Compressor oil composition as well as preparation method and application thereof

Abstract

The invention relates to the field of lubricating oil, and discloses a compressor oil composition as well as a preparation method and application thereof, the compressor oil composition comprises polyether base oil, an antioxidant and an antirust agent; wherein the polyether base oil is selected from polyoxyethylene ether polyoxypropylene ether base oil; the ethylene oxide content of the polyoxyethylene ether polyoxypropylene ether base oil is greater than 50wt%. The compressor oil disclosed by the invention has excellent lubricating property, viscosity-temperature property, wear resistance and copper corrosion resistance, particularly has excellent copper part corrosion resistance in an acetic acid environment, can provide good lubricating and sealing effects for a cylinder and a filler of an ultrahigh-pressure ethylene compressor for producing EVA (Ethylene Vinyl Acetate), and ensures normal operation of a unit.

Description

Technical Field

[0001] The present invention relates to the field of lubricating oil, and in particular to a compressor oil composition, a preparation method thereof and an application thereof. Background Art

[0002] Ultra-high-pressure ethylene compressors, which operate at exhaust pressures approaching 300 MPa, are key, core units used in the production of high-pressure low-density polyethylene (LDPE) and ethylene-vinyl acetate (EVA) in the petrochemical, chemical, and coal chemical industries. EVA is produced from ethylene and acetic acid, and its downstream products have permeated every aspect of our lives, including footwear, film, wire and cable, toys, hot-melt adhesives, and coatings.

[0003] Ethylene compressor oil, used for lubrication and sealing of cylinders and packings, comes into direct contact with copper components in ultra-high-efficiency ethylene compressor units, such as packing rings and pressure-reducing throttle rings. Acetic acid, the primary raw material for EVA production, is acidic, which can cause corrosion of copper components in ultra-high-efficiency ethylene compressor units. This poses a significant risk and can even lead to unit malfunction. Therefore, the oil must exhibit excellent resistance to metal corrosion, particularly against copper corrosion in acetic acid environments.

[0004] CN114644953A discloses a white oil-based ethylene compressor oil composition and a preparation method thereof. The ethylene compressor oil composition comprises 70-90 parts by weight of a white oil-based base oil, 10-30 parts by weight of a tackifier, 0.05-0.5 parts by weight of a pour point depressant, 0.5-3 parts by weight of an antioxidant, and 0.5-5 parts by weight of a rust inhibitor. The white oil-based base oil is a highly refined mineral white oil with a sulfur content of less than 10 mg / kg. The compressor oil composition disclosed in this method utilizes multiple additives. The resulting engine oil composition exhibits excellent lubricity, thermal and oxidative stability, rust resistance, and a low tendency to carbon deposit.

[0005] CN102311848A discloses an ultra-high-pressure ethylene compressor oil. The oil comprises 93-99 wt% of a polyether synthetic oil, 0.1-2 wt% of an antioxidant, and 0-5 wt% of a rust inhibitor. The polyether base oil is polyalkylene glycol or polyethylene glycol, the antioxidant is one or more of an alkylphenol, an alkylamine, or a sulfur-nitrogen composite antioxidant, and the rust inhibitor is a petroleum sulfonate or a synthetic sulfonate. This method uses the polyether synthetic oil as the base oil and adds specific additives. The resulting composition is capable of resisting dilution of the compressor oil by ethylene gas, preventing accidents such as compressor shutdown and ethylene leakage caused by reduced compressor oil viscosity. Furthermore, the composition exhibits excellent lubricity, thermal and oxidative stability, low carbon deposition tendency, and low biological toxicity.

[0006] In summary, while there are many patents and related articles in China regarding ethylene compressor oils, none mention ethylene compressor oil compositions and methods for their preparation that exhibit resistance to copper corrosion in acetic acid environments. With the development of the EVA resin industry, ethylene compressor oils used in EVA production equipment will require excellent copper corrosion resistance. In particular, ethylene compressor oils that resist copper corrosion in acetic acid environments are crucial for ensuring the stable operation of ultra-high-pressure ethylene compressor units.

[0007] Therefore, there is an urgent need to provide an ethylene compressor oil composition that has excellent copper corrosion resistance in an acetic acid atmosphere. Summary of the Invention

[0008] The purpose of the present invention is to overcome the problem of poor copper corrosion resistance of ethylene compressor oil in an acetic acid environment in the prior art, and to provide a compressor oil composition, a preparation method and an application thereof.

[0009] In order to achieve the above object, the present invention provides a compressor oil composition in a first aspect, wherein the compressor oil composition comprises: a polyether base oil, an antioxidant and a rust inhibitor;

[0010] Wherein, the polyether base oil is selected from polyoxyethylene ether polyoxypropylene ether base oil;

[0011] Wherein, the ethylene oxide content of the polyoxyethylene ether polyoxypropylene ether base oil is greater than 50wt%.

[0012] A second aspect of the present invention provides a method for preparing a compressor oil composition, wherein the method comprises: mixing a polyether base oil, an antioxidant and a rust inhibitor to obtain the compressor oil composition.

[0013] The third aspect of the present invention provides a compressor oil composition prepared by the method of the present invention;

[0014] Preferably, the kinematic viscosity of the compressor oil composition at 40°C is 250-280 mm 2 / s, viscosity index is 230-260.

[0015] A fourth aspect of the present invention provides a use of the compressor oil composition of the present invention in improving the copper corrosion resistance of an ultra-high pressure ethylene compressor in an acetic acid atmosphere.

[0016] Through the above technical solution, the present invention achieves the following beneficial technical effects: the compressor oil described in the present invention has excellent lubricating oil properties, viscosity-temperature properties, anti-wear properties and copper corrosion resistance, especially excellent resistance to copper component corrosion in acetic acid environment, and can provide good lubrication and sealing effects for the cylinder and packing of the ultra-high pressure ethylene compressor for producing EVA, ensuring the normal operation of the unit. DETAILED DESCRIPTION

[0017] The endpoints of the ranges and any values ​​disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered to be specifically disclosed herein.

[0018] A first aspect of the present invention provides a compressor oil composition, wherein the compressor oil composition comprises: a polyether base oil, an antioxidant and a rust inhibitor;

[0019] Wherein, the polyether base oil is selected from polyoxyethylene ether polyoxypropylene ether base oil;

[0020] Wherein, the ethylene oxide content of the polyoxyethylene ether polyoxypropylene ether base oil is greater than 50wt%.

[0021] In the present invention, the polyether base oil has a low peroxide content and is of stable quality under certain storage conditions.

[0022] In the present invention, the ethylene oxide content of the polyoxyethylene ether and polyoxypropylene ether base oil affects the lubricity, viscosity-temperature characteristics, and corrosion resistance of the compressor oil composition. When the ethylene oxide content is less than 50 wt%, the polyether base oil is incompatible with water, resulting in poor water solubility of the polyether base oil, which significantly reduces the viscosity-temperature characteristics (viscosity index) and copper corrosion resistance of the compressor oil composition.

[0023] In the present invention, the ethylene oxide content of the polyoxyethylene ether polyoxypropylene ether base oil is determined by hydrogen nuclear magnetic resonance spectroscopy and carbon nuclear magnetic resonance spectroscopy.

[0024] In the present invention, the polyether base oil can be purchased commercially, for example, polyoxyethylene polyoxypropylene ether base oil can be purchased from Nanjing Well or Zhejiang Huangma Company. The polyether base oil can also be prepared in-house. Taking polyoxyethylene polyoxypropylene ether base oil as an example, the specific preparation method includes: glycerol, propylene oxide, and ethylene oxide are polymerized in the presence of potassium hydroxide at a temperature of 90-95°C and a pressure of 0.4-0.5 MPa.

[0025] In the present invention, preferably, the kinematic viscosity of the polyoxyethylene ether polyoxypropylene ether base oil at 40°C is 260-280m 2 / s.

[0026] According to some embodiments of the present invention, based on the mass of the compressor oil composition, the content of the polyether base oil is 95wt%-99.8wt%, the content of the antioxidant is 0.1wt%-2.5wt%, and the content of the rust inhibitor is 0.1wt%-2.5wt%.

[0027] Preferably, based on the mass of the compressor oil composition, the content of the polyether base oil is 96wt%-99wt%, the content of the antioxidant is 0.9wt%-2.5wt%, and the content of the rust inhibitor is 0.1wt%-1.5wt%.

[0028] According to some embodiments of the present invention, the kinematic viscosity of the compressor oil composition at 40° C. is 250-280 mm 2 / s, viscosity index is 230-260.

[0029] According to some embodiments of the present invention, the antioxidant is selected from amine antioxidants and / or phenolic antioxidants.

[0030] Preferably, the amine antioxidant is selected from alkylamines and / or aromatic amines.

[0031] Preferably, the phenolic antioxidant is selected from alkylene monophenols and / or alkylene bisphenols.

[0032] In the present invention, ethylene compressor oil is susceptible to aging, oxidation and deterioration during use due to the influence of high temperature, high pressure and metal catalyst, generating acidic substances and impurity precipitation, while amine / phenol type antioxidants have a good protective effect against heat, oxygen and ozone, and can also passivate metal ions, with high antioxidant efficiency.

[0033] According to some embodiments of the present invention, the rust inhibitor is selected from benzotriazole and / or benzotriazole derivatives.

[0034] In the present invention, the benzotriazole derivative is at least one selected from toluene benzotriazole, alkyl benzotriazole and naphthyl benzotriazole. Preferably, the benzotriazole derivative is toluene benzotriazole.

[0035] In the present invention, the reactive groups contained in the molecules of the benzotriazole rust inhibitor interact with the metal ions generated during the corrosion process, further polymerize on the metal surface to form a precipitation film, thereby preventing the corrosion process of the copper parts.

[0036] In the present invention, by selecting specific types of polyether base oil, antioxidant and rust inhibitor, and satisfying specific ratios, the components work synergistically to make the compressor oil composition have excellent lubricity, viscosity-temperature properties, anti-wear performance and copper corrosion resistance.

[0037] A second aspect of the present invention provides a method for preparing a compressor oil composition, wherein the method comprises: mixing a polyether base oil, an antioxidant and a rust inhibitor under vacuum conditions to obtain the compressor oil composition.

[0038] In the present invention, the preparation of the compressor oil composition can be carried out in a mixing kettle. The polyether base oil, antioxidant and rust inhibitor can be mixed by first adding the polyether base oil to the mixing kettle, and then adding the antioxidant and rust inhibitor in sequence.

[0039] According to some embodiments of the present invention, the mixing conditions include: a temperature of 100-120° C. and a time of 2-4 h.

[0040] According to some embodiments of the present invention, the vacuum degree of the vacuum condition is -0.97 MPa to -0.92 MPa.

[0041] A third aspect of the present invention provides a compressor oil composition prepared by the method of the present invention.

[0042] Preferably, the compressor oil composition has a kinematic viscosity of 250-280 at 40° C. and a viscosity index of 230-260.

[0043] In the present invention, the kinematic viscosity of the compressor oil composition at 40° C. is measured according to GB / T 265-1988 Petroleum Products Kinematic Viscosity Determination and Dynamic Viscosity Calculation Method; and the viscosity index is measured according to GB / T 1995-1998 Petroleum Products Viscosity Index Counting Method.

[0044] A fourth aspect of the present invention provides a use of the compressor oil composition of the present invention in improving the copper corrosion resistance of an ultra-high pressure ethylene compressor in an acetic acid atmosphere.

[0045] According to a particularly preferred embodiment of the present invention, a method for preparing a compressor oil composition is provided, comprising: adding a polyether base oil, an antioxidant, and a rust inhibitor to a mixing kettle under a vacuum degree of -0.97 MPa to -0.92 MPa, and mechanically stirring the mixture at 100-120° C. for 2-4 hours to obtain an ethylene compressor oil composition;

[0046] Wherein, the ethylene oxide content of the polyoxyethylene ether polyoxypropylene ether base oil is greater than 50wt%;

[0047] Wherein, based on the mass of the compressor oil composition, the content of the polyether base oil is 96wt%-99wt%, the content of the antioxidant is 0.9wt%-2.5wt%, and the content of the rust inhibitor is 0.1wt%-1.5wt%.

[0048] The present invention will be described in detail below through examples.

[0049] The ethylene oxide of the polyoxyethylene ether polyoxypropylene ether base oil in Examples 1-3 was purchased from Nanjing Will or Zhejiang Huangma Company. The ethylene oxide content of the polyoxyethylene ether polyoxypropylene ether base oil was 70 wt %, and the kinematic viscosity at 40° C. was 270 mm 2 / s.

[0050] The polyoxyethylene ether polyoxypropylene ether base oil in Comparative Example 1 was purchased from Nanjing Will or Zhejiang Huangma Company. The ethylene oxide content of the polyoxyethylene ether polyoxypropylene ether base oil was 40wt%, and the kinematic viscosity at 40°C was 230mm 2 / s.

[0051] The ethylene oxide content of polyoxyethylene ether polyoxypropylene ether base oil was determined by hydrogen nuclear magnetic resonance spectroscopy and carbon nuclear magnetic resonance spectroscopy.

[0052] The kinematic viscosity of the polyoxyethylene ether polyoxypropylene ether base oil and the compressor oil composition at 40°C is measured in accordance with GB / T265-1988 Petroleum Products Kinematic Viscosity Determination and Dynamic Viscosity Calculation Method; the viscosity index is measured in accordance with GB / T1995-1998 Petroleum Products Viscosity Index Counting Method.

[0053] Unless otherwise specified, all raw materials were commercially available.

[0054] Example 1

[0055] 99 parts by weight of polyoxyethylene ether polyoxypropylene ether base oil were added to a mixing kettle, followed by 0.9 parts by weight of an antioxidant (alkylene monophenol) and 0.1 parts by weight of a rust inhibitor (benzotriazole). The mixture was mechanically stirred at 110°C and -0.95 MPa for 3 hours to obtain an ethylene compressor oil composition A1.

[0056] Example 2

[0057] 98 parts by weight of polyoxyethylene ether polyoxypropylene ether base oil were added to a mixing kettle, followed by 1.8 parts by weight of an antioxidant (alkylamine and alkylene monophenol compounded in a mass ratio of 1:1) and 0.2 parts by weight of a rust inhibitor (methylbenzotriazole). The mixture was mechanically stirred at 115°C and -0.94 MPa for 2.5 hours to obtain an ethylene compressor oil composition A2.

[0058] Example 3

[0059] 96 parts by weight of polyoxyethylene ether polyoxypropylene ether base oil were added to a mixing kettle, followed by 2.5 parts by weight of an antioxidant (alkylamine) and 1.5 parts by weight of a rust inhibitor (benzotriazole and methylbenzotriazole in a mass ratio of 1:1). The mixture was mechanically stirred at 120°C and -0.97 MPa for 2 hours to obtain an ethylene compressor oil composition A3.

[0060] Example 4

[0061] The method of Example 1 was followed, except that trioctyl phosphite was used as the antioxidant, to obtain ethylene compressor oil composition A4.

[0062] Example 5

[0063] The method of Example 1 was followed, except that the rust inhibitor was benzimidazole, to obtain an ethylene compressor oil composition A5.

[0064] Example 6

[0065] The method of Example 1 was followed, except that the content of the polyether base oil was 90 parts by weight and the content of the antioxidant was , to obtain an ethylene compressor oil composition A6.

[0066] Example 7

[0067] An ethylene compressor oil composition A7 was obtained by following the method of Example 1, except that the content of the antioxidant was 0 parts by weight.

[0068] Example 8

[0069] An ethylene compressor oil composition A8 was obtained by following the method of Example 1, except that the content of the rust inhibitor was 0 parts by weight.

[0070] Comparative Example 1

[0071] An ethylene compressor oil composition B1 was obtained by following the method of Example 1, except that the base oil was a polyoxyethylene ether polyoxypropylene ether base oil having an ethylene oxide content of 40 wt%.

[0072] Comparative Example 2

[0073] An ethylene compressor oil composition B2 was obtained by following the method of Example 1, except that the polyether base oil was replaced by a mineral base oil (100# industrial white oil).

[0074] Test Case

[0075] The lubricating oil properties, viscosity-temperature properties, anti-wear properties and copper corrosion resistance of the ethylene compressor oil compositions A1-A8 and B1-B2 in Examples 1-8 and Comparative Examples 1-2 were tested, respectively. The results are shown in Table 1.

[0076] The kinematic viscosity of the ethylene compressor oil composition at 40° C. is measured in accordance with GB / T 265-1988 Petroleum Products Kinematic Viscosity Determination and Dynamic Viscosity Calculation Method.

[0077] The viscosity index of the ethylene compressor oil composition is measured in accordance with GB / T 1995-1998 Viscosity Index Counting Method for Petroleum Products.

[0078] The lubricating properties of ethylene compressor oil shall be in accordance with GB / T 3142 Determination of load-carrying capacity of lubricants - Four-ball method.

[0079] The anti-wear performance of ethylene compressor oil is determined according to "NB / SH / T 0189 Determination of Anti-wear Performance of Lubricating Oils - Four-ball Method".

[0080] The copper corrosion resistance of ethylene compressor oil is determined according to a self-developed method. The specific method includes placing tin bronze in a sealed container containing ethylene compressor oil and a certain amount of acetic acid, immersing it at a certain temperature for a certain period of time, and weighing the mass loss of the tin bronze before and after the test as the basis for determining the corrosion of the tin bronze, in mg.

[0081] Table 1

[0082]

[0083] Table 1 (continued)

[0084]

[0085]

[0086] The results in Table 1 show that the ethylene compressor oil compositions prepared in Examples 1-3 have excellent lubricating oil properties (high kinematic viscosity at 40°C), viscosity-temperature performance (high viscosity index), anti-wear performance (sintering load and wear spot diameter), and copper corrosion resistance, especially excellent resistance to copper component corrosion in an acetic acid environment. However, the use of a phosphite antioxidant in Example 4 and a benzimidazole rust inhibitor in Example 5 both resulted in decreased copper corrosion resistance in the ethylene compressor oil compositions. Reducing the amount of polyether base oil in Example 6 resulted in decreased copper corrosion resistance in the ethylene compressor oil composition. No antioxidant or rust inhibitor was added in Examples 7-8, respectively, resulting in a significant decrease in copper corrosion resistance in the ethylene compressor oil composition. Comparative Example 1 used a polyether with a low ethylene oxide content as the base oil, resulting in a significant decrease in the viscosity index and copper corrosion resistance of the ethylene compressor oil composition. Comparative Example 2 used industrial white oil as the base oil, resulting in a significant decrease in the lubricating oil properties, viscosity-temperature performance, anti-wear performance, and copper corrosion resistance of the ethylene compressor oil composition.

[0087] In summary, the ethylene compressor oil composition prepared by the present invention has excellent lubricity, viscosity-temperature properties, anti-wear performance, and copper corrosion resistance, especially excellent resistance to copper component corrosion in an acetic acid environment. It can provide good lubrication and sealing effects for the cylinder and packing of the ultra-high pressure ethylene compressor for producing EVA, ensuring the normal operation of the unit.

[0088] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, various simple variations of the technical solution of the present invention may be made, including combining the various technical features in any other appropriate manner. These simple variations and combinations should also be regarded as disclosed in the present invention and fall within the scope of protection of the present invention.

Claims

1. A compressor oil composition, characterized in that The compressor oil composition comprises: a polyether base oil, an antioxidant and a rust inhibitor; Wherein, the polyether base oil is selected from polyoxyethylene ether polyoxypropylene ether base oil; Wherein, the ethylene oxide content of the polyoxyethylene ether polyoxypropylene ether base oil is greater than 50wt%.

2. The compressor oil composition according to claim 1, wherein Based on the mass of the compressor oil composition, the content of the polyether base oil is 95wt%-99.8wt%, the content of the antioxidant is 0.1wt%-2.5wt%, and the content of the rust inhibitor is 0.1wt%-2.5wt%; Preferably, based on the mass of the compressor oil composition, the content of the polyether base oil is 96wt%-99wt%, the content of the antioxidant is 0.9wt%-2.5wt%, and the content of the rust inhibitor is 0.1wt%-1.5wt%.

3. The compressor oil composition according to claim 1 or 2, wherein The kinematic viscosity of the compressor oil composition at 40° C. is 250-280 mm 2 / s, viscosity index is 230-260.

4. The compressor oil composition according to any one of claims 1 to 3, wherein The antioxidant is selected from amine antioxidants and / or phenolic antioxidants; Preferably, the amine antioxidant is selected from alkylamines and / or aromatic amines; Preferably, the phenolic antioxidant is selected from alkylene monophenols and / or alkylene bisphenols.

5. The compressor oil composition according to any one of claims 1 to 4, wherein The rust inhibitor is selected from benzotriazole and / or benzotriazole derivatives.

6. A method for preparing a compressor oil composition, characterized in that: The method comprises: mixing a polyether base oil, an antioxidant and a rust preventive under vacuum conditions to obtain a compressor oil composition.

7. The method according to claim 6, wherein: The mixing conditions include: temperature of 100-120° C. and time of 2-4 hours.

8. The method according to claim 6, wherein: The vacuum degree of the vacuum condition is -0.97 MPa to -0.92 MPa.

9. A compressor oil composition prepared by the method according to any one of claims 6 to 8; Preferably, the kinematic viscosity of the compressor oil composition at 40°C is 250-280 mm 2 / s, viscosity index is 230-260.

10. Use of the compressor oil composition according to any one of claims 1 to 5 and 9 for improving the copper corrosion resistance of an ultra-high pressure ethylene compressor in an acetic acid atmosphere.

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