Oxygen ether-based xanthate metal corrosion inhibitor and preparation method and application thereof

Abstract

The application belongs to the field of metal corrosion prevention, and particularly relates to a novel use of an oxygen ether group xanthate compound as a metal corrosion inhibitor. The compound described in the application can produce a synergistic effect based on the action of an oxygen ether group and a xanthate group, has good corrosion inhibition performance on carbon steel in an acid pickling solution, and has the advantages of simple preparation method, small use amount and suitability for large-scale production. Meanwhile, the oxygen ether group xanthate is simple to use, can be added into a hydrochloric acid solution to serve as a cleaning solution for pickling carbon steel, can effectively inhibit the corrosion of carbon steel in an acid solution, and has a high carbon steel release rate.

Description

Technical Field

[0001] This invention relates to a corrosion inhibitor, and more particularly to an oxyether-based xanthate metal corrosion inhibitor for pickling carbon steel, its preparation method and application, belonging to the field of metal corrosion protection technology. Background Technology

[0002] Steel is an essential material for national construction, with wide applications and numerous varieties. However, metal corrosion is a major threat limiting its long-term use, hence the common use of acidic solutions to clean metal surfaces. Hydrochloric acid, due to its slow dissolution rate of base metals such as steel, is often used as an industrial cleaning agent in pickling processes, petrochemical production, and oil well operations (Wang Tiantian. The Influence of Corrosion Inhibitors on Metal Corrosion Behavior in Hydrochloric Acid Media [D]. Northwest University. 2018; Ren Tiegang, Su Huishuang, Liu Yue, et al. Research Progress on Metal Corrosion Inhibitors [J]. Chemical Research, 2018, 29, 331-342). However, its volatility and environmental pollution can cause surface rusting, cracking, and localized pitting and perforation of metals in hydrochloric acid solutions. Corrosion not only affects industrial production efficiency, but its products and engineering waste also threaten human health and life to some extent. Therefore, adopting appropriate technologies to control or slow down metal corrosion in hydrochloric acid solutions is a key issue that needs to be addressed.

[0003] Among current metal corrosion prevention measures, the use of organic corrosion inhibitors containing heteroatoms such as N, O, S, and P, as well as aromatic rings, is a simple and cost-effective approach (Wang Juan, Chen Kefeng, Liu Shuan, et al. An imidazole polyaromatic amine metal corrosion inhibitor and its preparation method and application. Chinese Invention Patent, CN108018561A; Li Shouting. Study on corrosion inhibition mechanism and adsorption characteristics of sulfonamide corrosion inhibitors on metal surfaces [D]. Shanghai Normal University. 2022; Zhu Liqin, Liu Ruiquan, Wang Jide. Corrosion inhibition effect of thiadiazole derivatives on Cu in 3% NaHCO3 solution [J]. Chinese Journal of Corrosion and Protection. 2006, 26, 125-128). Xanthate esters are a class of compounds possessing both C=S groups. Studies have shown that these compounds can exhibit strong chelation effects with metal ions by donating the lone pair electrons of the C=S groups. They are currently widely used in mineral flotation, lubricant additives, etc. (Zhong Hong, Huang Xiaoping, Wang Shuai, et al. An O-alkyl-S-hydroxyalkyl xanthate ester collector and its preparation and application. Chinese Invention Patent, CN 108722677B; Wang Yonggang, Mu Xiaoming, Wang Yong. A borate ester derivative containing xanthic acid groups and its preparation method and uses. Chinese Invention Patent, CN104761579A). However, reports on the application of xanthate esters in metal corrosion inhibition are currently scarce. Summary of the Invention

[0004] The purpose of this invention is to provide a novel application of oxyether xanthate compounds in metal corrosion protection.

[0005] To achieve the technical objective of this invention, the technical solution of this invention is implemented in the following manner.

[0006] Uses of an oxyether xanthate compound: as a metal corrosion inhibitor for metal corrosion protection.

[0007] The oxyether xanthate compounds described herein have the structure shown in Formula I:

[0008]

[0009] In formula I, R 1 C1~C 16 alkyl or alkoxyalkyl, R 2 It is a C1 to C6 alkylene group, R 3 For C2~C 16 olefinic group, C5-C 16 Cyclic groups or C6~C 16 aryl or alkylaryl, C2-C 10 alkyl acyl group.

[0010] The alkyl, olefinic, cycloalkyl, aryl, or alkylaryl groups are permitted to have substituents; the substituents are at least one of C1-C6 alkyl, C1-C6 alkoxy, C1-C6 alkylthio, or hydroxyl groups.

[0011] As a preferred option, R 1 It is selected from methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, pentyl, isopentyl, sec-pentyl, neopentyl, n-hexyl, isohexyl, sec-hexyl, n-heptyl, isoheptyl, n-octyl, isooctyl, n-nonyl, undecyl, pentadecyl, or alkoxyalkyl as shown in Formula VI.

[0012] R 4 -OR 5 -

[0013] Style VI

[0014] In equation VI, R 4 C1~C 16 alkyl or alkylaryl, R 5 It is a C1 to C6 alkylene group.

[0015] As a preferred option, R 4 Selected from methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, pentyl, isopentyl, n-hexyl, isohexyl, sec-hexyl, n-heptyl, isoheptyl, and n-octyl.

[0016] Further optimization, R 4 The derivatives are methyl, ethyl, n-butyl, n-hexyl, and n-octyl.

[0017] As a preferred option, R 2 It is selected from methylene, 1,2-ethylene, 1,3-propylene, 1,4-butylene, or 1,5-pentylene.

[0018] R 3 It is ethyl, tert-butyl, benzyl, n-octyl, n-decyl, benzoyl, or octyl.

[0019] The oxyether xanthate compounds of the present invention can be prepared by the synthesis methods described in formulas (1) and (2).

[0020] The preparation steps of the oxyether xanthate of the present invention are as follows:

[0021] Xanthate of formula IV is obtained by xanthation with an alcohol of formula II, carbon disulfide and a monobasic base of formula III; then xanthate of formula IV is esterified with an alkyl halide of formula V to prepare the corresponding oxyether xanthate. The specific synthetic equations are shown in formula (1) and formula (2).

[0022]

[0023] In Equation III, M is Na + K + or NH4 + ;

[0024] In formula V, X is Cl, Br, or I.

[0025] Preferably, during the xanthation reaction, the molar ratio of the alcohol of formula II, carbon disulfide, and monobasic base of formula III is 1:1.0 to 10:1.0 to 1.5.

[0026] The reaction temperature is 10–40℃, and the reaction time is 1–6 h;

[0027] The reaction solvent is one of carbon disulfide or dichloromethane.

[0028] Preferably, the amount of solvent to alcohol is 1 to 5.

[0029] As a preferred embodiment, the esterification reaction conditions for xanthic acid are as follows: the molar ratio of xanthate of formula IV to alkyl halide or alkanoyl halide of formula V is 1:1.0-1.5; the reaction temperature is 10-80℃; and the reaction time is 3-8h.

[0030] The reaction solvent is one of water, dichloromethane, ethyl acetate, acetone, etc.

[0031] Preferably, the amount of solvent used is 10-100 ml solvent / 0.1 mol acyl halide or alkyl acyl halide.

[0032] The present invention also provides, for the first time, the application of the oxyether xanthate compound (compound of formula I) or the oxyether xanthate compound (compound of formula I) prepared by the above preparation method, using it as a metal corrosion inhibitor for the protection of metal materials.

[0033] The present invention also provides a method for pickling metal materials, comprising: cleaning the metal materials with a pickling solution of an acylthiourea corrosion inhibitor prepared by the above method and a mixture of polyethylene glycol.

[0034] Preferably, the pickling solution includes hydrochloric acid, but is not limited thereto.

[0035] Preferably, the metal material includes carbon steel, but is not limited thereto.

[0036] Beneficial effects of the present invention

[0037] This invention is the first to discover that oxyether-based xanthate compounds, when added to acidic cleaning agents as corrosion inhibitors for metallic materials, exhibit good corrosion inhibition performance for carbon steel in pickling solutions.

[0038] In this invention, the corrosion inhibitor of formula I benefits from the electron-donating effect of the C=S group in the molecule, enabling it to interact with metal ions and thus be loaded onto the surface of the metal material. Furthermore, it is combined with the hydrophobic chain R... 1 R 2 and R 3 The combined control helps to form a hydrophobic film on the surface of metal materials, thus achieving a corrosion inhibition effect.

[0039] The present invention also found that, since the oxygen ether group (COC) in the molecule can form hydrogen bonds with water molecules, it enhances the solubility of the molecule in water, which helps the molecule to dissolve and disperse better in acidic cleaning solutions, and can significantly improve the corrosion inhibition performance of metal materials such as carbon steel.

[0040] The present invention also provides a one-pot synthesis method for the corrosion inhibitor, which is simple to operate and has good reaction effect. Attached Figure Description

[0041] [Figure 1] is the 1H NMR spectrum of S-benzyl-O-butoxyethyl xanthate;

[0042] [Figure 2] is the carbon NMR spectrum of S-benzyl-O-butoxyethyl xanthate;

[0043] [Figure 3] is the 1H NMR spectrum of S-benzyl-O-(2-ethoxyethoxy)ethyl xanthate;

[0044] [Figure 4] is the carbon NMR spectrum of S-benzyl-O-(2-ethoxyethoxy)ethyl xanthate; Detailed Implementation

[0045] The present invention is further illustrated by the following embodiments, but is not limited to these embodiments. Unless otherwise specified, all parts and percentages in the embodiments refer to mass.

[0046] Example 1: Preparation of S-benzyl-O-butoxyethyl xanthate

[0047] 5.97 parts of 99% pure ethylene glycol butyl ether, 19.23 parts of 99% pure carbon disulfide, and 2.13 parts of 98.5% pure sodium hydroxide were added to a 100 mL three-necked flask, stirred, and heated to 25 °C for 3.5 hours. After the reaction was complete, 20 mL of distilled water was added to the flask, and after the solid was completely dissolved, 6.39 parts of 99% pure benzyl chloride were added to the reaction vessel, and the temperature was raised to 50 °C for 5 hours. After the reaction was complete, the mixture was filtered to remove salt, and carbon disulfide was recovered by rotary evaporation to obtain the crude product with a purity of 81.26% and a yield of 90.35% based on benzyl chloride. The crude S-benzyl-O-(2-ethoxyethoxy)ethyl xanthate was purified and then subjected to structural characterization. 1 H NMR and 13 The C NMR spectra are shown in Figure 1 and Figure 2, respectively. 1 HNMR and 13 The results of the C1NMR analysis are shown in Table 1.

[0048] Example 2: Preparation of S-benzyl-O-(2-ethoxyethoxy)ethyl xanthate

[0049] 6.78 parts of 99% pure ethoxydiethylene glycol, 19.23 parts of 99% pure carbon disulfide, and 2.13 parts of 98.5% pure sodium hydroxide were added to a 100 mL three-necked flask, stirred, and heated to 25 °C for 3.5 hours. After the reaction was complete, 20 mL of distilled water was added to the flask, and after the solid was completely dissolved, 6.39 parts of 99% pure benzyl chloride were added to the reaction vessel, and the temperature was raised to 50 °C for 5 hours. After the reaction was complete, the mixture was filtered to remove salt, and carbon disulfide was recovered by rotary evaporation to obtain the crude product with a purity of 78.98% and a yield of 88.29% based on benzyl chloride. The crude S-benzyl-O-(2-ethoxyethoxy)ethyl xanthate was purified and then subjected to structural characterization. 1 H NMR and 13 The C NMR spectra are shown in Figures 3 and 4, respectively. 1 H NMR and 13 The results of the C1NMR analysis are shown in Table 1.

[0050] Example 3: Preparation of S-benzyl-O-n-hexyl xanthate

[0051] 5.16 parts of 99% pure n-butanol, 19.23 parts of 99% pure carbon disulfide, and 2.13 parts of 98.5% pure sodium hydroxide were added to a 100 mL three-necked flask, stirred, and heated to 25°C for 3.5 hours. After the reaction was complete, 20 mL of distilled water was added to the flask, and after the solid was completely dissolved, 6.39 parts of 99% pure benzyl chloride were added to the reaction vessel, and the temperature was raised to 50°C for 5 hours. After the reaction was complete, the mixture was filtered to remove salt, and carbon disulfide was recovered by rotary evaporation to obtain the crude product with a purity of 80.02% and a yield of 87.36% based on benzyl chloride.

[0052] Example 4: Preparation of S-benzoyl-O-butoxyethyl xanthate

[0053] 5.97 parts of 99% pure ethylene glycol butyl ether, 19.23 parts of 99% pure carbon disulfide, and 2.13 parts of 98.5% pure sodium hydroxide were added to a 100 mL three-necked flask, stirred, and heated to 25°C for 3.5 hours. After the reaction was complete, 7.10 parts of 99% pure benzoyl chloride were added to the reaction vessel, and the temperature was raised to 50°C for 5 hours. After the reaction was complete, the mixture was filtered to remove salt, and carbon disulfide was recovered by rotary evaporation to obtain the crude product with a purity of 82.36% and a yield of 85.28% based on benzoyl chloride.

[0054] Table 1 shows some of the target products. 1 H NMR and 13 C NMR analysis

[0055]

[0056]

[0057] Example 5: Corrosion inhibition performance of S-benzyl-O-(2-ethoxyethoxy)ethyl xanthate on carbon steel Q235

[0058] Referring to the People's Republic of China Petroleum and Natural Gas Industry Standard "Performance Evaluation Method for Corrosion Inhibitors for Oilfield Produced Water" (SY / T 5273-2014), a standard Q235 carbon steel test piece with dimensions of 50mm × 10mm × 3mm was selected. The surface was polished with metallographic sandpaper until smooth and flat. Surface grease was removed with petroleum ether and anhydrous ethanol, and the sample was washed with deionized water, dried, and weighed for later use. The Q235 carbon steel test piece was immersed in a 1M HCl hydrochloric acid cleaning solution at 25℃ for 72 hours. The cleaning solution contained 0.1M S-benzyl-O-(2-ethoxyethoxy)ethyl xanthate. After the test, the carbon steel was removed, rinsed with distilled water, and then repeatedly washed with petroleum ether and anhydrous ethanol. After drying, it was weighed, and the metal corrosion inhibition rate was calculated using the weight loss of the test piece. The results showed that the corrosion inhibition efficiency of the carbon steel immersed in this cleaning solution was 98.63%.

[0059] Comparative Example 1: Corrosion Inhibition Performance of S-Benzyl-O-Butoxyethyl Xanthate on Carbon Steel Q235

[0060] Referring to the People's Republic of China Petroleum and Natural Gas Industry Standard "Performance Evaluation Method for Corrosion Inhibitors for Oilfield Produced Water" (SY / T 5273-2014), a standard Q235 carbon steel test piece with dimensions of 50mm × 10mm × 3mm was selected. The surface was polished with metallographic sandpaper until smooth and flat. Surface grease was removed with petroleum ether and anhydrous ethanol, respectively. After washing with deionized water, the sample was dried and weighed for later use. The Q235 carbon steel standard test piece was immersed in a 1M HCl hydrochloric acid cleaning solution at 25℃ for 72 hours. The cleaning solution contained 0.1M S-benzyl-O-butoxyethyl xanthate. After the test, the carbon steel was removed, rinsed with distilled water, and then repeatedly cleaned with petroleum ether and anhydrous ethanol. After drying, it was weighed, and the metal corrosion inhibition rate was calculated using the weight loss of the test piece. The results showed that the corrosion inhibition efficiency of the carbon steel immersed in this cleaning solution was 87.33%.

[0061] Comparative Example 2: Corrosion Inhibition Performance of S-Benzyl-O-n-Hexyl Xanthate on Carbon Steel Q235

[0062] Referring to the People's Republic of China Petroleum and Natural Gas Industry Standard "Performance Evaluation Method for Corrosion Inhibitors for Oilfield Produced Water" (SY / T 5273-2014), a standard Q235 carbon steel test piece with dimensions of 50mm × 10mm × 3mm was selected. The surface was polished with metallographic sandpaper until smooth and flat. Surface grease was removed with petroleum ether and anhydrous ethanol, respectively. After washing with deionized water, the sample was dried and weighed for later use. The Q235 carbon steel standard test piece was immersed in a 1M HCl hydrochloric acid cleaning solution at 25℃ for 72 hours. The cleaning solution contained 0.1M S-benzyl-O-n-hexyl xanthate. After the test, the carbon steel was removed, rinsed with distilled water, and then repeatedly cleaned with petroleum ether and anhydrous ethanol. After drying, it was weighed, and the metal corrosion inhibition rate was calculated using the weight loss of the test piece. The results showed that the corrosion inhibition efficiency of the carbon steel immersed in this cleaning solution was 55.36%.

[0063] Example 6: Corrosion Inhibition Performance of S-benzoyl-O-butoxyethyl xanthate on Carbon Steel Q235

[0064] Referring to the People's Republic of China Petroleum and Natural Gas Industry Standard "Performance Evaluation Method for Corrosion Inhibitors for Oilfield Produced Water" (SY / T 5273-2014), a standard Q235 carbon steel test piece with dimensions of 50mm × 10mm × 3mm was selected. The surface was polished with metallographic sandpaper until smooth and flat. Surface grease was removed with petroleum ether and anhydrous ethanol, respectively. After washing with deionized water, the sample was dried and weighed for later use. The Q235 carbon steel standard test piece was immersed in a 1M HCl hydrochloric acid cleaning solution at 25℃ for 72 hours. The cleaning solution contained 0.1M S-benzoyl-O-butoxyethyl xanthate. After the test, the carbon steel was removed, rinsed with distilled water, and then repeatedly cleaned with petroleum ether and anhydrous ethanol. After drying, it was weighed, and the metal corrosion inhibition rate was calculated using the weight loss of the test piece. The results showed that the corrosion inhibition efficiency of the carbon steel immersed in this cleaning solution was 95.66%.

[0065] This invention synthesizes oxyether-based xanthate compounds from alcohols, monobasic bases, carbon disulfide, and alkyl halides. The synthesis method is simple and yields good results. This invention innovatively applies oxyether-based xanthate compounds to corrosion inhibitors for carbon steel materials. It was found that, with the same carbon chain length, increasing the number of oxyether groups improves the solubility of the molecule in hydrochloric acid solution and enhances its corrosion inhibition effect on metals. Furthermore, introducing a carbonyl group at the ortho position of the xanthate group enhances the molecule's slow-release performance on metal materials through synergistic chelation between the groups. The oxyether-based xanthates prepared by this invention can be mixed into hydrochloric acid solution, significantly increasing the corrosion inhibition performance of carbon steel materials during pickling, and have broad practical application prospects.

Claims

1. Use of an oxylether xanthate compound as a metal corrosion inhibitor, characterized in that, It is used as an inhibitor for carbon steel in pickling cleaning solution; The oxyether xanthate compound has the structure shown in formula I: Formula I In formula I, R 1 is a C1-C 16 alkyl or alkoxyalkyl group, R 2 is a C1-C6 alkylene group, R 3 is a C2-C 16 alkenyl group, a C5-C 16 cycloalkyl group, a C2-C 10 alkanoyl group, a C6-C 16 aryl group, or a C6-C 16 alkylaryl group.

2. Use according to claim 1, characterized in that, The alkyl, alkene, cyclic, aryl or alkyl aryl group has a substituent; the substituent is at least one of C1-C6 alkyl, C1-C6 alkoxy, C1-C6 alkylthio, hydroxyl.

3. Use according to claim 2, characterized in that, The alcohol with formula II, carbon disulfide and monobasic base with formula III are reacted to prepare xanthate with formula IV; the xanthate with formula IV is reacted with alkyl halide with formula V to prepare oxyether xanthate with formula I; the specific synthesis equation is as follows: ； ； Formula VI In formula II, R 1 is a C1-C 16 alkyl group or an alkoxyalkyl group of formula VI; In formula III, M is Na + , K + , or NH4 + ; In formula V, X is Cl, Br or I; In formula VI, R 4 is a C1-C 16 alkyl group or a C1-C 16 alkyl aryl group, and R 5 is a C1-C6 alkylene group.

4. Use according to claim 3, characterized in that, R 1 selected from ethyl, propyl, butyl, pentyl, heptyl, octyl, nonyl, undecyl, pentadecyl, ethoxyethyl, butoxyethyl, t-butoxyethyl; The R 2 alkylene in said R1is methylene, 1,2-ethylidene, 1,3-propylidene, 1,4-butylidene or 1,5-pentylidene.

5. Use according to claim 4, characterized in that, When the alcohol with formula II, carbon disulfide and monobasic base with formula III are reacted, the molar ratio is 1:1.0-10:1.0-1.5, the reaction temperature is 10-40℃, the reaction time is 1-6h, and the molar amount of the alcohol with formula II: the molar amount of carbon disulfide =1-5; When the xanthate with formula IV is reacted with alkyl halide with formula V, the molar ratio is 1:1.0-1.5, the reaction temperature is 10-80℃, and the reaction time is 3-8h.

6. Use according to claim 5, characterized in that, The use includes adding the oxyether xanthate in the environment where the metal material is located, and making the oxyether xanthate in contact with the metal material; The environment is a liquid phase or gas phase environment which is corrosive to the metal material.

7. Use according to claim 6, characterized in that, The use includes adding the oxyether xanthate compound with formula I in the pickling solution before pickling the metal material or during the pickling process of the metal material; the metal material includes carbon steel.

8. A pickling method of a metal material, characterized by, The application is applied to the pickling process included in the use of claim 7, and the metal material is cleaned by the pickling solution containing the metal inhibitor of the oxyether xanthate with formula I, and the pickling solution includes hydrochloric acid and sulfuric acid.

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