Air compressor lubricating oil with low odor and long service life

Abstract

The invention relates to air compressor lubricating oil with low odor and long service life. The air compressor lubricating oil with low odor and long service life is prepared from the following raw materials in percentage by weight: 0.2 to 1 percent of additive A, 0.5 to 2.0 percent of additive B, 0.03 to 0.1 percent of antirust agent, 0.5 to 1.5 percent of antioxidant, 0.0075 to 0.01 percent of defoaming agent and the balance of second-class hydrofined mineral oil. The additive A and the additive B are compounded to replace a traditional additive, the heat stability, oxidation stability and wear resistance of the air compressor lubricating oil can be remarkably improved within a proper dosage range, and in practical application, the oil change period of the air compressor lubricating oil is remarkably prolonged and can exceed 6000 hours. In addition, through compounding of the additive A and the additive B, the problem that a traditional additive has serious odor after being used for a period of time is solved.

Description

Technical Field

[0001] The invention belongs to the technical field of lubricating oils, and in particular relates to an air compressor lubricating oil with low odor and long service life. Background Art

[0002] Air compressors (hereinafter referred to as "air compressors") are equipment that provide compressed air, a high-quality power source. Due to their advantages such as simple design and control, low operating costs, and strong environmental adaptability, they are widely used in various fields of industry, agriculture, national defense, transportation, and life. Among them, some applications have relatively high requirements for the quality of compressed air, such as the medical and food industries. Under high temperature and high oxygen conditions, a small amount of air compressor lubricating oil will evaporate into the air. At the same time, some components will degrade into small molecular compounds and evaporate under high temperature conditions. Some components will be oxidized to generate new products with unpleasant odors. Especially in places with poor ventilation conditions, the odor problem becomes very important. In addition, the emission of unpleasant odors into the air will also pollute the environment.

[0003] Traditional sulfur and phosphorus-containing extreme pressure anti-wear agents and antioxidants will have a strong odor after being used for a period of time, and benzotriazole metal passivators will also have an unpleasant odor under high temperature conditions. Therefore, it is very urgent to develop low-volatile, thermally stable and antioxidant stable environmentally friendly air compressor oils. Summary of the invention

[0004] The purpose of the present invention is to provide an air compressor lubricant with low odor and long service life to solve the technical problem that traditional extreme pressure anti-wear agents and antioxidants containing sulfur and phosphorus have serious odor after being used for a period of time.

[0005] In order to achieve the above purpose, the technical solution adopted by the present invention is:

[0006] An air compressor lubricant with low odor and long service life, characterized in that it comprises the following raw materials calculated by weight percentage: 0.2-1% of additive A, 0.5-2.0% of additive B, 0.03-0.1% of rust inhibitor, 0.5-1.5% of antioxidant, 0.0075-0.01% of defoamer, and the balance is Class II hydrorefined mineral oil; the structure of the additive A is shown in formula (1), and the structure of the additive B is shown in formula (2);

[0007]

[0008] In formula (1), R is selected from an alkyl group or an aryl group, and in formula (2), R is selected from an alkyl group or an aryl group.

[0009] Furthermore, R in formula (1) is selected from dodecyl, octyl or benzyl, and R in formula (2) is selected from butyl, octyl, isomeric tridecyl, tolyl, xylyl, nonylated phenyl.

[0010] Furthermore, the preparation method of the additive A is as follows: under inert gas conditions, salicylic acid is dissolved in toluene, diphenylphosphine chloride and triethylamine are added dropwise under ice bath conditions, reacted at room temperature for 25-35 minutes, a toluene solution containing the R compound is added dropwise, reacted at 65-75° C. for 2-3 hours, and the additive is obtained after evaporation.

[0011] Furthermore, the molar ratio of the salicylic acid to the diphenylphosphine chloride is 1:0.8-1.2, the molar ratio of the salicylic acid to triethylamine is 1:1.5-2.0, and 2-2.5 mL of toluene is added for every mmol of the salicylic acid; the concentration of the toluene solution containing the R compound is 0.4-0.6 mmol / mL, and 2-3 mL of the toluene solution containing the R compound is added for every mmol of the salicylic acid.

[0012] Furthermore, the inert gas is argon.

[0013] Furthermore, the preparation method of the additive B is as follows: glacial acetic acid and paraformaldehyde are mixed and dry hydrogen chloride gas is introduced, and after stirring at room temperature until the solution is clear, a glacial acetic acid solution of 2,6-di-tert-butylphenol is added dropwise, and the reaction is continued for 45-55 minutes and then an intermediate is obtained by extraction; under the protection of an inert gas, the intermediate is mixed with xylene and a compound containing R, and the reaction is carried out at 70-90° C. until no chlorobutane gas is released, and the additive is obtained after evaporation.

[0014] Furthermore, 25-30 mL of glacial acetic acid is added to each gram of the paraformaldehyde; the concentration of the glacial acetic acid solution of 2,6-di-tert-butylphenol is 1-1.1 g / mL; the volume ratio of the glacial acetic acid to the glacial acetic acid solution of 2,6-di-tert-butylphenol is 5.5-6.5:1; the volume ratio of the glacial acetic acid to the xylene is 3.5-4:1; the mass ratio of the paraformaldehyde to the R-containing compound is 1:5.5-6; and the inert gas is nitrogen.

[0015] Furthermore, the antioxidant is one or more of bis(4-(2,4,4-trimethyl-2-pentyl)phenyl)amine and dioctyldiphenylamine.

[0016] Furthermore, the defoaming agent is a non-silicon defoaming agent.

[0017] Furthermore, the second type of hydrorefined mineral oil is one or more of 150N, 500N, 220N, and 250N.

[0018] Beneficial effects of the present invention:

[0019] The present invention uses additive A and additive B to replace traditional additives, which can significantly improve the thermal stability, oxidation stability and anti-wear and wear-reducing properties of air compressor lubricating oil within a suitable dosage range. In practical applications, the oil change cycle of air compressor lubricating oil is significantly improved, and the oil change cycle can exceed 6000 hours. In addition, the compounding of additive A and additive B also avoids the problem that traditional additives have a serious odor after being used for a period of time.

[0020] Traditional lubricating oils need to be added with various additives such as antioxidants, anti-wear agents, extreme pressure agents, rust inhibitors, etc. to stabilize the performance of the lubricating oil. The additive A of the present invention not only has a metal passivation effect, but also has anti-wear and antioxidant functions, and is a multifunctional additive. The additive B contains both a hindered phenol antioxidant functional group and a phosphonate extreme pressure anti-wear functional group. The synergy of additives A and additive B can avoid adding too many types of additives to the lubricating oil. DETAILED DESCRIPTION

[0021] The present invention will be further described below in conjunction with the embodiments of the present invention.

[0022] The general reaction formula of the synthetic additive A is shown in formula (3), and the general reaction formula of the synthetic additive B is shown in formulas (4) and (5).

[0023]

[0024] Defoamers, rust inhibitors, and triphenyl thiophosphate all come from BASF, and the trade name of the rust inhibitor is Irgacor L12. Tricresyl phosphate comes from Tianjin Lihai Petrochemical.

[0025] Example 1

[0026] The low-odor and long-life air compressor lubricant of Example 1 comprises the following raw materials by mass percentage: 0.44% of additive A, 0.7% of additive B, 0.03% of rust inhibitor, 1.56% of antioxidant, 0.01% of defoamer, and the remainder is Class II hydrorefined mineral oil.

[0027] The structure of additive A is shown in formula (6), and the structure of additive B is shown in formula (7). The rust inhibitor is dodecyl succinic acid half ester, the antioxidant is dioctyl diphenylamine, the defoamer is Synative AC AMH 2, and the viscosity grade of the second-class hydrorefined mineral oil is 46 (CNOOC 250N).

[0028]

[0029] The preparation method of additive A is as follows: argon is filled in a reaction container, 9.6 mmol of salicylic acid is taken and dissolved in 20 mL of toluene, 9.6 mmol of diphenylphosphine chloride and 19.2 mmol of triethylamine are added dropwise under ice bath conditions, and then reacted at room temperature for 30 minutes, and then 24 mL of a toluene solution of 1-azidododecane (12 mmol) is added dropwise, and reacted at 70° C. for 2.5 hours, and the solvent and residual raw materials are removed by rotation to obtain additive A. The preparation method of the toluene solution of 1-azidododecane is to dissolve 12 mmol of 1-azidododecane in 24 mL of toluene.

[0030] The preparation method of additive B is as follows: add 600mL glacial acetic acid and 21g paraformaldehyde to a reaction vessel, introduce dry hydrogen chloride gas, stir at room temperature, and after the solution is clarified, add 100mL of glacial acetic acid solution of 2,6-di-tert-butylphenol (103g) dropwise, and continue to react for 50 minutes. Then extract with 400mL benzene, wash the upper liquid with saturated sodium bicarbonate and sodium bisulfite solution, and then dry with anhydrous magnesium sulfate. After benzene is distilled off under reduced pressure, an intermediate is obtained, which is placed in a three-necked flask, flushed with nitrogen protection, and 160mL of xylene and 125.2g (0.5mol) of tributyl phosphite are added. Heat to 70°C, react under stirring until no chlorobutane gas is released. Then distill off the solvent under reduced pressure to obtain additive B. The glacial acetic acid solution of 2,6-di-tert-butylphenol is obtained by dissolving 103g of 2,6-di-tert-butylphenol in 100mL of glacial acetic acid.

[0031] Example 2

[0032] The air compressor lubricating oil with low odor and long service life of Example 2 includes the following raw materials by mass percentage: additive A 1%, additive B 0.5%, rust inhibitor 0.07%, antioxidant 1%, defoamer 0.0075%, and the balance is Class II hydrorefined mineral oil.

[0033] The structure of additive A is shown in formula (6), and the structure of additive B is shown in formula (7). The rust inhibitor is dodecyl succinic acid half ester, the antioxidant is bis(4-(2,4,4-trimethyl-2-pentyl)phenyl)amine, the defoamer is Synative ACAMH 2, and the viscosity grade of the second-class hydrorefined mineral oil is 46 (CNOOC 250N).

[0034] Example 3

[0035] The air compressor lubricating oil with low odor and long service life of Example 3 includes the following raw materials by mass percentage: additive A 0.2%, additive B 2%, rust inhibitor 0.03%, antioxidant 0.5%, defoamer 0.01%, and the balance is Class II hydrorefined mineral oil.

[0036] The structure of additive A is shown in formula (8), and the structure of additive B is shown in formula (9). The rust inhibitor is dodecyl succinic acid half ester, the antioxidant is bis(4-(2,4,4-trimethyl-2-pentyl)phenyl)amine, the defoamer is Synative ACAMH 2, and the viscosity grade of the second-class hydrorefined mineral oil is 46 (CNOOC 250N).

[0037]

[0038] The preparation method of additive A is as follows: argon is filled in a reaction container, 9.6 mmol of salicylic acid is taken and dissolved in 20 mL of toluene, 9.6 mmol of diphenylphosphine chloride and 19.2 mmol of triethylamine are added dropwise under ice bath conditions, and then reacted at room temperature for 30 minutes, and then 24 mL of a toluene solution of benzyl azide is added dropwise, and reacted at 70° C. for 2.5 hours, and the solvent and residual raw materials are removed by rotation to obtain additive A. The toluene solution of benzyl azide is obtained by dissolving 12 mmol of benzyl azide in 24 mL of toluene.

[0039] The structure of additive B is as follows: add 600mL of glacial acetic acid and 21g of paraformaldehyde to a reaction vessel, introduce dry hydrogen chloride gas, stir at room temperature, and after the solution is clarified, dropwise add 100mL of glacial acetic acid solution of 2,6-di-tert-butylphenol, and continue to react for about 50 minutes. Then extract with 400mL of benzene, wash the upper liquid with saturated sodium bicarbonate and sodium bisulfite solution, and then dry with anhydrous magnesium sulfate. After benzene is distilled off under reduced pressure, an intermediate is obtained, which is placed in a three-necked flask, flushed with nitrogen protection, and 160mL of xylene and 125.2g (0.5mol) of trioctyl phosphite are added. Heat to 70°C, react under stirring until no chlorobutane gas is released. Then distill off the solvent under reduced pressure to obtain additive B.

[0040] Example 4

[0041] The air compressor lubricating oil with low odor and long service life of Example 4 comprises the following raw materials by mass percentage: additive A 0.5%, additive B 1%, rust inhibitor 0.07%, antioxidant 1%, defoamer 0.0075%, and the balance is Class II hydrorefined mineral oil.

[0042] The structure of additive A is shown in formula (8), and the structure of additive B is shown in formula (9). The rust inhibitor is dodecyl succinic acid half ester, the antioxidant is dioctyl diphenylamine, the defoamer is Synative AC AMH 2, and the viscosity grade of the second-class hydrorefined mineral oil is 46 (CNOOC 250N).

[0043] Comparative Example 1

[0044] The air compressor lubricating oil of Comparative Example 1 includes the following raw materials by mass percentage: 0.1% of additive A, 2% of additive B, 0.03% of rust inhibitor, 1.5% of antioxidant, 0.01% of defoamer, and the balance is Class II hydrorefined mineral oil.

[0045] The structure of additive A is shown in formula (8), and the structure of additive B is shown in formula (9). The rust inhibitor is dodecyl succinic acid half ester, the antioxidant is dioctyl diphenylamine, the defoamer is Synative AC AMH 2, and the viscosity grade of the second-class hydrorefined mineral oil is 46 (CNOOC 250N).

[0046] Comparative Example 2

[0047] The air compressor lubricating oil of Comparative Example 2 includes the following raw materials by mass percentage: additive A 1.1%, additive B 0.4%, rust inhibitor 0.07%, antioxidant 1.5%, defoamer 0.0075%, and the balance is Class II hydrorefined mineral oil.

[0048] The structure of additive A is shown in formula (6), and the structure of additive B is shown in formula (7). The rust inhibitor is dodecyl succinic acid half ester, the antioxidant is bis(4-(2,4,4-trimethyl-2-pentyl)phenyl)amine, the defoamer is Synative ACAMH 2, and the viscosity grade of the second-class hydrorefined mineral oil is 46 (CNOOC 250N).

[0049] Comparative Example 3

[0050] The air compressor lubricating oil of Comparative Example 3 includes the following raw materials by mass percentage: 0.05% of benzotriazole derivative, 2.1% of additive B, 0.03% of rust inhibitor, 0.5% of antioxidant, 0.01% of defoaming agent, and the balance is Class II hydrorefined mineral oil.

[0051] The structure of additive B is shown in formula (9). The rust inhibitor is dodecyl succinic acid half ester, the antioxidant is bis(4-(2,4,4-trimethyl-2-pentyl)phenyl)amine, the defoamer is Synative AC AMH 2, and the viscosity grade of the second-class hydrorefined mineral oil is 46 (CNOOC 250N).

[0052] Comparative Example 4

[0053] The air compressor lubricating oil of Comparative Example 4 includes the following raw materials by mass percentage: additive A 0.5%, tricresol phosphate (TCP) 1%, rust inhibitor 0.07%, antioxidant 1%, defoamer 0.0075%, and the balance is Class II hydrorefined mineral oil.

[0054] The structure of additive A is shown in formula (8), the rust inhibitor is dodecyl succinic acid half ester, the antioxidant is dioctyl diphenylamine, the defoamer is Synative AC AMH 2, and the viscosity grade of the second-class hydrorefined mineral oil is 46 (CNOOC 250N).

[0055] Comparative Example 5

[0056] The air compressor lubricating oil of Comparative Example 5 includes the following raw materials by mass percentage: additive A 0.5%, triphenyl thiophosphate (TPPT) 1%, rust inhibitor 0.07%, antioxidant 1%, defoamer 0.0075%, and the balance is Class II hydrorefined mineral oil.

[0057] The structure of additive A is shown in formula (8), the rust inhibitor is dodecyl succinic acid half ester, the antioxidant is dioctyl diphenylamine, the defoamer is Synative AC AMH 2, and the viscosity grade of the second-class hydrorefined mineral oil is 46 (CNOOC 250N).

[0058] Experimental Example 1

[0059] Laboratory oxidation performance testing and friction and wear performance testing

[0060] The existing national standard test methods or industry standard methods are not suitable for evaluating high-quality, long oil change cycle air compressor oils, so it is necessary to improve the standard TOST test method. Connecting the intake pipe to the gas diffuser is conducive to improving the oxidation strength and shortening the test cycle. Test parameters and test conditions: 175℃, 168 hours, air 10L / h, copper and iron coils as catalysts. Take oil samples after oxidation to test viscosity, acid value and n-pentane insolubles. The greater the change in these indicators, such as viscosity, acid value and n-pentane insolubles, the shorter the service life of the air compressor lubricant.

[0061] Friction and wear test

[0062] Based on the Timken friction tester, one end of the oil tank is connected to the above-mentioned oxidation test oil circuit, and the return oil pipeline is temperature-controlled through an oil bath, which is more conducive to simulating the actual working conditions of the compressor. Test parameters and test conditions: oil temperature is controlled to 90°C, load is 200N, friction ring speed is 800r / min, and friction time is 2 hours. After the test, the wear amount of the friction pair and the temperature change of the oil tank are tested. The larger the wear volume, the worse the anti-wear performance of the lubricant oil. The larger the oil temperature rises, the larger the friction coefficient is, and the worse the friction reduction performance of the air compressor lubricant oil is.

[0063] The oxidation performance test and wear performance test results of Examples 1-4 are shown in Table 1, and the oxidation performance test and wear performance test results of Comparative Examples 1-5 are shown in Table 2.

[0064] Table 1 Oxidation performance test and wear performance test results of Examples 1-4

[0065]

[0066] Table 2 Oxidation performance test and wear performance test results of comparative examples 1-5

[0067]

[0068] As can be seen from Table 1, the total acid value and viscosity change values ​​of the air compressor lubricating oils of Examples 1-4 after high-temperature oxidation are both small, indicating that the air compressor lubricating oils of Examples 1-4 have excellent thermal stability and oxidation stability. The friction and wear test results show that the air compressor lubricating oils of Examples 1-4 have good anti-wear and friction reduction properties, indicating that the combination of additive A and additive B can replace traditional additives and can achieve ideal performance effects within a suitable dosage range. As can be seen from Table 2, the air compressor lubricating oils of Comparative Examples 1-5 have obvious pungent odors after high-temperature oxidation, and the viscosity and total acid value change greatly, exceeding the normal use standard of air compressor lubricating oils, and the friction amount and temperature rise are also relatively obvious, indicating that the anti-wear and friction reduction properties are insufficient. It can be seen from Comparative Examples 3, 4 and 5 that the effects of Examples 1-4 of the present application cannot be achieved by replacing additive A with a benzotriazole derivative or replacing additive B with TCP, TPPT. This is because there is no synergistic effect between the benzotriazole derivative and additive B, TCP, TPPT and additive A, while there is a synergistic effect between additives A and additive B of the present application, and only additives A and additive B are needed to allow the lubricant to have the functions of low odor, antioxidant and anti-wear properties.

[0069] The air compressor lubricating oil of Example 1 was applied to the air compressor for actual measurement, and the relevant parameters were: oil pressure 12.5Bar, oil temperature 95°C, air intake humidity 60-75%, and air intake temperature 30-38°C. After the air compressor ran for 6000 hours, the air compressor lubricating oil of Example 1 was tested. The viscosity growth rate was <10%, the total acid value change rate was <0.5mgKOH / g, the n-pentane insoluble matter was <20ppm, and the iron content was <10ppm. All the test indicators of the air compressor lubricating oil of Example 1 were within the limit range specified in the oil change cycle, indicating that the air compressor lubricating oil has a long oil change cycle. The actual application results show that its oil change cycle can exceed 6000 hours.

Claims

1. An air compressor lubricant with low odor and long service life, characterized in that: The following raw materials are included by weight percentage: Additive A 0.2-1%, additive B 0.5-2.0%, rust inhibitor 0.03-0.1%, antioxidant 0.5-1.5%, defoamer 0.0075-0.01%, and the balance is Class II hydrorefined mineral oil; the structure of the additive A is shown in formula (1), and the structure of the additive B is shown in formula (2); In formula (1), R is selected from an alkyl group or an aryl group, and in formula (2), R is selected from an alkyl group or an aryl group.

2. The air compressor lubricant with low odor and long service life according to claim 1, characterized in that In formula (1), R is selected from dodecyl, octyl or benzyl, and in formula (2), R is selected from butyl, octyl, isomeric tridecyl, tolyl, xylyl, nonylated phenyl.

3. The low-odor and long-life air compressor lubricant according to claim 1, characterized in that: The preparation method of the additive A is as follows: under inert gas conditions, salicylic acid is dissolved in toluene, diphenylphosphine chloride and triethylamine are added dropwise under ice bath conditions, reacted at room temperature for 25-35 minutes, a toluene solution containing the R compound is added dropwise, reacted at 65-75° C. for 2-3 hours, and the additive is obtained after evaporation.

4. The low-odor and long-life air compressor lubricant according to claim 3, characterized in that: The molar ratio of the salicylic acid to the diphenylphosphine chloride is 1:0.8-1.2, the molar ratio of the salicylic acid to triethylamine is 1:1.5-2.0, and 2-2.5 mL of toluene is added for every mmol of the salicylic acid; the concentration of the toluene solution containing the R compound is 0.4-0.6 mmol / mL, and 2-3 mL of the toluene solution containing the R compound is added for every mmol of the salicylic acid.

5. The low-odor and long-life air compressor lubricant according to claim 3, characterized in that: The inert gas is argon.

6. The low odor and long service life air compressor lubricant according to claim 1, characterized in that: The preparation method of the additive B is as follows: glacial acetic acid and paraformaldehyde are mixed and dry hydrogen chloride gas is introduced, and after stirring at room temperature until the solution is clear, a glacial acetic acid solution of 2,6-di-tert-butylphenol is added dropwise, and the reaction is continued for 45-55 minutes and then an intermediate is obtained by extraction; under the protection of an inert gas, the intermediate is mixed with xylene and a compound containing R, and the reaction is carried out at 70-90° C. until no chlorobutane gas is released, and the additive is obtained after evaporation.

7. The low-odor and long-life air compressor lubricant according to claim 6, characterized in that: 25-30 mL of glacial acetic acid is added to each gram of the polyformaldehyde; the concentration of the glacial acetic acid solution of 2,6-di-tert-butylphenol is 1-1.1 g / mL; the volume ratio of the glacial acetic acid to the glacial acetic acid solution of 2,6-di-tert-butylphenol is 5.5-6.5:1; the volume ratio of the glacial acetic acid to the xylene is 3.5-4:1; the mass ratio of the polyformaldehyde to the R-containing compound is 1:5.5-6; and the inert gas is nitrogen.

8. The low odor and long service life air compressor lubricant according to claim 1, characterized in that: The antioxidant is one or more of bis(4-(2,4,4-trimethyl-2-pentyl)phenyl)amine and dioctyldiphenylamine.

9. The low odor and long service life air compressor lubricant according to claim 1, characterized in that: The defoamer is a non-silicon defoamer.

10. The low odor and long service life air compressor lubricant according to claim 1, characterized in that The second type of hydrorefined mineral oil is one or more of 150N, 500N, 220N, and 250N.

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