the amount of sulfonic acid groups n2 in the anionic-nonionic surfactant and the total weight m5 of the anionic-nonionic surfactant satisfy the following relationship: n2:m5=(0.5:1)~(2.0:1), where if the unit of n2 is mmol, then the unit of m5 is g.
[0020] Optionally, the amount of tertiary amine group n4 in the substituted graft copolymer and the weight m4 of the substituted graft copolymer satisfy the relationship: n4:m4=(0.3:1)~(0.5:1), where if the unit of n4 is mmol, then the unit of m4 is g.
[0021] Secondly, this application provides an anionic nonionic surfactant, which is prepared by the preparation method described in the first aspect, and the molecular structure of the anionic nonionic surfactant is shown in Formula 1.
[0022] RO-(CH2CH2O)x-[CH2CH(CH3)O]y-CH2CH(CH3)OCH2CH[CH2N(CH3)CH2SO3Na]CH2OH,
[0023] In Formula 1, R is a nonylphenol group;
[0024] x is the number of repeating units in polyethylene oxide, and y is the number of repeating units in polypropylene oxide. x and y satisfy the relationship: x + y = 20 ~ 100.
[0025] Optionally, the anionic nonionic surfactant includes a nonylphenol hydrophobic segment and a polyether hydrophilic segment, wherein the mass m5 of the nonylphenol hydrophobic segment and the mass m6 of the polyether hydrophilic segment satisfy the relationship: m5:m6=(1:2)~(1:10).
[0026] The technical solutions provided in this application have the following advantages compared with the prior art:
[0027] This application provides a method for preparing an anionic nonionic surfactant. The method first involves graft copolymerization of nonylphenol polyoxyethylene ether and propylene oxide as raw materials, introducing polyoxypropylene groups into the nonylphenol polyoxyethylene ether. Then, the polyoxypropylene groups undergo a substitution reaction with N,N-dimethyl-1,3-propanediamine, replacing tertiary amine groups into the polyoxypropylene graft copolymer, resulting in a substituted graft copolymer with tertiary amine groups. Next, the substituted graft copolymer with tertiary amine groups undergoes an addition reaction with bisulfite. In this addition reaction, the tertiary amine groups act as linking arms, introducing sulfonic acid groups into the substituted graft copolymer to obtain an amphiphilic surfactant. Anionic and nonionic surfactants are obtained by grafting copolymerization, substitution, and addition reactions to achieve fine adjustment of the molecular structure of anionic and nonionic surfactants. In addition, the amount of tertiary amine groups n1 and the amount of sulfonic acid groups n2 in anionic and nonionic surfactants satisfy the relationship n1:n2=(0.2:1.0):(2.0:1.0). By adjusting the number of tertiary amine groups and sulfonic acid groups in anionic and nonionic surfactants, the molecular structure of anionic and nonionic surfactants can be further adjusted, thereby improving the accuracy of molecular structure control in the preparation process of anionic and nonionic surfactants. Attached Figure Description
[0028] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.
[0029] 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, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0030] Figure 1A schematic flowchart illustrating a method for preparing an anionic nonionic surfactant provided in this application embodiment;
[0031] Figure 2 This is a schematic diagram of an anionic nonionic surfactant provided in Embodiment 1 of this application. Detailed Implementation
[0032] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0033] Various embodiments of this application may exist in the form of a range; it should be understood that the description in the form of a range is merely for convenience and brevity and should not be construed as a hard limitation on the scope of this application; therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and single numerical values within that range; for example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and single numbers within the range such as 1, 2, 3, 4, 5, and 6, regardless of the range; in addition, whenever a numerical range is indicated herein, it means including any referenced number (fraction or integer) within the indicated range.
[0034] In this document, terms such as "comprising" mean "including but not limited to". Relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. "And / or" describes the relationship between related objects, indicating that three relationships can exist; for example, A and / or B can represent: A alone, A and B simultaneously, or B alone; where A and B can be singular or plural. Unless otherwise specified, all raw materials, reagents, instruments, and equipment used in this application are commercially available or can be prepared using existing methods.
[0035] It should be noted that, regarding the prior art (1), (2), (3) and (4) described in the background art, the inventors have found that these prior art have the following problems: (1) The preparation methods used (sulfonation method, esterification coupling method, sulfation method) generally have problems such as long process routes, harsh reaction conditions, poor selectivity, and uncontrollable molecular weight. These problems will lead to increased production costs and unstable product quality. (2) Existing synthesis processes are difficult to precisely control the molecular structure of the product, resulting in the inability to effectively regulate the type, quantity and distribution of hydrophilic and hydrophobic groups, thereby affecting the optimization of product performance. In addition, the synthesis process is difficult to simultaneously take into account excellent viscosity reduction and solubilization performance and good temperature and salt resistance. For example, the introduction of benzene rings through alkylation will result in a low HLB value of the product and poor solubility. (3) Existing synthesis processes are difficult to precisely control the compatibility of products with heavy oil and reservoir rocks. It is difficult to effectively control the molecular weight and lipophilic chain length during the synthesis process, resulting in some products having excessively large molecular weights or excessively long lipophilic chains, which affects their compatibility with heavy oil and thus cannot fully exert their viscosity-reducing and solubilizing effects. In addition, existing synthesis processes are difficult to achieve precise design of molecular chain structures, which makes some products have excessively strong adsorption to rocks, which can easily cause losses and reduce displacement efficiency.
[0036] Figure 1 An exemplary schematic diagram of a method for preparing an anionic nonionic surfactant provided in an embodiment of this application is shown.
[0037] like Figure 1 As shown in the embodiments of this application, a method for preparing an anionic nonionic surfactant is provided, the preparation method comprising:
[0038] S1. Nonylphenol polyoxyethylene ether and propylene oxide are grafted and copolymerized under alkaline conditions to obtain polyoxypropylene graft copolymer.
[0039] S2. The N,N-dimethyl-1,3-propanediamine and the polyoxypropylene graft copolymer are subjected to a substitution reaction to obtain a substituted graft copolymer with tertiary amine groups.
[0040] S3. The substituted graft copolymer having tertiary amine groups is subjected to an addition reaction with bisulfite, tetrabutylammonium bromide and zinc oxide to obtain an anionic nonionic surfactant having tertiary amine groups and sulfonic acid groups.
[0041] The amount of tertiary amine group n1 in the anionic nonionic surfactant and the amount of sulfonic acid group n2 in the anionic nonionic surfactant satisfy the relationship n1:n2=(0.2:1.0):(2.0:1.0).
[0042] The amount of tertiary amine group n1 and the amount of sulfonic acid group n2 in the anionic-nonionic surfactant can satisfy the relationship n1:n2 = 0.2:1.0, 0.4:1.0, 0.6:1.0, 0.8:1.0, 1.0:1.0, 1.2:1.0, 1.4:1.0, 1.6:1.0, 1.8:1.0 or 2.0:1.0.
[0043] It should be noted that this alkaline environment can be achieved by adding alkaline metal salts. The added alkaline metal salts can promote the graft copolymerization reaction between nonylphenol polyoxyethylene ether and propylene oxide, thereby obtaining a sufficient amount of polyoxypropylene graft copolymer.
[0044] It should be noted that when nonylphenol polyoxyethylene ether uses NP-10, the molecular structure of the polyoxypropylene graft copolymer can be: RO-(CH2CH2O)10-[CH2CH(CH3)O]nH; the molecular structure of the substituted graft copolymer with tertiary amine group can be RO-(CH2CH2O)10-[CH2CH(CH3)O]n-CH2CH(CH3)OCH2CH[CH2N(CH3)2]CH2OH.
[0045] In some optional embodiments, the graft copolymerization reaction is carried out at a temperature of 120°C to 130°C for 6 hours to 8 hours; and / or
[0046] The substitution reaction is carried out at a temperature of 55°C to 65°C for a duration of 12 to 18 hours; and / or
[0047] The addition reaction takes 8 to 10 hours.
[0048] In these embodiments, the graft copolymerization reaction temperature can be 120°C to 130°C, and the graft copolymerization reaction time can be 6h to 8h. Polyoxypropylene groups are grafted onto nonylphenol polyoxyethylene ether via graft copolymerization, thereby obtaining a sufficient amount of polyoxypropylene graft copolymer. Additionally, the substitution reaction temperature can be 55°C to 65°C, and the substitution reaction time can be 12h to 18h. The amine groups of N,N-dimethyl-1,3-propanediamine are introduced into the polyoxypropylene graft copolymer via substitution reaction, resulting in a substituted graft copolymer with tertiary amine groups. Furthermore, the addition reaction time can be 8h to 10h. The sulfonic acid groups of bisulfite are introduced into the substituted graft copolymer with tertiary amine groups via addition reaction, thereby obtaining an anionic nonionic surfactant with both tertiary amine and sulfonic acid groups, achieving precise control over the molecular structure of the anionic nonionic surfactant.
[0049] The temperature for the graft copolymerization reaction can be 120℃, 121℃, 122℃, 123℃, 124℃, 125℃, 126℃, 127℃, 128℃, 129℃ or 130℃.
[0050] The graft copolymerization reaction can take 6.0h, 6.5h, 7.0h, 7.5h or 8.0h.
[0051] The temperature for this substitution reaction can be 55℃, 56℃, 57℃, 58℃, 59℃, 60℃, 61℃, 62℃, 63℃, 64℃ or 65℃.
[0052] The substitution reaction can take 12h, 13h, 14h, 15h, 16h, 17h or 18h.
[0053] The addition reaction can take 8.0h, 8.5h, 9.0h, 9.5h, or 10.0h.
[0054] In some optional embodiments, the weight m1 of the nonylphenol polyoxyethylene ether and the volume V1 of the propylene oxide satisfy the relationship: m1:V1=(80~120):(40~80), where if the unit of m1 is g, then the unit of V1 is mL.
[0055] In these embodiments, the weight m1 of nonylphenol polyoxyethylene ether and the volume V1 of propylene oxide can satisfy the relationship: m1:V1=(80~120):(40~60), which can promote the full progress of the graft copolymerization reaction between nonylphenol polyoxyethylene ether and propylene oxide, thereby obtaining a sufficient amount of polyoxypropylene graft copolymer.
[0056] The weight m1 of the nonylphenol polyoxyethylene ether and the volume V1 of propylene oxide can satisfy the following relationship: m1:V1 = 80:40, 80:45, 80:50, 80:55, 80:60, 90:40, 90:45, 90:50, 90:55, 90:60, 100:40, 100:45, 100:50, 100:55, 100:60, 110:40, 110:45, 110:50, 110:55, 110:60, 120:40, 120:45, 120:50, 120:55 or 120:60.
[0057] In some optional embodiments, the weight m2 of the N,N-dimethyl-1,3-propanediamine and the weight m3 of the polyoxypropylene graft copolymer satisfy the relationship: m2:m3=(9~11):(45~55).
[0058] In these embodiments, the weight m2 of N,N-dimethyl-1,3-propanediamine and the weight m3 of the polyoxypropylene graft copolymer can satisfy the relationship: m2:m3=(9~11):(45~55), which can promote the substitution reaction between N,N-dimethyl-1,3-propanediamine and polyoxypropylene graft copolymer to proceed fully, thereby obtaining a sufficient amount of substituted graft copolymer with tertiary amine groups.
[0059] The weight m2 of the N,N-dimethyl-1,3-propanediamine and the weight m3 of the polyoxypropylene graft copolymer can satisfy the following relationship: m2:m3 = 9:45, 9:50, 9:55, 10:45, 10:50, 10:55, 11:45, 11:50 or 11:55.
[0060] In some optional embodiments, the volume V2 of the bisulfite and the weight m4 of the substituted graft copolymer satisfy the following relationship: V2:m4=(9~11):(28~32), where if the unit of V2 is mL, then the unit of m4 is g; the mass concentration of the bisulfite is ≥40%.
[0061] In these embodiments, the volume V2 of the bisulfite and the weight m4 of the substituted graft copolymer can satisfy the relationship: V2:m4=(9~11):(28~32), which can promote the addition reaction between the bisulfite and the substituted graft copolymer to proceed fully, thereby obtaining a sufficient amount of anionic nonionic surfactant.
[0062] The volume V2 of the bisulfite can be 9, 9.5, 10, 10.5 or 11; the weight m4 of the substituted graft copolymer can be 28.0, 28.5, 29.0, 29.5, 30.0, 30.5, 31.0, 31.5 or 32.0.
[0063] In some optional embodiments, the amount of nonylphenol polyoxyethylene ether n3 and the amount of polyoxypropylene graft copolymer n4 satisfy the relationship: n3:n4=(0.5:1)~(3.0:1);
[0064] In these embodiments, the amount of nonylphenol polyoxyethylene ether n3 and the amount of polyoxypropylene graft copolymer n4 can satisfy the relationship: n3:n4 = (0.5:1) to (3.0:1). By adjusting the amounts of nonylphenol polyoxyethylene ether and polyoxypropylene graft copolymer, the molecular weight of the anionic nonionic surfactant can be adjusted, thereby improving the accuracy of the molecular structure of the anionic nonionic surfactant.
[0065] The amount of nonylphenol polyoxyethylene ether n3 and the amount of polyoxypropylene graft copolymer n4 can satisfy the following relationship: n3:n4 = 0.5:1, 1.0:1, 1.5:1, 2.0:1, 2.5:1 or 3.0:1.
[0066] In some optional embodiments, the amount of sulfonic acid groups n2 in the anionic nonionic surfactant and the total weight m5 of the anionic nonionic surfactant satisfy the relationship: n2:m5=(0.5:1)~(2.0:1), where if the unit of n2 is mmol, then the unit of m5 is g;
[0067] In these embodiments, the amount of sulfonic acid groups n2 and the total weight m5 of the anionic-nonionic surfactant can satisfy the relationship: n2:m5=(0.5:1)~(2.0:1), which can ensure that the anionic-nonionic surfactant has a sufficient amount of sulfonic acid groups. The sufficient amount of sulfonic acid groups can make the anionic-nonionic surfactant have good hydrophilicity, thus demonstrating that the anionic-nonionic surfactant has achieved accurate molecular structure adjustment.
[0068] In some optional embodiments, the amount of tertiary amine group n4 in the substituted graft copolymer and the weight m4 of the substituted graft copolymer satisfy the relationship: n4:m4=(0.3:1)~(0.5:1), where if the unit of n4 is mmol, then the unit of m4 is g;
[0069] In these embodiments, the amount of tertiary amine groups n4 in the substituted graft copolymer and the weight m4 of the substituted graft copolymer can satisfy the relationship: n4:m4 = (0.3:1) to (0.5:1), which ensures that the subsequent anionic-nonionic surfactant has a sufficient amount of tertiary amine groups. The sufficient amount of tertiary amine groups can make the anionic-nonionic surfactant have good hydrophobicity, thus demonstrating that the anionic-nonionic surfactant has achieved accurate molecular structure adjustment.
[0070] Figure 2 An exemplary schematic diagram of an anionic nonionic surfactant provided in Embodiment 1 of this application is shown;
[0071] Based on a general inventive concept, such as Figure 2 As shown in the figure, this application provides an anionic nonionic surfactant, which is prepared by the aforementioned preparation method. The molecular structure of the anionic nonionic surfactant is shown in Formula 1.
[0072] RO-(CH2CH2O)x-[CH2CH(CH3)O]y-CH2CH(CH3)OCH2CH[CH2N(CH3)CH2SO3Na]CH2OH,
[0073] Formula 1,
[0074] In Formula 1, R is a nonylphenol group;
[0075] x is the number of repeating units in polyethylene oxide, and y is the number of repeating units in polypropylene oxide. x and y satisfy the relationship: x + y = 20 ~ 100.
[0076] The anionic-nonionic surfactant is obtained based on the preparation method described above. The specific steps of the preparation method can be referred to in the above embodiments. Since the anionic-nonionic surfactant adopts some or all of the technical solutions of the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be elaborated here.
[0077] The number of repeating units x of the polyoxyethylene and the number of repeating units y of the polyoxypropylene can satisfy the following relationship: x + y = 20, 30, 40, 50, 60, 70, 80, 90 or 100.
[0078] It should be noted that this anionic nonionic surfactant uses a hydrophobic tertiary amine group as a linking arm to achieve the connection of a hydrophilic sulfonic acid group, thereby obtaining an amphiphilic anionic nonionic surfactant with a more optimized structure. In addition, this anionic nonionic surfactant retains the polyether chain structure to the greatest extent. By adjusting the mutual relationship between the tertiary amine group, the sulfonic acid group and the polyether chain structure, the molecular weight of the anionic nonionic surfactant can be adjusted, thereby further improving the accuracy of adjusting the molecular structure of the anionic nonionic surfactant.
[0079] It should be noted that the average number of repeating units y in polyoxypropylene is 15 to 25.
[0080] It should be noted that the polyether chain structure (EO and PO units) in this anionic-nonionic surfactant provides excellent amphiphilicity, enabling it to form a stable film at the oil-water interface. Furthermore, the anionic-nonionic surfactant can alter its hydrophilicity on rock surfaces through intermolecular hydrogen bonding. Additionally, the tertiary amine group of this anionic-nonionic surfactant can act as a linking arm to the sulfonic acid group, increasing its molecular flexibility, facilitating rapid rearrangement at the oil-water interface, and allowing for adjustment of its wettability at different pH levels. Moreover, the sulfonic acid group provides strong hydrophilicity and enhances emulsification ability, promoting the transformation of oil-wet rocks into water-wet rocks. Therefore, this anionic-nonionic surfactant exhibits optimal performance at the oil-water-rock three-phase interface through the principles of basic amphiphilicity provided by the polyether chain, increased molecular flexibility and pH responsiveness by the tertiary amine group, and enhanced hydrophilicity by the sulfonic acid group.
[0081] In some optional embodiments, the anionic nonionic surfactant comprises a nonylphenol hydrophobic segment and a polyether hydrophilic segment, wherein the mass m5 of the nonylphenol hydrophobic segment and the mass m6 of the polyether hydrophilic segment satisfy the relationship: m5:m6=(1:2)~(1:10);
[0082] In these embodiments, the anionic nonionic surfactant may include a nonylphenol hydrophobic segment and a polyether hydrophilic segment, and the mass m5 of the nonylphenol hydrophobic segment and the mass m6 of the polyether hydrophilic segment can satisfy the relationship: m5:m6=(1:2)~(1:10), which can promote the anionic nonionic surfactant to have good amphiphilicity, so as to achieve precise adjustment of the molecular structure of the anionic nonionic surfactant.
[0083] The mass m5 of the nonylphenol hydrophobic segment and the mass m6 of the polyether hydrophilic segment can satisfy the following relationship: m5:m6 = 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9 or 1:10.
[0084] The present application is further illustrated below with reference to specific embodiments. Experimental methods in the following embodiments that do not specify specific conditions are generally determined according to industry standards; if no corresponding industry standard exists, they are performed according to general international standards, conventional conditions, or conditions recommended by the manufacturer.
[0085] Example 1
[0086] like Figure 1 As shown, a method for preparing an anionic nonionic surfactant includes:
[0087] S1. A graft copolymerization reaction is carried out between nonylphenol polyoxyethylene ether and propylene oxide under alkaline conditions to obtain a polyoxypropylene graft copolymer; including the following steps:
[0088] Weigh 100g of nonylphenol polyoxyethylene ether (NP-10, average degree of polymerization of polyoxyethylene EO is 10, molecular weight is 680) and place it in a 500mL four-necked flask. Then add 60mL of propylene oxide and 0.5g of solid KOH to obtain the first mixture. Heat the first mixture to 125℃ to carry out the graft copolymerization reaction for 7h to obtain crude polyoxypropylene graft copolymer. Heating was then stopped, and the crude polyoxypropylene graft copolymer was cooled to 45°C. 10 mL of glacial acetic acid was added to the crude polyoxypropylene graft copolymer for neutralization. 120 mL of acetone was then added and stirred for 20 min to allow the mixture of polyoxypropylene graft copolymer and acetone to stand and separate. The organic phase was then separated, and the acetone was removed by vacuum distillation. The organic phase was then vacuum dried at 60°C for 4 h to obtain the polyoxypropylene graft copolymer intermediate NP-10-PO. The yield of this polyoxypropylene graft copolymer was 98 g, and the average grafting degree of polyoxypropylene in the polyoxypropylene graft copolymer was 20.
[0089] S2. A substitution reaction is carried out between N,N-dimethyl-1,3-propanediamine and a polyoxypropylene graft copolymer to obtain a substituted graft copolymer with tertiary amine groups; including the following steps:
[0090] 50 g of the polyoxypropylene graft copolymer intermediate NP-10-PO was weighed and placed in a 250 mL three-necked flask. 100 mL of toluene and 10 g of N,N-dimethyl-1,3-propanediamine were added and stirred to dissolve. Then, 1.2 g of tetrabutylammonium bromide and 1.8 g of zinc oxide were added to obtain a second mixture. This second mixture was heated to 65 °C for a substitution reaction for 15 h to obtain a crude substituted graft copolymer with tertiary amine groups. Heating was stopped, and the crude substituted graft copolymer with tertiary amine groups was filtered. The filter cake was washed repeatedly with 25 mL of toluene. The filtrates were combined, and the mixture was distilled under reduced pressure to remove toluene. Finally, it was vacuum dried at 55 °C for 5 h to obtain the substituted graft copolymer intermediate NP-10-PO-N with tertiary amine groups. The yield of this substituted graft copolymer was 63 g, and the molar content of the tertiary amine groups in this substituted graft copolymer was 0.42 mmol / g.
[0091] S3. An addition reaction is performed between bisulfite, tetrabutylammonium bromide, and zinc oxide and a substituted graft copolymer having tertiary amine groups to obtain an anionic nonionic surfactant having tertiary amine and sulfonic acid groups; including the following steps:
[0092] Weigh 30g of the substituted graft copolymer NP-10-PO-N into a 100mL single-necked flask, then add 50mL of anhydrous ethanol and 20mL of deionized water and stir to dissolve, obtaining a third mixture. Then, slowly add 10mL of 40% NaHSO3 solution to the third mixture under ice bath conditions, and heat to reflux to carry out the addition reaction for 9h, to obtain the crude anionic nonionic surfactant. Heating was stopped, and the crude anionic nonionic surfactant was cooled to 50°C. Then, a 30% NaOH solution was added dropwise until the pH reached 8.5. The mixture was then filtered, and the resulting filter cake was washed with 40 mL of ethanol and 20 mL of acetone. The product was then vacuum dried at 50°C for 6 hours to obtain the finished anionic nonionic surfactant. The yield of the anionic nonionic surfactant was 36 g. The molar content of the sulfonic acid groups in the anionic nonionic surfactant was 1.05 mmol / g. The average molecular weight of the anionic nonionic surfactant was 3100. The anionic nonionic surfactant appeared as a pale yellow viscous liquid.
[0093] The amounts of tertiary amine groups (n1) and sulfonic acid groups (n2) in anionic nonionic surfactants satisfy the relationship n1:n2 = 0.42:1.05.
[0094] The amount of nonylphenol polyoxyethylene ether n3 (0.147 mol) and the amount of polyoxypropylene graft copolymer n4 (0.053 mol) satisfy the relationship: n3:n4 = 2.77:1.
[0095] The amount of sulfonic acid groups n2 in anionic nonionic surfactants and the total weight m5 of anionic nonionic surfactants satisfy the relationship: n2:m5=1.05mmol:1g.
[0096] The amount of tertiary amine group n4 in the substituted graft copolymer and the weight m4 of the substituted graft copolymer satisfy the following relationship:
[0097] n4:m4 = 0.42 mmol:1g.
[0098] Example 2
[0099] Based on the content disclosed in Example 1, the following modifications are made:
[0100] Weigh 100g of nonylphenol polyoxyethylene ether (NP-7, average degree of polymerization of polyoxyethylene EO 7, molecular weight of 500) and place it in a 500mL four-necked flask. Then add 80mL of propylene oxide and 0.6g of solid KOH to obtain the first mixture. Heat the first mixture to 130℃ to carry out the graft copolymerization reaction for 6h to obtain crude polyoxypropylene graft copolymer. Heating was then stopped, and the crude polyoxypropylene graft copolymer was cooled to 40°C. 12 mL of glacial acetic acid was added to the crude polyoxypropylene graft copolymer for neutralization. 100 mL of acetone was then added and stirred for 15 min to allow the mixture of polyoxypropylene graft copolymer and acetone to stand and separate. The organic phase was then separated, and the acetone was removed by vacuum distillation. The organic phase was then vacuum dried at 65°C for 3 h to obtain the polyoxypropylene graft copolymer intermediate NP-7-PO. The yield of this polyoxypropylene graft copolymer was 115 g, and the average grafting degree of polyoxypropylene in the polyoxypropylene graft copolymer was 15.
[0101] 45 g of the polyoxypropylene graft copolymer intermediate NP-7-PO was weighed and placed in a 250 mL three-necked flask. 90 mL of toluene and 9 g of N,N-dimethyl-1,3-propanediamine were added and stirred to dissolve. Then, 1.0 g of tetrabutylammonium bromide and 1.5 g of zinc oxide were added to obtain a second mixture. This second mixture was heated to 60 °C for a substitution reaction for 18 h to obtain a crude substituted graft copolymer with tertiary amine groups. Heating was stopped, and the crude substituted graft copolymer with tertiary amine groups was filtered. The filter cake was washed repeatedly with 30 mL of toluene. The filtrates were combined, and the mixture was distilled under reduced pressure to remove toluene. Finally, it was vacuum dried at 60 °C for 4 h to obtain the substituted graft copolymer intermediate NP-7-PO-N with tertiary amine groups. The yield of this substituted graft copolymer was 72 g, and the molar content of the tertiary amine groups in this substituted graft copolymer was 0.35 mmol / g.
[0102] 28 g of the substituted graft copolymer NP-7-PO-N was weighed and placed in a 100 mL single-necked flask. Then, 45 mL of anhydrous ethanol and 18 mL of deionized water were added and stirred to dissolve, resulting in a third mixture. Then, 9 mL of a 40% NaHSO3 solution was slowly added dropwise to the third mixture under ice bath conditions, and the mixture was heated to reflux to carry out an addition reaction for 10 h, yielding a crude anionic nonionic surfactant. Heating was stopped, and the crude anionic nonionic surfactant was cooled to 45°C. Then, a 30% NaOH solution was added dropwise until the pH reached 9.0. The mixture was then filtered, and the resulting filter cake was washed with 50 mL of ethanol and 30 mL of acetone. The product was then vacuum dried at 45°C for 8 hours to obtain the finished anionic nonionic surfactant. The yield of the anionic nonionic surfactant was 46 g. The molar content of the sulfonic acid groups in the anionic nonionic surfactant was 0.92 mmol / g. The average molecular weight of the anionic nonionic surfactant was 2700. The anionic nonionic surfactant appeared as a light brown viscous liquid.
[0103] The amount of nonylphenol polyoxyethylene ether n3 (0.200 mol) and the amount of polyoxypropylene graft copolymer n4 (0.084 mol) satisfy the relationship: n3:n4 = 2.38:1.
[0104] Example 3
[0105] Based on the content disclosed in Example 1, the following modifications are made:
[0106] Weigh 90g of nonylphenol polyoxyethylene ether (NP-10, average degree of polymerization of polyoxyethylene EO 10, molecular weight 680) and place it in a 500mL four-necked flask. Then add 45mL of propylene oxide and 0.5g of solid KOH to obtain the first mixture. Heat the first mixture to 120℃ to carry out the graft copolymerization reaction for 6h to obtain crude polyoxypropylene graft copolymer. Heating was then stopped, and the crude polyoxypropylene graft copolymer was cooled to 45°C. 10 mL of glacial acetic acid was added to the crude polyoxypropylene graft copolymer for neutralization. 120 mL of acetone was then added and stirred for 20 min to allow the mixture of polyoxypropylene graft copolymer and acetone to stand and separate. The organic phase was then separated, and the acetone was removed by vacuum distillation. The organic phase was then vacuum dried at 60°C for 4 h to obtain the polyoxypropylene graft copolymer intermediate NP-10-PO. The yield of this polyoxypropylene graft copolymer was 88 g, and the average grafting degree of polyoxypropylene in the polyoxypropylene graft copolymer was 22.
[0107] 48 g of the polyoxypropylene graft copolymer intermediate NP-10-PO was weighed and placed in a 250 mL three-necked flask. 95 mL of toluene and 9.5 g of N,N-dimethyl-1,3-propanediamine were added and stirred to dissolve. Then, 1.2 g of tetrabutylammonium bromide and 1.8 g of zinc oxide were added to obtain a second mixture. This second mixture was heated to 55 °C for a substitution reaction for 12 h to obtain a crude substituted graft copolymer with tertiary amine groups. Heating was stopped, and the crude substituted graft copolymer with tertiary amine groups was filtered. The filter cake was washed repeatedly with 25 mL of toluene. The filtrates were combined, and the mixture was distilled under reduced pressure to remove toluene. Finally, it was vacuum dried at 55 °C for 5 h to obtain the substituted graft copolymer intermediate NP-10-PO-N with tertiary amine groups. The yield of this substituted graft copolymer was 45 g, and the molar content of the tertiary amine groups in this substituted graft copolymer was 0.38 mmol / g.
[0108] Weigh 30g of the substituted graft copolymer NP-10-PO-N into a 100mL single-necked flask, then add 48mL of anhydrous ethanol and 20mL of deionized water and stir to dissolve, obtaining a third mixture. Then, slowly add 4.0mL of 40% NaHSO3 solution to the third mixture under ice bath conditions, and heat to reflux to carry out the addition reaction for 8h, to obtain the crude anionic nonionic surfactant. Heating was stopped, and the crude anionic nonionic surfactant was cooled to 50°C. Then, a 30% NaOH solution was added dropwise until the pH reached 8.5. The mixture was then filtered, and the resulting filter cake was washed with 40 mL of ethanol and 20 mL of acetone. The product was then vacuum dried at 50°C for 6 hours to obtain the finished anionic nonionic surfactant. The yield of the anionic nonionic surfactant was 28 g. The molar content of the sulfonic acid groups in the anionic nonionic surfactant was 0.95 mmol / g. The average molecular weight of the anionic nonionic surfactant was 2900. The anionic nonionic surfactant appeared as a pale yellow viscous liquid.
[0109] Comparative Example 1
[0110] An anionic nonionic reactive emulsifier obtained using the prior art (3) described in the background art.
[0111] Comparative Example 2
[0112] Based on the content disclosed in Example 1, the following modifications are made:
[0113] The graft copolymerization reaction was carried out at a temperature of 100℃ for 5 hours.
[0114] The substitution reaction was carried out at a temperature of 50°C for 10 hours.
[0115] The addition reaction takes 6 hours.
[0116] Comparative Example 3
[0117] Based on the content disclosed in Example 1, the following modifications are made:
[0118] The graft copolymerization reaction was carried out at a temperature of 140℃ for 10 hours.
[0119] The substitution reaction was carried out at a temperature of 75℃ for 24 hours.
[0120] The addition reaction takes 12 hours.
[0121] Relevant experimental and effect data:
[0122] The molecular structures of the products obtained in the examples and comparative examples were tested, and the results are shown in Table 1.
[0123] Table 1. Molecular structures of the products obtained from the examples and comparative examples.
[0124]
[0125] As shown in Table 1, the method for preparing an anionic nonionic surfactant provided in this application can use nonylphenol polyoxyethylene ether surfactants with different degrees of polymerization of polyoxyethylene as starting materials. Through optimization of process parameters for graft copolymerization, substitution reaction, and addition reaction, anionic nonionic surfactants with excellent hydrophobic and hydrophilic properties can be obtained. In Example 1, NP-10 was used as the raw material, and the grafting degree of PO was higher, which made the final anionic nonionic surfactant more hydrophobic and more suitable for emulsifying heavy oil. In Example 2, NP-7 was used as the raw material, and the grafting degree of PO was relatively lower, resulting in a higher HLB value and better water solubility of the anionic nonionic surfactant, which is more suitable for reducing interfacial tension. In addition, the average molecular weight and ionic group content of the products in these examples are slightly different, and can be selected according to actual application requirements.
[0126] The application of Example 1 to actual heavy oil emulsification includes the following specific steps:
[0127] A 0.3% (w / w) anionic nonionic surfactant was dissolved in simulated formation water (mineralization 15000 mg / L) and stirred at room temperature to obtain a surfactant solution. Then, formation heavy oil (crude oil viscosity 2000 mPa·s, 25℃) was mixed with the surfactant solution at a volume ratio of 1:3 and stirred for 30 min at a stirring rate of 2000 r / min. Simultaneously, an artificial core with an average porosity of 25% and a permeability of 2000 mD was selected. The artificial core was first saturated with crude oil to a saturation level of 65%, and then a 1.5 PV surfactant solution was injected to conduct a displacement test.
[0128] The results show that the anionic nonionic surfactant obtained by this preparation method has better heavy oil emulsification performance and stronger rock wetting modification ability. When the addition amount is 0.3%, the viscosity of heavy oil after emulsification is reduced to less than 15% of the original viscosity, and the emulsion has a stability period of more than 30 days at 75℃, which can improve the heavy oil recovery rate by more than 10%.
[0129] In summary, the present application provides a method for preparing anionic nonionic surfactants. This method achieves fine adjustment of the molecular structure of the anionic nonionic surfactant through graft copolymerization, substitution, and addition reactions. Furthermore, by adjusting the number of tertiary amine groups and sulfonic acid groups in the anionic nonionic surfactant, the molecular structure of the anionic nonionic surfactant can be further adjusted, thereby improving the accuracy of molecular structure regulation during the preparation of the anionic nonionic surfactant.
[0130] In addition, the present application provides a method for preparing anionic nonionic surfactants. The raw materials for this preparation method are widely available, and nonylphenol polyoxyethylene ether with an ideal EO / PO ratio is specifically selected as the initiator, which makes the synthesis route of this preparation method simpler and more efficient.
[0131] In addition, the method for preparing an anionic nonionic surfactant provided in this application embodiment can amination and sulfonation of nonylphenol polyoxyethylene ether under mild conditions, and retain the polyether chain structure to the maximum extent, so that the molecular weight of the anionic nonionic surfactant has more uniform and more controllable characteristics.
[0132] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed in this application.
Claims
1. A process for the preparation of an anionic-nonionic surfactant, characterized in that, The preparation method includes: Nonylphenol polyoxyethylene ether and propylene oxide were grafted and copolymerized under alkaline conditions to obtain a polyoxypropylene graft copolymer. The N,N-dimethyl-1,3-propanediamine and the polyoxypropylene graft copolymer were subjected to a substitution reaction to obtain a substituted graft copolymer with tertiary amine groups. The addition reaction of bisulfite, tetrabutylammonium bromide and zinc oxide with the substituted graft copolymer having tertiary amine groups yields an anionic nonionic surfactant having tertiary amine groups and sulfonic acid groups. The amount of tertiary amine group n1 in the anionic nonionic surfactant and the amount of sulfonic acid group n2 in the anionic nonionic surfactant satisfy the relationship n1:n2=(0.2:1.0):(2.0:1.0).
2. The production method according to claim 1, characterized by, The graft copolymerization reaction is carried out at a temperature of 120℃ to 130℃ for 6 hours to 8 hours; and / or The substitution reaction is carried out at a temperature of 55°C to 65°C for a duration of 12 h to 18 h; and / or The addition reaction takes 8 to 10 hours.
3. The preparation method according to claim 1, characterized in that, The weight m1 of the nonylphenol polyoxyethylene ether and the volume V1 of the propylene oxide satisfy the following relationship: m1:V1=(80~120):(40~60), where if the unit of m1 is g, then the unit of V1 is mL.
4. The preparation method according to claim 1, characterized in that, The weight m2 of the N,N-dimethyl-1,3-propanediamine and the weight m3 of the polyoxypropylene graft copolymer satisfy the following relationship: m2:m3=(9~11):(45~55).
5. The preparation method according to claim 1, characterized in that, The volume V2 of the bisulfite and the weight m4 of the substituted graft copolymer satisfy the following relationship: V2:m4=(9~11):(28~32), where if the unit of V2 is mL, then the unit of m4 is g; the mass concentration of the bisulfite is ≥40%.
6. The preparation method according to claim 1, characterized in that, The amount of nonylphenol polyoxyethylene ether n3 and the amount of polyoxypropylene graft copolymer n4 satisfy the following relationship: n3:n4=(0.5:1)~(3.0:1).
7. The preparation method according to claim 1, characterized in that, The amount of sulfonic acid group n2 in the anionic-nonionic surfactant and the total weight m5 of the anionic-nonionic surfactant satisfy the following relationship: n2:m5=(0.5:1)~(2.0:1), where if the unit of n2 is mmol, then the unit of m5 is g.
8. The preparation method according to claim 1, characterized in that, The amount of tertiary amine group n4 in the substituted graft copolymer and the weight m4 of the substituted graft copolymer satisfy the following relationship: n4:m4=(0.3:1)~(0.5:1), where if the unit of n4 is mmol, then the unit of m4 is g.
9. An anionic nonionic surfactant, characterized in that, The anionic nonionic surfactant is prepared by the preparation method according to any one of claims 1 to 8, and the molecular structure of the anionic nonionic surfactant is shown in Formula 1. RO-(CH2CH2O)x-[CH2CH(CH3)O]y-CH2CH(CH3)OCH2CH[CH2N(CH3)CH2SO3Na]CH2OH, Formula 1, In Formula 1, R is a nonylphenol group; x is the number of repeating units in polyethylene oxide, and y is the number of repeating units in polypropylene oxide. x and y satisfy the relationship: x + y = 20 ~ 100.
10. The anionic nonionic surfactant according to claim 9, characterized in that, The anionic nonionic surfactant comprises a nonylphenol hydrophobic segment and a polyether hydrophilic segment, wherein the mass m5 of the nonylphenol hydrophobic segment and the mass m6 of the polyether hydrophilic segment satisfy the relationship: m5:m6=(1:2)~(1:10).