Acidizing corrosion inhibitor, acidizing working fluid, preparation method and application of acidizing working fluid

Abstract

The present application discloses a kind of acidizing corrosion inhibitor, acidizing working fluid, the preparation method and application of acidizing working fluid, belong to the field of oil drilling technology.The acidizing corrosion inhibitor of the present application contains formula i compound;Or, containing the composition of formula i compound and hexamethylenetetramine with a mass ratio of (0.5-2.0):(0.5-4.0);Or, containing the composition of formula i compound and 3-phenyl-2-propyn-1-alcohol with a mass ratio of (0.5-2.0):(1.0-7.0);Or, containing the composition of formula i compound, hexamethylenetetramine and 3-phenyl-2-propyn-1-alcohol with a mass ratio of (0.5-2.0):(0.5-4.0):(1.0-7.0). The acidizing corrosion inhibitor of the present application can not only effectively enhance the adsorption and complexing ability of the corrosion inhibitor with the metal surface, showing better corrosion inhibition performance, but also effectively improve the temperature resistance of the corrosion inhibitor, and can show efficient and stable corrosion inhibition performance in the temperature range of 60-160°C. It has good application prospects for acidizing corrosion inhibition operations in deep well conditions.

Description

Technical Field

[0001] The present invention belongs to the technical field of oil drilling, and in particular relates to an acidizing corrosion inhibitor, an acidizing working fluid, and a preparation method and application of the acidizing working fluid. Background Art

[0002] Oil well acidizing is an effective method for increasing oil and gas recovery and has been widely used in oilfield production. However, the acidizing process can easily cause corrosion of metal components such as downhole tubing and oilfield equipment. Therefore, the addition of corrosion inhibitors is necessary to mitigate this corrosion problem during the acidizing process.

[0003] Phenanthroline is an N-heterocyclic compound with multiple adsorption centers in its molecular structure. It can form stable complexes with many metals and effectively inhibit the corrosion of metals in acidic media. As a corrosion inhibitor, it has the advantages of good corrosion inhibition effect, good water solubility, small dosage and simple preparation. It is one of the research hotspots in the field of corrosion inhibitors.

[0004] However, since the discussion of the corrosion inhibition ability of 1,1-phenanthroline and its derivatives in related technologies mainly focuses on the low temperature range of 30-50°C, 1,1-phenanthroline and its derivatives corrosion inhibitors generally have the problems of low applicable temperature and narrow temperature resistance range, especially they cannot meet the bottom hole working conditions with temperatures above 90°C. Summary of the Invention

[0005] The present application discloses an acidizing corrosion inhibitor, an acidizing working fluid, a preparation method and an application of the acidizing working fluid, thereby effectively solving the technical problems of low applicable temperature and narrow temperature resistance range of 1,2-phenanthroline and its derivative corrosion inhibitors.

[0006] In order to achieve the above objectives, the present application provides an acidifying corrosion inhibitor applicable to temperatures of 60-160° C. in the first technical solution. The acidifying corrosion inhibitor of the present application mainly contains a compound of formula I:

[0007]

[0008] In a preferred technical solution, the acidifying corrosion inhibitor of the present application mainly contains a compound of formula I and one of hexamethylenetetramine and / or 3-phenyl-2-propyn-1-ol. The mass ratio of the compound of formula I to hexamethylenetetramine is (0.5-2.0):(0.5-4.0); and the mass ratio of the compound of formula I to 3-phenyl-2-propyn-1-ol is (0.5-2.0):(1.0-7.0).

[0009] In a more preferred technical solution, the acidifying corrosion inhibitor of the present application mainly contains the compound of formula I, hexamethylenetetramine and 3-phenyl-2-propyn-1-ol, wherein the mass ratio of the compound of formula I, hexamethylenetetramine and 3-phenyl-2-propyn-1-ol is (0.5-2.0):(0.5-4.0):(1.0-7.0).

[0010] In a preferred technical solution, the present application also provides a method for preparing a compound of formula I, comprising the steps of:

[0011] After 1,10-phenanthroline and 2-chloroacetophenone are reacted in an organic solvent, the reaction product is subjected to rotary evaporation and vacuum drying in sequence to obtain a compound of formula I.

[0012] In a more preferred technical solution, the molar ratio of 1,10-phenanthroline to 2-chloroacetophenone is 1.0:1.1.

[0013] The second technical solution of the present application also provides the use of the acidizing corrosion inhibitor of the present application in the preparation of an acidizing working fluid.

[0014] The third technical solution of the present application further provides an acidizing working fluid, which comprises an acidizing fluid and an acidizing corrosion inhibitor dispersed in the acidizing fluid, wherein the acidizing corrosion inhibitor is selected from the acidizing corrosion inhibitor provided in the first technical solution of the present application.

[0015] In a preferred technical solution, the mass percentage of the acidizing corrosion inhibitor of the present application in the acidizing solution is 0.2-5wt%.

[0016] In a preferred technical solution, the acidifying liquid of the present application can be selected from a hydrochloric acid solution with a mass concentration of 12-20wt%.

[0017] The present application further provides a method for preparing an acidified working fluid in a fourth technical solution, comprising the steps of:

[0018] According to the composition of the acidizing working fluid provided by the third technical solution of the present application, the acidizing corrosion inhibitor component is added to the acidizing fluid and ultrasonically dissolved to obtain the acidizing working fluid.

[0019] The fifth technical solution of the present application also provides the application of the acidizing working fluid of the present application in the acidizing corrosion inhibition treatment of oil and gas fields.

[0020] Compared with the prior art, the advantages or beneficial effects of the embodiments of the present application include at least:

[0021] The acidizing corrosion inhibitor provided herein primarily contains a compound of formula I. Due to its specific molecular structure and the active groups it contains, the compound of formula I exhibits enhanced hydrophilicity, more adsorption active sites, and greater molecular planar structure and structural rigidity. This not only effectively enhances the inhibitor's adsorption and complexing ability with metal surfaces, exhibiting improved corrosion inhibition performance, but also effectively improves the inhibitor's temperature resistance, enabling it to exhibit efficient and stable corrosion inhibition performance within a temperature range of 60-160°C. Furthermore, the acidizing corrosion inhibitor of this application offers the advantages of low concentration and simple preparation methods, making it suitable for acidizing corrosion inhibition operations in deep well conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] To more clearly illustrate the technical solutions of the embodiments of this application, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some of the embodiments described in this application. For those skilled in the art, other drawings can be derived from these drawings without inventive effort.

[0023] Figure 1 The infrared spectrum of the compound of formula I provided in the examples of the present application;

[0024] Figure 2 The hydrogen nuclear magnetic resonance spectrum of the compound of formula I provided in the examples of the present application;

[0025] Figure 3 The carbon NMR spectrum of the compound of formula I provided in the examples of the present application;

[0026] Figure 4 The electrochemical impedance spectroscopy provided in the examples of this application;

[0027] Figure 5 The electrochemical polarization curve provided in the examples of this application;

[0028] Figure 6 This is the surface morphology of J55 steel provided in the examples of the present application before and after treatment with acidizing working fluid. DETAILED DESCRIPTION

[0029] The following will be combined with the accompanying drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0030] In the following description of this embodiment, the term "and / or" is used to describe the association relationship between associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, B exists alone, and A and B exist at the same time. A and B can be singular or plural.

[0031] In the following description of this embodiment, the term "at least one" refers to one or more, and "plurality" refers to two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, "at least one of A, B or C", or "at least one of A, B and C" can mean any one of A, B, C, or A+B, or A+C, or B+C, or A+B+C, where A, B, and C can be single or multiple.

[0032] In the following description of this embodiment, the order of serial numbers does not mean the order of execution. Some or all steps can be executed in parallel or sequentially. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of this application.

[0033] In the following description of the present embodiment, numerical ranges should be understood to also specifically disclose each intervening value between the upper and lower limits of the range. Each smaller range between any stated value or intervening value in a stated range and any other stated value or intervening value in the stated range is also included in the present invention. The upper and lower limits of these smaller ranges may independently be included or excluded in the range.

[0034] Unless otherwise indicated, the technical / scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which this application belongs. Although this application describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of this application. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials related to the documents. In the event of any conflict with any incorporated document, the content of this specification shall prevail.

[0035] In one technical solution, the acidifying corrosion inhibitor provided in the embodiment of the present application mainly contains a compound of formula I:

[0036]

[0037] The acidizing corrosion inhibitor provided in this application primarily contains a compound of formula I. Due to its specific molecular structure and the active groups it contains, the compound of formula I exhibits improved hydrophilicity, more adsorption active sites, and higher molecular planar structure and structural rigidity. This not only effectively enhances the inhibitor's adsorption and complexing ability with metal surfaces, exhibiting improved corrosion inhibition performance, but also effectively improves the inhibitor's temperature resistance, enabling it to exhibit stable and efficient corrosion inhibition performance within a temperature range of 60-160°C. Furthermore, the acidizing corrosion inhibitor in this application has the advantages of low concentration and dosage, antibacterial properties, and a simple preparation method, making it suitable for acidizing corrosion inhibition operations in deep well conditions.

[0038] In some preferred technical solutions, the acidifying corrosion inhibitor provided in the embodiments of the present application mainly contains a compound of formula I and one of hexamethylenetetramine and / or 3-phenyl-2-propyn-1-ol. The mass ratio of the compound of formula I to hexamethylenetetramine is (0.5-2.0):(0.5-4.0); and the mass ratio of the compound of formula I to 3-phenyl-2-propyn-1-ol is (0.5-2.0):(1.0-7.0).

[0039] It should be noted that the embodiments of the present application specifically compound the compound of formula i and hexamethylenetetramine, so that the compound i and hexamethylenetetramine form a stable aggregate structure with molecular structural rigidity and increased planar area based on the supramolecular effect, effectively enhancing the corrosion inhibition performance and temperature resistance.

[0040] It is understood in the art that the mass ratio of the compound of formula I to hexamethylenetetramine contained in the acidifying corrosion inhibitor of the present application can be illustratively 0.8:3.2, 1.0:2.0, 1.0:0.8, 1.5:1.0, or any other mass ratio within the aforementioned range. In particular, by controlling this mass ratio, the present application controls the aggregate structure formed by the compound of formula I and hexamethylenetetramine based on supramolecular forces to be more uniformly distributed and stable, effectively improving the protective coverage effect on the metal surface and enhancing the corrosion inhibition performance.

[0041] It should be understood in the art that the mass ratio of the compound of formula I to 3-phenyl-2-propyn-1-ol contained in the acidifying corrosion inhibitor of the present application can be illustratively 1.0:1.0, 1.0:4.0, 1.0:6.0, 1.0:7.0, or any other mass ratio within the aforementioned range. In particular, by controlling this mass ratio, the present application embodiment makes the aggregate structure formed by the compound of formula I and 3-phenyl-2-propyn-1-ol based on supramolecular forces more uniform and stable, effectively improving the coverage and protection effect on the metal surface, thereby enhancing the corrosion inhibition performance.

[0042] In some preferred technical solutions, the acidifying corrosion inhibitor provided in the embodiments of the present application mainly contains a compound of formula I, hexamethylenetetramine, and 3-phenyl-2-propyn-1-ol. The mass ratio of the compound of formula I, hexamethylenetetramine, and 3-phenyl-2-propyn-1-ol is (0.5-2.0):(0.5-4.0):(1.0-7.0).

[0043] It should be noted that the embodiment of the present application specifically compounds the compound of formula i, hexamethylenetetramine and 3-phenyl-2-propyn-1-ol, so that the compound i, hexamethylenetetramine and 3-phenyl-2-propyn-1-ol form an aggregate structure with further increased molecular structural rigidity and planar area based on the supramolecular effect, effectively improving the corrosion inhibition performance and temperature adaptability, further reducing the corrosion rate of metal parts by the acidizing solution containing the acidizing corrosion inhibitor, and effectively broadening the applicable well temperature range. Wherein, the aggregate structure here can be shown in formula ii:

[0044]

[0045] It should be understood in the art that the mass ratio of the compound of formula I, hexamethylenetetramine, and 3-phenyl-2-propyn-1-ol contained in the acidifying corrosion inhibitor of the embodiment of the present application can be illustratively 0.8:3.2:4.0, 0.8:3.2:6.0, 1.0:2.0:4.0, 1.0:0.8:7.0, 1.5:1.0:6.0, or any one within the mass ratio range. Among them, the embodiment of the present application controls the mass ratio to make the aggregate structure formed by the compound of formula I, hexamethylenetetramine, and 3-phenyl-2-propyn-1-ol based on supramolecular forces more uniform and stable, effectively improving the coverage and protection effect on the metal surface, so that the corrosion inhibition performance is enhanced.

[0046] In order to facilitate the implementation of the acidifying corrosion inhibitor of the embodiment of the present application in the art, the embodiment of the present application also provides a method for preparing the compound of formula I, preferably comprising the steps of:

[0047] After reacting 1,10-phenanthroline and 2-chloroacetophenone in an organic solvent, the reaction product is subjected to rotary evaporation and vacuum drying in sequence to obtain a compound of formula I. To ensure efficient reaction between 1,10-phenanthroline and 2-chloroacetophenone and facilitate subsequent separation and purification, the molar ratio of 1,10-phenanthroline to 2-chloroacetophenone is preferably 1.0:1.1.

[0048] It should be noted that the embodiments of the present application do not particularly limit the material composition and specific source of the organic solvent, and various good solvents for 1,10-phenanthroline and 2-chloroacetophenone known in the art can be used, such as acetone, dimethyl sulfoxide, dimethylformamide, etc.; at the same time, the embodiments of the present application do not particularly limit the various parameters of rotary evaporation and vacuum drying, and reasonable selection can be made according to actual needs in the field.

[0049] The present application provides an exemplary preparation process of the compound of formula I, which specifically includes the steps of:

[0050] Step 1: Place 1,10-phenanthroline and 2-chloroacetophenone in a molar ratio of 1.0:1.1 (total mass 33.4 g) into a dry round-bottom flask, add 250 mL of acetone as a solvent, mix under stirring, and heat to reflux for 24 hours;

[0051] Step 2: After the reflux is completed, the product is taken out and cooled and evaporated, and then dried under reduced pressure at 60°C for 24 h to obtain a crude product (32.0 g);

[0052] Step 3: The crude product was recrystallized twice from acetone solvent and dried under reduced pressure in a vacuum oven at 60°C for 24 h to obtain a purple-red solid product (31.0 g), which is the compound of formula I.

[0053] In order to verify the successful synthesis of the compound of formula I, the prepared compound of formula I was subjected to infrared spectroscopy, nuclear magnetic resonance spectroscopy ( 1 H NMR) and 13C NMR characterization, the characterization results are as follows Figures 1 to 3 As shown. Among them, Figure 1 is the infrared spectrum of the compound of formula i; Figure 2 is the hydrogen nuclear magnetic resonance spectrum of the compound of formula I; Figure 3 is the carbon NMR spectrum of the compound of formula I.

[0054] according to Figure 1 It can be seen that 2995cm -1 -CH stretching vibration absorption peak in -CH-; 1681cm -1 The -C=O double bond stretching vibration peak appeared; 1629cm -1 and 1592cm -1 The absorption peaks that appear are the stretching vibration peaks of the C=C double bond in the aromatic ring and the stretching vibration peaks of the -C=N double bond on the phenanthroline ring; 1453 cm -1 -CN appears + -C- quaternary nitrogen characteristic peak; 1341cm -1 N + -Bending vibration absorption of CH2 bond; 900-675cm -1 This is the absorption peak caused by the out-of-plane bending vibration of the aromatic ring.

[0055] 1 H NMR(600MHz,Methanol-d4)δ9.45(m,1H),9.26(dd,J=4.9,1.5Hz,2H),8.98(dd,J=8.2,1.6Hz,2H),8.38(s,1H),8 .28(s,2H),8.25–8.19(m,1H),8.17(dd,J=8.3,4.9Hz,2H),7.85–7.75(m,1H),7.70(m,2H),7.51(t,J=7.9Hz,1H).

[0056] 13C NMR(151MHz,MeOD)δ190.35,148.74,148.08,147.99,140.73,139.73,137.71,134.01,1 32.67,130.85,129.63,128.99,128.06,127.07,126.67,125.30,124.59,124.14,69.80.

[0057] according to Figures 1 to 3 From the characterization results, it can be seen that the compound of formula I, specifically 1,10-phenanthroline quaternary ammonium salt, was successfully synthesized through the above-mentioned preparation process in the embodiment of the present application.

[0058] In the second technical solution, the present invention also provides an embodiment of the present invention for use in preparing an acidizing working fluid. The acidizing working fluid based on the present invention has excellent corrosion inhibition and temperature resistance, making it suitable for bottomhole acidizing treatment at temperatures between 60°C and 160°C.

[0059] In the third technical solution, the embodiment of the present application further provides an acidizing working fluid. The acidizing working fluid of the embodiment of the present application comprises an acidizing fluid and the above-mentioned acidizing corrosion inhibitor dispersed in the acidizing fluid.

[0060] It should be understood in this field that acidizing fluid refers to the acidizing fluid commonly used in oil and gas well acidizing operations, which is mainly used to dissolve blockages and reservoir rock minerals generated during oil and gas well operations, restore and improve the permeability of the reservoir, and achieve the effect of increasing oil and gas field production and injection. Among them, the acidizing fluid can be a common single acid system such as HCl, HF, or a known HCl-HF, organic acid-HF composite system and acidizing acid system. Of course, the acidizing fluid of the embodiment of the present application also contains various additives commonly found in acidizing working fluids. The embodiment of the present application does not impose any special restrictions on the system type, concentration and additives of the acidizing fluid, so long as it can meet the requirements of downhole acidizing operations in oil and gas fields.

[0061] In some preferred technical solutions, the mass percentage of the acidizing corrosion inhibitor of the embodiments of the present application in the acidizing fluid is 0.2-5wt%, exemplified by 0.2wt%, 0.5wt%, 1.0wt%, 2.0wt%, 3.0wt%, 4.0wt%, 5.0wt%, etc. The mass percentage here can be reasonably selected according to the downhole working conditions of the oil and gas field. For example, when facing a bottom hole temperature of 120-160°C, the mass concentration of the acidizing corrosion inhibitor of the present application in a 20% HCl acidizing fluid can be 4.0wt%; when facing a bottom hole temperature of 60-90°C, the mass concentration of the acidizing corrosion inhibitor of the present application in a 20wt% HCl acidizing fluid can be 0.5wt%.

[0062] In some preferred technical solutions, the acidizing fluid in the embodiments of the present application can be selected from a hydrochloric acid solution with a mass concentration of 12-20 wt%, illustratively selected from common 12 wt% HCl and 20 wt% HCl. The person skilled in the art can reasonably select according to the needs of downhole acidizing construction in oil and gas fields.

[0063] It should be noted that, in the embodiment of the present application, hydrochloric acid and distilled water with a concentration of 20 wt % are preferably prepared according to formulas (1) and (2), and the distilled water meets the requirements of grade 3 water in GB / T 6682-2008.

[0064] When preparing the solution, slowly add hydrochloric acid to distilled water while stirring until evenly mixed. Determine the actual concentration by titration with an error of no more than ±0.2%.

[0065] The amount of hydrochloric acid is calculated according to formula (1):

[0066]

[0067] In formula (1):

[0068] V0----amount of hydrochloric acid used, in milliliters (mL);

[0069] ρ0----density of hydrochloric acid, in grams per cubic centimeter (g / cm 3 );

[0070] W0----mass fraction of hydrochloric acid, expressed as a percentage;

[0071] V----the volume of hydrochloric acid prepared, in milliliters (mL);

[0072] ρ----density of the prepared hydrochloric acid, in grams per cubic centimeter (g / cm 3 );

[0073] W----mass fraction of the prepared hydrochloric acid, expressed as a percentage (the density of 20% hydrochloric acid is 1.1004 g / cm 3 ).

[0074] The amount of distilled water is calculated according to formula (2):

[0075]

[0076] Where: V1----the amount of distilled water in the prepared hydrochloric acid, in milliliters (mL);

[0077] ρ1 - density of water at room temperature, in grams per cubic centimeter (g / cm 3 ).

[0078] In the fourth technical solution, in order to facilitate the implementation of the acidification working fluid of the embodiment of the present application in the art, the embodiment of the present application further provides a method for preparing the acidification working fluid, preferably comprising the steps of:

[0079] According to the composition of the acidizing working solution provided in the third embodiment of the present application, the acidizing corrosion inhibitor component is added to the acidizing solution and dissolved by ultrasonication to obtain the acidizing working solution. The ultrasonication is used to fully disperse the acidizing corrosion inhibitor component in the acidizing solution and form a stable dispersion system. Therefore, other auxiliary methods, such as mechanical stirring, can be reasonably substituted.

[0080] In the fifth technical solution, the present invention also provides an embodiment of the present invention's application of the acidizing working fluid in oil and gas field acidizing and corrosion inhibition treatment. The acidizing working fluid based on the present invention's embodiment is suitable for bottomhole acidizing treatment at temperatures between 60°C and 160°C. Therefore, when used in oil and gas field acidizing and corrosion inhibition treatment, it can provide efficient and stable acidizing and corrosion inhibition effects.

[0081] The technical solution of the present application will be further described below in conjunction with specific embodiments.

[0082] Example 1

[0083] This embodiment provides the preparation of an acidified working solution A having a mass concentration of 4.0 wt%, comprising the steps of:

[0084] 4 g of 1,10-phenanthroline quaternary ammonium salt and 100 g of 20 wt % hydrochloric acid solution were placed in a 250 mL wide-mouth bottle and ultrasonically dissolved at 60° C. for 30 min to obtain an acidified working solution A with a concentration of 4.0 wt %.

[0085] Example 2

[0086] This embodiment provides the preparation of an acidified working solution AB with a mass concentration of 4.0 wt%, comprising the steps of:

[0087] 1,10-phenanthroline quaternary ammonium salt and hexamethylenetetramine are mixed in a mass ratio of 0.8:3.2 to obtain a binary composite acidifying corrosion inhibitor;

[0088] 4 g of binary compound acidifying corrosion inhibitor and 100 g of 20 wt % hydrochloric acid solution were placed in a 250 mL wide-mouth bottle and ultrasonically dissolved at 60° C. for 30 min to obtain an acidifying working solution AB with a mass concentration of 4.0 wt %.

[0089] Example 3

[0090] This embodiment provides the preparation of an acidified working solution AC having a mass concentration of 4.0 wt%, comprising the steps of:

[0091] 1,10-phenanthroline quaternary ammonium salt and 3-phenyl-2-propyn-1-ol are mixed in a mass ratio of 1:1 to obtain a binary composite acidifying corrosion inhibitor;

[0092] 4 g of binary compound acidifying corrosion inhibitor and 100 g of 20 wt % hydrochloric acid solution were placed in a 250 mL wide-mouth bottle and ultrasonically dissolved at 60° C. for 30 min to obtain an acidifying working solution AC with a mass concentration of 4.0 wt %.

[0093] Example 4

[0094] This embodiment provides the preparation of an acidified working solution ABC-i having a mass concentration of 4.0 wt%, comprising the steps of:

[0095] 1,10-phenanthroline quaternary ammonium salt, hexamethylenetetramine and 3-phenyl-2-propyn-1-ol were mixed in a mass ratio of 0.8:3.2:4.0 to obtain a ternary composite acidifying corrosion inhibitor i;

[0096] 4 g of ternary composite acidifying corrosion inhibitor i and 100 g of 20 wt % hydrochloric acid solution were placed in a 250 mL wide-mouth bottle and ultrasonically dissolved at 60° C. for 30 min to obtain an acidifying working solution ABC-i with a mass concentration of 4.0 wt %.

[0097] Example 5

[0098] This embodiment provides the preparation of an acidified working solution ABC-ii having a mass concentration of 4.0 wt%, comprising the steps of:

[0099] 1,10-phenanthroline quaternary ammonium salt, hexamethylenetetramine and 3-phenyl-2-propyn-1-ol were mixed in a mass ratio of 0.8:3.2:6.0 to obtain a ternary composite acidifying corrosion inhibitor ii;

[0100] 4 g of the ternary composite acidifying corrosion inhibitor ii and 100 g of a 20 wt % hydrochloric acid solution were placed in a 250 mL wide-mouth bottle and ultrasonically dissolved at 60° C. for 30 min to obtain an acidifying working solution ABC-ii with a mass concentration of 4.0 wt %.

[0101] Example 6

[0102] This embodiment provides the preparation of an acidified working solution ABC-iii having a mass concentration of 4.0 wt%, comprising the steps of:

[0103] 1,10-phenanthroline quaternary ammonium salt, hexamethylenetetramine and 3-phenyl-2-propyn-1-ol are mixed in a mass ratio of 1.0:2.0:4.0 to obtain a ternary composite acidifying corrosion inhibitor iii;

[0104] 4 g of ternary composite acidifying corrosion inhibitor iii and 100 g of 20 wt% hydrochloric acid solution were placed in a 250 mL wide-mouth bottle and ultrasonically dissolved at 60° C. for 30 min to obtain an acidifying working solution ABC-iii with a mass concentration of 4.0 wt%.

[0105] Example 7

[0106] This embodiment provides the preparation of an acidified working solution ABC-iv having a mass concentration of 4.0 wt%, comprising the steps of:

[0107] 1,10-phenanthroline quaternary ammonium salt, hexamethylenetetramine and 3-phenyl-2-propyn-1-ol are mixed in a mass ratio of 1.0:0.8:7.0 to obtain a ternary composite acidifying corrosion inhibitor IV;

[0108] 4 g of ternary composite acidifying corrosion inhibitor iv and 100 g of 20 wt% hydrochloric acid solution were placed in a 250 mL wide-mouth bottle and ultrasonically dissolved at 60° C. for 30 min to obtain an acidifying working solution ABC-iv with a mass concentration of 4.0 wt%.

[0109] Example 8

[0110] This embodiment provides the preparation of an acidified working solution ABC-v with a mass concentration of 4.0 wt%, comprising the steps of:

[0111] 1,10-phenanthroline quaternary ammonium salt, hexamethylenetetramine and 3-phenyl-2-propyn-1-ol were mixed in a mass ratio of 1.5:1.0:6.0 to obtain a ternary composite acidifying corrosion inhibitor v;

[0112] 4 g of the ternary composite acidifying corrosion inhibitor v and 100 g of a 20 wt % hydrochloric acid solution were placed in a 250 mL wide-mouth bottle and ultrasonically dissolved at 60° C. for 30 min to obtain an acidifying working solution ABC-v with a mass concentration of 4.0 wt %.

[0113] In order to illustrate the corrosion inhibition performance of the acidizing working fluid provided in the examples of the present application, the following will be analyzed and explained in combination with comparative examples 1-3.

[0114] Comparative Example 1

[0115] This comparative example provides the preparation of an acidified working solution B having a mass concentration of 4.0 wt%, comprising the steps of:

[0116] 4 g of hexamethylenetetramine and 100 g of 20 wt % hydrochloric acid solution were placed in a 250 mL wide-mouth bottle and dissolved by ultrasonic at 60° C. for 30 min to obtain an acidified working solution B with a mass concentration of 4.0 wt %.

[0117] Comparative Example 2

[0118] This comparative example provides the preparation of an acidified working solution C having a mass concentration of 4.0 wt%, comprising the steps of:

[0119] 4 g of 3-phenyl-2-propyn-1-ol and 100 g of a 20 wt % hydrochloric acid solution were placed in a 250 mL wide-mouth bottle and ultrasonically dissolved at 60° C. for 30 min to obtain an acidified working solution C with a mass concentration of 4.0 wt %.

[0120] Comparative Example 3

[0121] This comparative example provides the preparation of an acidified working solution BC having a mass concentration of 4.0 wt%, comprising the following steps:

[0122] Hexamethylenetetramine and 3-phenyl-2-propyn-1-ol were mixed in a mass ratio of 1:1 to obtain a binary composite acidifying corrosion inhibitor;

[0123] 4 g of binary compound acidifying corrosion inhibitor and 100 g of 20 wt % hydrochloric acid solution were placed in a 250 mL wide-mouth bottle and ultrasonically dissolved at 60° C. for 30 min to obtain an acidifying working solution BC with a mass concentration of 4.0 wt %.

[0124] Performance Testing

[0125] According to SY / T 5405-2019 "Test Method and Evaluation Index of Corrosion Inhibitor Performance for Acidification", the corrosion inhibition performance of the acidification working solutions of Examples 1-8 and Comparative Examples 1-3 was tested by the static coupon weight loss method (test temperature was 160°C). The specific steps are as follows:

[0126] ①Steel sheet marking: Wear weighing gloves and use a vernier caliper to measure the size of the coupon, then record the coupon number and the corresponding geometric dimensions and mass.

[0127] ② Based on the calculation that the amount of acidified working solution per square centimeter of the coupon surface area is 20 mL, the acidified working solution of the above example is poured into the autoclave.

[0128] ③ Install the coupon in the autoclave's coupon holder, ensuring that the entire coupon surface is in contact with the acidified working solution and that it does not contact the vessel walls. Fill the autoclave with nitrogen to 12 MPa. Start the temperature ramp, increasing the temperature by 160°C at a rate of 3°C / min. Record the reaction start time.

[0129] ④ After reacting for 4 hours, cut off the power supply. When the temperature drops to 80℃, release the pressure, remove the coupons, observe the corrosion conditions and make detailed records.

[0130] ⑤ After observation, rinse the hanging piece immediately with water, then scrub it with a soft brush; if it cannot be cleaned, clean it with 10% triammonium citrate; finally, wash each piece with acetone and anhydrous ethanol, and place the hanging piece on a clean filter paper.

[0131] ⑥ Weigh the coupons: Dry with cold air and place in a dryer for 20 minutes before weighing to the nearest 0.0001g. Calculate the corrosion rate and inhibition rate. The corrosion rate is calculated according to formula (3), and the inhibition rate is calculated according to formula (4):

[0132]

[0133] Where: ν i ----Single-sheet corrosion rate, in grams per square meter per hour [g / (m 2 h)];

[0134] Δt----reaction time, in hours (h);

[0135] Δm t ---Corrosion loss of coupon, in grams (g);

[0136] A t ----Surface area of coupon, in square millimeters (mm 2 ).

[0137]

[0138] Where: η----corrosion inhibition rate, expressed as a percentage;

[0139] Δm0----mass loss in blank test, in grams (g);

[0140] Δm1----Mass loss of the test piece in the corrosion inhibitor addition test, in grams (g).

[0141] The test results of the embodiment are shown in Table 1.

[0142] Table 1: Test results of the embodiment

[0143]

[0144] According to Table 1, the corrosion inhibition rate of the acidizing working solution containing the ternary compound acidizing corrosion inhibitor of the present application is above 98%, and the corrosion rate is lower than 65g / (m 2 h), meeting the standards of SY / T 5405-2019, "Performance Test Methods and Evaluation Indicators for Acidizing Corrosion Inhibitors," demonstrating that the acidizing corrosion inhibitor provided herein can significantly reduce the corrosion rate of metal parts in acidizing solutions. Specifically, when the mass ratio of 1,10-phenanthroline quaternary ammonium salt, hexamethylenetetramine, and 3-phenyl-2-propyn-1-ol was 0.8:3.2:6.0, the corrosion rate was lowest and the corrosion inhibition rate was highest.

[0145] For the electrochemical impedance spectroscopy test experiments of the acidifying corrosion inhibitors in Examples 1-8 and Comparative Examples 1-3, considering the working environment of the electrochemical workstation, according to SY / T 5405-2019 "Performance Test Methods and Evaluation Indicators for Acidifying Corrosion Inhibitors", the total mass concentration of the acidifying corrosion inhibitor is 0.5wt%, the test temperature is 60°C, and the specific test method includes:

[0146] J55 steel was used as the working electrode, saturated calomel electrode as the reference electrode, platinum electrode as the auxiliary electrode, and the test condition was 60°C. The system was tested by AC impedance spectroscopy at 0.01-100kHz and AC amplitude of 5mV. The results were Figure 4 As shown: The polarization curve was then tested, and the open circuit potential was scanned in the range of -250 to +250 mV at a rate of 1.0 mV·s -1 The corrosion current density was obtained by Tafel extrapolation method, and the inhibition efficiency η T % is calculated by formula (5), and the result is Figure 5 And as shown in Table 2. Among them, Figure 4 This is the electrochemical impedance spectroscopy of the acidified corrosion inhibitor of this application; Figure 5 is the electrochemical polarization curve of the acidizing corrosion inhibitor of the present application; Table 2 is the polarization curve parameter table of the acidizing corrosion inhibitor of the present application.

[0147]

[0148] Where: i 0 is the current density when no corrosion inhibitor is added (mA·cm -2 );

[0149] i is the current density after adding corrosion inhibitor (mA·cm -2 ).

[0150] according to Figure 4It can be seen that the capacitance arc of the acidified corrosion inhibitor containing 0.5wt% of 1,10-phenanthroline quaternary ammonium salt is increased compared with the blank group (20wt% hydrochloric acid solution), indicating that the compounding of 0.5wt% of 1,10-phenanthroline quaternary ammonium salt into the acidified solution can effectively inhibit the corrosion of metal parts; the capacitance arc of the acidified corrosion inhibitor containing 0.5wt% of the binary combination of 1,10-phenanthroline quaternary ammonium salt and hexamethylenetetramine is significantly increased compared with the acidified corrosion inhibitor containing 0.5wt% of 1,10-phenanthroline quaternary ammonium salt, indicating that 1, The combination of 10-phenanthroline quaternary ammonium salt and hexamethylenetetramine can produce a good synergistic effect; the acidizing corrosion inhibitor containing a ternary combination of 1,10-phenanthroline quaternary ammonium salt, hexamethylenetetramine and 3-phenyl-2-propyn-1-ol has a further increased capacitance arc compared to the acidizing corrosion inhibitor containing a binary combination of 1,10-phenanthroline quaternary ammonium salt and hexamethylenetetramine, indicating that the ternary combination of 1,10-phenanthroline quaternary ammonium salt, hexamethylenetetramine and 3-phenyl-2-propyn-1-ol can produce a more sufficient synergistic effect.

[0151] Table 2: Electrochemical polarization curve test results of acidified corrosion inhibitor at 60°C

[0152]

[0153]

[0154] according to Figure 4-5 As can be seen from the results in Table 2, the anodic and cathodic polarization curves of the 0.5 wt% 1,10-phenanthroline quaternary ammonium salt acidizing inhibitor, the binary combination of (1,10-phenanthroline quaternary ammonium salt and hexamethylenetetramine) acidizing inhibitor, and the ternary combination of (1,10-phenanthroline quaternary ammonium salt, hexamethylenetetramine, and 3-phenyl-2-propyn-1-ol) acidizing inhibitor all shifted toward lower currents compared to the blank conditions, and the corrosion current gradually decreased, indicating that the ternary combination acidizing inhibitor had the strongest protective effect on J55 steel. The self-corrosion potential of the ternary combination acidizing inhibitor shifted positively (<85 mV) relative to the blank conditions, indicating that the synthesized inhibitor is a mixed-type inhibitor. When the mass ratio of 1,10-phenanthroline quaternary ammonium salt, hexamethylenetetramine, and 3-phenyl-2-propyn-1-ol was 0.8:3.2:6.0, the corrosion inhibition rate reached 99.63%, indicating the best corrosion inhibition effect.

[0155] This example provides a surface morphology test experiment of J55 steel before and after acidification treatment with acidification working solution ABC-ii. The test results are Figure 6 (Magnified 500 times) as shown. Among them, Figure 6 A is the SEM image of J55 steel before acidification treatment; Figure 6 B is the SEM image of J55 steel treated with 20 wt% hydrochloric acid at 60 °C for 4 h; Figure 6C is the SEM image of J55 steel acidified with acidizing solution ABC-ii at 90°C for 4 h.

[0156] according to Figure 6 As shown in A, the surface of J55 steel before acidification treatment is relatively smooth with a few scratches;

[0157] according to Figure 6 As shown in B, the metal matrix morphology is not visible on the surface of J55 steel treated with 20wt% hydrochloric acid, and the J55 steel sheet is severely corroded;

[0158] according to Figure 6 C shows that the surface of the J55 steel sheet acidified with the acidifying working solution ABC-ii is relatively smooth and flat, and no obvious corrosion phenomena such as pitting and pitting are observed, indicating that the acidifying working solution of Example 5 can reduce the corrosion of the J55 steel surface by 20% hydrochloric acid, proving that the ternary combination corrosion inhibitor of 1,10-phenanthroline quaternary ammonium salt, hexamethylenetetramine and 3-phenyl-2-propyn-1-ol in a mass ratio of 0.8:3.2:6.0 has a good protective effect on J55 steel.

[0159] Based on the above tests, it can be seen that the acidizing corrosion inhibitor of the present application has excellent corrosion inhibition performance at a temperature of 60-160°C, and the corrosion rate reaches the standard of SY / T 5405-2019 "Performance Test Method and Evaluation Index of Corrosion Inhibitors for Acidification", indicating that the acidizing corrosion inhibitor of the present application can significantly reduce the corrosion rate of metals.

[0160] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

[0161] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit the present application. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments can still be modified, or some or all of the technical features therein can be replaced by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the present application.

Claims

1. An acidizing corrosion inhibitor, characterized in that: It mainly contains the compound of formula i, hexamethylenetetramine and 3-phenyl-2-propyn-1-ol; The mass ratio of the compound of formula (i), hexamethylenetetramine and 3-phenyl-2-propyn-1-ol is (0.5-2.0):(0.5-4.0):(1.0-7.0); ； Formula i.

2. The acidifying corrosion inhibitor according to claim 1, characterized in that The preparation method of the compound of formula I comprises: After 1,10-phenanthroline and 2-chloroacetophenone are reacted in an organic solvent, the reaction product is subjected to rotary evaporation and vacuum drying in sequence to obtain a compound of formula I.

3. The acidifying corrosion inhibitor according to claim 2, characterized in that The molar ratio of the 1,10-phenanthroline to the 2-chloroacetophenone is 1.0:1.

1.

4. Use of the acidizing corrosion inhibitor according to any one of claims 1 to 3 in the preparation of an acidizing working fluid.

5. An acidizing working fluid, characterized in that: Contains an acidizing solution and the acidizing corrosion inhibitor according to any one of claims 1 to 3 dispersed in the acidizing solution.

6. The acidizing working fluid according to claim 5, characterized in that: The mass percentage of the acidizing corrosion inhibitor in the acidizing solution is 0.2-5 wt %.

7. The acidizing working fluid according to claim 5, characterized in that: The acidifying solution contains a hydrochloric acid solution with a mass concentration of 12-20wt%.

8. A method for preparing the acidified working fluid according to any one of claims 5 to 7, characterized in that: The method comprises: According to the composition of the acidizing working fluid according to any one of claims 5 to 7, the acidizing corrosion inhibitor component is added to the acidizing fluid and ultrasonically dissolved to obtain the acidizing working fluid.

9. Use of the acidizing working fluid according to any one of claims 5 to 7 in acidizing and corrosion inhibition treatment of oil and gas fields.

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