High-temperature acidification corrosion inhibitor for oil field as well as preparation method and application of high-temperature acidification corrosion inhibitor

Abstract

The invention relates to the technical field of corrosion inhibitors, and discloses a high-temperature acidizing corrosion inhibitor for an oil field and a preparation method and application thereof.The high-temperature acidizing corrosion inhibitor is prepared from (S)-1-amino-3-chloro-2-propanol hydrochloride, aldehyde compounds such as terephthalaldehyde, succinic anhydride, quinoline and the like through Schiff base, anhydride esterification and quaternization reaction, and the high-temperature acidizing corrosion inhibitor for the oil field is prepared. The novel high-temperature acidizing corrosion inhibitor for the oil field is prepared. The corrosion inhibitor provided by the invention contains a plurality of betaine groups, and can form strong interaction such as coordination and complexation on the steel sheet, so that the corrosion inhibitor can be well attached to the surface of the steel sheet to form a layer of stable organic micromolecule hydrophobic membrane, the contact between corrosion inhibition media such as hydrochloric acid and the surface of the steel sheet is inhibited, and an excellent corrosion inhibition effect is achieved. And the corrosion inhibitor contains a plurality of benzene rings, biphenyl, quinoline and other structures, has good thermal stability, and has good practical application in the aspects of corrosion prevention and corrosion inhibition of oilfield exploitation, oil pipes of high-temperature wells and other equipment.

Description

Technical Field

[0001] The invention relates to the technical field of corrosion inhibitors, in particular to a high-temperature acidizing corrosion inhibitor for oil fields and a preparation method and application thereof. Background Art

[0002] During the production of oil and gas wells, the use of fracturing and acidizing technology is an effective way to increase oil and gas production. During the fracturing and acidizing construction process, a large amount of acid is injected, which will cause corrosion of metal pipes in oil and gas wells and downhole metal equipment. In order to reduce the corrosion of acid on metal equipment in oil and gas wells, it is necessary to add corrosion inhibitors to the fracturing acid.

[0003] The current acid corrosion inhibitors for oil fields mainly include imidazolines, triazoles, quaternary ammonium salts, etc. Among them, betaine corrosion inhibitors are a kind of amphoteric surfactants with excellent performance, which have good corrosion protection and corrosion inhibition, and are widely used in oil field exploitation, metal corrosion protection, etc. Patent CN111137991 B discloses a corrosion inhibitor and scale inhibitor bactericide and its application, which is composed of betaine-type amphoteric surfactants, hexadecyl dimethyl (2-sulfite) ethyl ammonium and lignin derivatives, and has good corrosion inhibition, scale removal and antibacterial properties. However, the corrosion inhibitor and scale inhibitor bactericide of this patent does not show good high temperature resistance, and cannot meet the practical application of corrosion inhibitors in high temperature oil reservoir exploitation and other aspects. Summary of the invention

[0004] The technical problem solved by the invention is to provide a high temperature acidizing corrosion inhibitor for oil fields which has good temperature resistance and high anticorrosion and corrosion inhibition performance.

[0005] Technical solution: A high temperature acidizing corrosion inhibitor for oil fields, comprising the following structural formula;

[0006]

[0007] Furthermore, the preparation method of the high temperature acidizing corrosion inhibitor for oil fields comprises:

[0008] (1) Add ethanol, (S)-1-amino-3-chloro-2-propanol hydrochloride, and sodium hydroxide to a container, stir, then add an aldehyde compound, stir and react at 50-65° C. for 6-10 hours, add water to dilute, extract with ethyl acetate, dry the organic phase with anhydrous sodium sulfate, filter, and evaporate under reduced pressure. Dissolve the product in ethanol and recrystallize to obtain intermediate A.

[0009] (2) Add tetrahydrofuran, intermediate A, succinic anhydride, and 4-dimethylaminopyridine to a container, stir and react at 40-50° C. for 18-24 hours, add water and sodium hydroxide, adjust the pH to 9-10, add saturated sodium chloride solution, extract with ethyl acetate, dry the organic phase with anhydrous sodium sulfate, filter and evaporate under reduced pressure, dissolve the product in ethanol aqueous solution, and recrystallize to obtain intermediate B.

[0010] (3) Add ethanol, intermediate B, and quinoline into a container, stir and react at 75-80° C. for 36-48 hours, and distill under reduced pressure. Dissolve the product in ethanol aqueous solution and recrystallize to obtain a high-temperature acidification corrosion inhibitor for oil fields.

[0011] Furthermore, in (1), the molar ratio of (S)-1-amino-3-chloro-2-propanol hydrochloride, sodium hydroxide, and aldehyde compound is (2-3.3):(2-3.3):1.

[0012] Furthermore, the aldehyde compound is terephthalaldehyde, 4,4'-biphenyldicarboxaldehyde or trimesic acid.

[0013] Furthermore, in (2), the molar ratio of intermediate A, succinic anhydride, and 4-dimethylaminopyridine is 1:(2.4-3.6):(0.12-0.16).

[0014] Furthermore, in (3), the molar ratio of intermediate B to quinoline is 1:(2.4-3.6).

[0015] Furthermore, the application of high temperature acidizing corrosion inhibitor for oil fields in oil field corrosion prevention and inhibition.

[0016] The technical effect of the present invention is as follows: the present invention uses (S)-1-amino-3-chloro-2-propanol hydrochloride, aldehyde compounds such as terephthalaldehyde, succinic anhydride, quinoline and the like as raw materials, and undergoes Schiff base, acid anhydride esterification and quaternization reactions to prepare a novel high-temperature acidification corrosion inhibitor for oil fields.

[0017] The corrosion inhibitor of the present invention contains multiple betaine groups, which can form strong coordination and complex interactions with steel sheets, so that the corrosion inhibitor is well attached to the surface of the steel sheet, forming a stable organic small molecule hydrophobic film, inhibiting the contact between hydrochloric acid and other corrosion-inhibiting media and the surface of the steel sheet, and playing an excellent corrosion-inhibiting role. In addition, the corrosion inhibitor contains multiple benzene rings, biphenyls, quinoline and other structures, has good thermal stability, and the corrosion inhibitor will not undergo thermal decomposition at high temperatures, so that the corrosion inhibitor still maintains good structural stability, the corrosion inhibition efficiency decreases very little, and the corrosion resistance and corrosion inhibition performance are excellent. It has good practical applications in the corrosion resistance and corrosion inhibition of equipment such as oil field exploitation and oil pipes in high-temperature wells. DETAILED DESCRIPTION

[0018] In order to make the technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be described in further detail below.

[0019] Example 1

[0020] (1) Add 30 mL of ethanol, 20 mmol of (S)-1-amino-3-chloro-2-propanol hydrochloride (CAS No. 34839-13-9), and 20 mmol of sodium hydroxide to a container, stir, add 10 mmol of terephthalaldehyde, stir and react at 65°C for 6 hours, add water to dilute, extract with ethyl acetate, dry the organic phase with anhydrous sodium sulfate, filter and distill under reduced pressure, dissolve the product in ethanol, and recrystallize to obtain intermediate A. The reaction formula is:

[0021]

[0022] (2) Add 40 mL of tetrahydrofuran, 10 mmol of intermediate A, 24 mmol of succinic anhydride, and 1.2 mmol of 4-dimethylaminopyridine to a container, stir and react at 40°C for 24 hours, add 20 mL of water and sodium hydroxide, adjust the pH to 9, add saturated sodium chloride solution, extract with ethyl acetate, dry the organic phase with anhydrous sodium sulfate, filter and distill under reduced pressure, dissolve the product in ethanol aqueous solution, and recrystallize to obtain intermediate B. The reaction formula is:

[0023]

[0024] (3) Add 20 mL of ethanol, 20 mmol of intermediate B, and 48 mmol of quinoline to the container, stir and react at 75°C for 48 hours, and distill under reduced pressure. Dissolve the product in ethanol aqueous solution and recrystallize to obtain a high-temperature acidification corrosion inhibitor for oil fields. The reaction formula is:

[0025]

[0026] Example 2

[0027] (1) Add 40 mL of ethanol, 20 mmol of (S)-1-amino-3-chloro-2-propanol hydrochloride, and 20 mmol of sodium hydroxide to a container, stir, add 10 mmol of 4,4'-biphenyldicarboxaldehyde, stir and react at 60°C for 8 hours, add water to dilute, extract with ethyl acetate, dry the organic phase with anhydrous sodium sulfate, filter and distill under reduced pressure, dissolve the product in ethanol, and recrystallize to obtain intermediate A. The structural formula is:

[0028]

[0029] (2) Add 60 mL of tetrahydrofuran, 10 mmol of intermediate A, 24 mmol of succinic anhydride, and 1.2 mmol of 4-dimethylaminopyridine to a container, stir and react at 50°C for 24 hours, add 20 mL of water and sodium hydroxide, adjust the pH to 9, add saturated sodium chloride solution, extract with ethyl acetate, dry the organic phase with anhydrous sodium sulfate, filter and distill under reduced pressure, dissolve the product in ethanol aqueous solution, and recrystallize to obtain intermediate B. The structural formula is:

[0030] (3) Add 30 mL of ethanol, 20 mmol of intermediate B, and 48 mmol of quinoline to the container, stir and react at 80°C for 36 hours, and distill under reduced pressure. Dissolve the product in ethanol aqueous solution and recrystallize to obtain a high-temperature acidification corrosion inhibitor for oil fields. The structural formula is:

[0031] Example 3

[0032] (1) Add 40 mL of ethanol, 33 mmol of (S)-1-amino-3-chloro-2-propanol hydrochloride, and 33 mmol of sodium hydroxide to a container, stir, add 10 mmol of trimesaldehyde, stir and react at 50°C for 10 hours, add water to dilute, extract with ethyl acetate, dry the organic phase with anhydrous sodium sulfate, filter and distill under reduced pressure, dissolve the product in ethanol, and recrystallize to obtain intermediate A. The structural formula is:

[0033]

[0034] (2) Add 60 mL of tetrahydrofuran, 10 mmol of intermediate A, 36 mmol of succinic anhydride, and 1.6 mmol of 4-dimethylaminopyridine to a container, stir and react at 50°C for 24 hours, add 20 mL of water and sodium hydroxide, adjust the pH to 10, add saturated sodium chloride solution, extract with ethyl acetate, dry the organic phase with anhydrous sodium sulfate, filter and distill under reduced pressure, dissolve the product in ethanol aqueous solution, and recrystallize to obtain intermediate B. The structural formula is:

[0035] (3) Add 30 mL of ethanol, 20 mmol of intermediate B, and 72 mmol of quinoline to the container, stir and react at 80°C for 48 hours, and distill under reduced pressure. Dissolve the product in ethanol aqueous solution and recrystallize to obtain a high-temperature acidification corrosion inhibitor for oil fields. The structural formula is:

[0036] Comparative Example 1 Intermediate B prepared in Example 1 As a corrosion inhibitor.

[0037] Comparative Example 2 Intermediate B prepared in Example 2 As a corrosion inhibitor.

[0038] Comparative Example 3 Intermediate B prepared in Example 3 As a corrosion inhibitor.

[0039] Comparative Example 4

[0040] (1) Add 30 mL of ethanol, 10 mmol of (S)-1-amino-3-chloro-2-propanol hydrochloride, and 20 mmol of sodium hydroxide to a container, stir, add 10 mmol of phthalaldehyde, stir and react at 65°C for 6 hours, add water to dilute, extract with ethyl acetate, dry the organic phase with anhydrous sodium sulfate, filter and distill under reduced pressure, dissolve the product in ethanol, and recrystallize to obtain intermediate A. The structural formula is:

[0041]

[0042] (2) Add 40 mL of tetrahydrofuran, 10 mmol of intermediate A, 12 mmol of succinic anhydride, and 1.2 mmol of 4-dimethylaminopyridine to a container, stir and react at 40°C for 24 hours, add 20 mL of water and sodium hydroxide, adjust the pH to 9, add saturated sodium chloride solution, extract with ethyl acetate, dry the organic phase with anhydrous sodium sulfate, filter and distill under reduced pressure, dissolve the product in ethanol aqueous solution, and recrystallize to obtain intermediate B. The structural formula is:

[0043] (3) Add 20 mL of ethanol, 20 mmol of intermediate B, and 24 mmol of quinoline to the container, stir and react at 75°C for 48 hours, and distill under reduced pressure. Dissolve the product in ethanol aqueous solution and recrystallize to obtain a corrosion inhibitor. The structural formula is:

[0044] According to SY / T 5405-1996 "Test Methods and Evaluation Indicators for Acidification Corrosion Inhibitors", the corrosion resistance and corrosion inhibition performance of the corrosion inhibitor was tested. The sample was N80 steel sheet. Before the test, the N80 steel sheet was polished, cleaned, degreased, and dried. The corrosive medium was a 20% hydrochloric acid solution by mass. The mass fraction of the corrosion inhibitor in the corrosive medium was 3%. The test temperature was 25-150℃, and a condensation reflux pipe was installed during the test. After corrosion, the corrosion rate V and the corrosion inhibition efficiency n were calculated.

[0045] V = (M-M1) / (S×t); M is the initial mass of the N80 steel sample, M1 is the mass of the N80 steel sample after corrosion products are removed from the initial mass. S is the surface area of ​​the N80 steel sample. s is the corrosion time.

[0046] n = (V1-V0) / V0×100%. V1 is the corrosion rate when the corrosion inhibitor is added. V0 is the corrosion rate when no corrosion inhibitor is added.

[0047] Table 1 Corrosion inhibition efficiency test of corrosion inhibitor

[0048]

[0049] After testing, the high-temperature acidification corrosion inhibitor for oil fields prepared in Examples 1-3 has a corrosion inhibition efficiency of 92.0-99.3% at room temperature of 25°C, and a corrosion inhibition efficiency of 85.7-94.4% at a high temperature of 150°C. This is mainly because the corrosion inhibitor contains multiple betaine groups, which can form strong coordination and complex interactions with the steel sheet, have a large binding capacity, and have strong adsorption properties, so that the corrosion inhibitor is well attached to the surface of the steel sheet, forming a layer of stable organic small molecule hydrophobic film, inhibiting the contact of corrosion-inhibiting media such as hydrochloric acid with the surface of the steel sheet, and playing an excellent corrosion inhibition role. In addition, the corrosion inhibitor contains multiple benzene rings, biphenyls, quinoline and other structures, has good thermal stability, and the corrosion inhibitor will not undergo thermal decomposition at high temperatures, so that the corrosion inhibitor still maintains good structural stability, the corrosion inhibition efficiency decreases very little, and the corrosion protection and corrosion inhibition performance is excellent.

[0050] Comparative Examples 1, 2, and 3 use intermediate B as the corrosion inhibitor, which does not contain betaine groups and has poor coordination and complex interactions with the steel sheet surface. It is difficult to form a stable organic small molecule hydrophobic film on the steel sheet surface, and the corrosion inhibition efficiency is very low.

[0051] The corrosion inhibitor of Comparative Example 4 contains only one betaine group, and has poor interaction with the surface of the steel sheet in terms of coordination and complexation, and thus has low corrosion inhibition efficiency.

[0052] The above is a detailed description of an embodiment of the present invention, but the content is only a preferred embodiment of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A high temperature acidizing corrosion inhibitor for oil fields, characterized in that: The high temperature acidizing corrosion inhibitor for oil fields includes the following structural formula:

2. A method for preparing a high temperature acidizing corrosion inhibitor for oil fields as claimed in claim 1, characterized in that: The preparation method comprises: (1) Add ethanol, (S)-1-amino-3-chloro-2-propanol hydrochloride, and sodium hydroxide to a container, stir, then add an aldehyde compound, stir to react, add water to dilute, extract with ethyl acetate, and recrystallize to obtain intermediate A; (2) Add tetrahydrofuran, intermediate A, succinic anhydride, and 4-dimethylaminopyridine to a container, stir to react, add water and sodium hydroxide, adjust the pH to 9-10, add saturated sodium chloride solution, extract with ethyl acetate, and recrystallize to obtain intermediate B; (3) Add ethanol, intermediate B and quinoline into a container, stir to react, distill under reduced pressure, and recrystallize to obtain a high temperature acidification corrosion inhibitor for oil fields.

3. The method for preparing a high temperature acidizing corrosion inhibitor for oil fields according to claim 2, characterized in that: In the above (1), the molar ratio of (S)-1-amino-3-chloro-2-propanol hydrochloride, sodium hydroxide and aldehyde compound is (2-3.3):(2-3.3):

1.

4. The method for preparing a high temperature acidizing corrosion inhibitor for oil fields according to claim 3, characterized in that: The aldehyde compound is terephthalaldehyde, 4,4'-biphenyldicarboxaldehyde or trimesic acid.

5. The method for preparing a high temperature acidizing corrosion inhibitor for oil fields according to claim 2, characterized in that: In the step (1), the reaction is carried out at 50-65°C for 6-10 hours.

6. The method for preparing a high temperature acidizing corrosion inhibitor for oil fields according to claim 2, characterized in that: In the above (2), the molar ratio of intermediate A, succinic anhydride and 4-dimethylaminopyridine is 1:(2.4-3.6):(0.12-0.16).

7. The method for preparing a high temperature acidizing corrosion inhibitor for oil fields according to claim 2, characterized in that: In the step (2), the reaction is carried out at 40-50°C for 18-24 hours.

8. The method for preparing a high temperature acidizing corrosion inhibitor for oil fields according to claim 2, characterized in that: In the above (3), the molar ratio of intermediate B to quinoline is 1:(2.4-3.6).

9. The method for preparing a high temperature acidizing corrosion inhibitor for oil fields according to claim 2, characterized in that: In the step (3), the reaction is carried out at 75-80°C for 36-48 hours.

10. Use of the high temperature acidizing corrosion inhibitor for oil fields obtained by the preparation method according to any one of claims 2 to 9 in oil field corrosion protection and inhibition.

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