A method for preparing a highly efficient and environmentally friendly corrosion and scale inhibitor

Abstract

This invention relates to the field of corrosion and scale inhibitors, specifically to a method for preparing a highly efficient and environmentally friendly corrosion and scale inhibitor. The invention utilizes polyepoxysuccinic acid, sodium D-gluconate, benzotriazole, polycaprolactam-urea copolymer, zinc sulfate heptahydrate, and thiourea to formulate a highly efficient and environmentally friendly corrosion and scale inhibitor. Polyepoxysuccinic acid is an environmentally friendly green corrosion and scale inhibitor because the oxygen atoms in its polar groups contain unpaired electrons, which can act as adsorption centers in solution, thus inhibiting corrosion. Furthermore, polyepoxysuccinic acid is also a chelating agent, capable of chelating calcium ions in water, thereby inhibiting scale formation. When thiourea is combined with other agents, it can exert a synergistic effect, making the adsorption layer on the metal surface more compact and increasing the corrosion inhibition performance of the formulation. The highly efficient and environmentally friendly corrosion and scale inhibitor prepared by this invention is phosphorus-free, non-toxic, highly efficient, and environmentally friendly, possessing significant economic and utilization value.

Description

Technical Field

[0001] This invention relates to the field of corrosion and scale inhibitors, and in particular to a method for preparing a highly efficient and environmentally friendly corrosion and scale inhibitor. Background Technology

[0002] In the treatment of circulating cooling water in industries such as power, petroleum, and chemical, the addition of corrosion and scale inhibitors is often used to control scaling and corrosion in equipment and pipelines. These inhibitors effectively suppress the formation of scale such as carbonates, phosphates, and sulfates, and also provide excellent corrosion inhibition for various metal surfaces, including carbon steel and stainless steel. The main types of corrosion and scale inhibitors include inorganic polyphosphates, gluconic acid, and organic polyphosphates. These inhibitors offer advantages such as a wide range of applicable water qualities, ease of use, no need for pH adjustment, low dosage, strong scale inhibition, good corrosion inhibition, and significant water conservation.

[0003] Chinese Patent 202111130811.X discloses a highly efficient and environmentally friendly corrosion and scale inhibitor, its preparation method, and its application. The highly efficient and environmentally friendly corrosion and scale inhibitor comprises the following components in parts by weight: 2-4 parts sodium ethylenediaminetetramethylenephosphonate; 1-2 parts polymethacrylic acid; 3-6 parts polyepoxysuccinic acid; 1-2 parts copper corrosion inhibitor; and 20-22 parts solvent. The preparation method includes the following steps: Step 1), adding polymethacrylic acid and polyepoxysuccinic acid to the solvent and mixing evenly to obtain a premix; Step 2), adding sodium ethylenediaminetetramethylenephosphonate to the premix and mixing evenly to obtain a mixture; Step 3), adding the copper corrosion inhibitor to the mixture and mixing evenly to obtain the highly efficient and environmentally friendly corrosion and scale inhibitor. The highly efficient and environmentally friendly corrosion and scale inhibitor can be directly added to circulating water, with a concentration of 10-50 mg / L in the circulating water. This invention has the advantages of high efficiency, environmental friendliness, cost reduction, and convenient operation.

[0004] Chinese Patent 202211037150.0 discloses a composite corrosion and scale inhibitor, its preparation method, and its application, relating to the field of industrial circulating water treatment technology. The aforementioned composite corrosion and scale inhibitor is mainly composed of organophosphorus carboxylic acid corrosion inhibitor, polyepoxysuccinic acid, polyaspartic acid, acrylic acid copolymer, azoles, low-carbon alcohols, and water. Through the synergistic compounding of the above raw materials, the prepared composite corrosion and scale inhibitor has excellent scale inhibition and corrosion inhibition effects, effectively preventing scaling and corrosion of the condenser during the operation of the unit after industrial circulating water concentration, while achieving water saving. The composite corrosion and scale inhibitor can be widely used in the corrosion and scale inhibition treatment of industrial circulating water concentration.

[0005] Chinese Patent 202210558927.1 discloses a scale and corrosion inhibitor, which is made from the following raw materials in parts by weight: 1-5 parts polysuccinimide, 1-100 parts 2,3-diaminopropionic acid, 5-70 parts N,N-dimethylformamide, 2-50 parts deionized water, 1-3 parts sodium hydroxide, and 90-1500 parts anhydrous ethanol. This invention uses polysuccinimide and 2,3-diaminopropionic acid as raw materials to prepare a water-soluble polymer scale and corrosion inhibitor with a large number of carboxyl and amino functional groups in its structure. Even at low concentrations, it can reduce the formation of calcium sulfate scale crystals, inhibit copper corrosion, and effectively prevent scaling and corrosion.

[0006] Currently, most corrosion and scale inhibitors use phosphorus-containing formulations, with organic polyphosphates being the most widely used. However, phosphorus emissions can easily lead to eutrophication of surrounding waters, causing environmental pollution. Therefore, research on green, environmentally friendly, phosphorus-free, and highly efficient corrosion and scale inhibitors is an important future development direction for corrosion and scale inhibitors. Summary of the Invention

[0007] In view of the problems existing in the background art, the purpose of this invention is to provide a method for preparing a highly efficient and environmentally friendly corrosion and scale inhibitor.

[0008] The technical solution of the present invention is as follows:

[0009] According to a first aspect of the present invention, the present invention provides a method for preparing a highly efficient and environmentally friendly corrosion and scale inhibitor:

[0010] S1: Weigh each raw material, add deionized water, sonicate, and then transfer to the reactor;

[0011] S2: Add polyepoxysuccinic acid to the reactor, mix well, heat up, add sodium hydroxide dropwise, and control the pH.

[0012] S3: After the reaction is complete, anhydrous ethanol is added for precipitation, followed by filtration and drying to obtain a highly efficient and environmentally friendly corrosion and scale inhibitor.

[0013] According to the above preferred technical solution: each raw material is made from the following parts by weight: 10-15 parts polyepoxysuccinic acid, 8-14 parts sodium D-gluconate, 7-13 parts benzotriazole, 6-12 parts polycaprolactam-urea copolymer, 0.3-1 parts zinc sulfate heptahydrate, 10-15 parts thiourea, 45-60 parts deionized water, 2-7 parts sodium hydroxide, and 150-200 parts anhydrous ethanol.

[0014] Furthermore, the ultrasound duration is 5-10 minutes.

[0015] Furthermore, the temperature is raised to 25-40°C.

[0016] Furthermore, the sodium hydroxide has a mass concentration of 10-20%.

[0017] Furthermore, the controlled pH value is 6-8.

[0018] Furthermore, the reaction time is 2-4 hours.

[0019] According to a second aspect of the present invention, a polycaprolactam-urea copolymer is provided:

[0020] According to the mass fractions, 3-6 parts of N-vinylcaprolactam, 2-5 parts of polyethylene oxide acrylate (PEO750), and 100-120 parts of toluene are added to a high-pressure reactor. After stirring and mixing evenly at 90-100℃, 1.2-2.6 parts of 4-propenylthioaminourea, 0.8-2.2 parts of initiator, 0.04-0.2 parts of concentrated sulfuric acid, and 0.05-0.2 parts of molecular weight regulator are added. After stirring and mixing for 10-20 minutes, 0.3-1.8 parts of sodium hydroxide are added. The reaction is continued under nitrogen protection for 3-5 hours. Then, the vacuum degree is controlled at 0.08-0.1 MPa, and the reaction is continued for 2-4 hours. After completion, the temperature is lowered to 80-120℃, and the toluene is distilled off to obtain the polycaprolactam-urea copolymer.

[0021] Furthermore, the molecular weight regulator is adipic acid, terephthalic acid, isophthalic acid, or sebacic acid.

[0022] Furthermore, the initiator is azobisisobutyronitrile or benzoyl peroxide.

[0023] The principle of this invention is:

[0024] This invention synthesizes a low molecular weight polycaprolactam-polyether copolymer using N-vinylcaprolactam and polyethylene oxide acrylate, and then copolymerizes it with 4-propenylthioaminourea under the action of an initiator, grafting the aminourea segment into the molecular chain. The resulting aminourea-modified low molecular weight polycaprolactam-polyether copolymer not only has good hygroscopicity, but the introduction of aminourea into the polyurea group further enhances its corrosion inhibition ability.

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0026] 1. Polyepoxysuccinic acid is an environmentally friendly green corrosion and scale inhibitor. Because the oxygen atoms in its polar groups have unpaired electrons, these unpaired electrons can become adsorption centers in the solution, thus playing a corrosion inhibition role. In addition, polyepoxysuccinic acid is also a chelating agent, which can chelate calcium ions in water, thus playing a scale inhibition role.

[0027] 2. Sulfur dioxide is a type of surfactant-like organic compound containing polar groups. Surfactants enable these substances to adsorb at the active region of the metal-solution interface. As a result, the electrochemical reactions that would normally occur at the interface are strongly inhibited, thus greatly reducing the rate of metal surface corrosion. When combined with other agents, it can exert a synergistic effect, making the adsorption layer on the metal surface more compact and increasing the corrosion inhibition performance of the formulation.

[0028] 3. The high-efficiency and environmentally friendly corrosion and scale inhibitor prepared by this invention has a corrosion inhibition rate of 95.2% and a scale inhibition rate of 98.3%. This formula has the characteristics of being phosphorus-free, non-toxic, highly efficient, and environmentally friendly, and has important economic and utilization value. Detailed Implementation

[0029] The present invention will be further described in detail below with reference to the embodiments, but the implementation of the present invention is not limited thereto.

[0030] It should be noted that the purpose of the following embodiments is to enable those skilled in the art to understand the content of the present invention and implement it accordingly, and should not be used to limit the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

[0031] Specific embodiments of the present invention will be described in detail below. Based on these detailed descriptions, those skilled in the art will be able to clearly understand and implement the present invention. Without departing from the principles of the present invention, features in the various embodiments can be combined to obtain new implementations, or certain features in some embodiments can be substituted to obtain other preferred implementations.

[0032] The specific embodiments of this invention include the following testing methods for their corrosion inhibition and scale inhibition performance:

[0033] 1. Corrosion inhibition performance: Refer to the "National Standard of the People's Republic of China GB / T18175-2000, Determination of corrosion inhibition performance of water treatment agents - Coated plate method";

[0034] 2. Scale inhibition performance: The scale inhibition rate of the sample was determined and calculated in accordance with the standard GB / T16632-2008 "Determination of scale inhibition rate of compound corrosion and scale inhibitors by carbonate precipitation method".

[0035] Example 1

[0036] A method for preparing a highly efficient and environmentally friendly corrosion and scale inhibitor, comprising the following steps:

[0037] S1: Weigh each raw material, add deionized water, sonicate, and then transfer to the reactor;

[0038] S2: Add polyepoxysuccinic acid to the reactor, mix well, heat up, add sodium hydroxide dropwise, and control the pH.

[0039] S3: After the reaction is complete, anhydrous ethanol is added for precipitation, followed by filtration and drying to obtain a highly efficient and environmentally friendly corrosion and scale inhibitor.

[0040] The raw materials are made from the following: 10g polyepoxysuccinic acid, 8g sodium D-gluconate, 7g benzotriazole, 6g polycaprolactam-urea copolymer, 0.3g zinc sulfate heptahydrate, 10g thiourea, 45g deionized water, 2g sodium hydroxide, and 150g anhydrous ethanol.

[0041] The ultrasound duration is 5 minutes.

[0042] The temperature is raised to 25°C.

[0043] The sodium hydroxide concentration is 10%.

[0044] The controlled pH value is 6.

[0045] The reaction time is 2 hours.

[0046] The polycaprolactam-urea copolymer is prepared according to the following method:

[0047] 3g of N-vinylcaprolactam, 2g of polyethylene oxide acrylate (PEO750), and 100g of toluene were added to a high-pressure reactor. After stirring and mixing at 90°C until homogeneous, 1.2g of 4-propenylthioaminourea, 0.8g of initiator, 0.04g of concentrated sulfuric acid, and 0.05g of molecular weight regulator were added. After stirring and mixing for 10 minutes, 0.3g of sodium hydroxide was added. The reaction was continued for 3 hours under nitrogen protection. Then, the vacuum degree was controlled at 0.08MPa, and the reaction was continued for 2 hours. After completion, the temperature was lowered to 80°C, and the toluene was distilled off to obtain the polycaprolactam-urea copolymer.

[0048] The molecular weight regulator is adipic acid.

[0049] The initiator is azobisisobutyronitrile.

[0050] The corrosion and scale inhibitor prepared in this embodiment was tested and found to have a corrosion inhibition rate of 92.6% and a scale inhibition rate of 93.8%.

[0051] Example 2

[0052] A method for preparing a highly efficient and environmentally friendly corrosion and scale inhibitor, comprising the following steps:

[0053] S1: Weigh each raw material, add deionized water, sonicate, and then transfer to the reactor;

[0054] S2: Add polyepoxysuccinic acid to the reactor, mix well, heat up, add sodium hydroxide dropwise, and control the pH.

[0055] S3: After the reaction is complete, anhydrous ethanol is added for precipitation, followed by filtration and drying to obtain a highly efficient and environmentally friendly corrosion and scale inhibitor.

[0056] The raw materials are made from the following: 12g polyepoxysuccinic acid, 10g sodium D-gluconate, 9g benzotriazole, 8g polycaprolactam-urea copolymer, 0.5g zinc sulfate heptahydrate, 12g thiourea, 50g deionized water, 3g sodium hydroxide, and 160g anhydrous ethanol.

[0057] The ultrasound time is 7 minutes.

[0058] The temperature is raised to 30°C.

[0059] The sodium hydroxide concentration is 15%.

[0060] The controlled pH value is 7.

[0061] The reaction time is 3 hours.

[0062] The polycaprolactam-urea copolymer is prepared according to the following method:

[0063] 4g of N-vinylcaprolactam, 3g of polyethylene oxide acrylate (PEO750), and 105g of toluene were added to a high-pressure reactor. After stirring and mixing at 95°C until homogeneous, 1.8g of 4-propenylthioaminourea, 1.2g of initiator, 0.1g of concentrated sulfuric acid, and 0.1g of molecular weight regulator were added. After stirring and mixing for 15 minutes, 0.8g of sodium hydroxide was added. The reaction was continued for 4 hours under nitrogen protection. Then, the vacuum degree was controlled at 0.09MPa, and the reaction was continued for 3 hours. After completion, the temperature was lowered to 90°C, and the toluene was distilled off to obtain the polycaprolactam-urea copolymer.

[0064] The molecular weight regulator is terephthalic acid.

[0065] The initiator is azobisisobutyronitrile.

[0066] The corrosion and scale inhibitor prepared in this embodiment was tested and found to have a corrosion inhibition rate of 93.7% and a scale inhibition rate of 95.1%.

[0067] Example 3

[0068] A method for preparing a highly efficient and environmentally friendly corrosion and scale inhibitor, comprising the following steps:

[0069] S1: Weigh each raw material, add deionized water, sonicate, and then transfer to the reactor;

[0070] S2: Add polyepoxysuccinic acid to the reactor, mix well, heat up, add sodium hydroxide dropwise, and control the pH.

[0071] S3: After the reaction is complete, anhydrous ethanol is added for precipitation, followed by filtration and drying to obtain a highly efficient and environmentally friendly corrosion and scale inhibitor.

[0072] The raw materials are made from the following: 14g polyepoxysuccinic acid, 12g sodium D-gluconate, 11g benzotriazole, 10g polycaprolactam-urea copolymer, 0.8g zinc sulfate heptahydrate, 14g thiourea, 55g deionized water, 6g sodium hydroxide, and 180g anhydrous ethanol.

[0073] The ultrasound duration is 9 minutes.

[0074] The temperature is raised to 35°C.

[0075] The sodium hydroxide concentration is 15%.

[0076] The controlled pH value is 7.

[0077] The reaction time is 3 hours.

[0078] The polycaprolactam-urea copolymer is prepared according to the following method:

[0079] 5g of N-vinylcaprolactam, 4g of polyethylene oxide acrylate (PEO750), and 115g of toluene were added to a high-pressure reactor. After stirring and mixing at 95°C until homogeneous, 2.2g of 4-propenylthioaminourea, 1.8g of initiator, 0.15g of concentrated sulfuric acid, and 0.15g of molecular weight regulator were added. After stirring and mixing for 15 minutes, 1.5g of sodium hydroxide was added. The reaction was continued for 4 hours under nitrogen protection. Then, the vacuum degree was controlled at 0.09MPa, and the reaction was continued for 3 hours. After completion, the temperature was lowered to 110°C, and the toluene was distilled off to obtain the polycaprolactam-urea copolymer.

[0080] The molecular weight regulator is isophthalic acid.

[0081] The initiator is benzoyl peroxide.

[0082] The corrosion and scale inhibitor prepared in this embodiment was tested and found to have a corrosion inhibition rate of 95.2% and a scale inhibition rate of 98.3%.

[0083] Example 4

[0084] A method for preparing a highly efficient and environmentally friendly corrosion and scale inhibitor, comprising the following steps:

[0085] S1: Weigh each raw material, add deionized water, sonicate, and then transfer to the reactor;

[0086] S2: Add polyepoxysuccinic acid to the reactor, mix well, heat up, add sodium hydroxide dropwise, and control the pH.

[0087] S3: After the reaction is complete, anhydrous ethanol is added for precipitation, followed by filtration and drying to obtain a highly efficient and environmentally friendly corrosion and scale inhibitor.

[0088] The raw materials are made from the following: 15g polyepoxysuccinic acid, 14g sodium D-gluconate, 13g benzotriazole, 12g polycaprolactam-urea copolymer, 1g zinc sulfate heptahydrate, 15g thiourea, 60g deionized water, 7g sodium hydroxide, and 200g anhydrous ethanol.

[0089] The ultrasound duration is 10 minutes.

[0090] The temperature is raised to 40°C.

[0091] The sodium hydroxide concentration is 20%.

[0092] The controlled pH value is 8.

[0093] The reaction time is 4 hours.

[0094] The polycaprolactam-urea copolymer is prepared according to the following method:

[0095] 6g of N-vinylcaprolactam, 5g of polyethylene oxide acrylate (PEO750), and 120g of toluene were added to a high-pressure reactor. After stirring and mixing at 100℃ until homogeneous, 2.6g of 4-propenylthioaminourea, 2.2g of initiator, 0.2g of concentrated sulfuric acid, and 0.2g of molecular weight regulator were added. After stirring and mixing for 20min, 1.8g of sodium hydroxide was added. The reaction was continued for 5h under nitrogen protection, and then the vacuum degree was controlled at 0.1MPa for 4h. After completion, the temperature was lowered to 120℃, and the toluene was distilled off to obtain the polycaprolactam-urea copolymer.

[0096] The molecular weight regulator is sebacic acid.

[0097] The initiator is benzoyl peroxide.

[0098] The corrosion and scale inhibitor prepared in this embodiment was tested and found to have a corrosion inhibition rate of 94.5% and a scale inhibition rate of 96.7%.

[0099] Comparative Example 1

[0100] A method for preparing a highly efficient and environmentally friendly corrosion and scale inhibitor, comprising the following steps:

[0101] S1: Weigh each raw material, add deionized water, sonicate, and then transfer to the reactor;

[0102] S2: Add polyepoxysuccinic acid to the reactor, mix well, heat up, add sodium hydroxide dropwise, and control the pH.

[0103] S3: After the reaction is complete, anhydrous ethanol is added for precipitation, followed by filtration and drying to obtain a highly efficient and environmentally friendly corrosion and scale inhibitor.

[0104] The raw materials are made from the following: 10g polyepoxysuccinic acid, 8g sodium D-gluconate, 7g benzotriazole, 0.3g zinc sulfate heptahydrate, 10g thiourea, 45g deionized water, 2g sodium hydroxide, and 150g anhydrous ethanol.

[0105] The ultrasound duration is 5 minutes.

[0106] The temperature is raised to 25°C.

[0107] The sodium hydroxide concentration is 10%.

[0108] The controlled pH value is 6.

[0109] The reaction time is 2 hours.

[0110] The corrosion and scale inhibitor prepared in this embodiment was tested and found to have a corrosion inhibition rate of 81.6% and a scale inhibition rate of 84.9%.

[0111] Comparative Example 2

[0112] A method for preparing a highly efficient and environmentally friendly corrosion and scale inhibitor, comprising the following steps:

[0113] S1: Weigh each raw material, add deionized water, sonicate, and then transfer to the reactor;

[0114] S2: Add polyepoxysuccinic acid to the reactor, mix well, heat up, add sodium hydroxide dropwise, and control the pH.

[0115] S3: After the reaction is complete, anhydrous ethanol is added for precipitation, followed by filtration and drying to obtain a highly efficient and environmentally friendly corrosion and scale inhibitor.

[0116] The raw materials are made from the following: 8g sodium D-gluconate, 7g benzotriazole, 6g polycaprolactam-urea copolymer, 0.3g zinc sulfate heptahydrate, 10g thiourea, 45g deionized water, 2g sodium hydroxide, and 150g anhydrous ethanol.

[0117] The ultrasound duration is 5 minutes.

[0118] The temperature is raised to 25°C.

[0119] The sodium hydroxide concentration is 10%.

[0120] The controlled pH value is 6.

[0121] The reaction time is 2 hours.

[0122] The polycaprolactam-urea copolymer is prepared according to the following method:

[0123] 3g of N-vinylcaprolactam, 2g of polyethylene oxide acrylate (PEO750), and 100g of toluene were added to a high-pressure reactor. After stirring and mixing at 90°C until homogeneous, 1.2g of 4-propenylthioaminourea, 0.8g of initiator, 0.04g of concentrated sulfuric acid, and 0.05g of molecular weight regulator were added. After stirring and mixing for 10 minutes, 0.3g of sodium hydroxide was added. The reaction was continued for 3 hours under nitrogen protection. Then, the vacuum degree was controlled at 0.08MPa, and the reaction was continued for 2 hours. After completion, the temperature was lowered to 80°C, and the toluene was distilled off to obtain the polycaprolactam-urea copolymer.

[0124] The molecular weight regulator is adipic acid.

[0125] The initiator is azobisisobutyronitrile.

[0126] The corrosion and scale inhibitor prepared in this embodiment was tested and found to have a corrosion inhibition rate of 85.8% and a scale inhibition rate of 87.6%.

[0127] Comparative Example 3

[0128] A method for preparing a highly efficient and environmentally friendly corrosion and scale inhibitor, comprising the following steps:

[0129] S1: Weigh each raw material, add deionized water, sonicate, and then transfer to the reactor;

[0130] S2: Add polyepoxysuccinic acid to the reactor, mix well, heat up, add sodium hydroxide dropwise, and control the pH.

[0131] S3: After the reaction is complete, anhydrous ethanol is added for precipitation, followed by filtration and drying to obtain a highly efficient and environmentally friendly corrosion and scale inhibitor.

[0132] The raw materials are made from the following: 10g polyepoxysuccinic acid, 8g sodium D-gluconate, 7g benzotriazole, 6g polycaprolactam-urea copolymer, 0.3g zinc sulfate heptahydrate, 45g deionized water, 2g sodium hydroxide, and 150g anhydrous ethanol.

[0133] The ultrasound duration is 5 minutes.

[0134] The temperature is raised to 25°C.

[0135] The sodium hydroxide concentration is 10%.

[0136] The controlled pH value is 6.

[0137] The reaction time is 2 hours.

[0138] The polycaprolactam-urea copolymer is prepared according to the following method:

[0139] 3g of N-vinylcaprolactam, 2g of polyethylene oxide acrylate (PEO750), and 100g of toluene were added to a high-pressure reactor. After stirring and mixing at 90°C until homogeneous, 1.2g of 4-propenylthioaminourea, 0.8g of initiator, 0.04g of concentrated sulfuric acid, and 0.05g of molecular weight regulator were added. After stirring and mixing for 10 minutes, 0.3g of sodium hydroxide was added. The reaction was continued for 3 hours under nitrogen protection. Then, the vacuum degree was controlled at 0.08MPa, and the reaction was continued for 2 hours. After completion, the temperature was lowered to 80°C, and the toluene was distilled off to obtain the polycaprolactam-urea copolymer.

[0140] The molecular weight regulator is adipic acid.

[0141] The initiator is azobisisobutyronitrile.

[0142] The corrosion and scale inhibitor prepared in this embodiment was tested and found to have a corrosion inhibition rate of 88.5% and a scale inhibition rate of 90.4%.

[0143] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be used to limit the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

[0144] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the embodiments described above. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A method for preparing a highly efficient and environmentally friendly corrosion and scale inhibitor, comprising the following steps: S1: Weigh each raw material, add deionized water, sonicate, and then transfer to the reactor; add polyepoxysuccinic acid to the reactor, mix evenly, heat, add sodium hydroxide dropwise, and control the pH. S2: After the reaction is complete, anhydrous ethanol is added for precipitation, followed by filtration and drying to obtain a highly efficient and environmentally friendly corrosion and scale inhibitor. The raw materials are made from the following parts by weight: 10-15 parts polyepoxysuccinic acid, 8-14 parts sodium D-gluconate, 7-13 parts benzotriazole, 6-12 parts polycaprolactam-urea copolymer, 0.3-1 parts zinc sulfate heptahydrate, 10-15 parts thiourea, 45-60 parts deionized water, 2-7 parts sodium hydroxide, and 150-200 parts anhydrous ethanol; The polycaprolactam-urea copolymer is prepared according to the following method: 3-6 parts by mass of N-vinylcaprolactam, 2-5 parts by mass of polyethylene oxide acrylate (PEO750), and 100-120 parts by mass of toluene are added to a high-pressure reactor. After stirring and mixing at 90-100℃ until homogeneous, 1.2-2.6 parts by mass of 4-propenylthioaminourea, 0.8-2.2 parts by mass of initiator, 0.04-0.2 parts by mass of concentrated sulfuric acid, and 0.05-0.2 parts by mass of molecular weight regulator are added. After stirring and mixing for 10-20 minutes, 0.3-1.8 parts by mass of sodium hydroxide are added. The reaction is continued under nitrogen protection for 3-5 hours. Then, the vacuum degree is controlled at 0.08-0.1 MPa, and the reaction continues for 2-4 hours. After completion, the temperature is lowered to 80-120℃, and the toluene is distilled off to obtain the polycaprolactam-urea copolymer.

2. The method for preparing a highly efficient and environmentally friendly corrosion and scale inhibitor according to claim 1, characterized in that: The ultrasound time is 5-10 minutes.

3. The method for preparing a highly efficient and environmentally friendly corrosion and scale inhibitor according to claim 1, characterized in that: The temperature is raised to 25-40℃.

4. The method for preparing a highly efficient and environmentally friendly corrosion and scale inhibitor according to claim 1, characterized in that: The sodium hydroxide concentration is 10-20% by mass.

5. The method for preparing a highly efficient and environmentally friendly corrosion and scale inhibitor according to claim 1, characterized in that: The controlled pH value is 6-8.

6. The method for preparing a highly efficient and environmentally friendly corrosion and scale inhibitor according to claim 1, characterized in that: The reaction time is 2-4 hours.

7. The method for preparing a highly efficient and environmentally friendly corrosion and scale inhibitor according to claim 1, characterized in that: The molecular weight regulator is adipic acid, terephthalic acid, isophthalic acid, or sebacic acid.

8. The method for preparing a highly efficient and environmentally friendly corrosion and scale inhibitor according to claim 1, characterized in that: The initiator is azobisisobutyronitrile or benzoyl peroxide.