Corrosion inhibitor composition

Abstract

The invention discloses a corrosion inhibitor composition which is composed of a compound shown in a formula 1, a compound shown in a formula 2 and water. According to the total mass of the corrosion inhibitor composition as 100%, the content of the compound shown in the formula 1 is 15 wt%-35 wt%, and the content of the compound shown in the formula 2 is 5 wt%-20 wt%. The temperature-resistant corrosion inhibitor composition can obviously reduce the corrosion rate of metal and reduce loss caused by corrosion, can be widely applied to the fields of oilfield water injection, oil extraction, gathering and transportation and the like, protects oil-water well shafts, pipelines and equipment, and effectively relieves the corrosion problem. The corrosion inhibitor composition disclosed by the invention can also be applied to an industrial circulating water system and an oil refining industry.

Description

Technical Field

[0001] The invention belongs to the field of corrosion protection of metal materials, and in particular relates to a temperature-resistant corrosion inhibitor composition. Background Art

[0002] my country's oil and gas field development has entered the medium and high water content period. The corrosion problem of oil and gas production systems is becoming more and more serious, and the economic losses caused to oil and gas field production are shocking. Corrosion also interferes with the normal production of oil and gas fields. Metal equipment such as oil casing, downhole pumps, sucker rods and gathering pipes in oil and gas wells often suffer from severe corrosion, which hinders the development of oilfield technology and the improvement of oil production level. Due to severe corrosion, many mature technology is difficult to promote and apply or play the due effect. Some new processes, new technologies and new equipment are difficult to use due to corrosion problems, and some technologies increase the difficulty due to corrosion factors.

[0003] Adsorption film type corrosion inhibitors can be adsorbed on the metal surface, forming a monomolecular film in the entire anode and cathode area, changing the surface properties of the metal, thereby preventing or slowing down the corresponding electrochemical reaction. There are two groups with opposite properties in the molecules of this type of compound: lipophilic group and hydrophilic group. The molecules of these compounds are adsorbed on the metal surface with hydrophilic groups, forming a dense hydrophobic film to protect the metal surface from corrosion.

[0004] There are many types of corrosion inhibitors, and the corrosion inhibition mechanism is complex. Currently, imidazoline corrosion inhibitors are widely used. Although this type of corrosion inhibitor has good corrosion inhibition performance, it is generally poorly water-soluble, which limits its scope of application. Conventional corrosion inhibitors are difficult to effectively slow down the corrosion of wellbores and pipelines during their application in oil and gas fields. As the depth of oil and gas field mining increases, the on-site operating environment becomes more and more harsh, and there is an urgent need to develop corrosion inhibitors with excellent corrosion inhibition performance under high temperature conditions. Existing single-component corrosion inhibitors are difficult to meet the requirements, and the development of corrosion inhibitors with good synergistic effects and high temperature resistance is the main research direction of corrosion inhibitors in my country's oil and gas fields. Summary of the invention

[0005] In order to solve the above problems, the present invention provides a corrosion inhibitor composition.

[0006] The corrosion inhibitor composition of the present invention is composed of a compound represented by Formula 1, a compound represented by Formula 2, and water; based on the total mass of the corrosion inhibitor composition being 100%, the content of the compound represented by Formula 1 is 15wt%-35wt%, preferably 20wt%-30wt%; the content of the compound represented by Formula 2 is 5wt%-20wt%, preferably 10wt%-15wt%;

[0007]

[0008] Wherein, the group R1 in formula 1 is C 4-28 Alkyl, preferably C12-18 normal alkyl; R2 and R3 are each independently selected from CH3, C2H5, C3H7 or C4H9, preferably C2H5; X is Cl or Br;

[0009] In Formula 2, m is any integer selected from 4 to 12; one of R4 and R5 is a hydroxyl group, and the other is R6, R7 are independently selected from C 12-18 Alkyl, C 2-18 alkenyl, C containing at least one oxygen atom 2-18 The alkyl group is preferably n-dodecyl, n-tetradecyl, n-hexadecyl or n-octadecyl.

[0010] According to one embodiment of the present invention, the preparation method of the compound represented by Formula 1 comprises: weighing a dialkyl secondary amine, a hydrohalic acid, epichlorohydrin and a solvent in proportion, adding them into a reaction device and stirring the reaction to obtain an intermediate product; and taking the intermediate product, adjusting the pH value to a certain value with an acid solution, adding an alkyl dimethylamine, and stirring the reaction at a certain temperature for a certain time.

[0011] According to another embodiment of the present invention, the dialkyl secondary amine is selected from one of dimethylamine, diethylamine, N-ethylmethylamine, N-methyl-n-propylamine, N-ethyl-n-propylamine, dipropylamine, dibutylamine or N-propylbutylamine.

[0012] According to another embodiment of the present invention, the hydrohalic acid is selected from one of hydrochloric acid solution or hydrogen bromide solution.

[0013] According to another embodiment of the present invention, the solvent is selected from tap water, distilled water, ethanol, n-propanol, isopropanol or a mixture of several thereof, preferably distilled water.

[0014] According to another embodiment of the present invention, the molar ratio of the dialkyl secondary amine, the hydrogen ions in the hydrohalic acid and the epichlorohydrin is 1:1:0.95 to 1:1:1, preferably 1:1:0.98 to 1:1:1.

[0015] According to another embodiment of the present invention, the reaction temperature for generating the intermediate product is 50-70°C, preferably 60-65°C.

[0016] According to another embodiment of the present invention, the reaction time for generating the intermediate product is 2-10 hours, preferably 5-7 hours.

[0017] According to another embodiment of the present invention, the acid solution is selected from hydrochloric acid solution or hydrogen bromide solution.

[0018] According to another embodiment of the present invention, it is characterized in that the pH value is adjusted to 5.5-6.5, preferably 6.0.

[0019] According to another embodiment of the present invention, the alkyl dimethyl tertiary amine is selected from an alkyl carbon chain of C8-C 28 The alkyl dimethylamine is preferably dodecyl dimethyl tertiary amine, tetradecyl dimethyl tertiary amine, hexadecyl dimethyl tertiary amine.

[0020] According to another embodiment of the present invention, the molar ratio of the intermediate product to the alkyl dimethyl tertiary amine is 0.95:1-1:1, preferably 0.98:1 to 1:1.

[0021] According to another embodiment of the present invention, the reaction temperature of the intermediate product and the alkyl dimethyl tertiary amine is 70-100°C, preferably 80-90°C.

[0022] According to another embodiment of the present invention, the reaction time of the intermediate product and the alkyl dimethyl tertiary amine is 2-10 hours, preferably 4-6 hours.

[0023] According to another embodiment of the present invention, the method for preparing the compound of Formula 2 comprises: contacting and reacting the amino-functionalized cyclodextrin of Formula 3 with the 1,2-epoxyalkane of Formula 4 in the presence of a solvent;

[0024]

[0025] In Formula 3, m is selected from any integer of 4-12, preferably 5-7; one of R8 and R9 is -OH, and the other is -NH2;

[0026]

[0027]

[0028] In formula 4, R is selected from H, C 1-18 Alkyl, C 2-18 alkenyl, C containing at least one oxygen atom 2-18 The alkyl group is preferably n-dodecyl, n-tetradecyl, n-hexadecyl or n-octadecyl.

[0029] According to another embodiment of the present invention, the reaction solvent is selected from one or more of methanol, ethanol, isopropanol, n-butanol, water, tetrahydrofuran, dioxane, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, and ethylene glycol, preferably one of methanol-ethyl acetate, methanol-acetone, ethanol-ethyl acetate, and ethanol-acetone.

[0030] According to another embodiment of the present invention, the amino-functionalized cyclodextrin represented by Formula 3 is selected from one or more of amino-functionalized α-cyclodextrin, amino-functionalized β-cyclodextrin, and amino-functionalized γ-cyclodextrin.

[0031] According to another embodiment of the present invention, the 1,2-epoxyalkane in Formula 4 is selected from 1,2-epoxydodecane, 1,2-epoxytetradecane, 1,2-epoxyhexadecane, and 1,2-epoxyoctadecane.

[0032] According to another embodiment of the present invention, the reaction temperature is 30-100°C, preferably 60-90°C.

[0033] According to another embodiment of the present invention, the reaction time is 1 to 7 days, preferably 2 to 5 days.

[0034] Compared with the prior art, the technical solution of the present invention has the following advantages:

[0035] (1) The nitrogen and oxygen atoms in the compounds shown in Formula 1 and Formula 2 give the corrosion inhibitor good adsorption properties. The lone pairs of electrons on the nitrogen and oxygen atoms form coordination bonds with the empty d orbitals of the metal atoms, changing the activation energy of the metal surface, effectively inhibiting the anodic reaction and slowing down the metal corrosion. The long-chain alkanes as non-polar groups in the compounds shown in Formula 1 and Formula 2 will also be arranged in a directional manner on the metal surface, reducing the contact opportunity between the metal surface and the corrosive medium, and playing a role in slowing down the corrosion.

[0036] (2) The molecular structures of the compounds shown in Formula 1 and Formula 2 both contain amine groups, multiple hydroxyl groups, and long-chain alkane groups, and have good compounding properties, producing a synergistic effect, and can form a complete, dense, and firm protective film on the metal surface, showing a good corrosion inhibition effect. In addition, after the two compounds are adsorbed on the metal surface, they can also change the wettability of the metal surface and effectively slow down the metal corrosion rate.

[0037] (3) The compound shown in Formula 2 contains a cyclodextrin polysaccharide head group, which makes it highly biocompatible, easily biodegradable, and does not cause secondary pollution.

[0038] (4) The corrosion inhibitor composition has the advantages of high temperature resistance, high salt resistance, strong erosion resistance, etc., and can be used in deep wells, ultra-deep wells, environments with complex formation conditions and stringent requirements on casing performance. DETAILED DESCRIPTION

[0039] The present invention is described in detail below in conjunction with specific implementation modes.

[0040] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0041] The corrosion inhibitor composition of the present invention is composed of the compound shown in Formula 1, the compound shown in Formula 2 and water;

[0042]

[0043] Wherein, the group R1 in formula 1 is C 4-28 Alkyl, preferably C 12-18 normal alkyl; R2 and R3 are each independently selected from CH3, C2H5, C3H7 or C4H9, preferably C2H5; X is Cl or Br;

[0044] In Formula 2, m is any integer selected from 4 to 12; one of R4 and R5 is a hydroxyl group, and the other is R6, R7 are independently selected from C 12-18 Alkyl, C 2-18 alkenyl, C containing at least one oxygen atom 2-18 The alkyl group is preferably n-dodecyl, n-tetradecyl, n-hexadecyl, or n-octadecyl. Based on the total mass of the corrosion inhibitor composition as 100%, the content of the compound shown in Formula 1 is 15wt%-35wt%, preferably 20wt%-30wt%; the content of the compound shown in Formula 2 is 5wt%-20wt%, preferably 10wt%-15wt%.

[0045] The corrosion inhibitor composition of the present invention, wherein the nitrogen atoms and oxygen atoms in the compounds shown in Formula 1 and Formula 2 make the corrosion inhibitor have good adsorption properties, and the lone pairs of electrons on the nitrogen atoms and oxygen atoms form coordination bonds with the empty d orbitals of the metal atoms, which changes the activation energy of the metal surface, effectively inhibits the anodic reaction, and slows down the metal corrosion. The long-chain alkanes as non-polar groups in the compounds shown in Formula 1 and Formula 2 will also be arranged in a directional manner on the metal surface, reducing the contact opportunity between the metal surface and the corrosive medium, and playing a role in slowing down the corrosion. The molecular structures of the compounds shown in Formula 1 and Formula 2 contain groups such as amine groups, multiple hydroxyls, and long-chain alkanes, have good composite properties, produce synergistic effects, and can form a complete, dense, and firm protective film on the metal surface, showing a good corrosion inhibition effect. In addition, after the two compounds are adsorbed on the metal surface, the wettability of the metal surface can also be changed, effectively slowing down the metal corrosion rate. And the compound shown in Formula 2 contains a cyclodextrin polysaccharide head group, so that it has strong biocompatibility, is easy to biodegrade, and does not produce secondary pollution.

[0046] In an optional embodiment, the preparation method of the compound represented by Formula 1 comprises: weighing a dialkyl secondary amine, a hydrohalic acid, epichlorohydrin and a solvent in proportion, adding them into a reaction device and stirring the reaction to obtain an intermediate product; and taking the intermediate product, adjusting the pH value to a certain value with an acid solution, adding an alkyl dimethylamine, and stirring the reaction at a certain temperature for a certain time.

[0047] The dialkyl secondary amine can be selected from one of dimethylamine, diethylamine, N-ethylmethylamine, N-methyl-n-propylamine, N-ethyl-n-propylamine, dipropylamine, dibutylamine or N-propylbutylamine. The hydrohalic acid is selected from one of hydrochloric acid solution or hydrogen bromide solution. The solvent is selected from one or a mixture of tap water, distilled water, ethanol, n-propanol, isopropanol, preferably distilled water. The molar ratio of hydrogen ions to epichlorohydrin in the dialkyl secondary amine and the hydrohalic acid is 1:1:0.95 to 1:1:1, preferably 1:1:0.98 to 1:1:1. The reaction temperature for generating the intermediate product is 50-70°C, preferably 60-65°C. The reaction time for generating the intermediate product is 2-10 hours, preferably 5-7 hours.

[0048] The acid solution for adjusting the pH value is selected from hydrochloric acid solution or hydrogen bromide solution. The pH value is adjusted to 5.5-6.5, preferably 6.0. The alkyl dimethyl tertiary amine is selected from an alkyl carbon chain of C8-C 28 The intermediate product is preferably a tertiary alkyl dimethylamine, preferably dodecyl dimethyl tertiary amine, tetradecyl dimethyl tertiary amine, hexadecyl dimethyl tertiary amine. The molar ratio of the intermediate product to the tertiary alkyl dimethylamine is 0.95:1-1:1, preferably 0.98:1-1:1. The reaction temperature of the intermediate product and the tertiary alkyl dimethylamine is 70-100°C, preferably 80-90°C. The reaction time of the intermediate product and the tertiary alkyl dimethylamine is 2-10 hours, preferably 4-6 hours.

[0049] In an optional embodiment, the method for preparing the compound of Formula 2 comprises: contacting and reacting the amino-functionalized cyclodextrin of Formula 3 with the 1,2-epoxyalkane of Formula 4 in the presence of a solvent;

[0050]

[0051] In Formula 3, m is selected from any integer of 4-12, preferably 5-7; one of R8 and R9 is -OH, and the other is -NH2;

[0052]

[0053] In formula 4, R is selected from H, C 1-18 Alkyl, C 2-18 alkenyl, C containing at least one oxygen atom 2-18 The alkyl group is preferably n-dodecyl, n-tetradecyl, n-hexadecyl or n-octadecyl.

[0054] In an optional embodiment, the reaction solvent is selected from one or more of methanol, ethanol, isopropanol, n-butanol, water, tetrahydrofuran, dioxane, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, and ethylene glycol, preferably one of methanol-ethyl acetate, methanol-acetone, ethanol-ethyl acetate, and ethanol-acetone. The amino-functionalized cyclodextrin shown in formula 3 is selected from one of amino-functionalized α-cyclodextrin, amino-functionalized β-cyclodextrin, and amino-functionalized γ-cyclodextrin. The 1,2-epoxyalkane in formula 4 is selected from 1,2-epoxydodecane, 1,2-epoxytetradecane, 1,2-epoxyhexadecane, and 1,2-epoxyoctadecane. The reaction temperature is 30 to 100°C, preferably 60 to 90°C. The reaction time is 1 to 7 days, preferably 2 to 5 days.

[0055] The corrosion inhibitor composition of the present invention can be formed by any method. For example, but not limited to: adding a certain amount of the quaternary ammonium salt compound containing tertiary amine and hydroxyl shown in Formula 1, the modified compound based on amino-functionalized cyclodextrin shown in Formula 2, and water to a reaction kettle, stirring evenly, to obtain a temperature-resistant corrosion inhibitor composition. Preferably, the mixing conditions at least meet the following conditions: the temperature is 5-40°C, and the stirring time is 20-60min.

[0056] The corrosion inhibitor composition of the present invention is used for corrosion prevention in water well injection, water well acidification, oil well production, oil well acidification, pipeline gathering and transportation, and CO2 oil recovery during the development of oil and gas fields. It is also suitable for corrosion prevention applications in industrial circulating water systems and in the oil refining industry.

[0057] The inventive concept of the present invention is explained in detail below with reference to the examples. In the following examples, unless otherwise specified, all reagents used are commercially available chemical reagents, and there is no particular limitation to this.

[0058] Some of the raw materials used in the preparation examples, embodiments and comparative examples are shown in Table 1:

[0059] Table 1 Manufacturers, batch numbers and purity of some raw materials

[0060]

[0061] Preparation Example 1

[0062] The quaternary ammonium salt containing a tertiary amine and a hydroxyl group described in Formula 1, when R1 is n-dodecyl, and R2 and R3 are both ethyl, the compound is referred to as J-1. The synthesis reaction process of J-1 is as follows:

[0063]

[0064] The specific synthesis steps are as follows: put 0.2 mol of diethylamine into a 500 mL three-necked flask, stir and slowly add 100 ml of 2 mol / L hydrochloric acid solution. Then add 0.2 mol of epichlorohydrin, and the drop rate is 3-5 seconds / drop. After that, add 80 mL of distilled water. At 60 ° C, the reaction lasts for 6 hours to obtain a light yellow mixture. The pH value of the mixture is adjusted to 6.1 with hydrochloric acid. Continue to add 0.2 mol of dodecyldimethyl tertiary amine. The reaction lasts for 5 hours at 85 ° C. Use a rotary evaporator to remove the solvent in the product. Wash the solid three times with n-hexane and recrystallize it three to five times with acetone to obtain a white solid. Compound J-1 is obtained.

[0065] Preparation Example 2

[0066] The quaternary ammonium salt containing tertiary amine and hydroxyl described in formula 1, when R1 is n-hexadecyl, and R2 and R3 are both propyl, the compound is referred to as J-2. The specific synthesis steps are as follows: 0.2 mol of dipropylamine is placed in a 500 mL three-necked flask, stirred and slowly added with 100 ml of 2 mol / L hydrochloric acid solution. Then 0.2 mol of epichlorohydrin is added, and the drop rate is 3-5 seconds / drop. After that, 90 mL of distilled water is added. At 65 ° C, the reaction lasts for 5 hours to obtain a light yellow mixture. The pH value of the mixture is adjusted to 6.0 with hydrochloric acid. Continue to add 0.2 mol of hexadecyl dimethyl tertiary amine. The reaction lasts for 4 hours at 90 ° C. The solvent in the product is removed by a rotary evaporator. The solid is washed three times with n-hexane and recrystallized three to five times with acetone to obtain a white solid. Compound J-2 is obtained.

[0067] Preparation Example 3

[0068] The modified compound based on amino-functionalized cyclodextrin described in Formula 2, when m=6, R4 is When R5 is a hydroxyl group, and R6 and R7 are n-dodecyl groups, the structure shown in Formula 2 is compound Z-1.

[0069]

[0070] Compound Z-1 shown in Formula 2 was prepared based on aminated β-cyclodextrin:

[0071] Weigh 1.134 g of mono-(6-amino-6-deoxy)-β-cyclodextrin and 0.85 g of 1,2-epoxytetradecane into a reaction bottle, then add 20 mL of anhydrous ethanol and stir evenly. Stir the reaction at 75°C for 72 hours, then stop the reaction and remove the solvent by rotary evaporation. The residue is recrystallized with an ethanol / acetone mixed solvent to obtain compound Z-1.

[0072] Preparation Example 4

[0073] The modified compound based on amino-functionalized cyclodextrin described in Formula 2, when m=5, R4 is a hydroxyl group, and R5 is When R6 and R7 are n-dodecyl, the structure shown in Formula 2 is compound Z-2.

[0074] Compound Z-2 shown in Formula 2 was prepared based on aminated α-cyclodextrin:

[0075] Weigh 0.972 g of 3A-amino-3A-deoxy-(2AS,3AS)-α-cyclodextrin hydrate and 0.85 g of 1,2-epoxytetradecane into a reaction bottle, then add 20 mL of anhydrous ethanol and stir evenly. Stir the reaction at 75°C for 72 hours, then stop the reaction and remove the solvent by rotary evaporation. The residue is recrystallized with an ethanol / acetone mixed solvent to obtain compound Z-2.

[0076] Corrosion inhibitor compositions were prepared using compounds J-1, J-2, Z-1 and Z-2 prepared in Preparations 1 to 4. "Parts by weight" in the following examples means 0.5 g.

[0077] Example 1

[0078] At 30°C, 32 parts by weight of J-1, 12 parts by weight of Z-1 and 56 parts by weight of water were added to a reactor and stirred for 30 minutes to obtain a heat-resistant corrosion inhibitor composition, numbered HJ-1.

[0079] Example 2

[0080] At 15°C, 32 parts by weight of J-1, 12 parts by weight of Z-2 and 56 parts by weight of water were added to a reactor and stirred for 35 minutes to obtain a heat-resistant corrosion inhibitor composition, numbered HJ-2.

[0081] Example 3

[0082] At 20°C, 32 parts by weight of J-2, 12 parts by weight of Z-1 and 56 parts by weight of water were added to a reactor and stirred for 40 minutes to obtain a heat-resistant corrosion inhibitor composition, numbered HJ-3.

[0083] Example 4

[0084] At 25°C, 32 parts by weight of J-2, 12 parts by weight of Z-2 and 56 parts by weight of water were added to the reactor and stirred for 25 minutes to obtain a heat-resistant corrosion inhibitor composition, numbered HJ-4.

[0085] Example 5

[0086] At 20°C, 30 parts by weight of J-1, 10 parts by weight of Z-2 and 60 parts by weight of water were added to a reactor and stirred for 35 minutes to obtain a heat-resistant corrosion inhibitor composition, numbered HJ-5.

[0087] Example 6

[0088] At 15°C, 25 parts by weight of J-1, 8 parts by weight of Z-2 and 67 parts by weight of water were added to a reactor and stirred for 35 minutes to obtain a heat-resistant corrosion inhibitor composition, numbered HJ-6.

[0089] Example 7

[0090] At 25°C, 15 parts by weight of J-1, 5 parts by weight of Z-2 and 80 parts by weight of water were added to a reactor and stirred for 35 minutes to obtain a heat-resistant corrosion inhibitor composition, numbered HJ-7.

[0091] Example 8

[0092] At 25°C, 20 parts by weight of J-1, 15 parts by weight of Z-2 and 65 parts by weight of water were added to a reactor and stirred for 35 minutes to obtain a heat-resistant corrosion inhibitor composition, numbered HJ-8.

[0093] Example 9

[0094] At 25°C, 35 parts by weight of J-1, 20 parts by weight of Z-2 and 45 parts by weight of water were added to a reaction kettle and stirred for 35 minutes to obtain a heat-resistant corrosion inhibitor composition, numbered HJ-9.

[0095] Comparative Example 1

[0096] At 20° C., 44 parts by weight of J-1 and 56 parts by weight of water were added to a reactor, and the mixture was stirred for 35 minutes to obtain a corrosion inhibitor, numbered DB-1.

[0097] Comparative Example 2

[0098] At 20° C., 44 parts by weight of J-2 and 56 parts by weight of water were added to a reactor and stirred for 35 minutes to obtain a corrosion inhibitor numbered DB-2.

[0099] Comparative Example 3

[0100] At 20°C, 44 parts by weight of Z-1 and 56 parts by weight of water were added to a reaction kettle and stirred for 30 minutes to obtain a corrosion inhibitor numbered DB-3.

[0101] Comparative Example 4

[0102] At 20°C, 44 parts by weight of Z-2 and 56 parts by weight of water were added to a reactor and stirred for 30 minutes to obtain a corrosion inhibitor numbered DB-4.

[0103] Comparative Example 5

[0104] An industrial corrosion inhibitor product used on-site in an oil field, code-named DB-5.

[0105] Test Example 1

[0106] Corrosion inhibition performance evaluation: The hanging piece weight loss method is adopted, and the hanging piece specifications are 50mm×10mm×3mm. The corrosion rate under certain conditions is determined by accurately weighing the mass difference of the metal sample before and after immersion in the corrosive medium. That is, the weighed A3 steel sheet is placed in a hydrochloric acid solution with a mass fraction of 20% without and with corrosion inhibitor, and the steel sheet is taken out after soaking at 60℃ for 4 hours, immediately rinsed with water, brushed with a soft brush, blown dry with cold air, and then weighed The mass of the steel sheet is calculated to calculate the corrosion inhibition rate.

[0107] Corrosion rate v calculation formula:

[0108]

[0109] Where:

[0110] m0——the mass of the steel sheet before hanging, g;

[0111] m——the mass of the steel sheet after hanging, g;

[0112] s——Surface area of ​​steel sheet, cm 2 ;

[0113] t——experimental time, h.

[0114] Calculation formula of corrosion inhibition rate η:

[0115]

[0116] Where:

[0117] v0——Corrosion rate of steel sheet in blank experiment, g / m 2 ·h.

[0118] v——Corrosion rate of steel sheet in the test with corrosion inhibitor added, g / m 2 ·h.

[0119] When the mass fraction of different corrosion inhibitor compositions is 0.5%, the corrosion inhibition rates are shown in Table 2.

[0120] Test Example 2

[0121] Evaluation of heat resistance: The corrosion inhibitor composition was placed in an oven at 130°C, left to stand for 24 hours, then taken out and cooled. The corrosion inhibition rate of the corrosion inhibitor was tested according to the method in Test Example 1. The corrosion inhibition rate test results are shown in Table 2.

[0122] Table 2 Corrosion inhibition rate of different corrosion inhibitor compositions

[0123]

[0124] It can be seen that the corrosion inhibitor composition provided by the present invention can significantly inhibit the corrosion process and has good temperature resistance, which can reach 130°C.

[0125] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A corrosion inhibitor composition, characterized in that: Composed of the compound shown in Formula 1, the compound shown in Formula 2 and water; Wherein, the group R1 in formula 1 is C 4-28 Alkyl, preferably C 12-18 normal alkyl; R2 and R3 are each independently selected from CH3, C2H5, C3H7 or C4H9, preferably C2H5; X is Cl or Br; In Formula 2, m is selected from any integer of 4 to 12; one of R4 and R5 is a hydroxyl group, and the other is R6, R7 are independently selected from C 12-18 Alkyl, C 2-18 alkenyl, C containing at least one oxygen atom 2-18 The alkyl group is preferably n-dodecyl, n-tetradecyl, n-hexadecyl, or n-octadecyl; Based on the total mass of the corrosion inhibitor composition as 100%, the content of the compound represented by Formula 1 is 15wt%-35wt%, preferably 20wt%-30wt%; the content of the compound represented by Formula 2 is 5wt%-20wt%, preferably 10wt%-15wt%.

2. The corrosion inhibitor composition according to claim 1, characterized in that The preparation method of the compound represented by Formula 1 comprises: Weigh a dialkyl secondary amine, a hydrohalic acid, epichlorohydrin and a solvent in proportion, add them into a reaction device, stir and react to obtain an intermediate product; and Take the intermediate product, adjust the pH value to a certain value with acid solution, then add alkyl dimethylamine, and stir the reaction at a certain temperature for a certain time.

3. The corrosion inhibitor composition according to claim 2, characterized in that The dialkyl secondary amine is selected from one of dimethylamine, diethylamine, N-ethylmethylamine, N-methyl-n-propylamine, N-ethyl-n-propylamine, dipropylamine, dibutylamine or N-propylbutylamine.

4. The corrosion inhibitor composition according to claim 2, characterized in that The hydrohalic acid is selected from one of hydrochloric acid solution or hydrogen bromide solution.

5. The corrosion inhibitor composition according to claim 2, characterized in that The solvent is selected from one or a mixture of tap water, distilled water, ethanol, n-propanol, isopropanol, preferably distilled water.

6. The corrosion inhibitor composition according to claim 2, characterized in that The molar ratio of the dialkyl secondary amine, the hydrogen ions in the hydrohalic acid and the epichlorohydrin is 1:1:0.95 to 1:1:1, preferably 1:1:0.98 to 1:1:

1.

7. The corrosion inhibitor composition according to claim 2, characterized in that The reaction temperature for generating the intermediate product is 50-70°C, preferably 60-65°C.

8. The corrosion inhibitor composition according to claim 2, characterized in that The reaction time for generating the intermediate product is 2-10 hours, preferably 5-7 hours.

9. The corrosion inhibitor composition according to claim 2, characterized in that The acid solution is selected from hydrochloric acid solution or hydrogen bromide solution.

10. The corrosion inhibitor composition according to claim 2, characterized in that: The pH value is adjusted to 5.5-6.5, preferably 6.

0.

11. The corrosion inhibitor composition according to claim 2, characterized in that The alkyl dimethyl tertiary amine is selected from alkyl carbon chains of C8-C 28 The alkyl dimethylamine is preferably dodecyl dimethyl tertiary amine, tetradecyl dimethyl tertiary amine, hexadecyl dimethyl tertiary amine.

12. The corrosion inhibitor composition according to claim 2, characterized in that The molar ratio of the intermediate product to the alkyl dimethyl tertiary amine is 0.95:1-1:1, preferably 0.98:1-1:

1.

13. The corrosion inhibitor composition according to claim 2, characterized in that: The reaction temperature of the intermediate product and the alkyl dimethyl tertiary amine is 70-100°C, preferably 80-90°C.

14. The corrosion inhibitor composition according to claim 2, characterized in that: The reaction time of the intermediate product and the alkyl dimethyl tertiary amine is 2-10 hours, preferably 4-6 hours.

15. The corrosion inhibitor composition according to claim 1, characterized in that The preparation method of the compound represented by formula 2 comprises: In the presence of a solvent, the amino-functionalized cyclodextrin of Formula 3 is contacted with the 1,2-epoxyalkane of Formula 4 for reaction; In Formula 3, m is selected from any integer of 4-12, preferably 5-7; one of R8 and R9 is -OH, and the other is -NH2; In formula 4, R is selected from H, C 1-18 Alkyl, C 2-18 alkenyl, C containing at least one oxygen atom 2-18 The alkyl group is preferably n-dodecyl, n-tetradecyl, n-hexadecyl or n-octadecyl.

16. The corrosion inhibitor composition according to claim 15, characterized in that The reaction solvent is selected from one or more of methanol, ethanol, isopropanol, n-butanol, water, tetrahydrofuran, dioxane, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, and ethylene glycol, preferably one of methanol-ethyl acetate, methanol-acetone, ethanol-ethyl acetate, and ethanol-acetone.

17. The corrosion inhibitor composition according to claim 15, characterized in that The amino-functionalized cyclodextrin shown in Formula 3 is selected from one or more of amino-functionalized α-cyclodextrin, amino-functionalized β-cyclodextrin, and amino-functionalized γ-cyclodextrin.

18. The corrosion inhibitor composition according to claim 15, characterized in that The 1,2-epoxyalkane in Formula 4 is selected from 1,2-epoxydodecane, 1,2-epoxytetradecane, 1,2-epoxyhexadecane, and 1,2-epoxyoctadecane.

19. The corrosion inhibitor composition according to claim 15, characterized in that: The reaction temperature is 30 to 100°C, preferably 60 to 90°C.

20. The corrosion inhibitor composition according to claim 15, characterized in that The reaction time is 1 to 7 days, preferably 2 to 5 days.

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