A heptadecyl imidazole type efficient corrosion inhibitor, a preparation method and application thereof

Abstract

The application discloses a heptadecyl imidazole type efficient corrosion inhibitor, a preparation method and application thereof, and belongs to the technical field of corrosion inhibitors for steel in an acidic environment. The efficient corrosion inhibitor is methyl 3-(2-heptadecyl imidazole)-2-methyl propionate, and a chemical structural formula is as follows: the efficient corrosion inhibitor is prepared through an addition reaction of 2-heptadecyl imidazole and methyl methacrylate; the application has the advantages of low drug dosage, simple synthesis method, high efficiency, safety and environmental protection; the application is used in an acidic environment such as industrial pickling and oil and gas well acidification, and compared with a conventional imidazole type corrosion inhibitor, a lower drug dosage can achieve high corrosion inhibition efficiency; in particular, in a 1 M HCl solution, when the drug dosage is 300 mg / L, the corrosion inhibition efficiency on Q235 steel reaches 98.11%.

Description

Technical Field

[0001] This invention belongs to the technical field of corrosion inhibitors for steel in acidic environments, specifically relating to a heptadecanyl imidazole-based high-efficiency corrosion inhibitor, its preparation method, and its application. Background Technology

[0002] Steel, as an indispensable material in industrial production and daily life, has an extremely wide range of applications. However, ordinary steel is almost constantly corroded during use; especially in industrial processes such as pickling and oil and gas well acidizing, the acidic environment can cause severe corrosion, leading to huge economic losses and resource waste. To effectively prevent steel corrosion, a series of targeted measures can be taken, such as improving the corrosion resistance of materials, electrochemical protection, surface coating protection, the use of corrosion-resistant alloy materials, and the addition of corrosion inhibitors. Among these measures, corrosion inhibitors have become a widely adopted anti-corrosion method due to their excellent availability, high efficiency, and ease of operation. However, improper use of corrosion inhibitors can cause a series of problems, such as pitting corrosion, hydrogen embrittlement, and weight loss corrosion on the surfaces of construction equipment and oil and gas well pipes, and in severe cases, even sudden rupture of downhole pipes. Therefore, selecting appropriate corrosion inhibitors and applying them rationally in practical engineering projects such as industrial pickling and oil and gas well acidizing is particularly important. Summary of the Invention

[0003] The purpose of this invention is to provide a heptadecanyl imidazole-based high-efficiency corrosion inhibitor, its preparation method, and its application. This invention's high-efficiency corrosion inhibitor has low dosage, simple synthesis method, high efficiency, safety, and environmental friendliness. When used as a corrosion inhibitor for steel in acidic environments such as industrial pickling and oil and gas well acidizing, it achieves high corrosion inhibition efficiency with a lower dosage compared to conventional imidazole-based corrosion inhibitors.

[0004] The objective of this invention is achieved through the following technical solution:

[0005] This invention provides a heptadecimalized imidazole-based high-efficiency corrosion inhibitor, wherein the heptadecimalized imidazole-based high-efficiency corrosion inhibitor is methyl 3-(2-heptadecimalized imidazole)-2-methylpropionate, and its chemical structural formula (I) is as follows:

[0006]

[0007] This invention provides a method for preparing a heptadecimalized imidazole-based high-efficiency corrosion inhibitor, wherein the heptadecimalized imidazole-based high-efficiency corrosion inhibitor is obtained by an addition reaction of 2-heptadecimalized imidazole and methyl methacrylate.

[0008] The present invention also provides a method for preparing the heptadecanidylimidazole-based high-efficiency corrosion inhibitor, comprising the following steps:

[0009] Step 1: Weigh 2-heptadecylimidazolium powder and methyl methacrylate liquid, and add them simultaneously to a two-necked round-bottom flask equipped with a stirrer, thermometer and reflux condenser. When adding methyl methacrylate, a polymerization inhibitor should be added at the same time. Then, slowly add solvent to the reaction system to promote full contact and mixing between the reactants to form a homogeneous colorless solution A.

[0010] Step 2: Stir solution A and heat it to reflux, resulting in a pale yellow solution B. During the reflux process, adjust the reflux rate to ensure that the condensate flows smoothly back into the flask and prevents liquid from accumulating in the condenser.

[0011] Step 3: Stop heating solution B and let it cool to room temperature. Then, distill solution B under reduced pressure to obtain a pale yellow solution C. The purpose of reduced pressure distillation is to remove the solvent, unreacted methyl methacrylate and 2-heptadecylimidazole from solution B to ensure the purity of solution C.

[0012] Step 4: After vacuum distillation, solution C is cooled to room temperature and then ground in a mortar to obtain powder D, which is a heptadecanidylimidazole-based high-efficiency corrosion inhibitor.

[0013] Furthermore, the preparation method of the heptadecanidylimidazole-based high-efficiency corrosion inhibitor includes the following reaction equation:

[0014]

[0015] Furthermore, in the preparation method of the heptadecanidazole-based high-efficiency corrosion inhibitor, the mass percentage of 2-heptadecanidazole in step one is 60.11-74.81%, the mass percentage of methyl methacrylate is 24.45-39.29%, and the mass percentage of the polymerization inhibitor is 0.6-0.97%.

[0016] The polymerization inhibitor mentioned in step one is hydroquinone. The role of the polymerization inhibitor is to prevent methyl methacrylate from polymerizing at high temperatures.

[0017] The solvent mentioned in step one is ethanol. Ethanol has the advantages of strong dissolving power, easy evaporation, low price, environmental friendliness and renewability, and high safety, making it the best solvent.

[0018] Furthermore, in the preparation method of the heptadecanidylimidazole high-efficiency corrosion inhibitor, the temperature for the reflux reaction in step two is 80±1℃.

[0019] Furthermore, in the preparation method of the heptadecanidylimidazole-based high-efficiency corrosion inhibitor, the vacuum distillation in step three is carried out at 50±1℃. During the vacuum distillation reaction, the distillation conditions are strictly controlled, the vacuum degree is set at 80~100mmHg, and the distillation rate is controlled at 1~2 drops per second. The purpose of using vacuum distillation reaction is to remove the solvent and unreacted methyl methacrylate and 2-heptadecanidazole in solution B, so as to ensure the purity of solution C.

[0020] Furthermore, in the preparation method of the heptadecanidazole-based high-efficiency corrosion inhibitor, the mass percentages of 2-heptadecanidazole, methyl methacrylate, and polymerization inhibitor are 65.21%:34.14%:0.65%, resulting in a heptadecanidazole-based high-efficiency corrosion inhibitor. In a 1M HCl solution, the dosage of the heptadecanidazole-based high-efficiency corrosion inhibitor is 300 mg / L, achieving a corrosion inhibition efficiency of 98.11% for Q235 steel.

[0021] This invention provides an application of a heptadecanylimidazole-based high-efficiency corrosion inhibitor in protecting steel in acidic environments.

[0022] Furthermore, the application of protecting steel in acidic environments is used for industrial pickling with HCl solution and acidizing of oil and gas wells.

[0023] The beneficial effects of this invention are as follows:

[0024] Compared with existing corrosion inhibitors and their preparation methods, this invention has the advantages of low reagent dosage, simple synthesis method, high efficiency, safety and environmental protection of the product, and can be widely used in acidic environments such as industrial pickling and oil and gas well acidizing.

[0025] It exhibits highly efficient corrosion inhibition on steel in 1M HCl solution, and a dosage of 300 mg / L can achieve a corrosion inhibition efficiency of up to 98.11%. Attached Figure Description

[0026] Figure 1 This is a graph showing the relationship between corrosion inhibitor concentration and corrosion rate in the static weight loss experiment of Example 1;

[0027] Figure 2 This is a SEM image of Q235 steel in 1M HCl solution in Example 1;

[0028] Figure 3 The image shows the SEM test results of the corrosion inhibitor prepared in Example 1 on Q235 steel in 1M HCl solution. Detailed Implementation

[0029] The present invention will be further described below with reference to embodiments, but this is not intended to limit the present invention in any way. Any modifications or substitutions made based on the teachings of the present invention shall fall within the protection scope of the present invention.

[0030] Example 1

[0031] 1. Synthesis of corrosion inhibitors

[0032] The specific preparation steps for heptadecanidazole-based high-efficiency corrosion inhibitors are as follows:

[0033] Step 1: Accurately weigh 5.00 g of 2-heptadecylimidazole powder and add it together with 8.48 mL of methyl methacrylate liquid into a two-necked round-bottom flask equipped with a stirrer, thermometer, and reflux condenser. When adding the methyl methacrylate raw material, simultaneously add 0.65% of the polymerization inhibitor hydroquinone. Then, slowly add 80 mL of anhydrous ethanol to the reaction system as a solvent to promote sufficient contact and mixing between the reactants, forming a homogeneous colorless solution A. The mass percentages of 2-heptadecylimidazole and methyl methacrylate are 65.21%:34.14%; solution A is colorless.

[0034] Step 2: Stir solution A and heat it to 80±1℃. Reflux the reaction at this temperature for 5 hours to obtain a pale yellow solution B. Adjust the reflux rate as needed during the reflux process to ensure that the condensate flows smoothly back into the flask and avoids liquid accumulation in the condenser.

[0035] Step 3: Stop heating solution B and allow it to cool to room temperature. Then transfer solution B to a vacuum distillation apparatus and distill under vacuum at a heating temperature of 50±1℃ for 4 hours to obtain a pale yellow solution C. During the vacuum distillation reaction, the distillation conditions must be strictly controlled. The vacuum degree is set at 100 mmHg and the distillation rate is controlled at 2 drops per second.

[0036] Step 4: After vacuum distillation, the resulting solution C is cooled to room temperature and then ground in a mortar to obtain a light yellow powder D, which is a heptadecanidylimidazole-based high-efficiency corrosion inhibitor.

[0037] 2. Static weightlessness experiment

[0038] (1) According to the experimental requirements, prepare blank acidic medium and acidic medium solutions with different concentrations of corrosion inhibitors. The acidic medium is 1M HCl solution.

[0039] (2) The Q235 sample was polished step by step with 240# to 1000# metallographic water-polishing sandpaper, then degreased with acetone, rinsed with distilled water, dehydrated with anhydrous ethanol, dried with cold air by hair dryer, and placed in a desiccator for later use.

[0040] (3) Use a high-precision balance (electronic balance, precision) to measure the initial mass (W0) of the Q235 sample;

[0041] (4) The pretreated Q235 sample was suspended in a predetermined corrosive medium and kept at a constant temperature (25±3℃) for 72 hours.

[0042] (5) After soaking, the Q235 sample was removed from the corrosive medium and the corrosion products on the sample surface were removed. Then it was rinsed with distilled water and anhydrous ethanol in sequence, and finally dried with a hair dryer and placed in a drying oven for 1 hour.

[0043] (6) Use the same high-precision balance to measure the mass (Wt) of the sample after corrosion;

[0044] (7) Experimental results and calculations:

[0045] The formula for calculating the corrosion rate is shown in Equation 1:

[0046]

[0047] Where: W0 - mass of the sample before corrosion, g; Wt - mass of the sample after corrosion, g; t - immersion time, h; s - surface area of ​​the sample, cm² 2 ;

[0048] The formula for calculating corrosion inhibition efficiency is shown in Equation 2:

[0049]

[0050] In the formula: W corr - The corrosion rate of metal without the addition of corrosion inhibitors (the mass of metal corroded per unit area per unit time); - The corrosion rate of metal after adding corrosion inhibitor.

[0051] 3. Experimental Results

[0052] The relationship between the concentration of corrosion inhibitor and its corrosion inhibition efficiency is shown in the attached figure. Figure 1 As shown in the figure, the corrosion rate gradually decreases and the corrosion inhibition efficiency gradually increases with the increase of the corrosion inhibitor concentration. Table 1 shows the static weight loss test results for each embodiment. As shown in 1 and 2 of Table 1, the corrosion inhibition efficiency reached 96.94% when the corrosion inhibitor concentration was 200 mg / L, and the highest value of 98.11% was reached when the corrosion inhibitor concentration was 300 mg / L. Figure 2 , 3 The images show SEM test results of the sample in an acidic medium solution and in an acidic medium solution with the corrosion inhibitor prepared in Example 1. It can be clearly seen that after adding the corrosion inhibitor prepared in Example 1, the corrosion degree of the carbon steel surface is significantly reduced, and the accumulation of corrosion products is almost unobservable, resulting in a relatively smooth and clean surface morphology.

[0053] Example 2

[0054] 1. Synthesis of corrosion inhibitors

[0055] The specific steps for preparing a heptadecanylimidazol-based high-efficiency corrosion inhibitor are as follows:

[0056] Step 1: Accurately weigh 5.00 g of 2-heptadecylimidazole powder and add it together with 5.30 mL of methyl methacrylate liquid into a two-necked round-bottom flask equipped with a stirrer, thermometer, and reflux condenser. When adding methyl methacrylate, add 0.74% of hydroquinone as a polymerization inhibitor. Then, slowly add 80 mL of anhydrous ethanol to the reaction system as a solvent to promote full contact and mixing between the reactants, forming a homogeneous colorless solution A. The mass percentage of 2-heptadecylimidazole and methyl methacrylate is 74.81%:24.45%.

[0057] Step 2: Stir solution A and heat it to 80±1℃. Reflux the reaction at this temperature for 5 hours to obtain a pale yellow solution B.

[0058] Step 3: Stop heating solution B and let it cool to room temperature. Then transfer solution B to a vacuum distillation apparatus, set the vacuum degree to 100 mmHg, control the distillation rate at 2 drops per second, and carry out vacuum distillation at a heating temperature of 50±1℃ for 4 hours to obtain a pale yellow solution C.

[0059] Step 4: After vacuum distillation, the resulting solution C is cooled to room temperature and then ground in a mortar to obtain powder D, which is a heptadecanidylimidazole-based high-efficiency corrosion inhibitor.

[0060] 2. Static weightlessness experiment

[0061] The corrosion inhibition efficiency of the prepared corrosion inhibitor was calculated according to the static weight loss experiment settings in Example 1.

[0062] 3. Experimental Results

[0063] As shown in Tables 1, 3 and 4, the corrosion inhibitor prepared had a corrosion inhibition efficiency of 79.44% at a dosage of 300 mg / L; and when the dosage was increased to 400 mg / L, the corrosion inhibition efficiency further increased to 92.92%.

[0064] Example 3

[0065] 1. Synthesis of corrosion inhibitors

[0066] The specific steps for preparing a heptadecanylimidazol-based high-efficiency corrosion inhibitor are as follows:

[0067] Step 1: Accurately weigh 5.00 g of 2-heptadecylimidazole powder and add it together with 6.89 mL of methyl methacrylate liquid into a two-necked round-bottom flask equipped with a stirrer, thermometer, and reflux condenser. When adding methyl methacrylate, add 0.71% of hydroquinone as a polymerization inhibitor. Then, slowly add 80 mL of anhydrous ethanol to the reaction system as a solvent to promote full contact and mixing between the reactants, forming a homogeneous colorless solution A. The mass percentage of 2-heptadecylimidazole and methyl methacrylate is 69.74%:29.55%.

[0068] Step 2: Stir solution A and heat it to 80±1℃. Reflux the reaction at this temperature for 5 hours to obtain a pale yellow solution B.

[0069] Step 3: Stop heating solution B and let it cool to room temperature. Then transfer solution B to a vacuum distillation apparatus, set the vacuum degree to 100 mmHg, control the distillation rate at 2 drops per second, and carry out vacuum distillation at a heating temperature of 50±1℃ for 4 hours to obtain a pale yellow solution C.

[0070] Step 4: After vacuum distillation, the resulting solution C is cooled to room temperature and then ground in a mortar to obtain powder D, which is a heptadecanidylimidazole-based high-efficiency corrosion inhibitor.

[0071] 2. Static weightlessness experiment

[0072] The corrosion inhibition efficiency of the prepared corrosion inhibitor was calculated according to the static weight loss experiment settings in Example 1.

[0073] 3. Experimental Results

[0074] As shown in Tables 1, 5 and 6, the corrosion inhibitor prepared had a corrosion inhibition efficiency of 85.24% at a dosage of 300 mg / L; and when the dosage was increased to 400 mg / L, the corrosion inhibition efficiency further increased to 94.04%.

[0075] Example 4

[0076] 1. Synthesis of corrosion inhibitors

[0077] The specific steps for preparing a heptadecanylimidazol-based high-efficiency corrosion inhibitor are as follows:

[0078] Step 1: Accurately weigh 5.00 g of 2-heptadecylimidazole powder and add it together with 10.60 mL of methyl methacrylate liquid into a two-necked round-bottom flask equipped with a stirrer, thermometer, and reflux condenser. When adding methyl methacrylate, 0.6% of the polymerization inhibitor hydroquinone should be added simultaneously. Subsequently, slowly add 80 mL of anhydrous ethanol to the reaction system as a solvent to promote sufficient contact and mixing between the reactants, forming a homogeneous colorless solution A. The mass percentage of 2-heptadecylimidazole and methyl methacrylate is 60.11%:39.29%.

[0079] Step 2: Stir solution A and heat it to 80±1℃. Reflux the reaction at this temperature for 5 hours to obtain a pale yellow solution B.

[0080] Step 3: Stop heating solution B and let it cool to room temperature. Then transfer solution B to a vacuum distillation apparatus, set the vacuum degree to 100 mmHg, control the distillation rate at 2 drops per second, and carry out vacuum distillation at a heating temperature of 50±1℃ for 4 hours to obtain a pale yellow solution C.

[0081] Step 4: After vacuum distillation, the resulting solution C is cooled to room temperature and then ground in a mortar to obtain powder D, which is a heptadecanidylimidazole-based high-efficiency corrosion inhibitor.

[0082] 2. Static weightlessness experiment

[0083] The corrosion inhibition efficiency of the corrosion inhibitor prepared in Example 4 was calculated according to the static weight loss experiment settings in Example 1.

[0084] 3. Experimental Results

[0085] As shown in Tables 1 and 1, the corrosion inhibitor prepared at a dosage of 300 mg / L has a corrosion inhibition efficiency of 89.31%; and when the dosage is increased to 400 mg / L, the corrosion inhibition efficiency is further improved to 95.44%.

[0086] Example 5

[0087] 1. Synthesis of corrosion inhibitors

[0088] The specific steps for preparing a heptadecanylimidazol-based high-efficiency corrosion inhibitor are as follows:

[0089] Step 1: Accurately weigh 5.00 g of 2-heptadecylimidazole powder and add it together with 8.48 mL of methyl methacrylate liquid into a two-necked round-bottom flask equipped with a stirrer, thermometer, and reflux condenser. When adding methyl methacrylate, hydroquinone, a polymerization inhibitor, should be added simultaneously at 0.97% of the total raw material. Subsequently, slowly add 80 mL of anhydrous ethanol to the reaction system as a solvent to promote sufficient contact and mixing between the reactants, forming a homogeneous colorless solution A. The mass percentage of 2-heptadecylimidazole and methyl methacrylate is 65.00%:34.03%.

[0090] Step 2: Stir solution A and heat it to 80±1℃. Reflux the reaction at this temperature for 5 hours to obtain a pale yellow solution B.

[0091] Step 3: Stop heating solution B and allow it to cool to room temperature. Then transfer solution B to a vacuum distillation apparatus and distill under vacuum at a heating temperature of 50±1℃ for 4 hours to obtain a pale yellow solution C. During the vacuum distillation reaction, the distillation conditions must be strictly controlled. The vacuum degree is set at 80 mmHg and the distillation rate is controlled at 2 drops per second.

[0092] Step 4: After vacuum distillation, the resulting solution C is cooled to room temperature and then ground in a mortar to obtain powder D, which is a heptadecanidylimidazole-based high-efficiency corrosion inhibitor.

[0093] 2. Static weightlessness experiment

[0094] The corrosion inhibition efficiency of the prepared corrosion inhibitor was calculated according to the static weight loss experiment settings in Example 1.

[0095] 3. Experimental Results

[0096] As shown in Table 1, the corrosion inhibition efficiency of the prepared corrosion inhibitor is not much different from that of the corrosion inhibitor prepared in Example 1. At a dosage of 300 mg / L, the corrosion inhibition efficiency is 97.42%.

[0097] Example 6

[0098] 1. Synthesis of corrosion inhibitors

[0099] The heptadecanidylimidazole-based high-efficiency corrosion inhibitor was prepared according to the method for preparing corrosion inhibitors in Example 1.

[0100] 2. Static weightlessness experiment

[0101] Following the static weight loss experiment setup in Example 1, with a corrosion inhibitor addition of 300 mg / L and an acidic medium of 3M HCl solution, the corrosion inhibition efficiency of the prepared corrosion inhibitor was calculated.

[0102] 3. Experimental Results

[0103] As shown in Table 10, the corrosion inhibitor prepared has a corrosion inhibition efficiency of 96.97% when the dosage of the inhibitor is 300 mg / L and the acidic medium is 3M HCl solution.

[0104] Example 7

[0105] 1. Synthesis of corrosion inhibitors

[0106] The heptadecanidylimidazole-based high-efficiency corrosion inhibitor was prepared according to the method for preparing corrosion inhibitors in Example 1.

[0107] 2. Static weightlessness experiment

[0108] Following the static weight loss experiment setup in Example 1, with a corrosion inhibitor addition of 300 mg / L and an acidic medium of 6 M HCl solution, the corrosion inhibition efficiency of the prepared corrosion inhibitor was calculated.

[0109] 3. Experimental Results

[0110] As shown in Table 1, the corrosion inhibitor prepared at a dosage of 300 mg / L in an acidic medium of 6 M HCl solution has a corrosion inhibition efficiency of 97.40%.

[0111] Table 1 Results of Static Weightlessness Experiments in Examples 1-7

[0112]

[0113] As can be seen from the results of the above embodiments, the heptadecanidylimidazole high-efficiency corrosion inhibitor and its preparation method of the present invention, compared with existing corrosion inhibitors and their preparation methods, have lower dosage, simpler synthesis methods, and produce high-efficiency, safe, and environmentally friendly products. In acidic environments such as industrial pickling and oil and gas well acidizing, compared with conventional imidazole corrosion inhibitors, a lower dosage can achieve a high-efficiency corrosion inhibition and protection effect on steel. In particular, in 1M HCl solution, a dosage of 300 mg / L can achieve a corrosion inhibition efficiency of up to 98.11%.

Claims

1. A heptadecyl imidazole based high performance corrosion inhibitor characterized in that, The heptadecimal imidazole-based high-efficiency corrosion inhibitor is methyl 3-(2-heptadecimal imidazole)-2-methylpropionate, and its chemical structural formula (Ⅰ) is as follows: 。 2. A process for the preparation of the highly efficient corrosion inhibitor of heptadecyl imidazole as claimed in claim 1, characterized in that, The heptadecimalized high-efficiency corrosion inhibitor was obtained by the addition reaction of 2-heptadecylimidazol and methyl methacrylate.

3. The production method according to claim 2, wherein Includes the following steps: Step 1: Weigh 2-heptadecylimidazolium powder and methyl methacrylate liquid, and add them simultaneously to a two-necked round-bottom flask equipped with a stirrer, thermometer and reflux condenser. When adding methyl methacrylate, the polymerization inhibitor should be added at the same time. Then, the solvent is slowly added to the reaction system to promote full contact and mixing between the reactants to form a homogeneous colorless solution A. Step 2: Stir solution A and heat it to reflux, resulting in a pale yellow solution B. During the reflux process, adjust the reflux rate to ensure that the condensate flows smoothly back into the flask and prevents the liquid from accumulating in the condenser. Step 3: Stop heating solution B, let it cool to room temperature, and then distill solution B under reduced pressure to obtain a pale yellow solution C; Step 4: After vacuum distillation, solution C is cooled to room temperature and then ground in a mortar to obtain powder D, which is a heptadecanidylimidazole-based high-efficiency corrosion inhibitor.

4. The production method according to claim 2 or 3, characterized by, The reaction equation is as follows: .

5. The preparation method according to claim 3, characterized in that, The mass percentage of 2-heptadecylimidazol in step one is 60.11–74.81%, and the mass percentage of methyl methacrylate is: The polymerization inhibitor comprises 24.45% to 39.29% by mass, and the polymerization inhibitor comprises 0.6% to 0.97% by mass. The polymerization inhibitor mentioned in step one is hydroquinone; The solvent mentioned in step one is ethanol.

6. The production method according to claim 3 or 5, wherein The temperature for the reflux reaction described in step two is 80±1 ℃.

7. The production method according to claim 6, wherein The vacuum distillation described in step three is carried out at 50±1 °C. During the vacuum distillation reaction, the distillation conditions are strictly controlled, with the vacuum degree set at 80-100 mmHg and the distillation rate controlled at 1-2 drops per second.

8. The production method according to claim 5, wherein The mass percentages of 2-heptadecylimidazolium, methyl methacrylate, and polymerization inhibitor are 65.21%:34.14%:0.65%, respectively, to prepare a heptadecylimidazolium-based high-efficiency corrosion inhibitor. In a 1M HCl solution, when the dosage of the heptadecylimidazolium-based high-efficiency corrosion inhibitor is 300 mg / L, the corrosion inhibition efficiency for Q235 steel reaches 98.11%.

9. The application of the heptadecanidylimidazole-based high-efficiency corrosion inhibitor of claim 1 in protecting steel in an acidic environment.

10. The application of protecting steel in an acidic environment as described in claim 9, characterized in that, Used for industrial pickling with HCl solution and acidizing of oil and gas wells.

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