High-temperature-resistant bactericidal corrosion inhibitor as well as preparation method and application thereof

Abstract

The invention provides a high-temperature-resistant bactericidal corrosion inhibitor as well as a preparation method and application thereof. The preparation method comprises the following steps: reacting a sulfydryl carboxylic acid compound and polyethyleneimine in an organic solvent at a first temperature for a first time to obtain a system containing a first compound; and adding halogenated hydrocarbon into the system containing the first compound, reacting at a second temperature for a second time to obtain a system containing a second compound, removing the organic solvent, and drying to obtain the high-temperature-resistant bactericidal corrosion inhibitor. The high-temperature-resistant bactericidal corrosion inhibitor disclosed by the invention is prepared by the preparation method. The invention also provides an application of the high-temperature-resistant bactericidal corrosion inhibitor in microbial corrosion protection and / or chemical corrosion protection of oil and gas fields. The high-temperature-resistant bactericidal corrosion inhibitor disclosed by the invention is simple in preparation method, good in high-temperature stability and excellent in bactericidal corrosion inhibition performance.

Description

Technical Field

[0001] The present invention belongs to the technical field of oil and gas field chemical sterilization and corrosion inhibition, and particularly relates to a high-temperature resistant bactericidal corrosion inhibitor, a preparation method thereof and an application thereof. Background Art

[0002] With the acceleration of the clean and low-carbon energy transformation process, strengthening the development and utilization of unconventional natural gas resources is a strategic choice to enhance the security of natural gas supply. In unconventional gas production systems such as shale gas and tight gas, there are not only corrosive gas CO2, but also a large number of corrosive microorganisms, such as sulfate-reducing bacteria (SRB) and saprophytic bacteria (TGB). Under the synergistic corrosion effect of CO2 and bacteria, the corrosion failure problem of unconventional gas production systems is quite prominent. This seriously restricts the safe and efficient exploitation of unconventional gas. At present, compound bactericides and corrosion inhibitors are mainly used for corrosion control. On the one hand, due to the large difference between the downhole and surface environments, the highest downhole temperature can exceed 150 °C. Most compound bactericidal corrosion inhibitors contain aldehyde-ketone compounds such as glutaraldehyde and isothiazolinone. After being exposed to high downhole temperatures, they crosslink or their performance decreases, resulting in a reduced protective effect of the returned agents on the surface pipelines. Currently, most injection ports are set at the wellbore, wellhead, etc. of the production system to inject bactericidal corrosion inhibitors to fully protect the downhole, gas production pipelines and gas gathering pipelines. This leads to a large amount of agent injection, not only a substantial increase in corrosion control costs, but also the risks of environmental pollution caused by the introduction of a large amount of agents and the complex post-treatment of the agents. On the other hand, when compounding and screening bactericides and corrosion inhibitors, the two need to be compatible with each other, do not undergo chemical reactions, and do not reduce their respective bactericidal and corrosion inhibition performances. The screening evaluation and preparation process of compound agents are relatively complex. Therefore, in order to further promote the large-scale and efficient development of unconventional gas, it is necessary to develop an integrated bactericidal corrosion inhibitor with good stability under high-temperature conditions, and use the agents returned from the wellbore to control the corrosion of surface pipelines, thereby reducing the injection volume and lowering the corrosion control cost.

[0003] There are few reports on high-temperature resistant bactericidal corrosion inhibitors at present. CN104629713B discloses a high-temperature resistant corrosion inhibitor and its preparation method. Compounds such as dodecyl dimethyl tertiary amine, polyethylenepolyamine, morpholine, and pyridine are used to prepare the high-temperature resistant corrosion inhibitor. Its preparation process is complex, the reaction temperature is high, and its bactericidal performance has not been reported. CN114231266A discloses a non-foaming corrosion inhibitor with bactericidal performance and its preparation method. Using benzylamine compounds as the main agent, biphenyl compounds as the compounding agent and auxiliary agent, they are mixed and stirred in a solvent to obtain an anti-corrosion agent with anti-carbon dioxide and microbial corrosion performance. Although this agent has the performance of multi-purpose use, its components are numerous and the preparation process is complicated. CN105439299A discloses a preparation method of a hyperbranched polyethyleneimine copolymer water treatment agent. Using hydroxylated hyperbranched polyethyleneimine and 2-acrylamide-2-methylpropanesulfonic acid as monomers, the hyperbranched polyethyleneimine copolymer water treatment agent is prepared under microwave conditions. This treatment agent has good scale inhibition, corrosion inhibition and bactericidal performance. This water treatment agent is prepared by polymerization reaction, which has great limitations in the process of industrialized scale-up production and does not have high-temperature stability. CN103554491A discloses polyethyleneimine antibacterial functionalized polymers and their preparation methods. In this preparation method, after reacting guanidine substances with high molecular polyethyleneimine to obtain a guanidinized polyethyleneimine solution, an epoxide is added to obtain an antibacterial polymer solution. However, the high-temperature resistance and corrosion inhibition performance of this antibacterial functionalized polymer have not been reported.

[0004] Therefore, developing a high-temperature resistant bactericidal corrosion inhibitor is still one of the urgent problems to be solved in this field. Summary of the Invention

[0005] To solve the above technical problems, the object of the present invention is to provide a high-temperature resistant bactericidal corrosion inhibitor, its preparation method and application. Aiming at the main control factors of corrosion in unconventional gas production systems and the problems existing in the prior art, by grafting mercapto groups into the structure of polyethyleneimine and further quaternizing, its stability, bactericidal and corrosion inhibition performance are enhanced. The preparation method of the high-temperature resistant bactericidal corrosion inhibitor of the present invention is simple, has good high-temperature stability, and has excellent bactericidal and corrosion inhibition performance.

[0006] To achieve the above object, the first aspect of the present invention provides a preparation method of a high-temperature resistant bactericidal corrosion inhibitor, which includes the following steps:

[0007] (1) React a mercapto carboxylic acid compound and polyethyleneimine in an organic solvent at a first temperature for a first time to obtain a system containing a first compound;

[0008] (2) Add a halogenated hydrocarbon to the system containing the first compound, react at a second temperature for a second time to obtain a system containing a second compound, and then remove the organic solvent and dry it to obtain the high-temperature resistant bactericidal corrosion inhibitor.

[0009] In the above preparation method, preferably, the structural formula of the mercapto carboxylic acid compound is shown in formula (I):

[0010]

[0011] In formula (I), n is a natural number from 1 to 20.

[0012] In the above preparation method, preferably, the structural formula of the polyethyleneimine is shown in formula (II):

[0013]

[0014] In formula (II), x and y are respectively natural numbers from 1 to 100. More preferably, x and y are respectively natural numbers from 1 to 20.

[0015] In the above preparation method, preferably, the organic solvent includes alcohol compounds.

[0016] In the above preparation method, preferably, the first temperature is 25°C to 100°C, and the first time is 5 to 24 h.

[0017] In the above preparation method, preferably, the structural formula of the halogenated hydrocarbon is shown in formula (III):

[0018] RZ(III)

[0019] In formula (III), R is selected from one of a straight-chain or branched-chain alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a straight-chain or branched-chain alkenyl group having 2 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, an aromatic ring-containing group having 6 to 20 carbon atoms, and an aromatic heterocyclic group having 5 to 20 carbon atoms, and Z is selected from one of chlorine, bromine, and iodine.

[0020] In the above preparation method, preferably, the second temperature is 50°C to 100°C, and the second time is 3 to 24 h.

[0021] In the above preparation method, preferably, the molar ratio of the polyethyleneimine, the mercapto carboxylic acid compound, and the halogenated hydrocarbon is (1 to 5):(5 to 50):(1 to 50).

[0022] The second aspect of the present invention provides a high-temperature resistant bactericidal and corrosion inhibitor, which is prepared by the above preparation method of the high-temperature resistant bactericidal and corrosion inhibitor.

[0023] According to the specific embodiments of the present invention, preferably, the structural formula of the high-temperature resistant bactericidal and corrosion inhibitor is shown in formula (IV):

[0024]

[0025] In formula (IV), x and y are natural numbers from 1 to 100 respectively, n is a natural number from 1 to 20, R is selected from a straight-chain or branched-chain alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a straight-chain or branched-chain alkenyl group having 2 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, an aromatic ring-containing group having 6 to 20 carbon atoms, and an aromatic heterocyclic group having 5 to 20 carbon atoms, and Z is selected from chlorine, bromine, and iodine. More preferably, x and y are natural numbers from 1 to 20 respectively.

[0026] The third aspect of the present invention provides a high-temperature resistant bactericidal and corrosion inhibitor composition. Based on the total weight of the high-temperature resistant bactericidal and corrosion inhibitor composition being 100%, it includes: 20% - 100% of the above-mentioned high-temperature resistant bactericidal and corrosion inhibitor, 0 - 80% of a solvent, and 0 - 15% of an auxiliary agent.

[0027] According to the specific embodiments of the present invention, preferably, based on the total weight of the high-temperature resistant bactericidal and corrosion inhibitor composition being 100%, it includes: 30 - 80% of the above-mentioned high-temperature resistant bactericidal and corrosion inhibitor, 20 - 50% of a solvent, and 5 - 15% of an auxiliary agent.

[0028] In the above-mentioned high-temperature resistant bactericidal and corrosion inhibitor composition, preferably, the solvent includes one or a combination of several of water, alcohol compounds, amide compounds, nitrile compounds, ketone compounds, ether compounds, and aromatic compounds, etc.

[0029] In the above-mentioned high-temperature resistant bactericidal and corrosion inhibitor composition, preferably, the auxiliary agent includes one or a combination of several of thiourea, thiazole, pyridine, piperidine, quinoline, derivatives of 1,3,5-triazine, tributyl phosphate, and thiol compounds, etc.

[0030] The fourth aspect of the present invention provides the application of the above-mentioned high-temperature resistant bactericidal and corrosion inhibitor or the above-mentioned high-temperature resistant bactericidal and corrosion inhibitor composition in the protection against microbial corrosion and / or chemical corrosion in oil and gas fields.

[0031] In the above-mentioned application, preferably, the oil and gas field includes unconventional gas fields.

[0032] The present invention provides a high-temperature resistant bactericidal and corrosion inhibitor and its preparation method, as well as a high-temperature resistant bactericidal and corrosion inhibitor composition. The structure of polyethyleneimine is stable and contains abundant primary amine, secondary amine, and tertiary amine groups, but its own bactericidal and corrosion inhibition performance is low. However, the inventors of this case have found through research that mercapto groups have excellent corrosion inhibition performance. The present invention utilizes the stable structure characteristic of polyethyleneimine, grafts mercapto groups into the structure of polyethyleneimine through chemical reactions, and further quaternizes it to improve its bactericidal and corrosion inhibition performance, thereby preparing a high-temperature resistant bactericidal and corrosion inhibitor applicable to the oil and gas field industry.

[0033] The technical solution of the present invention has at least the following beneficial effects:

[0034] The present invention modifies polyethyleneimine with a mercapto carboxylic acid compound and further quaternizes it. The bactericidal, corrosion inhibition and stability performance of polyethyleneimine are enhanced through amide groups, mercapto groups and quaternization, thereby preparing a high-temperature resistant bactericidal corrosion inhibitor. The high-temperature resistant bactericidal corrosion inhibitor has the characteristic of one molecule with multiple functions. Its preparation method is simple, it has good high-temperature stability, and has excellent bactericidal and corrosion inhibition performance. The high-temperature resistant bactericidal corrosion inhibitor of the present invention is suitable for application in the protection against microbial corrosion and / or chemical corrosion of oil and gas field pipelines, and is particularly suitable for application in the control and protection of the synergistic corrosion of CO2 and bacteria in the downhole-surface gathering and transportation of unconventional gas production systems. Description of the Drawings

[0035] Figure 1 Nuclear magnetic characterization diagram of the high-temperature resistant bactericidal corrosion inhibitor provided in Example 1.

[0036] Figure 2 Thermogravimetric curve diagram of the high-temperature resistant bactericidal corrosion inhibitor provided in Example 1.

[0037] Figure 3 Nuclear magnetic characterization diagram of the high-temperature resistant bactericidal corrosion inhibitor provided in Example 2.

[0038] Figure 4 Thermogravimetric curve diagram of the high-temperature resistant bactericidal corrosion inhibitor provided in Example 2. Detailed Embodiments

[0039] In order to have a clearer understanding of the technical features, objectives and beneficial effects of the present invention, the technical solution of the present invention will now be described in detail below, but it should not be construed as a limitation on the scope of implementation of the present invention.

[0040] According to the specific embodiments of the present invention, a first aspect of the present invention provides a preparation method of a high-temperature resistant bactericidal corrosion inhibitor, which includes the following steps:

[0041] (1) React a mercapto carboxylic acid compound and polyethyleneimine in an organic solvent at a first temperature for a first time to obtain a system containing a first compound;

[0042] (2) Add a halogenated hydrocarbon to the system containing the first compound, react at a second temperature for a second time to obtain a system containing a second compound, and then remove the organic solvent and dry it to obtain the high-temperature resistant bactericidal corrosion inhibitor.

[0043] In some embodiments, the structural formula of the mercapto carboxylic acid compound is shown in formula (I):

[0044]

[0045] In formula (I), n is a natural number from 1 to 20. Specifically, the mercapto carboxylic acid compound may include one or a combination of several of mercaptoacetic acid, 3-mercaptopropionic acid, 4-mercaptobutyric acid, 5-mercaptopentanoic acid, 6-mercaptohexanoic acid, 7-mercaptoheptanoic acid, 8-mercaptooctanoic acid, 11-mercaptoundecanoic acid, 12-mercaptododecanoic acid, 13-mercaptotridecanoic acid, 14-mercaptotetradecanoic acid, 15-mercaptopentadecanoic acid, 16-mercaptohexadecanoic acid, 17-mercaptoheptadecanoic acid, and 18-mercaptooctadecanoic acid, etc.

[0046] In some embodiments, the structural formula of the polyethyleneimine is as shown in formula (II):

[0047]

[0048] In formula (II), x and y are respectively natural numbers from 1 to 100. Preferably, x and y are respectively natural numbers from 1 to 20.

[0049] In some embodiments, the organic solvent includes alcohol compounds. Preferably, the organic solvent includes one or a combination of several of methanol, ethanol, propanol, butanol, isobutanol, and 2-methylbutanol, etc.

[0050] In some embodiments, the first temperature is 25°C to 100°C, and the first time is 5 to 24 h.

[0051] In some embodiments, the structural formula of the halogenated hydrocarbon is as shown in formula (III):

[0052] RZ(III)

[0053] In formula (III), R is selected from one of a straight-chain or branched-chain alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a straight-chain or branched-chain alkenyl group having 2 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, an aromatic ring-containing group having 6 to 20 carbon atoms, and an aromatic heterocyclic group having 5 to 20 carbon atoms, and Z is selected from one of chlorine, bromine, and iodine. Preferably, the halogenated hydrocarbon includes one or a combination of several of straight-chain or branched-chain halogenated olefins having 2 to 10 carbon atoms, straight-chain or branched-chain halogenated alkanes having 1 to 10 carbon atoms, and halogenated aromatic hydrocarbons having 6 to 20 carbon atoms. Specifically, the halogenated alkane includes one or a combination of several of chloroalkane, iodoalkane, and bromoalkane, etc., the halogenated olefin includes allyl bromide and / or allyl chloride, etc., and the halogenated aromatic hydrocarbon includes benzyl chloride and / or benzyl bromide, etc.

[0054] In some embodiments, the second temperature is 50°C to 100°C, and the second time is 3 to 24 h.

[0055] In some embodiments, the molar ratio of the polyethyleneimine, the mercapto carboxylic acid compound and the halogenated hydrocarbon is (1 to 5):(5 to 50):(1 to 50).

[0056] In some embodiments, the organic solvent is removed by rotary evaporation.

[0057] In some embodiments, the drying is vacuum drying, the drying temperature is 50°C to 60°C, and the drying time is 24 to 48 h.

[0058] According to the specific embodiments of the present invention, preferably, the preparation method of the high-temperature resistant bactericidal corrosion inhibitor includes the following steps:

[0059] (1) The mercapto carboxylic acid compound is added dropwise to the polyethyleneimine dissolved in an appropriate amount of organic solvent, and after reacting at 25°C to 100°C for 5 to 24 h, a system containing a first compound is obtained;

[0060] (2) A halogenated hydrocarbon is added to the system containing the first compound, and after reacting at 50°C to 100°C for 3 to 24 h, a system containing a second compound is obtained. The organic solvent is removed by rotary evaporation, and after drying, the high-temperature resistant bactericidal corrosion inhibitor is obtained.

[0061] According to the specific embodiments of the present invention, the reaction process of the preparation method of the high-temperature resistant bactericidal corrosion inhibitor is as follows:

[0062]

[0063] According to the specific embodiments of the present invention, in a second aspect, the present invention provides a high-temperature resistant bactericidal corrosion inhibitor, which is prepared by the above-mentioned preparation method of the high-temperature resistant bactericidal corrosion inhibitor.

[0064] According to the specific embodiments of the present invention, preferably, the structural formula of the high-temperature resistant bactericidal corrosion inhibitor is as shown in formula (IV):

[0065]

[0066] In formula (IV), x and y are natural numbers from 1 to 100 respectively, n is a natural number from 1 to 20, R is selected from a straight-chain or branched-chain alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a straight-chain or branched-chain alkenyl group having 2 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, an aromatic ring-containing group having 6 to 20 carbon atoms, and an aromatic heterocyclic group having 5 to 20 carbon atoms, and Z is selected from one of chlorine, bromine, and iodine. More preferably, x and y are natural numbers from 1 to 20 respectively.

[0067] According to a specific embodiment of the present invention, in a third aspect, the present invention provides a high-temperature resistant bactericidal and corrosion inhibitor composition. Based on the total weight of the high-temperature resistant bactericidal and corrosion inhibitor composition being 100%, it includes: 20% - 100% of the above-mentioned high-temperature resistant bactericidal and corrosion inhibitor, 0 - 80% of a solvent, and 0 - 15% of an auxiliary agent.

[0068] According to a specific embodiment of the present invention, preferably, based on the total weight of the high-temperature resistant bactericidal and corrosion inhibitor composition being 100%, it includes: 30 - 80% of the high-temperature resistant bactericidal and corrosion inhibitor, 20 - 50% of a solvent, and 5 - 15% of an auxiliary agent.

[0069] In some embodiments, the solvent includes one or a combination of several of water, alcohol compounds, amide compounds, nitrile compounds, ketone compounds, ether compounds, aromatic compounds, etc. Among them, the alcohol compounds include, but are not limited to, one or a combination of several of methanol, ethanol, propanol, butanol, isobutanol, 2-methylbutanol, etc.

[0070] In some embodiments, the auxiliary agent includes one or a combination of several of thiourea, thiazole, pyridine, piperidine, quinoline, derivatives of 1,3,5-triazine, tributyl phosphate, mercaptan compounds, etc.

[0071] According to a specific embodiment of the present invention, the high-temperature resistant bactericidal and corrosion inhibitor composition can be prepared by mixing the high-temperature resistant bactericidal and corrosion inhibitor with a solvent and an auxiliary agent.

[0072] According to a specific embodiment of the present invention, in a fourth aspect, the present invention provides the application of the above-mentioned high-temperature resistant bactericidal and corrosion inhibitor or the above-mentioned high-temperature resistant bactericidal and corrosion inhibitor composition in the protection against microbial corrosion and / or chemical corrosion in oil and gas fields.

[0073] In some embodiments, the oil and gas field includes unconventional gas fields. Specifically, the application is: the application of the high-temperature resistant bactericidal and corrosion inhibitor or the high-temperature resistant bactericidal and corrosion inhibitor composition in controlling and protecting the synergistic corrosion of CO2 and bacteria in the downhole - surface gathering and transportation pipelines of the unconventional gas production system.

[0074] The technical solutions of the present invention are specifically described below through examples and comparative examples. However, the present invention is not limited to these examples, and of course, various deformations can be carried out within the scope of the key points of the present invention.

[0075] It should be noted that in the following examples, comparative examples, and test examples, for operations that do not indicate conditions, they are all carried out according to conventional conditions or conditions recommended by the manufacturer. For raw materials that do not indicate the manufacturer and specifications, they are all conventional products that can be obtained through commercial purchase.

[0076] Example 1

[0077] Dissolve 0.04 mol of polyethyleneimine in 30 mL of ethanol, and then dropwise add 0.2 mol of mercaptoacetic acid. React at 70 °C for 12 h; then add 0.2 mol of allyl bromide and react at 70 °C for 10 h; then rotary evaporate to remove ethanol and vacuum dry at 50 °C for 48 h to obtain a high-temperature resistant bactericidal corrosion inhibitor, denoted as S1.

[0078] The structural formula of the polyethyleneimine used is as follows:

[0079]

[0080] Among them, x is a natural number from 1 to 6, and y is a natural number from 1 to 6.

[0081] The molecular weight of this polyethyleneimine is 600.

[0082] The structure of the high-temperature resistant bactericidal corrosion inhibitor in this example is as follows:

[0083]

[0084] Among them, x is a natural number from 1 to 6, and y is a natural number from 1 to 6.

[0085] Perform nuclear magnetic resonance analysis on the high-temperature resistant bactericidal corrosion inhibitor in this example, as Figure 1 shown, the result is: 1 HNMR(DMSO,400MHz)δ(ppm):1.04 - 1.08(t,-CH2-CH2-),1.81((s,-SH),2.62 - 2.80(d,-N(-C=O)-CH2-),2.99 - 3.16(m,-CH2-CH2-(-CH2-)N + (-CH2-)-,3.42 - 3.47(m,-(-CH2-)N + (-CH2-)-CH2-CH=CH2,-CH2-SH),4.89(s,-CH=CH2).

[0086] Perform thermogravimetric analysis on the high-temperature resistant bactericidal corrosion inhibitor in this example, and the obtained thermogravimetric curve is as Figure 2 shown. It can be found from Figure 2 that the main weight loss temperatures of this substance are 200.0 °C and 360.7 °C.

[0087] Example 2

[0088] Dissolve 0.04 mol of polyethyleneimine in 30 mL of ethanol, then dropwise add 0.2 mol of mercaptoacetic acid and react at 70 °C for 12 h; then add 0.1 mol of benzyl chloride and react at 70 °C for 10 h; then rotary evaporate to remove ethanol and vacuum dry at 50 °C for 48 h to obtain a high-temperature resistant bactericidal corrosion inhibitor, denoted as S2.

[0089] The structural formula of the polyethyleneimine used is as follows:

[0090]

[0091] Among them, x is a natural number from 1 to 6, and y is a natural number from 1 to 6.

[0092] The molecular weight of this polyethyleneimine is 600.

[0093] The structure of the high-temperature resistant bactericidal corrosion inhibitor of this example is as follows:

[0094]

[0095] Among them, x is a natural number from 1 to 6, and y is a natural number from 1 to 6.

[0096] Perform nuclear magnetic resonance analysis on the high-temperature resistant bactericidal corrosion inhibitor of this example, as Figure 3 shown, the results are: 1 HNMR(DMSO,400MHz)δ(ppm):1.04 - 1.08(t,-CH2-CH2-),1.82((s,-SH),2.51 - 2.76(m,-N(-C=O)-CH2-),2.97 - 3.10(m,-CH2-CH2-(-CH2-)N + (-CH2-)-,3.42 - 3.45(m,(-CH2-)N + (-CH2-)-CH2-CH2-NH-),3.74 - 3.78(m,-CH2-CH=CH-),7.20 - 7.31(M,-CH=CH-).

[0097] Perform thermogravimetric analysis on the high-temperature resistant bactericidal corrosion inhibitor of this example, and the thermogravimetric curve obtained is as Figure 4 shown, from Figure 4 it can be found that the main weight loss temperatures of this substance are 200.0 °C and 330.0 °C.

[0098] Example 3

[0099] Dissolve 0.02 mol of polyethyleneimine in 30 mL of ethanol, then dropwise add 1 mol of mercaptoacetic acid and react at 25 °C for 5 h; then add 1 mol of benzyl chloride and react at 100 °C for 24 h; then rotary evaporate to remove ethanol and vacuum dry at 50 °C for 48 h to obtain a high-temperature resistant bactericidal corrosion inhibitor, denoted as S3.

[0100] The structural formula of the polyethyleneimine used is:

[0101]

[0102] Among them, x is a natural number from 1 to 6, and y is a natural number from 1 to 6.

[0103] The molecular weight of this polyethyleneimine is 600.

[0104] The structure of the high-temperature resistant bactericidal corrosion inhibitor in this example is as follows:

[0105]

[0106] Among them, x is a natural number from 1 to 6, and y is a natural number from 1 to 6.

[0107] Example 4

[0108] Dissolve 0.04 mol of polyethyleneimine in 30 mL of ethanol, then dropwise add 0.2 mol of mercaptoacetic acid and react at 70 °C for 12 h; then add 0.2 mol of bromobutane and react at 70 °C for 10 h; then rotary evaporate to remove ethanol and vacuum dry at 50 °C for 48 h to obtain a high-temperature resistant bactericidal corrosion inhibitor, denoted as S4.

[0109] The structural formula of the polyethyleneimine used is:

[0110]

[0111] Among them, x is a natural number from 1 to 3, and y is a natural number from 1 to 3.

[0112] The molecular weight of this polyethyleneimine is 300.

[0113] The structure of the high-temperature resistant bactericidal corrosion inhibitor in this example is as follows:

[0114]

[0115] Among them, x is a natural number from 1 to 3, and y is a natural number from 1 to 3.

[0116] Example 5

[0117] Dissolve 0.04 mol of polyethyleneimine in 30 mL of ethanol, then dropwise add 0.2 mol of mercaptoacetic acid and react at 70 °C for 12 h; then add 0.2 mol of allyl bromide and react at 70 °C for 10 h; then rotary evaporate to remove ethanol and vacuum dry at 50 °C for 48 h to obtain a high-temperature resistant bactericidal corrosion inhibitor; then add isopropanol as a solvent to obtain a high-temperature resistant bactericidal corrosion inhibitor composition. Based on the total weight of the high-temperature resistant bactericidal corrosion inhibitor composition being 100%, the content of the high-temperature resistant bactericidal corrosion inhibitor is 80% and the content of isopropanol is 20%. This high-temperature resistant bactericidal corrosion inhibitor composition is denoted as S5.

[0118] Among them, the polyethyleneimine used is the same as that in Example 1.

[0119] Example 6

[0120] Dissolve 0.04 mol of polyethyleneimine in 30 mL of ethanol, then dropwise add 0.2 mol of mercaptoacetic acid and react at 70 °C for 12 h; then add 0.2 mol of allyl bromide and react at 70 °C for 10 h; then rotary evaporate to remove ethanol and vacuum dry at 50 °C for 48 h to obtain a high-temperature resistant bactericidal corrosion inhibitor; then add

[0121] thiourea as an auxiliary agent to obtain a high-temperature resistant bactericidal corrosion inhibitor composition. Based on the total weight of the high-temperature resistant bactericidal corrosion inhibitor composition being 100%, the content of the high-temperature resistant bactericidal corrosion inhibitor is 75%, the content of isopropanol is 20%, and the content of thiourea is 5%. This high-temperature resistant bactericidal corrosion inhibitor composition is denoted as S6.

[0122] Among them, the polyethyleneimine used is the same as that in Example 1.

[0123] Comparative Example 1

[0124] Dissolve 0.04 mol of polyethyleneimine in 30 mL of ethanol, then dropwise add 0.2 mol of mercaptoacetic acid and react at 70 °C for 12 h; then rotary evaporate to remove ethanol and vacuum dry at 50 °C for 48 h to obtain a bactericidal corrosion inhibitor, denoted as D1.

[0125] Among them, the polyethyleneimine used is the same as that in Example 1.

[0126] Comparative Example 2

[0127] Dissolve 0.02 mol of polyethyleneimine in 30 mL of ethanol, then dropwise add 1 mol of mercaptoacetic acid and react at 25 °C for 5 h; then rotary evaporate to remove ethanol and vacuum dry at 50 °C for 48 h to obtain a bactericidal corrosion inhibitor, denoted as D2.

[0128] Among them, the polyethyleneimine used is the same as that in Example 3.

[0129] Comparative Example 3

[0130] 0.04 mol of polyethyleneimine was dissolved in 30 mL of ethanol, and 0.2 mol of propylene bromide was added, and the mixture was reacted at 70° C. for 10 h. The ethanol was then removed by rotary evaporation, and the mixture was vacuum dried at 50° C. for 48 h to obtain a bactericidal corrosion inhibitor, which was recorded as D3.

[0131] The polyethyleneimine used is the same as that in Example 1.

[0132] Test Example 1

[0133] The bactericidal performance of the bactericidal corrosion inhibitors prepared in the above-mentioned embodiments and comparative examples was evaluated. The specific evaluation process is: after the bactericidal corrosion inhibitors were placed at room temperature and at 150°C for 24 hours, 100 mg / L of bactericidal corrosion inhibitor was used to carry out a bactericidal test on water samples containing SRB and TGB bacteria. The method of the bactericidal test is: add a bactericidal corrosion inhibitor (the amount added is 100 mg / L) to the water sample containing bacteria, and after culturing in an anaerobic environment at 25°C for 24 hours, refer to SY / T0532-2012 "Oilfield Injection Water Bacterial Analysis Method (Extinct Dilution Method)" to determine the bacterial content, calculate the bactericidal rate, and the results are shown in Table 1. The bacterial water sample used is the return fluid of a shale gas well. The formula for calculating the bactericidal rate is as follows:

[0134]

[0135] Where: X is the sterilization rate (%); a2 is the number of bacteria after sterilization (pieces / mL); a1 is the number of blank bacteria (pieces / mL).

[0136] Table 1

[0137]

[0138]

[0139] As can be seen from Table 1, after the bactericidal corrosion inhibitor prepared in the embodiment of the present invention is added to the return fluid of the shale gas well and placed at room temperature and at 150°C for 24 hours, its bactericidal performance is basically unchanged. At a usage amount of 100ppm, the bactericidal rate of the bactericidal corrosion inhibitor prepared in the embodiment of the present invention on SRB is 98.5% to 100%; the bactericidal rate on TGB is 100%. Therefore, the bactericidal corrosion inhibitor prepared in the embodiment of the present invention has excellent bactericidal performance, and its bactericidal effect is not affected after being placed at high temperature, and it has excellent high temperature stability.

[0140] Test Example 2

[0141] The corrosion inhibition effect of the bactericidal corrosion inhibitors prepared in the above examples and comparative examples was evaluated. The specific evaluation process was as follows: After the bactericidal corrosion inhibitors were placed at room temperature and at 150 °C for 24 h respectively, a corrosion test was carried out on a 5% NaCl water sample containing 800 ppm CO2. The use concentration of the bactericidal corrosion inhibitor was 100 mg / L, and the corrosion material was L360N. After being placed at 60 °C in an anaerobic environment for 72 h, referring to the standard SY / T 7437-2019 "Technical Requirements and Evaluation Methods for Corrosion Inhibitors for Natural Gas Gathering and Transportation", the corrosion rate was calculated, and the results are shown in Table 2. The corrosion rate calculation formula is as follows:

[0142]

[0143] In the formula: V—the uniform corrosion rate, unit: millimeter per year (mm / a); m—the weight loss of the specimen, unit: gram (g); s—the exposed area of the specimen, unit: square centimeter (cm 2 ); t—the experimental time, unit: hour (h); ρ—the relative density of the specimen, unit: gram per cubic centimeter (g / cm 3 ).

[0144] Table 2

[0145]

[0146]

[0147] As can be seen from Table 2, for the bactericidal corrosion inhibitor prepared in the example of the present invention, after being placed at room temperature and at 150 °C for 24 h, its corrosion rate is below 0.076 mm / a. Therefore, the bactericidal corrosion inhibitor prepared in the example of the present invention has excellent corrosion inhibition performance, and the high-temperature placement has no effect on its corrosion inhibition effect, and it has excellent high-temperature stability.

[0148] Obviously, the above examples of the present invention are only examples for clearly illustrating the present invention, and are not limitations on the embodiments of the present invention. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the embodiments here. Any obvious changes or modifications derived from the technical solutions of the present invention are still within the protection scope of the present invention.

Claims

1. A preparation method of a high-temperature resistant bactericidal and corrosion inhibitor, which comprises the following steps: (1) React a mercapto carboxylic acid compound and polyethyleneimine in an organic solvent at a first temperature for a first time to obtain a system containing a first compound; (2) Add a halogenated hydrocarbon to the system containing the first compound, react at a second temperature for a second time to obtain a system containing a second compound, and then remove the organic solvent and dry it to obtain the high-temperature resistant bactericidal and corrosion inhibitor.

2. The preparation method according to claim 1, wherein, The structural formula of the mercapto carboxylic acid compound is shown in formula (I): In formula (I), n is a natural number from 1 to 20.

3. The preparation method according to claim 1, wherein, The structural formula of the polyethyleneimine is shown in formula (II): In formula (II), x and y are respectively natural numbers from 1 to 100; Preferably, x and y are respectively natural numbers from 1 to 20.

4. The preparation method according to claim 1, wherein, The organic solvent includes alcohol compounds.

5. The preparation method according to claim 1, wherein The first temperature is 25°C to 100°C, and the first time is 5 to 24 h.

6. The preparation method according to claim 1, wherein The structural formula of the halogenated hydrocarbon is shown in formula (III): RZ(III) In formula (III), R is selected from one of a straight-chain or branched-chain alkyl group with 1 to 10 carbon atoms, an alkoxy group with 1 to 10 carbon atoms, a straight-chain or branched-chain alkenyl group with 2 to 10 carbon atoms, an alkylthio group with 1 to 10 carbon atoms, a cycloalkyl group with 3 to 10 carbon atoms, an aromatic ring-containing group with 6 to 20 carbon atoms, and an aromatic heterocyclic group with 5 to 20 carbon atoms, and Z is selected from one of chlorine, bromine, and iodine.

7. The preparation method according to claim 1, wherein, The second temperature is 50°C to 100°C, and the second time is 3 to 24 h.

8. The preparation method according to claim 1, wherein, The molar ratio of the polyethyleneimine, the mercapto carboxylic acid compound, and the halogenated hydrocarbon is (1 to 5):(5 to 50):(1 to 50).

9. A high-temperature resistant bactericidal and corrosion inhibitor, which is prepared by the preparation method of the high-temperature resistant bactericidal and corrosion inhibitor according to any one of claims 1-8.

10. The high-temperature resistant bactericidal corrosion inhibitor according to claim 9, wherein, The structural formula of the high-temperature resistant bactericidal and corrosion inhibitor is shown in formula (IV): In formula (IV), x and y are respectively natural numbers from 1 to 100, n is a natural number from 1 to 20, R is selected from one of a straight-chain or branched-chain alkyl group with 1 to 10 carbon atoms, an alkoxy group with 1 to 10 carbon atoms, a straight-chain or branched-chain alkenyl group with 2 to 10 carbon atoms, an alkylthio group with 1 to 10 carbon atoms, a cycloalkyl group with 3 to 10 carbon atoms, an aromatic ring-containing group with 6 to 20 carbon atoms, and an aromatic heterocyclic group with 5 to 20 carbon atoms, and Z is selected from one of chlorine, bromine, and iodine.

11. A high-temperature resistant bactericidal and corrosion inhibitor composition, based on 100% of the total weight of the high-temperature resistant bactericidal and corrosion inhibitor composition, comprises: 20% to 100% of the high-temperature resistant bactericidal and corrosion inhibitor according to claim 9 or 10, 0 to 80% of the solvent, and 0 to 15% of the auxiliary agent.

12. The high-temperature resistant bactericidal and corrosion inhibitor composition according to claim 11, wherein, Based on the total weight of the high-temperature resistant bactericidal and corrosion inhibitor composition being 100%, it includes: 30 to 80% of the high-temperature resistant bactericidal and corrosion inhibitor, 20 to 50% of the solvent, and 5 to 15% of the auxiliary agent.

13. The high-temperature resistant bactericidal and corrosion inhibitor composition according to claim 11, wherein, The solvent includes one or a combination of several of water, alcohol compounds, amide compounds, nitrile compounds, ketone compounds, ether compounds, and aromatic compounds.

14. The high-temperature resistant bactericidal and corrosion inhibitor composition according to claim 11, wherein, The auxiliary agent includes one or a combination of several of thiourea, thiazole, pyridine, piperidine, quinoline, 1,3,5-triazine and its derivatives, tributyl phosphate, and thiol compounds.

15. Use of the high-temperature resistant bactericidal corrosion inhibitor according to claim 9 or 10 or the high-temperature resistant bactericidal corrosion inhibitor composition according to any one of claims 11-14 in the protection against microbial corrosion and / or chemical corrosion in oil and gas fields; Preferably, the oil and gas fields include unconventional gas fields.

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