Compound for scale and corrosion inhibitor, and scale and corrosion inhibitor

Abstract

Provided in the present invention are a compound for a scale and corrosion inhibitor, and the scale and corrosion inhibitor. The compound for the scale and corrosion inhibitor has a structure represented by formula (I).

Description

Compound for scale and corrosion inhibitor and scale and corrosion inhibitor

[0001] Cross-reference information

[0002] This application claims priority to the Chinese patent application filed with the Patent Office of China on December 27, 2023, with application number CN202311814157.3 and invention name “A compound for scale and corrosion inhibitor and scale and corrosion inhibitor”, the entire contents of which are incorporated by reference into this application. Technical Field

[0003] The present invention belongs to the field of oilfield chemical agents, and particularly relates to a novel high-temperature resistant water-soluble scale and corrosion inhibitor compound for sulfur-containing gas fields and a novel high-temperature resistant scale and corrosion inhibitor for sulfur-containing gas fields comprising the scale and corrosion inhibitor compound. Background Art

[0004] In the oil and gas production industry, the presence of components such as H2S, CO2, and inorganic salts can cause scaling, corrosion, and blockage in oil and gas field gathering and transportation pipelines and wellbores, particularly in sour gas fields. Sour gas fields present one of the harshest and most corrosive environments in oil and gas production. The highly toxic and corrosive H2S can corrode the metal materials of downhole tubing and surface collection and transportation equipment. Measures must be taken to control corrosion and scaling during oil and gas development. With the continuous advancement of oil and gas resource extraction technology, oil and gas development is advancing into deep and ultra-deep formations, with well depths and temperatures reaching new highs, making downhole corrosion control in sour gas fields difficult.

[0005] Adding corrosion and scale inhibitors is one of the most common practices, characterized by simplicity, low cost, and significant effectiveness. However, existing corrosion inhibitors often present numerous challenges when used at high temperatures: degradation due to their inherent stability decline; and desorption due to reduced adsorption between the inhibitor and the metal. The effectiveness of existing corrosion inhibitors typically decreases dramatically with increasing temperature, resulting in a general inability to meet operational requirements at high temperatures.

[0006] In summary, people currently need to study high-temperature resistant scale and corrosion inhibitors suitable for sulfur-containing gas fields. Summary of the Invention

[0007] The purpose of the present invention is to provide a scale and corrosion inhibitor that is applicable to sulfur-containing gas fields and has high-temperature resistance, and has excellent corrosion and scaling resistance at high temperatures.

[0008] In order to achieve the above object, the present invention provides a compound for scale and corrosion inhibition, which has the structure shown in Formula I:

[0009] The scale and corrosion inhibitor compound can be applied to the production of sulfur-containing gas fields, can be quickly adsorbed on the metal surface and is not easily denatured at high temperatures, and has excellent high-temperature corrosion / scaling resistance.

[0010] According to a specific embodiment of the present invention, preferably, wherein R1 is selected from one of substituted or unsubstituted alkyl and aminoalkyl; more preferably, R1 is selected from One of them.

[0011] According to a specific embodiment of the present invention, preferably, R2 is selected from one of H and substituted or unsubstituted aryl; preferably, R2 is selected from According to a specific embodiment of the present invention, preferably, R3 is selected from a substituted or unsubstituted five-membered or six-membered ring containing a heteroatom; preferably, R3 is selected from One of them.

[0012] The present invention also provides a method for preparing a scale and corrosion inhibitor, which comprises the following steps:

[0013] Mixing an aldehyde, a polyamine, a ketone, and a first polar solvent to obtain a first mixture; wherein the molar ratio of the aldehyde, the polyamine, and the ketone is 1.0-1.2:0.5:1.0-1.2; and the volume of the first polar solvent is 3-5 times the total volume of the aldehyde, the polyamine, and the ketone;

[0014] The pH of the first mixture is adjusted to 2-6, and then a first heating reaction is performed under inert gas protection, and the product obtained by the first heating reaction is subjected to a first purification treatment to remove residual reactants to obtain an intermediate product;

[0015] Mixing a second polar solvent, sodium 2-hydroxy-3-chloropropyl phosphate (HCP), and the intermediate product to obtain a second mixture; wherein the mass ratio of the second polar solvent, sodium 2-hydroxy-3-chloropropyl phosphate (HCP), and the intermediate product is 100:0.5-1:5-10;

[0016] The second mixture is subjected to a second heating reaction, and solid precipitation in the product obtained in the second heating reaction is removed, thereby preparing a scale and corrosion inhibitor.

[0017] The preparation method of the scale inhibitor and corrosion inhibitor provided by the present invention can simply and quickly prepare the scale inhibitor and corrosion inhibitor comprising the scale inhibitor and corrosion inhibitor compound having the structure shown in the above formula I.

[0018] According to a specific embodiment of the present invention, preferably, the polyamine includes at least one of ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, and pentaethylenehexamine.

[0019] According to a specific embodiment of the present invention, preferably, the aldehyde includes one of cinnamaldehyde, formaldehyde and benzaldehyde.

[0020] According to a specific embodiment of the present invention, preferably, the ketone comprises one of 2-acetylthiazole, 1-acetylimidazole and 3-acetylpyridine.

[0021] According to a specific embodiment of the present invention, preferably, the first solvent includes at least one of anhydrous ethanol, deionized water, dimethyl sulfoxide, and N,N-dimethylformamide; more preferably, the first solvent is anhydrous ethanol.

[0022] According to a specific embodiment of the present invention, preferably, the second polar solvent includes at least one of anhydrous ethanol, deionized water, dimethyl sulfoxide, and N,N-dimethylformamide.

[0023] According to a specific embodiment of the present invention, preferably, the reagent used for adjusting the pH of the first mixture is hydrochloric acid; further, based on the mass of the hydrochloric acid being 100%, the mass concentration of HCl in the hydrochloric acid is 5-20%.

[0024] According to a specific embodiment of the present invention, preferably, the temperature of the first heating reaction is 70-100°C.

[0025] According to a specific embodiment of the present invention, preferably, the first step of heating reaction time is 4-10 hours.

[0026] According to a specific embodiment of the present invention, preferably, the temperature of the second step heating reaction is 75-95°C.

[0027] According to a specific embodiment of the present invention, preferably, the second step heating reaction time is 5-24 hours.

[0028] According to a specific embodiment of the present invention, preferably, the first purification treatment of the product obtained by the first heating reaction comprises: concentrating the product obtained by the first heating reaction by rotary evaporation until the solvent is completely volatilized, and then removing the remaining reactants using a third polar solvent and an anti-solvent, wherein the volume ratio of the third polar solvent to the anti-solvent is 1:2-5;

[0029] More preferably, the temperature of rotary evaporation is 40-70°C;

[0030] More preferably, removing the remaining reactants using the third polar solvent and the anti-solvent comprises: adding the third polar solvent, then removing the solid precipitate, then adding the anti-solvent, stirring and mixing, and then extracting in an ice bath to remove the remaining reactants;

[0031] More preferably, the third polar solvent includes at least one of anhydrous ethanol, deionized water, dimethyl sulfoxide, and N,N-dimethylformamide;

[0032] More preferably, the antisolvent comprises at least one of diethyl ether, ethyl acetate, methyl acetate, and acetone;

[0033] More preferably, the ratio of the mass of the product after rotary evaporation and concentration until the solvent is completely volatilized to the mass of the third polar solvent is 1:5-15.

[0034] According to a specific embodiment of the present invention, preferably, the method further comprises:

[0035] The product obtained by removing the solid precipitate from the product obtained by the second step of the heating reaction is mixed with a fourth polar solvent and an optional auxiliary agent to prepare a scale and corrosion inhibitor;

[0036] More preferably, the fourth polar solvent includes at least one of anhydrous ethanol, deionized water, dimethyl sulfoxide, and N,N-dimethylformamide;

[0037] More preferably, the auxiliary agent includes at least one of potassium iodide, 2-methyl-3-butyn-2-ol, propynol and β-cyclodextrin;

[0038] More preferably, the mass of the polar solvent is 30% or more, based on the mass of the product obtained by removing the solid precipitate in the product obtained by the second step heating reaction being 100%;

[0039] More preferably, based on the mass of the product obtained by removing the solid precipitate in the product obtained by the second step heating reaction being 100%, the mass of the auxiliary agent is 5-15%.

[0040] The scale and corrosion inhibitor prepared by the preparation method of the scale and corrosion inhibitor provided by the present invention is water-soluble, can be applied to sulfur-containing gas fields, and has excellent high-temperature resistance and corrosion resistance / scaling resistance.

[0041] The present invention provides a scale inhibitor and corrosion inhibitor, which comprises the compound for scale inhibitor and corrosion inhibitor provided by the present invention.

[0042] According to a specific embodiment of the present invention, preferably, the scale and corrosion inhibitor further comprises a polar solvent;

[0043] More preferably, the polar solvent includes at least one of anhydrous ethanol, deionized water, dimethyl sulfoxide, and N,N-dimethylformamide;

[0044] According to a specific embodiment of the present invention, preferably, the scale and corrosion inhibitor further comprises an auxiliary agent;

[0045] More preferably, the auxiliary agent includes at least one of potassium iodide, 2-methyl-3-butyn-2-ol, propynol and β-cyclodextrin.

[0046] In a specific embodiment of the present invention, a scale inhibitor and corrosion inhibitor prepared by the preparation method of the scale inhibitor and corrosion inhibitor provided by the present invention is provided.

[0047] The scale and corrosion inhibitor provided by the present invention is water-soluble, can be applied to sulfur-containing gas fields, and has excellent high-temperature resistance and corrosion / scaling resistance.

[0048] The present invention also provides application of the scale and corrosion inhibitor in the development of sulfur-containing gas fields.

[0049] According to a specific embodiment of the present invention, preferably, the application environment temperature of the scale and corrosion inhibitor is 0-180°C.

[0050] The scale and corrosion inhibitor compound provided by the present invention has excellent water solubility, can be rapidly adsorbed onto metal surfaces, and is not easily denatured at high temperatures. The scale and corrosion inhibitor provided by the present invention, comprising the scale and corrosion inhibitor compound provided by the present invention, exhibits excellent high-temperature resistance and combined corrosion and scaling resistance, effectively protecting downhole tubing strings in sulfur-containing gas fields from electrochemical corrosion and reducing scaling. Compared to existing technologies, it has the following beneficial effects:

[0051] 1. The scale and corrosion inhibitor provided by the present invention has excellent corrosion inhibition performance and can meet the corrosion inhibition efficiency requirements at extremely low dosages. For example, in certain embodiments, under the conditions of an addition dosage of 100 ppm and a temperature of 80°C, the corrosion inhibition efficiency can still reach more than 98%.

[0052] 2. The scale and corrosion inhibitor provided by the present invention also has good corrosion inhibition performance under high temperature conditions; for example, in certain embodiments, under the conditions of an addition dosage of 1500 ppm and a high temperature of 180°C, the corrosion inhibition efficiency can still reach more than 93%.

[0053] 3. The scale and corrosion inhibitor provided by the present invention has excellent scale inhibition performance; for example, in certain embodiments, under the condition of adding 100 ppm, the scale inhibition efficiency can reach more than 98%.

[0054] 4. The scale and corrosion inhibitor provided by the present invention also has good scale inhibition performance under high temperature conditions; for example, in certain embodiments, under the conditions of an addition dosage of 1500 ppm and a high temperature of 180°C, the scale inhibition efficiency can still reach more than 81%. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] FIG1 is a Fourier transform infrared spectrum characterization diagram of the intermediate product in Example 5 of the present invention.

[0056] FIG2 is a Fourier transform infrared spectrum characterization diagram of the final product in Example 5 of the present invention.

[0057] FIG3 is a nuclear magnetic spectrum characterization diagram of the intermediate product in Example 5 of the present invention.

[0058] FIG4 is a nuclear magnetic spectrum characterization diagram of the final product in Example 5 of the present invention.

[0059] FIG5 is a thermogravimetric analysis diagram of the final product in Examples 5-8 of the present invention. DETAILED DESCRIPTION

[0060] 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 is now described in detail below, but it should not be understood as limiting the scope of implementation of the present invention.

[0061] Example 1

[0062] This embodiment provides a scale and corrosion inhibitor, the preparation method of which includes the following steps:

[0063] The reactants cinnamaldehyde, diethylenetriamine, and 1-acetylimidazole were added to a reaction vessel in a molar ratio of 1.0:0.5:1.0, and anhydrous ethanol was added in an amount three times the volume of the reactants to obtain a first mixture. The pH of the first mixture was adjusted to 2 using concentrated hydrochloric acid. Nitrogen was continuously introduced into the reaction vessel, and the first heating reaction was achieved by heating at 70°C for 4 hours. After the reaction system was cooled, the mixture was concentrated by rotary evaporation at 50°C until the solvent was completely evaporated.

[0064] Anhydrous ethanol was added to the product after rotary evaporation (the mass of anhydrous ethanol was 10 times the mass of the product after rotary evaporation and filtration), and then the solid precipitate was removed. Ethyl acetate was added (the volume ratio of anhydrous ethanol to ethyl acetate was 1:5) and stirred. After ice bath extraction, excess reactants were removed to obtain an intermediate product.

[0065] Deionized water, sodium 2-hydroxy-3-chloropropyl phosphate (HCP) and the intermediate product are mixed in a mass ratio of 100:0.5:5 to obtain a second mixture, and the second mixture is stably heated at 80° C. for 5 hours to achieve a second step heating reaction, and the solid precipitate in the solution is filtered to obtain the final product.

[0066] Deionized water accounting for 40% of the mass of the final product is added to the final product to obtain a scale and corrosion inhibitor.

[0067] In the first step of heating reaction:

[0068] In the second step of heating reaction:

[0069] The final product contains a scale and corrosion inhibitor compound having the following structural formula:

[0070] Example 2

[0071] This embodiment provides a scale and corrosion inhibitor, the preparation method of which includes the following steps:

[0072] The reactants cinnamaldehyde, tetraethylenepentamine, and 2-acetylthiazole were added to a reaction vessel in a molar ratio of 1.2:0.5:1.1, and anhydrous ethanol was added in an amount three times the volume of the reactants to obtain a first mixture. The pH of the first mixture was adjusted to 4 using concentrated hydrochloric acid. Nitrogen was continuously introduced into the reaction vessel, and the first heating reaction was achieved by heating at 80°C for 6 hours. After the reaction system was cooled, the mixture was concentrated by rotary evaporation at 50°C until the solvent was completely evaporated.

[0073] Anhydrous ethanol was added to the product after rotary evaporation (the mass of anhydrous ethanol was 10 times the mass of the product after rotary evaporation and filtration), and then the solid precipitate was removed. Ethyl acetate was added (the volume ratio of anhydrous ethanol to ethyl acetate was 1:5) and stirred. After ice bath extraction, excess reactants were removed to obtain an intermediate product.

[0074] Deionized water, sodium 2-hydroxy-3-chloropropyl phosphate (HCP) and the intermediate product are mixed in a mass ratio of 100:0.5:10 to obtain a second mixture, and the second mixture is stably heated at 80° C. for 5 hours to achieve a second step heating reaction, and the solid precipitate in the solution is filtered to obtain the final product.

[0075] 40% of the mass of the final product deionized water and 10% of potassium iodide additive were added to the final product to obtain a scale and corrosion inhibitor.

[0076] In the first step of heating reaction:

[0077] In the second step of heating reaction:

[0078] The final product contains a scale and corrosion inhibitor compound having the following structural formula:

[0079] Example 3

[0080] This embodiment provides a scale and corrosion inhibitor, the preparation method of which includes the following steps:

[0081] The reactants cinnamaldehyde, tetraethylenepentamine, and 2-acetylthiazole were added to a reaction vessel in a molar ratio of 1.0:0.5:1.0, and anhydrous ethanol was added in an amount three times the volume of the reactants to obtain a first mixture. The pH of the first mixture was adjusted to 6 using concentrated hydrochloric acid, and nitrogen was continuously introduced into the reaction vessel. The first heating reaction was achieved by heating at 80° C. for 8 hours. After the reaction system was cooled, the mixture was concentrated by rotary evaporation at 50° C. until the solvent was completely evaporated.

[0082] Anhydrous ethanol was added to the product after rotary evaporation (the mass of anhydrous ethanol was 10 times the mass of the product after rotary evaporation and filtration), and then the solid precipitate was removed. Ethyl acetate was added (the volume ratio of anhydrous ethanol to ethyl acetate was 1:5) and stirred. After ice bath extraction, excess reactants were removed to obtain an intermediate product.

[0083] Deionized water, sodium 2-hydroxy-3-chloropropyl phosphate (HCP) and the intermediate product are mixed in a mass ratio of 100:0.5:10 to obtain a second mixture, and the second mixture is stably heated at 80° C. for 5 hours to achieve a second step heating reaction, and the solid precipitate in the solution is filtered to obtain the final product.

[0084] Deionized water (40% by mass of the final product) and a propargyl alcohol additive (10% by mass) were added to the final product to obtain a scale and corrosion inhibitor.

[0085] In the first step of heating reaction:

[0086] In the second step of heating reaction:

[0087] The final product contains a scale and corrosion inhibitor compound having the following structural formula:

[0088] Example 4

[0089] This embodiment provides a scale and corrosion inhibitor, the preparation method of which includes the following steps:

[0090] The reactants cinnamaldehyde, tetraethylenepentamine, and 3-acetylpyridine were added to a reaction vessel in a molar ratio of 1.2:0.5:1.1, and anhydrous ethanol was added in an amount three times the volume of the reactants to obtain a first mixture. The pH of the first mixture was adjusted to 4 using concentrated hydrochloric acid. Nitrogen was continuously introduced into the reaction vessel, and the first heating reaction was achieved by heating at 80° C. for 6 hours. After the reaction system was cooled, the mixture was concentrated by rotary evaporation at 50° C. until the solvent was completely evaporated.

[0091] Anhydrous ethanol was added to the product after rotary evaporation (the mass of anhydrous ethanol was 10 times the mass of the product after rotary evaporation and filtration), and then the solid precipitate was removed. Ethyl acetate was added (the volume ratio of anhydrous ethanol to ethyl acetate was 1:5) and stirred. After ice bath extraction, excess reactants were removed to obtain an intermediate product.

[0092] Deionized water, sodium 2-hydroxy-3-chloropropyl phosphate (HCP) and the intermediate product are mixed in a mass ratio of 100:0.5:10 to obtain a second mixture, and the second mixture is stably heated at 90° C. for 5 hours to achieve a second step heating reaction, and the solid precipitate in the solution is filtered to obtain the final product.

[0093] Deionized water (40% by mass of the final product) and a beta-cyclodextrin additive (10%) were added to the final product to obtain a scale and corrosion inhibitor.

[0094] In the first step of heating reaction:

[0095] In the second step of heating reaction:

[0096] The final product contains a scale and corrosion inhibitor compound having the following structural formula:

[0097] Example 5

[0098] This embodiment provides a scale and corrosion inhibitor, the preparation method of which includes the following steps:

[0099] The reactants cinnamaldehyde, tetraethylenepentamine, and 2-acetylthiazole were added to a reaction vessel in a molar ratio of 1.0:0.5:1.0, and anhydrous ethanol was added in an amount three times the volume of the reactants to obtain a first mixture. The pH of the first mixture was adjusted to 4 using concentrated hydrochloric acid, nitrogen was continuously introduced into the reaction vessel, and the first heating reaction was achieved by heating at 80° C. for 6 hours. After the reaction system was cooled, the mixture was concentrated by rotary evaporation at 50° C. until the solvent was completely evaporated.

[0100] Anhydrous ethanol was added to the product after rotary evaporation (the mass of anhydrous ethanol was 10 times the mass of the product after rotary evaporation and filtration), and then the solid precipitate was removed. Ethyl acetate was added (the volume ratio of anhydrous ethanol to ethyl acetate was 1:5) and stirred, and then ice-bathed extraction was performed to remove excess reactants to obtain an intermediate product.

[0101] Deionized water, sodium 2-hydroxy-3-chloropropyl phosphate (HCP) and the intermediate product are mixed in a mass ratio of 100:0.5:10 to obtain a second mixture, and the second mixture is stably heated at 80° C. for 5 hours to achieve a second step heating reaction, and the solid precipitate in the solution is filtered to obtain the final product.

[0102] Deionized water (40% by mass of the final product) and a beta-cyclodextrin additive (10%) were added to the final product to obtain a scale and corrosion inhibitor.

[0103] In the first step of heating reaction:

[0104] In the second step of heating reaction:

[0105] The final product contains a scale and corrosion inhibitor compound having the following structural formula:

[0106] Example 6

[0107] This embodiment provides a scale and corrosion inhibitor, the preparation method of which includes the following steps:

[0108] The reactants, benzaldehyde, tetraethylenepentamine, and 2-acetylthiazole, were added to a reaction vessel in a molar ratio of 1.1:0.5:1.1, and anhydrous ethanol in an amount three times the volume of the reactants was added to obtain a first mixture. The pH of the first mixture was adjusted to 4 using concentrated hydrochloric acid. Nitrogen was continuously introduced into the reaction vessel, and the first heating reaction was achieved by heating at 75° C. for 6 hours. After the reaction system was cooled, the mixture was concentrated by evaporation at 50° C. until the solvent was completely evaporated.

[0109] Anhydrous ethanol was added to the product after rotary evaporation (the mass of anhydrous ethanol was 10 times the mass of the product after rotary evaporation and filtration), and then the solid precipitate was removed. Ethyl acetate was added (the volume ratio of anhydrous ethanol to ethyl acetate was 1:3) and stirred. After ice bath extraction, excess reactants were removed to obtain an intermediate product.

[0110] Deionized water, sodium 2-hydroxy-3-chloropropyl phosphate (HCP) and the intermediate product are mixed in a mass ratio of 100:0.5:10 to obtain a second mixture, and the second mixture is stably heated at 80° C. for 5 hours to achieve a second step heating reaction, and the solid precipitate in the solution is filtered to obtain the final product.

[0111] 40% of the mass of the final product of deionized water, 5% of propargyl alcohol additive and 5% of beta-cyclodextrin additive were added to the final product to obtain a scale inhibitor and corrosion inhibitor.

[0112] In the first step of heating reaction:

[0113] In the second step of heating reaction:

[0114] The final product contains a scale and corrosion inhibitor compound having the following structural formula:

[0115] Example 7

[0116] This embodiment provides a scale and corrosion inhibitor, the preparation method of which includes the following steps:

[0117] The reactants, formaldehyde solution (a formaldehyde aqueous solution with a formaldehyde mass concentration of 37%), tetraethylenepentamine, and 2-acetylthiazole, were added to a reaction vessel at a molar ratio of formaldehyde, tetraethylenepentamine, and 2-acetylthiazole of 1.0:0.5:1.0. Anhydrous ethanol was added in an amount three times the volume of the reactants to obtain a first mixture. The pH of the first mixture was adjusted to 4 using concentrated hydrochloric acid. Nitrogen was continuously introduced into the reaction vessel, and the first heating reaction was achieved by heating at 90° C. for 6 hours. After the reaction system was cooled, the mixture was concentrated by rotary evaporation at 50° C. until the solvent was completely evaporated.

[0118] Anhydrous ethanol was added to the product after rotary evaporation (the mass of anhydrous ethanol was 10 times the mass of the product after rotary evaporation and filtration), and then the solid precipitate was removed. Ethyl acetate was added (the volume ratio of anhydrous ethanol to ethyl acetate was 1:5) and stirred. After ice bath extraction, excess reactants were removed to obtain an intermediate product.

[0119] Deionized water, sodium 2-hydroxy-3-chloropropyl phosphate (HCP) and the intermediate product are mixed in a mass ratio of 100:1:10 to obtain a second mixture, the second mixture is stably heated at 80° C. for 5 hours to achieve a second step heating reaction, and the solid precipitate in the solution is filtered to obtain the final product.

[0120] 40% of the mass of the final product of deionized water, 5% of a potassium iodide auxiliary agent and 5% of a beta-cyclodextrin auxiliary agent were added to the final product to obtain a scale inhibitor and corrosion inhibitor.

[0121] In the first step of heating reaction:

[0122] In the second step of heating reaction:

[0123] The final product contains a scale and corrosion inhibitor compound having the following structural formula:

[0124] Example 8

[0125] This embodiment provides a scale and corrosion inhibitor, the preparation method of which includes the following steps:

[0126] The reactants cinnamaldehyde, tetraethylenepentamine, and 2-acetylthiazole were added to a reaction vessel in a molar ratio of 1.2:0.5:1.2, and anhydrous ethanol was added in an amount three times the volume of the reactants to obtain a first mixture. The pH of the first mixture was adjusted to 6 using concentrated hydrochloric acid. Nitrogen was continuously introduced into the reaction vessel, and the first heating reaction was achieved by heating at 80° C. for 10 hours. After the reaction system was cooled, the mixture was concentrated by rotary evaporation at 50° C. until the solvent was completely evaporated.

[0127] Dimethyl sulfoxide (DMSO) was added to the product after rotary evaporation (the mass of anhydrous ethanol was 10 times the mass of the product after rotary evaporation and filtration), and then the solid precipitate was removed. Ethyl acetate (the volume ratio of DMSO to ethyl acetate was 1:5) was added, stirred, and then ice-bathed to remove excess reactants to obtain an intermediate product.

[0128] Dimethyl sulfoxide, sodium 2-hydroxy-3-chloropropyl phosphate (HCP) and the intermediate product are mixed in a mass ratio of 100:0.5:10 to obtain a second mixture, and the second mixture is stably heated at 80° C. for 5 hours to achieve a second step heating reaction, and the solid precipitate in the solution is filtered to obtain the final product.

[0129] 40% of the mass of the final product of dimethyl sulfoxide, 5% of a potassium iodide auxiliary agent and 5% of a beta-cyclodextrin auxiliary agent were added to the final product to obtain a scale inhibitor and corrosion inhibitor.

[0130] In the first step of heating reaction:

[0131] In the second step of heating reaction:

[0132] The final product contains a scale and corrosion inhibitor compound having the following structural formula:

[0133] Example 9

[0134] This embodiment provides a scale and corrosion inhibitor, the preparation method of which includes the following steps:

[0135] The reactants cinnamaldehyde, tetraethylenepentamine, and 2-acetylthiazole were added to a reaction vessel in a molar ratio of 1.2:0.5:1.2, and anhydrous ethanol was added in an amount three times the volume of the reactants to obtain a first mixture. The pH of the first mixture was adjusted to 6 using concentrated hydrochloric acid. Nitrogen was continuously introduced into the reaction vessel, and the first heating reaction was achieved by heating at 80° C. for 10 hours. After the reaction system was cooled, the mixture was concentrated by rotary evaporation at 50° C. until the solvent was completely evaporated.

[0136] Dimethyl sulfoxide (DMSO) was added to the product after rotary evaporation (the mass of anhydrous ethanol was 10 times the mass of the product after rotary evaporation and filtration), and then the solid precipitate was removed. Ethyl acetate (the volume ratio of DMSO to ethyl acetate was 1:5) was added, stirred, and then ice-bathed to remove excess reactants to obtain an intermediate product.

[0137] Dimethyl sulfoxide, sodium 2-hydroxy-3-chloropropyl phosphate (HCP) and the intermediate product are mixed in a mass ratio of 100:0.5:10 to obtain a second mixture, and the second mixture is stably heated at 80° C. for 5 hours to achieve a second step heating reaction, and the solid precipitate in the solution is filtered to obtain the final product.

[0138] 40% of the mass of the final product of dimethyl sulfoxide, 5% of 2-methyl-3-butyn-2-ol auxiliary agent and 5% of beta-cyclodextrin auxiliary agent were added to the final product to obtain a scale inhibitor and corrosion inhibitor.

[0139] In the first step of heating reaction:

[0140] In the second step of heating reaction:

[0141] The final product contains a scale and corrosion inhibitor compound having the following structural formula:

[0142] Product performance testing:

[0143] Test Example 1:

[0144] The scale and corrosion inhibitors provided in Examples 1 to 8 were tested for their corrosion inhibition performance at normal pressure.

[0145] The specific test process is as follows: the scale and corrosion inhibitors provided in Examples 1 to 8 are subjected to corrosion tests on water samples containing H2S and CO2 respectively. The corrosion experiment process is carried out with reference to Section 3 "Method for Determination of Static Corrosion Rate and Inhibition Rate at Normal Pressure" of China's Petroleum Industry Standard SY / T 5273-2000 "Evaluation Method for Corrosion Inhibitors for Oilfield Produced Water". Among them, the material of the test piece is the BG110SS seamless steel pipe material used for wellbore oil pipes, and the corrosion test medium is an aqueous solution containing 50000ppm NaCl, 1000ppm H2S and 300ppm CO2. The concentration of the scale and corrosion inhibitor is 100ppm (based on the total mass of the corrosion test medium as 100%), the temperature environment is 80°C, and the oxygen environment is anaerobic. After 72 hours of corrosion under the above conditions, the corrosion rate r is determined according to the mass difference of the test piece before and after the test. corr and corrosion inhibition rate η.

[0146] Among them, the annual corrosion rate r corr Determined by the following formula:

[0147] Where: r corr is the uniform corrosion rate in millimeters per year (mm / a); Δm is the weight loss of the coupon in grams (g); s is the exposed area of ​​the coupon in square centimeters (cm 2); t is the experimental time, in hours (h); ρ is the relative density of the coupon, in grams per cubic centimeter (g / cm 3 ).

[0148] Among them, the corrosion inhibition rate η is determined by the following formula:

[0149] Where: η is the corrosion inhibition rate, %; Δm0 is the weight loss of the coupon in the blank test, in grams (g); Δm1 is the weight loss of the coupon after adding the corrosion inhibitor, in grams (g).

[0150] The corrosion inhibition rates of the samples using the scale and corrosion inhibitors provided in Examples 1 to 8 were statistically analyzed, and the results are shown in Table 1:

[0151] Table 1

[0152] It can be seen from Table 1 that the scale and corrosion inhibitor provided by the present invention has excellent corrosion inhibition performance at 80° C., and the corrosion inhibition efficiency can reach more than 80%. In a better embodiment, the corrosion inhibition efficiency can reach 98%.

[0153] Test Example 2:

[0154] The scale and corrosion inhibitors provided in Examples 1 to 8 were tested for their corrosion inhibition performance under high temperature and high pressure.

[0155] The specific test process is as follows: the scale and corrosion inhibitors provided in Examples 1 to 8 were subjected to corrosion tests in high-temperature and high-pressure environments containing H2S and CO2. The corrosion test process was carried out in accordance with the American Society for Testing and Materials standard ASTM G111 "Standard Guide for Corrosion Tests in High Temperature or High Pressure Environment, or Both". Among them, the material of the test piece is the BG110SS seamless steel pipe material used for wellbore oil pipes, the corrosion test medium is an aqueous solution containing 50,000 ppm NaCl, 1,000 ppm H2S and 300 ppm CO2, the concentration of the scale and corrosion inhibitor is 1,500 ppm (based on the total mass of the corrosion test medium as 100%), the H2S partial pressure is 0.5 MPa, the CO2 partial pressure is 3.0 MPa, the total pressure is 10 MPa, the temperature environment is 180°C, and the oxygen environment is anaerobic. After 72 hours of corrosion under the above conditions, the corrosion inhibition rate η is determined according to the method of Test Example 1.

[0156] The corrosion inhibition rates of the samples using the scale and corrosion inhibitors provided in Examples 1 to 8 under high temperature and high pressure were statistically analyzed, and the results are shown in Table 2:

[0157] Table 2

[0158] It can be seen from Table 2 that the scale and corrosion inhibitor provided by the present invention has excellent corrosion inhibition performance at a high temperature of 180° C., and the corrosion inhibition efficiency can reach more than 45%. In a better embodiment, the corrosion inhibition efficiency can reach more than 93%.

[0159] Test Example 3:

[0160] The scale inhibition performance of the scale and corrosion inhibitors provided in Examples 1 to 8 was tested.

[0161] The specific testing process involved evaluating the scale inhibition performance of the scale and corrosion inhibitors provided in Examples 1-8 using a static scale inhibition test. The static scale inhibition test procedures were based on the China Petroleum Enterprise Standard Q / SY 126-2014, "Technical Specifications for Scale and Corrosion Inhibitors for Oilfield Water Treatment," Section A.3.3, "CaCO3 Scale Inhibition Rate." The scale and corrosion inhibitors were used at a concentration of 100 ppm, and the calcium ion content was determined by EDTA titration.

[0162] The scale inhibition performance is expressed as the scale inhibition rate X (%), which is determined according to the following formula:

[0163] Where: V1 is the volume of EDTA standard solution consumed after adding scale inhibitor, in milliliters (mL); V0 is the volume of EDTA standard solution consumed in the titration of blank 1 solution, in milliliters (mL); V is the volume of EDTA standard solution consumed in the titration of blank 2 solution, in milliliters (mL);

[0164] The scale inhibition rates of the samples using the scale and corrosion inhibitors provided in Examples 1 to 8 were statistically analyzed, and the results are shown in Table 3:

[0165] Table 3

[0166] It can be seen from Table 3 that the scale and corrosion inhibitor provided by the present invention has excellent scale inhibition performance, and the scale inhibition efficiency can reach more than 90%. In a better embodiment, the scale inhibition efficiency can reach more than 98%.

[0167] Test Example 4:

[0168] The scale inhibition performance of the scale and corrosion inhibitors provided in Examples 1 to 8 was tested at a high temperature of 180°C.

[0169] The specific test process is: a static scale inhibition experiment is used to evaluate the scale inhibition performance of the scale and corrosion inhibitors provided in Examples 1 to 8 at a high temperature of 180°C. The static scale inhibition test process refers to the static scale inhibition test process and is carried out in accordance with Section A.3.3 "Scale Inhibition Rate of CaCO3 Scale" of China Petroleum Enterprise Standard Q / SY 126-2014 "Technical Specifications for Corrosion and Scale Inhibitors for Oilfield Water Treatment"; wherein, the following adjustments are made when executing step a) of Section 3.3.1: Take 200 mL of distilled water and place it in a 250 mL volumetric flask. Accurately add 6.00 mL of CaCl solution and 7.5 mL of scale and corrosion inhibitor solution. Let it stand for 10 minutes. Then, add 6.00 mL of Na2CO3 solution dropwise while shaking. Dilute to the scale with distilled water and shake well. The above solution is placed in a 500 mL hydrothermal reactor, covered with a sealing lid, and placed in a 50°C ± 1°C water bath. Maintain the temperature for half an hour. After temperature equilibrium, open the bottle cap to release air, then close the bottle cap again and let it stand in an oven at 180°C ± 5°C for 16 hours.

[0170] The scale and corrosion inhibitor was used at a concentration of 1500 ppm, and the calcium ion content was determined by EDTA titration.

[0171] The scale inhibition performance is expressed as the scale inhibition rate X (%), which is determined according to the following formula:

[0172] Where: V1 is the volume of EDTA standard solution consumed after adding scale inhibitor, in milliliters (mL); V0 is the volume of EDTA standard solution consumed by titrating blank 1 solution, in milliliters (mL); V is the volume of EDTA standard solution consumed by titrating blank 2 solution, in milliliters (mL).

[0173] The scale inhibition rates of the samples using the scale and corrosion inhibitors provided in Examples 1 to 8 were statistically analyzed, and the results are shown in Table 4:

[0174] Table 4

[0175] It can be seen from Table 4 that the scale and corrosion inhibitor provided by the present invention has excellent scale inhibition performance at high temperatures. At 180° C., the scale inhibition efficiency can reach 81.3% in a better embodiment.

[0176] Test Example 5:

[0177] The intermediate product and the final product in Example 5 were characterized by Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy, respectively. The results are shown in Figures 1, 2, 3 and 4.

[0178] Figure 1 is a Fourier transform infrared spectrum characterization diagram of the intermediate product in Example 5. In Figure 1, 1300.15 cm -1 、1349.97cm -1、1384.29cm -1 The small and sharp absorption peak at 1492.48 cm is attributed to the stretching vibration of the CH bond in the alkyl group. -1 The small and sharp peak at 1598.2 cm is attributed to the deformation vibration of the CN bond. -1 The strong absorption peak near 762.49 cm is attributed to the stretching vibration of NH. -1 The absorption peak at 700.61 cm is attributed to the stretching vibration peak of CS. -1 The stretching vibration peak of carbonyl C=O is located at 1690 cm-1, which is attributed to the out-of-plane bending vibration of phenyl CH bond. -1 -1750cm -1 , merged with the characteristic peak of NH into a broad and strong peak at 2819.31 cm -1 The broadband absorption band is attributed to the distortion vibration of C=N, 3411.81cm -1 The broadband strong absorption band at is attributed to the stretching vibration of OH. Figure 3 is a nuclear magnetic spectrum characterization diagram of the intermediate product in Example 5. In Figure 3, 1H NMR (DMSO, 400MHz), the chemical shift at 1.83ppm is the proton peak of the secondary amine -NH, the chemical shifts at 2.65ppm and 2.67ppm are the proton peaks of the methylene in -NH-CH2-CH2-NH-, the proton peak at 7.23ppm-7.31ppm is the proton peak on the phenyl group, the chemical shift at 8.14ppm-8.21ppm is the proton peak of -CH=CH- on the thiazole ring, the chemical shift at 6.5ppm is the proton peak of -CH=CH- connected to the phenyl group, and the chemical shift at 3.41ppm-3.45ppm is the proton peak of the methine group.

[0179] Figure 2 is a Fourier transform infrared spectrum characterization diagram of the final product in Example 5. In Figure 2, 1294.32 cm -1 、1351.98cm -1 、1384.40cm -1 The small and sharp absorption peak at 1493.48 cm is attributed to the stretching vibration of the CH bond in the alkyl group. -1 The small and sharp peak at 1599.38 cm is attributed to the deformation vibration of the CN bond. -1 The strong absorption peak near 765.14 cm is attributed to the stretching vibration of NH -1 The absorption peak at 702.17 cm is attributed to the stretching vibration peak of CS. -1 The stretching vibration peak of carbonyl C=O is located at 1690-1750 cm-1, which is attributed to the out-of-plane bending vibration of phenyl CH bond. -1 , merged with the characteristic peak of NH into a broad and strong peak at 2800 cm -1The broadband absorption band is attributed to the distortion vibration of C=N, which is weakened by the quaternization reaction. -1 The broad and strong absorption band at 1080.84 cm is attributed to the stretching vibration of OH. -1 The characteristic absorption peak at 937.24 cm is attributed to the introduction of P=O stretching vibration. -1 The induced POC bending vibration is 873.55 cm -1 The C-Cl absorption peak at is almost invisible, which is attributed to the conversion of the C-Cl bond into a CN bond by the quaternization reaction. FIG4 is a nuclear magnetic spectrum characterization diagram of the final product in Example 5. In Figure 4, 1H NMR (DMSO, 400 MHz), the chemical shift at 1.23 ppm is the proton peak of -N-CH2-C- introduced into HCP, the chemical shift at 1.84 ppm is the proton peak of the secondary amine -NH, the chemical shift at 1.91 ppm is the proton peak of -OH introduced into HCP, the chemical shift at 2.64 ppm-2.88 ppm is the proton peak of the methylene in -NH-CH2-CH2-NH-, the chemical shift at 3.01 ppm-3.38 ppm is the proton peak of the methine, the chemical shift at 6.52 ppm is the proton peak of -CH=CH-, the chemical shift at 7.32 ppm-7.42 ppm is the proton peak on the phenyl group, and the chemical shift at 7.66 ppm-7.68 ppm is the proton peak of -CH=CH- on the thiazole ring.

[0180] The final products of Examples 5-8 were subjected to thermogravimetric analysis, and the results are shown in Figure 5. Example 7 exhibited significant weight loss at 190°C, attributed to the thermal decomposition reaction of the compound, and significant weight loss again at 270°C, attributed to secondary thermal decomposition of the sample. Example 5 exhibited significant weight loss at 268°C, attributed to the thermal decomposition reaction of the compound. Example 6 exhibited significant weight loss at 249°C, attributed to the thermal decomposition reaction of the compound. Example 8 exhibited significant weight loss at 266°C, also attributed to the thermal decomposition reaction of the compound. Thermal analysis demonstrated that the final products of Examples 5-8 possessed excellent thermal stability.

[0181] Thus, specific embodiments of the subject matter have been described. Other embodiments are within the scope of the following claims. In some cases, the actions recited in the claims can be performed in a different order and still achieve the desired results. Furthermore, the processes depicted in the accompanying drawings do not necessarily require the particular order shown, or sequential order, to achieve the desired results.

Claims

1. A compound for scale and corrosion inhibitor, which has the structure shown in Formula I:

2. The compound for scale and corrosion inhibitor according to claim 1, wherein, R1 is selected from one of substituted or unsubstituted alkyl, aminoalkyl; R2 is selected from one of H and substituted or unsubstituted aryl; R3 is selected from substituted or unsubstituted five - or six - membered heterocyclic rings containing heteroatoms.

3. The compound for scale and corrosion inhibitor according to claim 2, wherein, R1 is selected from one of them.

4. The compound for scale and corrosion inhibitor according to claim 2, wherein, R2 is selected from and one of them.

5. The compound for scale and corrosion inhibitor according to claim 2, wherein, R3 is selected from one of the following.

6. A preparation method of a scale and corrosion inhibitor, which comprises the following steps: Mix an aldehyde, a polyamine, a ketone and a first polar solvent to obtain a first mixture; wherein, the molar ratio of the aldehyde, the polyamine, and the ketone is 1.0 - 1.2:0.5:1.0 - 1.2; the volume of the first polar solvent is 3 - 5 times the total volume of the aldehyde, the polyamine and the ketone; Adjust the pH of the first mixture to 2 - 6, then carry out a first - step heating reaction under the protection of an inert gas, and carry out a first - step purification treatment on the product obtained from the first - step heating reaction to remove the remaining reactants to obtain an intermediate product; Mix a second polar solvent, sodium 2 - hydroxy - 3 - chloropropyl phosphate and the intermediate product to obtain a second mixture; wherein, the mass ratio of the second polar solvent, sodium 2 - hydroxy - 3 - chloropropyl phosphate and the intermediate product is 100:0.5 - 1:5 - 10; Carry out a second - step heating reaction on the second mixture, and remove the solid precipitate in the product obtained from the second - step heating reaction, and then prepare the scale and corrosion inhibitor.

7. According to the preparation method of claim 6, wherein, The polyamine includes at least one of ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine; The aldehyde includes one of cinnamaldehyde, formaldehyde and benzaldehyde; The ketone includes one of 2 - acetylthiazole, 1 - acetylimidazole and 3 - acetylpyridine.

8. According to the preparation method of claim 6, wherein, The first solvent includes at least one of absolute ethanol, deionized water, dimethyl sulfoxide, N,N - dimethylformamide; The second polar solvent includes at least one of absolute ethanol, deionized water, dimethyl sulfoxide, N,N - dimethylformamide.

9. The preparation method according to claim 6, wherein The reagent used for adjusting the pH of the first mixture is hydrochloric acid; Calculated based on the mass of hydrochloric acid being 100%, the mass concentration of HCl in hydrochloric acid is 5 - 20%.

10. According to the preparation method of claim 6, wherein, The temperature of the first - step heating reaction is 70 - 100 °C; The time of the first - step heating reaction is 4 - 10 h; The temperature of the second - step heating reaction is 75 - 95 °C; The time of the second - step heating reaction is 5 - 24 h.

11. The preparation method according to claim 6, wherein Carrying out the first - step purification treatment on the product obtained from the first - step heating reaction includes: rotary - evaporating and concentrating the product obtained from the first - step heating reaction until the solvent completely volatilizes, and then using a third polar solvent and an antisolvent to remove the remaining reactants; wherein, the volume ratio of the solvent and the antisolvent is 1:2 - 5; Wherein, the third polar solvent includes at least one of absolute ethanol, deionized water, dimethyl sulfoxide, N,N - dimethylformamide; Wherein, the antisolvent includes at least one of ether, ethyl acetate, methyl acetate, acetone.

12. The preparation method according to claim 11, wherein, The ratio of the mass of the product after rotary - evaporating and concentrating until the solvent completely volatilizes to the mass of the third polar solvent is 1:5 - 15.

13. The preparation method according to claim 11, wherein, Removing the remaining reactants by using a third polar solvent and an antisolvent includes: adding the third polar solvent, then removing the solid precipitate, and then adding the antisolvent. After stirring and mixing, ice bath extraction is carried out to remove the remaining reactants.

14. The preparation method according to claim 6, wherein, This method further includes: Mixing the product obtained by removing the solid precipitate from the product obtained in the second-step heating reaction with a fourth polar solvent and optionally an auxiliary agent to prepare a scale and corrosion inhibitor; wherein the fourth polar solvent includes at least one of absolute ethanol, deionized water, dimethyl sulfoxide, and N,N-dimethylformamide; wherein the auxiliary agent includes at least one of potassium iodide, 2-methyl-3-butyn-2-ol, propargyl alcohol, and β-cyclodextrin; wherein, based on the mass of the product obtained by removing the solid precipitate from the product obtained in the second-step heating reaction being 100%, the mass of the polar solvent is more than 30%; wherein, based on the mass of the product obtained by removing the solid precipitate from the product obtained in the second-step heating reaction being 100%, the mass of the auxiliary agent is 5-15%.

15. A scale and corrosion inhibitor, which comprises the compound for scale and corrosion inhibitor according to any one of claims 1-5.

16. The scale and corrosion inhibitor according to claim 15, wherein, This scale and corrosion inhibitor further includes a polar solvent; wherein the polar solvent includes at least one of absolute ethanol, deionized water, dimethyl sulfoxide, and N,N-dimethylformamide.

17. The scale and corrosion inhibitor according to claim 15, wherein, This scale and corrosion inhibitor further includes an auxiliary agent; wherein the auxiliary agent includes at least one of potassium iodide, 2-methyl-3-butyn-2-ol, propargyl alcohol, and β-cyclodextrin.

18. The scale and corrosion inhibitor according to claim 15, wherein, This scale and corrosion inhibitor is prepared by using the preparation method of the scale and corrosion inhibitor according to any one of claims 6-14.

19. Application of the scale and corrosion inhibitor according to any one of claims 15-18 in the development of sulfur-containing gas fields.

20. The application according to claim 19, wherein, The application environment temperature of the scale and corrosion inhibitor is 0-180°C.

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