A high temperature resistant corrosion inhibitor and its application in lubricating oil

Abstract

The present invention discloses a high temperature resistant corrosion inhibitor and its application in lubricating oil. The high temperature resistant corrosion inhibitor comprises the following material compositions by mass: 0-20 parts of organic phosphate, 5-10 parts of alkyl urea, 6-14 parts of sorbitol monooleate, and 0-10 parts of petroleum calcium sulfonate. The preparation method of the high temperature resistant corrosion inhibitor comprises the following steps: S1, evenly mixing organic phosphate and alkyl urea; S2, adding sorbitol monooleate and petroleum calcium sulfonate to the mixture obtained in step S1, heating to 80-100°C, and evenly mixing; S3, passing dry nitrogen into the mixed solution obtained in step S2 to take away oxygen and moisture in the mixed solution; S4, vacuuming the mixture obtained in step S4 for a second time to remove moisture, and obtaining a high temperature resistant corrosion inhibitor. After the prepared anti-corrosion inhibitor is added to lubricating oil, it can be used in aircraft engines and automobile engines.

Description

Technical Field

[0001] The invention relates to a corrosion inhibitor, in particular to a high temperature resistant corrosion inhibitor and application thereof in lubricating oil. Background Art

[0002] High temperature lubricant inhibitors usually refer to special chemical additives added to lubricants used in high temperature environments to enhance the performance of lubricants and ensure effective lubrication, oxidation stability and other protective properties under high temperature conditions. There are mainly the following types:

[0003] 1. High temperature antioxidant: It can effectively inhibit the oxidation reaction of lubricating oil at high temperature, slow down the deterioration process of oil products, and extend the service life of lubricating oil. It is suitable for high-performance gasoline and diesel engine oils, etc.

[0004] 2. Anti-wear agents: Anti-wear agents can form boundary lubrication films, reduce direct contact between metals, and protect equipment from wear. At high temperatures, the viscosity of the lubricating oil may decrease, causing the lubricating film to become thinner and increasing the risk of wear.

[0005] 3. Rust and corrosion inhibitors: In high-temperature operating environments, lubricants must also prevent metal parts of the equipment from rusting and corroding. These additives can form a protective layer on the metal surface to isolate moisture and corrosive media.

[0006] CN110951520B provides a rust inhibitor for gasoline vehicle initial filling oil and its preparation method. The present invention combines antioxidants, corrosion inhibitors, rust inhibitors, dispersants, and solvent oil in a certain proportion, and the corrosion inhibitor is selected from one or more of DT-207, XGC-7C and oil-soluble imidazoline; the rust inhibitor is selected from one or more of benzotriazole, methylbenzothiazole and T746. The above-mentioned specific components work synergistically to form a protective film at the contact surface between the engine and the fuel, which can effectively slow down the seawater corrosion of the engine, improve the high temperature oxidation resistance and stability of the fuel, and meet the performance indicators of the initial filling oil of the automobile oil, but the performance of the use performance still has a lot of room for improvement. Summary of the invention

[0007] The purpose of the present invention is to provide a high temperature resistant corrosion inhibitor and its application in lubricating oil.

[0008] To achieve the above object, the high temperature resistant corrosion inhibitor adopted by the present invention comprises the following material compositions by weight:

[0009] Organic phosphate 0~20 parts

[0010] Alkyl urea 5~10 parts

[0011] 6-14 parts of sorbitan monooleate

[0012] Calcium petroleum sulfonate 0-10 parts.

[0013] Alkyl urea has a high boiling point (above 200°C), strong antioxidant properties, and high temperature resistance. It also contains nitrogen atoms. The lone pair of electrons on the nitrogen atom can form a coordination bond with the empty orbit of the metal and has a strong binding ability with the metal, thereby forming an adsorption film on the metal surface to reduce the erosion of the corrosive medium on the metal. In addition, the nitrogen atoms can combine with the hydrogen ions generated by corrosion to reduce the corrosion of the metal. Therefore, adding the alkyl urea component has a good anti-corrosion effect and is resistant to high temperatures.

[0014] Furthermore, the organic phosphate is a salt formed by di(2-ethylhexyl)phosphate and amine.

[0015] Furthermore, the amine is urotropine or dodecylamine. The organic phosphate used in the present invention, especially the salt synthesized from urotropine, has a cyclic structure and isomeric, which enhances the compatibility with lubricating oil. In addition to the nitrogen atoms that form the salt, other nitrogen atoms can neutralize hydrogen ions, which is a better choice.

[0016] Furthermore, the synthesis method of the organic phosphate is to mix di(2-ethylhexyl) phosphate and amine evenly, heat to 150-200° C. for reaction for 3-5 hours, and perform reduced pressure distillation to remove impurities to obtain the organic phosphate.

[0017] Furthermore, the molar ratio of the di(2-ethylhexyl) phosphate to the amine is 1:1. The formula of the two materials must be strictly controlled so that the prepared organic phosphate can meet the requirements of the preservative, and the molar number of the amine cannot be less than the molar number of the di(2-ethylhexyl) phosphate.

[0018] Furthermore, the heating method is microwave heating, which has high yield and fast reaction.

[0019] Furthermore, the alkyl urea is tetrabutyl urea or tetraethyl urea.

[0020] At the same time, the present invention also provides a method for preparing the above-mentioned high temperature resistant corrosion inhibitor, comprising the following steps:

[0021] S1. Mix the organic phosphate and alkyl urea uniformly;

[0022] S2: adding sorbitan monooleate and calcium petroleum sulfonate to the mixture obtained in step S1, heating the mixture to 80-100° C., and mixing the mixture uniformly;

[0023] S3. Passing dry nitrogen into the mixed solution obtained in step S2 to remove oxygen and moisture in the mixed solution;

[0024] S4: The mixture obtained in step S4 is vacuumed for a second time to remove moisture to obtain a high temperature resistant corrosion inhibitor. Moisture can easily cause corrosion of metals. In lubricating oil, moisture, metals and oxygen are the basic elements of electrochemical reactions. Corrosion will produce unevenly distributed pitting on the metal surface, causing great damage to the structure of mechanical equipment. Therefore, it is necessary to add an appropriate amount of corrosion inhibitor to the lubricating oil. The corrosion inhibitor prepared by the present invention removes moisture and oxygen through multiple pathways, and the content of water and oxygen is extremely low, so the use effect is better.

[0025] In addition, the invention also provides the use of the above-mentioned high temperature resistant corrosion inhibitor in lubricating oil, which can be applied to aircraft engines and automobile engines.

[0026] Compared with the prior art, the technical solution of the present invention has at least the following advantages:

[0027] 1. The preparation method is simple and easy for industrial production.

[0028] 2. The anti-corrosion effect is good, the solvent used is resistant to high temperature and suitable for high temperature environment.

[0029] 3. Widely used, can be applied to automobile engines, aviation engines and other fields. DETAILED DESCRIPTION

[0030] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0032] Example 1

[0033] A high temperature resistant corrosion inhibitor, comprising the following material compositions by mass:

[0034] Organic phosphate 5kg

[0035] Tetrabutylurea 6kg

[0036] Sorbitol monooleate 8kg

[0037] Calcium petroleum sulfonate 3kg.

[0038] The organic phosphate is a salt formed by di(2-ethylhexyl)phosphate and dodecylamine.

[0039] The synthesis method of the organic phosphate is as follows: di(2-ethylhexyl)phosphate and dodecylamine are uniformly mixed, heated in an oil bath to 150-170°C for reaction for 5 hours, and distilled under reduced pressure to remove impurities to obtain the organic phosphate. The molar ratio of the di(2-ethylhexyl)phosphate and dodecylamine is 1:1, the amount of dodecylamine added is 18.5kg, and the amount of di(2-ethylhexyl)phosphate added is 32.2kg. Only part of the synthesized organic phosphate is used in the above formula.

[0040] The method for preparing the high temperature resistant corrosion inhibitor comprises the following steps:

[0041] S1. Mix the organic phosphate and alkyl urea uniformly;

[0042] S2: adding sorbitol monooleate and calcium petroleum sulfonate to the mixture obtained in step S1, heating the mixture to 80-90° C., and mixing the mixture evenly;

[0043] S3. Passing dry nitrogen into the mixed solution obtained in step S2 to remove oxygen and moisture in the mixed solution;

[0044] S4: The mixture obtained in step S4 is subjected to vacuum treatment to remove moisture for a second time to obtain a high temperature resistant corrosion inhibitor.

[0045] The prepared high-temperature corrosion inhibitor can be used in automobile engines and aviation engines.

[0046] Example 2

[0047] A high temperature resistant corrosion inhibitor, comprising the following material compositions by mass:

[0048] Organic phosphate 15kg

[0049] Tetraethyl urea 8kg

[0050] Sorbitol monooleate 10kg

[0051] Calcium petroleum sulfonate 8kg.

[0052] The organic phosphate is a salt formed by di(2-ethylhexyl)phosphate and urotropine.

[0053] The synthesis method of the organic phosphate comprises the following steps: uniformly mixing di(2-ethylhexyl) phosphate and urotropine, heating the mixture to a temperature between 150° C. and 170° C. by microwave to react for 3 hours, and performing reduced pressure distillation to remove impurities to obtain the organic phosphate. The molar ratio of the di(2-ethylhexyl) phosphate to the urotropine is 1:1, the amount of urotropine added is 14.0 kg, the amount of di(2-ethylhexyl) phosphate added is 32.2 kg, and only a part of the synthesized organic phosphate is used in the above formula.

[0054] The method for preparing the high temperature resistant corrosion inhibitor comprises the following steps:

[0055] S1. Mix the organic phosphate and alkyl urea uniformly;

[0056] S2: adding sorbitan monooleate and calcium petroleum sulfonate to the mixture obtained in step S1, heating the mixture to 90-100° C., and mixing the mixture uniformly;

[0057] S3. Passing dry nitrogen into the mixed solution obtained in step S2 to remove oxygen and moisture in the mixed solution;

[0058] S4: The mixture obtained in step S4 is subjected to vacuum treatment to remove moisture for a second time to obtain a high temperature resistant corrosion inhibitor.

[0059] The prepared high-temperature corrosion inhibitor can be used in automobile engines and aviation engines.

[0060] Example 3

[0061] A high temperature resistant corrosion inhibitor, comprising the following material compositions by mass:

[0062] Tetraethyl urea 8kg

[0063] Sorbitol monooleate 10kg

[0064] Calcium petroleum sulfonate 8kg.

[0065] The organic phosphate is a salt formed by di(2-ethylhexyl)phosphate and urotropine.

[0066] The synthesis method of the organic phosphate comprises the following steps: uniformly mixing di(2-ethylhexyl) phosphate and urotropine, heating the mixture to a temperature between 150° C. and 170° C. by microwave to react for 3 hours, and performing reduced pressure distillation to remove impurities to obtain the organic phosphate. The molar ratio of the di(2-ethylhexyl) phosphate to the urotropine is 1:1, the amount of urotropine added is 14.0 kg, the amount of di(2-ethylhexyl) phosphate added is 32.2 kg, and only a part of the synthesized organic phosphate is used in the above formula.

[0067] The method for preparing the high temperature resistant corrosion inhibitor comprises the following steps:

[0068] S1. Mix the organic phosphate and alkyl urea uniformly;

[0069] S2: adding sorbitan monooleate and calcium petroleum sulfonate to the mixture obtained in step S1, heating the mixture to 90-100° C., and mixing the mixture uniformly;

[0070] S3. Passing dry nitrogen into the mixed solution obtained in step S2 to remove oxygen and moisture in the mixed solution;

[0071] S4: The mixture obtained in step S4 is subjected to vacuum treatment to remove moisture for a second time to obtain a high temperature resistant corrosion inhibitor.

[0072] The prepared high-temperature corrosion inhibitor can be used in automobile engines and aviation engines.

[0073] Example 4

[0074] A high temperature resistant corrosion inhibitor, comprising the following material compositions by mass:

[0075] Organic phosphate 5kg

[0076] Tetrabutylurea 6kg

[0077] Sorbitol monooleate 8kg.

[0078] The organic phosphate is a salt formed by di(2-ethylhexyl)phosphate and dodecylamine.

[0079] The synthesis method of the organic phosphate is as follows: di(2-ethylhexyl)phosphate and dodecylamine are uniformly mixed, heated in an oil bath to 150-170°C for reaction for 5 hours, and distilled under reduced pressure to remove impurities to obtain the organic phosphate. The molar ratio of the di(2-ethylhexyl)phosphate and dodecylamine is 1:1, the amount of dodecylamine added is 18.5kg, and the amount of di(2-ethylhexyl)phosphate added is 32.2kg. Only part of the synthesized organic phosphate is used in the above formula.

[0080] The method for preparing the high temperature resistant corrosion inhibitor comprises the following steps:

[0081] S1. Mix the organic phosphate and alkyl urea uniformly;

[0082] S2: adding sorbitol monooleate and calcium petroleum sulfonate to the mixture obtained in step S1, heating the mixture to 80-90° C., and mixing the mixture evenly;

[0083] S3. Passing dry nitrogen into the mixed solution obtained in step S2 to remove oxygen and moisture in the mixed solution;

[0084] S4: The mixture obtained in step S4 is subjected to vacuum treatment to remove moisture for a second time to obtain a high temperature resistant corrosion inhibitor.

[0085] The prepared high-temperature corrosion inhibitor can be used in automobile engines and aviation engines.

[0086] Example 5

[0087] A high temperature resistant corrosion inhibitor, comprising the following material compositions by mass:

[0088] Tetrabutylurea 6kg

[0089] Sorbitol monooleate 8kg.

[0090] The organic phosphate is a salt formed by di(2-ethylhexyl)phosphate and dodecylamine.

[0091] The synthesis method of the organic phosphate is as follows: di(2-ethylhexyl)phosphate and dodecylamine are uniformly mixed, heated in an oil bath to 150-170°C for reaction for 5 hours, and distilled under reduced pressure to remove impurities to obtain the organic phosphate. The molar ratio of the di(2-ethylhexyl)phosphate and dodecylamine is 1:1, the amount of dodecylamine added is 18.5kg, and the amount of di(2-ethylhexyl)phosphate added is 32.2kg. Only part of the synthesized organic phosphate is used in the above formula.

[0092] The method for preparing the high temperature resistant corrosion inhibitor comprises the following steps:

[0093] S1. Mix the organic phosphate and alkyl urea uniformly;

[0094] S2: adding sorbitol monooleate and calcium petroleum sulfonate to the mixture obtained in step S1, heating the mixture to 80-90° C., and mixing the mixture evenly;

[0095] S3. Passing dry nitrogen into the mixed solution obtained in step S2 to remove oxygen and moisture in the mixed solution;

[0096] S4: The mixture obtained in step S4 is subjected to vacuum treatment to remove moisture for a second time to obtain a high temperature resistant corrosion inhibitor.

[0097] The prepared high-temperature corrosion inhibitor can be used in automobile engines and aviation engines.

[0098] Comparative Example 1

[0099] The tetrabutyl urea in Example 1 is replaced by tetramethylbenzene, and the rest is the same as Example 1 and will not be described in detail.

[0100] Comparative Example 2

[0101] Step S4 in Example 1 is removed, and the rest is the same as Example 1 and will not be described in detail.

[0102] Performance Testing:

[0103] The high temperature corrosion inhibitors prepared in the above examples and comparative examples were added to lubricating oil, and performance tests were carried out according to SH / T0195-1992. The test results are shown in Table 1.

[0104] Table 1 Performance test results

[0105] Serial number Test Results Corrosion inhibitor addition, % Example 1 qualified 2 Example 2 qualified 2 Example 3 qualified 3 Example 4 qualified 3 Example 5 qualified 5 Comparative Example 1 Failure 5 Comparative Example 2 qualified 7

[0106] It can be seen from the data in the above table that the inhibitors prepared in the examples of the present invention are all qualified when added to lubricating oil, but the addition amount of Examples 3 to 5 needs to be increased due to the lack of synergistic effect between components. The data of Comparative Example 1 shows that alkyl urea is the preferred and better formulation component; the data of Comparative Example 2 shows that the addition amount needs to be further increased to meet the requirements, and long-term use shows that step S4 is an indispensable step that can extend the service life of the lubricating oil.

Claims

1. A high temperature resistant corrosion inhibitor, characterized in that: Includes the following substances in parts by mass: 5~20 parts of organic phosphate Alkyl urea 5~10 parts 6-14 parts of sorbitan monooleate Calcium petroleum sulfonate 3-10 parts; The organic phosphate is a salt formed by di(2-ethylhexyl) phosphate and amine; The amine is hexamethylenetetramine or dodecylamine; The alkyl urea is tetrabutyl urea or tetraethyl urea.

2. The high temperature resistant corrosion inhibitor according to claim 1, characterized in that: The synthesis method of the organic phosphate is to mix di(2-ethylhexyl) phosphate and amine evenly, heat to 150-200° C. for reaction for 3-5 hours, and perform reduced pressure distillation to remove impurities to obtain the organic phosphate.

3. The high temperature resistant corrosion inhibitor according to claim 2, characterized in that: The molar ratio of the di(2-ethylhexyl)phosphate to the amine is 1:

1.

4. The high temperature resistant corrosion inhibitor according to claim 2, characterized in that: The heating method is microwave heating.

5. The method for preparing a high temperature resistant corrosion inhibitor according to any one of claims 1 to 4, characterized in that: The steps include: S1. Mix the organic phosphate and alkyl urea uniformly; S2: adding sorbitan monooleate and calcium petroleum sulfonate to the mixture obtained in step S1, heating the mixture to 80-100° C., and mixing the mixture uniformly; S3. Passing dry nitrogen into the mixed solution obtained in step S2 to remove oxygen and moisture in the mixed solution; S4: The mixture obtained in step S4 is subjected to vacuum treatment to remove moisture for a second time to obtain a high temperature resistant corrosion inhibitor.

6. Use of the high temperature resistant corrosion inhibitor according to any one of claims 1 to 4 in lubricating oil, characterized in that: Used in aircraft engines and automobile engines.