Stress corrosion resistant material based on slurry oil steam generator tube plate and method of making

Abstract

The application discloses an anti-stress corrosion material based on an oil slurry steam generator tube plate and a preparation method thereof, and belongs to the technical field of anti-stress corrosion material preparation. The preparation method of the anti-stress corrosion material based on the oil slurry steam generator tube plate comprises the following steps: step one, adding deionized water to a water-based polytetrafluoroethylene resin dispersion liquid, stirring and mixing, then adding a composite high-temperature stabilizer and an anti-stress corrosion agent in sequence, continuing to mix, then adding a surfactant and a coupling agent, stirring, dispersing and treating to obtain a composite coating; step two, cleaning the surface of a Q345R steel plate with ethanol, then performing sand blasting treatment, cleaning and preheating to obtain a pretreated steel plate; step three, loading the composite coating into a spray gun tank, spraying, solidifying, sintering and cooling to obtain the anti-stress corrosion material based on the oil slurry steam generator tube plate. The material prepared by the method has excellent anti-stress corrosion performance and high-temperature stability.

Description

Technical Field

[0001] This invention belongs to the field of stress corrosion resistant material preparation technology, specifically relating to stress corrosion resistant materials based on oil slurry steam generator tube sheets and their preparation methods. Background Technology

[0002] In the petroleum refining industry, the slurry steam generator, as a key piece of equipment in catalytic cracking units, has its tube sheet subjected to the combined effects of high-temperature slurry, steam, and corrosive media for extended periods. Insufficient resistance to stress corrosion has become a core issue restricting the safe and stable operation of the equipment. Traditional tube sheet materials are mainly carbon steel or low-alloy steel, whose microstructure is prone to phase transformation at high temperatures, leading to weakened grain boundaries. Active corrosive media such as sulfides, chlorides, and naphthenic acids in the slurry preferentially adsorb at grain boundary defects, forming localized corrosion cells. During equipment operation, the residual stress and thermal stress generated by the rigid fixed structure of the tube sheet, combined with the corrosive media, create a synergistic effect, easily inducing stress corrosion cracking. This cracking often propagates along grain boundaries, initially difficult to detect through conventional inspections. However, once the crack reaches a critical size, it can trigger sudden leaks, causing unplanned shutdowns or even safety accidents.

[0003] Patent CN117781763A discloses a composite aluminum strip material for preparing heat exchanger tube sheets and its preparation method, comprising an aluminum strip, a thermally conductive material, and a corrosion-resistant material; the thermally conductive material comprises polycarbonate, polyimide, and silicon carbide whiskers, with a mass ratio of 1:1:2; the corrosion-resistant material comprises polytetrafluoroethylene, perfluoroethylene propylene, and a liquid crystal polymer, with a mass ratio of 2:1:2; the thermally conductive material and the corrosion-resistant material are composite-formed on one or both sides of the aluminum strip. The composite aluminum strip material for preparing heat exchanger tube sheets provided by this invention can solve the problem that existing technologies cannot achieve optimal thermal conductivity and corrosion resistance of aluminum strips, thereby enhancing the thermal conductivity and corrosion resistance of aluminum strips and improving the service life of tube sheets in heat exchangers. Currently, although the corrosion-resistant material in this method uses polytetrafluoroethylene, perfluoroethylene propylene, and a liquid crystal polymer in a specific ratio, the materials are simply mixed, failing to form a highly synergistic and tightly bonded corrosion-resistant protection system. In complex real-world operating conditions, insufficient bonding strength between different materials can lead to the formation of tiny gaps when subjected to long-term corrosive media, providing pathways for the penetration of corrosive media. Therefore, it is necessary to further optimize corrosion-resistant material systems and composite processes. Summary of the Invention

[0004] The purpose of this invention is to provide a stress corrosion resistant material based on the tube sheet of an oil slurry steam generator and its preparation method, in order to solve the technical problem of poor stress corrosion resistance and thermal stability of tube sheet materials in the prior art.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] This invention provides a method for preparing a stress corrosion resistant material based on an oil slurry steam generator tube sheet, comprising the following steps:

[0007] Step 1: Add deionized water to the water-based polytetrafluoroethylene resin dispersion, stir and mix, then add the composite high-temperature stabilizer and stress corrosion inhibitor in sequence, continue mixing, then add the surfactant and coupling agent, stir, and disperse to obtain the composite coating;

[0008] Step 2: Clean the surface of Q345R steel plate with ethanol, then perform sandblasting, cleaning, and preheating to obtain pretreated steel plate;

[0009] Step 3: Load the composite coating into the spray gun canister, spray, cure, sinter, and cool to obtain a stress corrosion resistant material based on the oil slurry steam generator tube sheet.

[0010] Preferably, the preparation method of the composite high-temperature stabilizer includes the following steps:

[0011] Q1: Under nitrogen atmosphere, 3,5-dibromo-2-methylthiophene and anhydrous tetrahydrofuran were added to a container and stirred. Then, a hexane solution containing n-butyllithium was added and stirred to react. Trimethylchlorosilane was then added and the reaction was continued at room temperature. After the reaction was completed, distilled water was added to quench the reaction. The mixture was extracted, the organic phases were combined, washed, dried, filtered, and purified by rotary evaporation to obtain intermediate 1.

[0012] Q2: Under nitrogen atmosphere, intermediate 1 and anhydrous tetrahydrofuran were added to a container and stirred. A hexane solution containing n-butyllithium was added and stirred to obtain a mixed solution. At the same time, perfluorocyclopentene was added to anhydrous tetrahydrofuran and stirred to mix. Then, it was added to the mixed solution and reacted. The reaction was continued at room temperature. Methanol was added to quench the reaction, followed by distilled water. The organic phases were extracted, combined, washed, dried, filtered, rotary evaporated, purified, and recrystallized to obtain intermediate 2. Intermediate 2, anhydrous tetrahydrofuran, and N-bromosuccinimide were stirred at room temperature in the dark. Acetone was added to quench the reaction, and the mixture was evaporated to dryness, dissolved, washed, dried, filtered, evaporated to dryness, and recrystallized to obtain intermediate 3.

[0013] Q3: Add intermediate 3 and pyridine-4-boronic acid to a container containing tetrahydrofuran and sodium carbonate aqueous solution, stir magnetically and then introduce argon gas, then add tetra(triphenylphosphine)palladium, heat to reflux reaction, after the reaction is completed, evaporate under reduced pressure, extract, combine organic phases, wash, dry, filter under reduced pressure, evaporate to dryness, purify, and obtain composite high temperature stabilizer.

[0014] The synthesis reaction formula for the composite high-temperature stabilizer in the above process is as follows:

[0015]

[0016] The mass spectrometry analysis results of intermediate 1 were: m / z: 249.97 (100.0%), 247.97 (98.8%), 250.97 (14.8%), 248.97 (14.4%), 251.96 (7.7%), 249.96 (4.5%); the mass spectrometry analysis results of intermediate 2 were: m / z: 512.09 (100.0%), 513.10 (23.0%), 514.09 (18.8%), 513.09 (11.8%), 515.09 (5.2%), 514.10 (2.6%); the mass spectrometry analysis results of intermediate 3 were: m / z: 525.83 (100.0%), 527.83 (55.5%), 523.83. (49.1%), 526.84 (15.6%), 528.83 (9.8%), 524.84 (8.0%), 529.83 (4.5%), 526.83 (2.3%), 527.84 (1.2%); The mass spectrometry analysis results of the composite high-temperature stabilizer are: m / z: 522.07 (100.0%), 523.07 (28.8%), 524.06 (9.1%), 524.07 (4.1%), 525.07 (2.5%).

[0017] Preferably, in Q1, the ratio of 3,5-dibromo-2-methylthiophene, anhydrous tetrahydrofuran, n-butyllithium, n-hexane, and trimethylchlorosilane is (30-45) g : (300-500) mL : (8.12-8.42) g : (50.2-52.8) mL : (15.88-17.26) mL. The mixture is stirred and cooled to -78°C. The stirring reaction is carried out at -78°C for 20-30 min, and the reaction is continued for 10-12 h.

[0018] Preferably, in Q2, the ratio of intermediate 1, n-butyllithium, n-hexane, and perfluorocyclopentene is (20.08-24.12) g : (5.82-6.04) g : (32-43) mL : (5.34-6.48) mL, stirred and cooled to -78°C, with the stirring temperature at -78°C for 50-60 min, the reaction temperature at -78°C for 2-4 h, and the reaction time continued at room temperature for 10-12 h; the ratio of intermediate 2, anhydrous tetrahydrofuran, and N-bromosuccinimide is (13.88-14.16) mL : (220-280) mL : (10.12-10.81) g, and the stirring reaction time is 14-18 h.

[0019] Preferably, in Q3, the ratio of intermediate 3, pyridine-4-boronic acid, tetrahydrofuran, sodium carbonate aqueous solution, and tetra(triphenylphosphine)palladium is (10-18.88) g : (5.14-6.78) g : (100-180) mL : (150-220) mL : (0.147-0.322) g, the sodium carbonate aqueous solution has a mass fraction of 20 wt%, the heating reflux temperature is 70-80℃, and the time is 10-12 h.

[0020] Preferably, the method for preparing the stress corrosion resistant agent includes the following steps:

[0021] S1: Thiourea and potassium carbonate were added to ethanol and stirred. Then, ethanol containing dissolved carbon disulfide was added, and the mixture was heated to reflux. After the reaction was completed, the mixture was rotary evaporated, distilled water was added, stirred, acidified, filtered, and washed to obtain product a. 4-(trifluoromethoxy)benzoic acid, HATU, N,N-dimethylformamide, and N,N-diisopropylethylamine were added to a container, mixed and stirred, and then product a was added. The mixture was stirred at room temperature and reacted. After the reaction was completed, the mixture was added to distilled water, filtered, washed, filtered again, and dried to obtain product b.

[0022] S2: 5-Trifluoromethylindole and N,N-dimethylformamide were added to a container, followed by sodium hydride. After stirring, epoxybromopropane was added, and the mixture was heated under reflux. After the reaction was completed, the mixture was cooled, distilled water was added, and the mixture was extracted, washed, dried, and rotary evaporated to obtain product c.

[0023] S3: Add product c, N,N-dimethylformamide and potassium carbonate to a container, stir, add product b, heat to reflux and react. After the reaction is complete, cool, add distilled water, extract, wash, dry, filter, rotary evaporate, and purify to obtain the stress corrosion resistant agent.

[0024] The synthesis reaction formula for the stress corrosion inhibitor in the above process is as follows:

[0025]

[0026] The mass spectrometry analysis results for product a were: m / z: 132.98 (100.0%), 134.97 (9.1%), 133.98 (3.8%), 133.97 (1.1%); for product b: m / z: 320.99 (100.0%), 321.99 (11.0%), 322.98 (9.1%), 321.98 (2.7%), 322.99 (1.3%), 323.98 (1.2%); for product c: m / z: 241.07 (100.0%), 242.07 (13.3%), 243.08 (1.0%); and for the stress corrosion inhibitor: m / z: 562.06. (100.0%), 563.06 (25.7%), 564.05 (9.1%), 564.06 (4.1%), 565.06 (2.4%), 563.05 (1.5%).

[0027] Preferably, in S1, the ratio of aminothiourea, potassium carbonate, and carbon disulfide is (0.628-0.742) g : (1.623-1.667) g : (0.101-0.112) g, and the mixture is stirred for 10-20 min, heated to reflux at 40-50℃ for 4-6 h; the ratio of 4-(trifluoromethoxy)benzoic acid, HATU, N,N-dimethylformamide, N,N-diisopropylethylamine, and product a is (0.517-0.605) g : (1.012-1.042) g : (15-20) mL : (0.562-0.604) g : (0.312-0.357) g, and the mixture is stirred for 20-30 min, and the reaction time is 10-12 h at room temperature.

[0028] Preferably, in step S2, the ratio of 5-trifluoromethylindole, N,N-dimethylformamide, sodium hydride, and epichlorohydrin is (0.261-0.311) g : (10-18) mL : (0.09-0.13) g : (0.608-0.647) g. After stirring for 10-20 min, epichlorohydrin is added, and the reaction is heated to reflux at 40-50°C for 10-12 h. In step S3, the ratio of product c, N,N-dimethylformamide, potassium carbonate, and product b is (0.388-0.446) g : (18-22) mL : (0.688-0.742) g : (0.688-0.748) g. The stirring time is 20-25 min, and the reaction is heated to reflux at 75-80°C for 10-12 h.

[0029] Preferably, in step one, the ratio of water-based polytetrafluoroethylene resin dispersion, deionized water, composite high-temperature stabilizer, stress corrosion inhibitor, surfactant and coupling agent is (70-85) g : (20-40) mL : (10-15) g : (8-14) g : (2.4-4.3) g : (1.1-1.5) g.

[0030] As a preferred option, the stress corrosion resistant material based on the oil slurry steam generator tube sheet is prepared using the above-described preparation method.

[0031] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0032] 1. The present invention applies the prepared composite high-temperature stabilizer and stress corrosion inhibitor to the stress corrosion resistant material based on the tube sheet of the oil slurry steam generator, which can effectively improve its high-temperature stability and stress corrosion cracking resistance.

[0033] 2. This invention applies the prepared composite high-temperature stabilizer to stress corrosion resistant materials based on oil slurry steam generator tube sheets, effectively improving its high-temperature stability and resistance to stress corrosion cracking. The perfluorocyclopentene fragment contained in the composite high-temperature stabilizer has an excellent stable structure with high carbon-fluorine bond energy, short bond length, and strong molecular cohesion, ensuring that the stabilizer itself will not degrade or fail under the high-temperature and high-pressure steam environment of the oil slurry steam generator, and can continue to function for a long time, preventing high-temperature oxidation and creep of the material matrix. The perfluorinated fragment contained in the composite high-temperature stabilizer has strong hydrophobic and oleophobic properties, effectively repelling water molecules and corrosive ions, preventing them from reaching the metal surface, and cutting off the electrochemical corrosion path. The contained pyridine group acts as an excellent organic corrosion inhibitor, and the nitrogen atom lone pair electrons can be strongly adsorbed on the metal surface to form a dense monomolecular protective film, isolating the corrosive medium and increasing the hydrogen evolution overpotential of the metal surface, significantly inhibiting anodic dissolution and hydrogen-induced cracking.

[0034] 3. This invention applies the prepared stress corrosion inhibitor to stress corrosion resistant materials based on oil slurry steam generator tube sheets, which can effectively improve its protective performance. The thiadiazole and indole groups contained in the stress corrosion inhibitor are rich in sulfur and nitrogen heteroatoms, which can provide lone pairs of electrons and form strong coordination bonds with the empty d orbitals of the tube sheet metal. They are chemically adsorbed onto the metal surface to form a dense and firm monomolecular protective film, which effectively isolates the metal matrix from the corrosive medium, significantly inhibits the anodic metal dissolution reaction, and prevents the initiation of corrosion pits. The introduced trifluoromethyl and trifluoromethoxy groups can form a superhydrophobic barrier on the matrix surface, effectively repelling high-temperature water vapor, condensate, and organic polar substances in the oil slurry, preventing them from contacting the matrix surface, inhibiting electrochemical corrosion, and also improving its chemical and thermal stability, making it difficult to be oxidized or decomposed in high-temperature environments. At the same time, the dense adsorption film directly inhibits the anodic process, and the sulfur and nitrogen-containing heterocyclic compounds can poison the hydrogen evolution reaction, increase the hydrogen evolution overpotential, reduce the generation and penetration of hydrogen atoms, and prevent hydrogen-induced cracking. Detailed Implementation

[0035] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] Example 1: This example discloses a method for preparing a composite high-temperature stabilizer, including the following steps:

[0037] Q1: Under nitrogen atmosphere, 37.5 g of 3,5-dibromo-2-methylthiophene and 400 mL of anhydrous tetrahydrofuran were added to a container, stirred and cooled to -78 °C, 51.5 mL of hexane solution containing 8.27 g of n-butyllithium was added, and the mixture was stirred at -78 °C for 20 min. Then, 16.54 mL of trimethylchlorosilane was added, and the reaction was continued at room temperature for 12 h. After the reaction was completed, distilled water was added to quench the reaction, and the mixture was extracted, the organic phases were combined, washed, dried, filtered, and purified by rotary evaporation to obtain intermediate 1.

[0038] Q2: Under nitrogen atmosphere, 22.11 g of intermediate 1 and 300 mL of anhydrous tetrahydrofuran were added to a container, stirred and cooled to -78 °C. 37.5 mL of hexane solution containing 5.93 g of n-butyllithium was added, and the mixture was stirred at -78 °C for 50 min to obtain a mixed solution. At the same time, 5.92 mL of perfluorocyclopentene was added to 80 mL of anhydrous tetrahydrofuran, stirred and mixed, and then added to the mixed solution. The reaction was carried out at -78 °C for 2 h, and then continued at room temperature for 12 h. Methanol was added to quench the reaction, followed by distilled water, extraction, and combining of organic phases. The mixture was washed, dried, filtered, rotary evaporated, purified, and recrystallized to obtain intermediate 2. 13.98 mL of intermediate 2, 250 mL of anhydrous tetrahydrofuran, and 10.41 g of N-bromosuccinimide were stirred at room temperature in the dark for 16 h. Acetone was added to quench the reaction, and the mixture was evaporated to dryness, dissolved, washed, dried, filtered, evaporated to dryness, and recrystallized to obtain intermediate 3.

[0039] Q3: 14.44 g of intermediate 3 and 5.91 g of pyridine-4-boronic acid were added to a container containing 140 mL of tetrahydrofuran and 185 mL of sodium carbonate aqueous solution with a mass fraction of 20 wt%. After magnetic stirring, argon gas was introduced, and then 0.235 g of tetra(triphenylphosphine)palladium was added. The mixture was heated to reflux at 75 °C for 12 h. After the reaction was completed, the mixture was evaporated under reduced pressure, extracted, and the organic phases were combined, washed, dried, filtered under reduced pressure, evaporated to dryness, and purified to obtain the composite high-temperature stabilizer.

[0040] This embodiment discloses a method for preparing a stress corrosion resistant agent, including the following steps:

[0041] S1: 0.685 g of aminothiourea and 1.645 g of potassium carbonate were added to 15 mL of ethanol and stirred for 15 min. Then, 8 mL of ethanol containing 0.106 g of carbon disulfide was added, and the mixture was heated to reflux at 45 °C for 6 h. After the reaction was completed, the mixture was rotary evaporated, distilled water was added, stirred, acidified, filtered, and washed to obtain product a. 0.562 g of 4-(trifluoromethoxy)benzoic acid, 1.027 g of HATU, 17.5 mL of N,N-dimethylformamide, and 0.583 g of N,N-diisopropylethylamine were added to a container and stirred for 20 min. Then, 0.335 g of product a was added, and the mixture was stirred at room temperature for 10 h. After the reaction was completed, the mixture was added to distilled water, filtered, washed, filtered again, and dried to obtain product b.

[0042] S2: 0.281 g of 5-trifluoromethylindole and 14 mL of N,N-dimethylformamide were added to a container, followed by 0.11 g of sodium hydride. After stirring for 10 min, 0.628 g of epichlorohydrin was added. The mixture was heated to reflux at 45 °C for 12 h. After the reaction was completed, the mixture was cooled, distilled water was added, and the mixture was extracted, washed, dried, and rotary evaporated to obtain product c.

[0043] S3: Add 0.412g of product c, 20mL of N,N-dimethylformamide and 0.715g of potassium carbonate to a container, stir, add 0.718g of product b, heat to reflux at 75℃ for 12h, after the reaction is completed, cool, add distilled water, extract, wash, dry, filter, rotary evaporate, and purify to obtain stress corrosion resistant agent.

[0044] This embodiment discloses a method for preparing a stress corrosion resistant material based on an oil slurry steam generator tube sheet, including the following steps:

[0045] Step 1: Add 30 mL of deionized water to 77.5 g of water-based polytetrafluoroethylene resin dispersion, stir and mix, then add 12.5 g of composite high-temperature stabilizer and 11 g of stress corrosion inhibitor in sequence, continue mixing, then add 5.3 g of surfactant and 1.3 g of silane coupling agent KH-550, stir at 1500 rpm for 1 h, and disperse for 30 min to obtain composite coating;

[0046] Step 2: Clean the surface of Q345R steel plate with ethanol, then perform sandblasting, cleaning, and preheat at 100℃ for 10 minutes to obtain pretreated steel plate;

[0047] Step 3: Load the composite coating into the spray gun canister, spray, cure, sinter, and cool to obtain a stress corrosion resistant material based on the oil slurry steam generator tube sheet.

[0048] Example 2: This example discloses a method for preparing a composite high-temperature stabilizer, including the following steps:

[0049] Q1: Under nitrogen atmosphere, 30g of 3,5-dibromo-2-methylthiophene and 300mL of anhydrous tetrahydrofuran were added to a container, stirred and cooled to -78℃, 50.2mL of hexane solution containing 8.12g of n-butyllithium was added, and the mixture was stirred at -78℃ for 20min. Then, 15.88mL of trimethylchlorosilane was added, and the reaction was continued at room temperature for 12h. After the reaction was completed, distilled water was added to quench the reaction, and the mixture was extracted, the organic phases were combined, washed, dried, filtered, and purified by rotary evaporation to obtain intermediate 1.

[0050] Q2: Under nitrogen atmosphere, 20.08 g of intermediate 1 and 300 mL of anhydrous tetrahydrofuran were added to a container, stirred and cooled to -78 °C. 32 mL of hexane solution containing 5.82 g of n-butyllithium was added, and the mixture was stirred at -78 °C for 50 min to obtain a mixed solution. At the same time, 5.34 mL of perfluorocyclopentene was added to 80 mL of anhydrous tetrahydrofuran, stirred and mixed, and then added to the mixed solution. The reaction was carried out at -78 °C for 2 h, and then continued at room temperature for 12 h. Methanol was added to quench the reaction, followed by distilled water, extraction, combining the organic phases, washing, drying, filtering, rotary evaporation, purification, and recrystallization to obtain intermediate 2. 13.88 mL of intermediate 2, 220 mL of anhydrous tetrahydrofuran and 10.12 g of N-bromosuccinimide were stirred at room temperature in the dark for 16 h. Acetone was added to quench the reaction, and the mixture was evaporated to dryness, dissolved, washed, dried, filtered, evaporated to dryness, and recrystallized to obtain intermediate 3.

[0051] Q3: 10g of intermediate 3 and 5.14g of pyridine-4-boronic acid were added to a container containing 100mL of tetrahydrofuran and 150mL of sodium carbonate aqueous solution with a mass fraction of 20wt%. After magnetic stirring, argon gas was introduced, and then 0.147g of tetra(triphenylphosphine)palladium was added. The mixture was heated to reflux at 75℃ for 12h. After the reaction was completed, the mixture was evaporated under reduced pressure, extracted, and the organic phases were combined, washed, dried, filtered under reduced pressure, evaporated to dryness, and purified to obtain the composite high-temperature stabilizer.

[0052] This embodiment discloses a method for preparing a stress corrosion resistant agent, including the following steps:

[0053] S1: 0.628 g of aminothiourea and 1.623 g of potassium carbonate were added to 15 mL of ethanol and stirred for 15 min. Then, 8 mL of ethanol containing 0.101 g of carbon disulfide was added, and the mixture was heated to reflux at 45 °C for 6 h. After the reaction was completed, the mixture was rotary evaporated, distilled water was added, stirred, acidified, filtered, and washed to obtain product a. 0.517 g of 4-(trifluoromethoxy)benzoic acid, 1.012 g of HATU, 15 mL of N,N-dimethylformamide, and 0.562 g of N,N-diisopropylethylamine were added to a container and stirred for 20 min. Then, 0.312 g of product a was added, and the mixture was stirred at room temperature for 10 h. After the reaction was completed, the mixture was added to distilled water, filtered, washed, filtered again, and dried to obtain product b.

[0054] S2: 0.261 g of 5-trifluoromethylindole and 18 mL of N,N-dimethylformamide were added to a container, followed by 0.13 g of sodium hydride. After stirring for 10 min, 0.608 g of epichlorohydrin was added. The mixture was heated to reflux at 45 °C for 12 h. After the reaction was completed, the mixture was cooled, distilled water was added, and the mixture was extracted, washed, dried, and rotary evaporated to obtain product c.

[0055] S3: Add 0.388g of product c, 18mL of N,N-dimethylformamide and 0.688g of potassium carbonate to a container, stir, then add 0.688g of product b, heat to reflux at 75℃ for 12h. After the reaction is complete, cool, add distilled water, extract, wash, dry, filter, rotary evaporate, and purify to obtain the stress corrosion resistant agent.

[0056] This embodiment discloses a method for preparing a stress corrosion resistant material based on an oil slurry steam generator tube sheet, including the following steps:

[0057] Step 1: Add 20mL of deionized water to 70g of water-based polytetrafluoroethylene resin dispersion, stir and mix, then add 15g of composite high temperature stabilizer and 8g of stress corrosion inhibitor in sequence, continue mixing, then add 2.4g of surfactant and 1.1g of silane coupling agent KH-550, stir at 1500rpm for 1h, and disperse for 30min to obtain composite coating;

[0058] Step 2: Clean the surface of Q345R steel plate with ethanol, then perform sandblasting, cleaning, and preheat at 100℃ for 10 minutes to obtain pretreated steel plate;

[0059] Step 3: Load the composite coating into the spray gun canister, spray, cure, sinter, and cool to obtain a stress corrosion resistant material based on the oil slurry steam generator tube sheet.

[0060] Example 3: This example discloses a method for preparing a composite high-temperature stabilizer, including the following steps:

[0061] Q1: Under nitrogen atmosphere, 45g of 3,5-dibromo-2-methylthiophene and 500mL of anhydrous tetrahydrofuran were added to a container, stirred and cooled to -78℃, 52.8mL of hexane solution containing 8.42g of n-butyllithium was added, and the mixture was stirred at -78℃ for 20min. Then, 17.26mL of trimethylchlorosilane was added, and the reaction was continued at room temperature for 12h. After the reaction was completed, distilled water was added to quench the reaction, and the mixture was extracted, the organic phases were combined, washed, dried, filtered, and purified by rotary evaporation to obtain intermediate 1.

[0062] Q2: Under nitrogen atmosphere, 24.12 g of intermediate 1 and 300 mL of anhydrous tetrahydrofuran were added to a container, stirred and cooled to -78 °C. 43 mL of hexane solution containing 6.04 g of n-butyllithium was added, and the mixture was stirred at -78 °C for 50 min to obtain a mixed solution. At the same time, 6.48 mL of perfluorocyclopentene was added to 80 mL of anhydrous tetrahydrofuran, stirred and mixed, and then added to the mixed solution. The reaction was carried out at -78 °C for 2 h, and then continued at room temperature for 12 h. The reaction was quenched with methanol, and then distilled water was added for extraction. The organic phases were combined, washed, dried, filtered, rotary evaporated, purified, and recrystallized to obtain intermediate 2. 14.16 mL of intermediate 2, 280 mL of anhydrous tetrahydrofuran and 10.81 g of N-bromosuccinimide were stirred at room temperature in the dark for 16 h. The reaction was quenched with acetone, evaporated to dryness, dissolved, washed, dried, filtered, evaporated to dryness, and recrystallized to obtain intermediate 3.

[0063] Q3: 18.88 g of intermediate 3 and 6.78 g of pyridine-4-boronic acid were added to a container containing 180 mL of tetrahydrofuran and 220 mL of sodium carbonate aqueous solution with a mass fraction of 20 wt%. After magnetic stirring, argon gas was introduced, and then 0.322 g of tetra(triphenylphosphine)palladium was added. The mixture was heated to reflux at 75 °C for 12 h. After the reaction was completed, the mixture was extracted by rotary evaporation under reduced pressure. The organic phases were combined, washed, dried, filtered under reduced pressure, and then evaporated to dryness to obtain a composite high-temperature stabilizer.

[0064] This embodiment discloses a method for preparing a stress corrosion resistant agent, including the following steps:

[0065] S1: 0.742 g of aminothiourea and 1.667 g of potassium carbonate were added to 15 mL of ethanol and stirred for 15 min. Then, 8 mL of ethanol containing 0.112 g of carbon disulfide was added, and the mixture was heated to reflux at 45 °C for 6 h. After the reaction was completed, the mixture was rotary evaporated, distilled water was added, stirred, acidified, filtered, and washed to obtain product a. 0.605 g of 4-(trifluoromethoxy)benzoic acid, 1.042 g of HATU, 20 mL of N,N-dimethylformamide, and 0.604 g of N,N-diisopropylethylamine were added to a container and stirred for 20 min. Then, 0.357 g of product a was added, and the mixture was stirred at room temperature for 10 h. After the reaction was completed, the mixture was added to distilled water, filtered, washed, filtered again, and dried to obtain product b.

[0066] S2: 0.311 g of 5-trifluoromethylindole and 10 mL of N,N-dimethylformamide were added to a container, followed by 0.09 g of sodium hydride. After stirring for 10 min, 0.647 g of epichlorohydrin was added. The mixture was heated to reflux at 45 °C for 12 h. After the reaction was completed, the mixture was cooled, distilled water was added, and the mixture was extracted, washed, dried, and rotary evaporated to obtain product c.

[0067] S3: Add 0.446g of product c, 19mL of N,N-dimethylformamide and 0.742g of potassium carbonate to a container, stir, add 0.748g of product b, heat to reflux at 75℃ for 12h, after the reaction is completed, cool, add distilled water, extract, wash, dry, filter, rotary evaporate, and purify to obtain stress corrosion resistant agent.

[0068] This embodiment discloses a method for preparing a stress corrosion resistant material based on an oil slurry steam generator tube sheet, including the following steps:

[0069] Step 1: Add 40mL of deionized water to 85g of water-based polytetrafluoroethylene resin dispersion, stir and mix, then add 10g of composite high temperature stabilizer and 14g of stress corrosion inhibitor in sequence, continue mixing, then add 4.3g of surfactant and 1.5g of silane coupling agent KH-550, stir at 1500rpm for 1h, and disperse for 30min to obtain composite coating;

[0070] Step 2: Clean the surface of Q345R steel plate with ethanol, then perform sandblasting, cleaning, and preheat at 100℃ for 10 minutes to obtain pretreated steel plate;

[0071] Step 3: Load the composite coating into the spray gun canister, spray, cure, sinter, and cool to obtain a stress corrosion resistant material based on the oil slurry steam generator tube sheet.

[0072] Example 4: This example discloses a method for preparing a composite high-temperature stabilizer, including the following steps:

[0073] Q1: Under nitrogen atmosphere, 32g of 3,5-dibromo-2-methylthiophene and 350mL of anhydrous tetrahydrofuran were added to a container, stirred and cooled to -78℃, 50.8mL of hexane solution containing 8.17g of n-butyllithium was added, and the mixture was stirred at -78℃ for 20min. Then, 16.21mL of trimethylchlorosilane was added, and the reaction was continued at room temperature for 12h. After the reaction was completed, distilled water was added to quench the reaction, and the mixture was extracted, the organic phases were combined, washed, dried, filtered, and purified by rotary evaporation to obtain intermediate 1.

[0074] Q2: Under nitrogen atmosphere, 21.18 g of intermediate 1 and 300 mL of anhydrous tetrahydrofuran were added to a container, stirred and cooled to -78°C. 35 mL of hexane solution containing 5.87 g of n-butyllithium was added, and the mixture was stirred at -78°C for 50 min to obtain a mixed solution. At the same time, 5.63 mL of perfluorocyclopentene was added to 80 mL of anhydrous tetrahydrofuran, stirred and mixed, and then added to the mixed solution. The reaction was carried out at -78°C for 2 h, and then continued at room temperature for 12 h. The reaction was quenched with methanol, and then distilled water was added for extraction. The organic phases were combined, washed, dried, filtered, rotary evaporated, purified, and recrystallized to obtain intermediate 2. 14.08 mL of intermediate 2, 230 mL of anhydrous tetrahydrofuran and 10.27 g of N-bromosuccinimide were stirred at room temperature in the dark for 16 h. The reaction was quenched with acetone, evaporated to dryness, dissolved, washed, dried, filtered, evaporated to dryness, and recrystallized to obtain intermediate 3.

[0075] Q3: 12.22 g of intermediate 3 and 5.52 g of pyridine-4-boronic acid were added to a container containing 120 mL of tetrahydrofuran and 170 mL of sodium carbonate aqueous solution with a mass fraction of 20 wt%. After magnetic stirring, argon gas was introduced, and then 0.188 g of tetra(triphenylphosphine)palladium was added. The mixture was heated to reflux at 75 °C for 12 h. After the reaction was completed, the mixture was evaporated under reduced pressure, extracted, and the organic phases were combined, washed, dried, filtered under reduced pressure, evaporated to dryness, and purified to obtain the composite high-temperature stabilizer.

[0076] This embodiment discloses a method for preparing a stress corrosion resistant agent, including the following steps:

[0077] S1: 0.657 g of aminothiourea and 1.637 g of potassium carbonate were added to 15 mL of ethanol and stirred for 15 min. Then, 8 mL of ethanol containing 0.103 g of carbon disulfide was added, and the mixture was heated to reflux at 45 °C for 6 h. After the reaction was completed, the mixture was rotary evaporated, distilled water was added, stirred, acidified, filtered, and washed to obtain product a. 0.538 g of 4-(trifluoromethoxy)benzoic acid, 1.018 g of HATU, 16 mL of N,N-dimethylformamide, and 0.572 g of N,N-diisopropylethylamine were added to a container and stirred for 20 min. Then, 0.328 g of product a was added, and the mixture was stirred at room temperature for 10 h. After the reaction was completed, the mixture was added to distilled water, filtered, washed, filtered again, and dried to obtain product b.

[0078] S2: 0.276 g of 5-trifluoromethylindole and 12 mL of N,N-dimethylformamide were added to a container, followed by 0.1 g of sodium hydride. After stirring for 10 min, 0.618 g of epichlorohydrin was added. The mixture was heated to reflux at 45 °C for 12 h. After the reaction was completed, the mixture was cooled, distilled water was added, and the mixture was extracted, washed, dried, and rotary evaporated to obtain product c.

[0079] S3: Add 0.399g of product c, 21mL of N,N-dimethylformamide and 0.698g of potassium carbonate to a container, stir, add 0.738g of product b, heat to reflux at 75℃ for 12h, after the reaction is complete, cool, add distilled water, extract, wash, dry, filter, rotary evaporate, and purify to obtain stress corrosion resistant agent.

[0080] This embodiment discloses a method for preparing a stress corrosion resistant material based on an oil slurry steam generator tube sheet, including the following steps:

[0081] Step 1: Add 25mL of deionized water to 75g of water-based polytetrafluoroethylene resin dispersion, stir and mix, then add 11g of composite high temperature stabilizer and 10g of stress corrosion inhibitor in sequence, continue mixing, then add 2.8g of surfactant and 1.2g of silane coupling agent KH-550, stir at 1500rpm for 1h, and disperse for 30min to obtain composite coating;

[0082] Step 2: Clean the surface of Q345R steel plate with ethanol, then perform sandblasting, cleaning, and preheat at 100℃ for 10 minutes to obtain pretreated steel plate;

[0083] Step 3: Load the composite coating into the spray gun canister, spray, cure, sinter, and cool to obtain a stress corrosion resistant material based on the oil slurry steam generator tube sheet.

[0084] Comparative Example 1: Compared with Example 1, Comparative Example 1 did not add a composite high-temperature stabilizer during the preparation of stress corrosion resistant material based on oil slurry steam generator tube sheet, and all other conditions remained unchanged.

[0085] Comparative Example 2: Compared with Example 1, Comparative Example 2 did not add stress corrosion inhibitors during the preparation of stress corrosion resistant materials based on oil slurry steam generator tube sheets, and all other conditions remained unchanged.

[0086] Performance testing:

[0087] The stress corrosion resistant materials based on the oil slurry steam generator tube sheet prepared according to Examples 1-4 and Comparative Examples 1-2 were subjected to performance tests. The high-temperature performance of the samples was tested according to GB / T 228.2-2015 at a test temperature of 400℃, and the stress corrosion cracking resistance of the samples was tested according to GB / T4157-2017. The test results are shown in Table 1.

[0088] Table 1

[0089]

[0090] As shown in Table 1, the test results demonstrate that the methods described in Examples 1-4 effectively improve the high-temperature stability and stress corrosion resistance of the prepared oil slurry steam generator tube sheet. A comparison between Comparative Example 1 and Examples 1-4 reveals that adding a composite high-temperature stabilizer effectively enhances the high-temperature stability and stress corrosion resistance of the samples. Similarly, a comparison between Comparative Example 2 and Examples 1-4 shows that adding a stress corrosion inhibitor effectively improves the high-temperature stability and stress corrosion resistance of the samples.

[0091] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

[0092] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to specific implementations. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A method for preparing stress corrosion resistant materials based on tube sheets of oil slurry steam generators, characterized in that, Includes the following steps: Step 1: Add deionized water to the water-based polytetrafluoroethylene resin dispersion, stir and mix, then add the composite high-temperature stabilizer and stress corrosion inhibitor in sequence, continue mixing, then add the surfactant and coupling agent, stir, and disperse to obtain the composite coating; Step 2: Clean the surface of Q345R steel plate with ethanol, then perform sandblasting, cleaning, and preheating to obtain pretreated steel plate; Step 3: Load the composite coating into the spray gun canister, spray, cure, sinter, and cool to obtain a stress corrosion resistant material based on the oil slurry steam generator tube sheet; The preparation method of the composite high-temperature stabilizer includes the following steps: Q1: Under nitrogen atmosphere, 3,5-dibromo-2-methylthiophene and anhydrous tetrahydrofuran were added to a container and stirred. Then, a hexane solution containing n-butyllithium was added and stirred to react. Trimethylchlorosilane was then added and the reaction was continued at room temperature. After the reaction was completed, distilled water was added to quench the reaction. The mixture was extracted, the organic phases were combined, washed, dried, filtered, and purified by rotary evaporation to obtain intermediate 1. Q2: Under nitrogen atmosphere, intermediate 1 and anhydrous tetrahydrofuran were added to a container and stirred. A hexane solution containing n-butyllithium was added and stirred to obtain a mixed solution. At the same time, perfluorocyclopentene was added to anhydrous tetrahydrofuran and stirred to mix. Then, it was added to the mixed solution and reacted. The reaction was continued at room temperature. Methanol was added to quench the reaction, followed by distilled water. The organic phases were extracted, combined, washed, dried, filtered, rotary evaporated, purified, and recrystallized to obtain intermediate 2. Intermediate 2, anhydrous tetrahydrofuran, and N-bromosuccinimide were stirred at room temperature in the dark. Acetone was added to quench the reaction, and the mixture was evaporated to dryness, dissolved, washed, dried, filtered, evaporated to dryness, and recrystallized to obtain intermediate 3. Q3: Add intermediate 3 and pyridine-4-boronic acid to a container containing tetrahydrofuran and sodium carbonate aqueous solution, stir magnetically and then introduce argon gas. Then add tetra(triphenylphosphine)palladium and heat to reflux. After the reaction is completed, evaporate under reduced pressure, extract, combine organic phases, wash, dry, filter under reduced pressure, evaporate to dryness, and purify to obtain a composite high temperature stabilizer. The method for preparing the stress corrosion resistant agent includes the following steps: S1: Thiourea and potassium carbonate were added to ethanol and stirred. Then, ethanol containing dissolved carbon disulfide was added, and the mixture was heated to reflux. After the reaction was completed, the mixture was rotary evaporated, distilled water was added, stirred, acidified, filtered, and washed to obtain product a. 4-(trifluoromethoxy)benzoic acid, HATU, N,N-dimethylformamide, and N,N-diisopropylethylamine were added to a container, mixed and stirred, and then product a was added. The mixture was stirred at room temperature and reacted. After the reaction was completed, the mixture was added to distilled water, filtered, washed, filtered again, and dried to obtain product b. S2: 5-Trifluoromethylindole and N,N-dimethylformamide were added to a container, followed by sodium hydride. After stirring, epoxybromopropane was added, and the mixture was heated under reflux. After the reaction was completed, the mixture was cooled, distilled water was added, and the mixture was extracted, washed, dried, and rotary evaporated to obtain product c. S3: Add product c, N,N-dimethylformamide and potassium carbonate to a container, stir, add product b, heat to reflux and react. After the reaction is complete, cool, add distilled water, extract, wash, dry, filter, rotary evaporate, and purify to obtain the stress corrosion resistant agent.

2. The method for preparing stress corrosion resistant material based on oil slurry steam generator tube sheet according to claim 1, characterized in that, In Q1, the ratio of the amounts of 3,5-dibromo-2-methylthiophene, anhydrous tetrahydrofuran, n-butyllithium, n-hexane, and trimethylchlorosilane is (30-45) g : (300-500) mL : (8.12-8.42) g : (50.2-52.8) mL : (15.88-17.26) mL.

3. The method for preparing stress corrosion resistant material based on oil slurry steam generator tube sheet according to claim 1, characterized in that, In Q2, the ratio of intermediate 1, n-butyllithium, n-hexane, and perfluorocyclopentene is (20.08-24.12) g : (5.82-6.04) g : (32-43) mL : (5.34-6.48) mL; the ratio of intermediate 2, anhydrous tetrahydrofuran, and N-bromosuccinimide is (13.88-14.16) mL : (220-280) mL : (10.12-10.81) g.

4. The method for preparing stress corrosion resistant material based on oil slurry steam generator tube sheet according to claim 1, characterized in that, In Q3, the ratio of intermediate 3, pyridine-4-boronic acid, tetrahydrofuran, sodium carbonate aqueous solution and tetra(triphenylphosphine)palladium is (10-18.88) g : (5.14-6.78) g : (100-180) mL : (150-220) mL : (0.147-0.322) g.

5. The method for preparing stress corrosion resistant material based on oil slurry steam generator tube sheet according to claim 1, characterized in that, In S1, the ratio of aminothiourea, potassium carbonate, and carbon disulfide is (0.628-0.742) g : (1.623-1.667) g : (0.101-0.112) g; the ratio of 4-(trifluoromethoxy)benzoic acid, HATU, N,N-dimethylformamide, N,N-diisopropylethylamine, and product a is (0.517-0.605) g : (1.012-1.042) g : (15-20) mL : (0.562-0.604) g : (0.312-0.357) g.

6. The method for preparing stress corrosion resistant material based on oil slurry steam generator tube sheet according to claim 1, characterized in that, In S2, the ratio of 5-trifluoromethylindole, N,N-dimethylformamide, sodium hydride, and epichlorohydrin is (0.261-0.311) g : (10-18) mL : (0.09-0.13) g : (0.608-0.647) g; in S3, the ratio of product c, N,N-dimethylformamide, potassium carbonate, and product b is (0.388-0.446) g : (18-22) mL : (0.688-0.742) g : (0.688-0.748) g.

7. The method for preparing stress corrosion resistant material based on oil slurry steam generator tube sheet according to claim 1, characterized in that, In step one, the ratio of water-based polytetrafluoroethylene resin dispersion, deionized water, composite high-temperature stabilizer, stress corrosion inhibitor, surfactant and coupling agent is (70-85) g: (20-40) mL: (10-15) g: (8-14) g: (2.4-4.3) g: (1.1-1.5) g.

8. A stress corrosion resistant material based on the tube sheet of an oil slurry steam generator, characterized in that, It is prepared by the preparation method according to any one of claims 1-7.

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