Environment-friendly biodegradable lubricating oil for hydraulic retarder and preparation method thereof

Abstract

The application belongs to the technical field of lubricating oil, and particularly relates to an environmentally-friendly biodegradable lubricating oil for a hydraulic retarder and a preparation method thereof. The environmentally-friendly biodegradable lubricating oil for the hydraulic retarder comprises the following components in parts by mass: base oil 80-90 parts, cleaning agent 1-3 parts, dispersant 1-3 parts, viscosity index improver 1-2 parts, anti-wear agent 0.5-2 parts, antioxidant 0.3-1.5 parts, anti-foaming agent 0.1-0.5 parts, and pour point depressant 0.1-0.3 parts. The antioxidant comprises a hindered phenolic ester, an aromatic amine and a zinc salt of a sulfur phosphoric acid in a mass ratio of 3-6:2-5:1. The environmentally-friendly biodegradable lubricating oil for the hydraulic retarder is biodegradable, has excellent high-temperature oxidation resistance and low-temperature resistance, and has a longer oil change period.

Description

Technical Field

[0001] This invention belongs to the field of lubricating oil technology, specifically relating to an environmentally friendly biodegradable lubricating oil for hydraulic retarders and its preparation method. Background Technology

[0002] The transportation industry has increasingly stringent requirements for payload, mileage, and average speed, leading to continuous increases in engine power. However, in certain special operating conditions (such as mountainous, hilly, and plateau regions), the effectiveness of service brakes is limited, thus affecting vehicle safety. A hydraulic retarder is an auxiliary braking device developed to address this need. Through a rotor within the retarder driving the hydraulic fluid to impact the stator, it converts the vehicle's kinetic energy into heat in the hydraulic fluid, reducing the burden on the service brakes, ensuring safe driving, and lowering fuel consumption.

[0003] Traditional automotive hydraulic retarders typically use engine oil or ordinary gear oil as lubricant. However, engine oil or ordinary gear oil has poor shear resistance and its viscosity drops too quickly, leading to a decrease in the efficiency of the hydraulic retarder.

[0004] Chinese Patent Publication No. CN 114381318 A discloses a lubricating oil composition for a hydraulic retarder. The lubricating oil composition comprises: (A) at least one high viscosity index hydrorefined Group III base oil, or hydrorefined naphthenic base oil, or any combination of the above components; (B) at least one phosphorus-containing anti-wear agent; (C) at least one ashless dispersant; (D) at least one antioxidant; (E) at least one metal deactivator; and (F) at least one antifoaming agent. Chinese Patent Publication No. CN 117925300 A discloses a hydraulic retarder lubricating oil composition and its preparation method, comprising the following components by weight: 0.01–6.5 parts detergent-dispersant, 0.1–2.0 parts antioxidant, 0.1–2.5 parts phosphorus-containing anti-wear agent, 0.01–1.0 parts metal deactivator, 0.01–0.5 parts pour point depressant, 0.01–0.1 parts antifoaming agent, 0.1–20.0 parts viscosity index improver, and 60–85 parts base oil; wherein the base oil is composed of hydrogenated base oil and ester base oil in a weight ratio of 4–24:1. However, the low-temperature resistance, thermal oxidation stability, and antifoaming properties of the above technical solution need to be improved. Summary of the Invention

[0005] The present invention aims to solve one or more technical problems existing in the prior art, and at least provide a beneficial solution. Specifically, the present invention provides an environmentally friendly biodegradable lubricating oil for hydraulic retarders and its preparation method, which is biodegradable and has excellent high-temperature resistance, oxidation resistance, low-temperature resistance, and longer oil change intervals.

[0006] On one hand, the present invention provides an environmentally friendly, biodegradable lubricating oil for hydraulic retarders, comprising the following components in parts by weight: Base oil 80-90 parts, detergent 1-3 parts, dispersant 1-3 parts, viscosity index improver 1-2 parts, anti-wear agent 0.5-2 parts, antioxidant 0.3-1.5 parts, antifoaming agent 0.1-0.5 parts, pour point depressant 0.1-0.3 parts; The antioxidant comprises hindered phenolic esters, aromatic amines, and zinc thiophosphate in a mass ratio of 3-6:2-5:1.

[0007] As an example, the mass fraction of the base oil can be any one of 80 parts, 82 parts, 84 parts, 86 parts, 88 parts, or 90 parts, or a range of any two of these values.

[0008] In some preferred embodiments, the base oil comprises diesters, saturated polyol esters, and benzene polyesters.

[0009] In some preferred embodiments, the mass ratio of the diester, saturated polyol ester and phenyl polyester is 2-4:3-6:1.

[0010] In a preferred embodiment, the mass ratio of the diester, saturated polyol ester, and phenyl polyester is 3:5:1.

[0011] In some preferred embodiments, the diester is selected from Priolube. TM 1936 and PriEco ® At least one of those in 2006.

[0012] In some preferred embodiments, the saturated polyol ester is selected from Priolube. TM 3970, Priolube TM 2720 ​​and Priolube TM At least one of those from 1937.

[0013] In some preferred embodiments, the polyphenol ester is selected from PriEco. ® 8005A, PriEco ® 8005 and PriEco ® At least one of 8004.

[0014] As an example, the mass fraction of the cleaning agent can be any one of the following values: 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, or a range of any two values.

[0015] In some preferred embodiments, the cleaning agent is selected from at least one of calcium petroleum sulfonate, calcium alkyl salicylate, and calcium alkylphenol sulfide.

[0016] As an example, the mass fraction of the dispersant can be any one of 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, or a range of any two points.

[0017] In some preferred embodiments, the dispersant is selected from at least one of polyisobutylene succinimide, ashless phosphate, and succinimide.

[0018] As an example, the mass fraction of the viscosity index improver can be any one of the following values: 1 part, 1.2 parts, 1.5 parts, 1.8 parts, 2 parts, or a range of any two values.

[0019] In some preferred embodiments, the viscosity index improver is selected from at least one of polyisobutylene, methacrylate polymers, and ethylene distearate.

[0020] As an example, the mass fraction of the anti-wear agent can be any one of the following values: 0.5 parts, 0.8 parts, 1.2 parts, 1.5 parts, 1.8 parts, 2 parts, or a range of any two values.

[0021] In some preferred embodiments, the anti-wear agent comprises oleyl alcohol polyoxyethylene ether phosphate and molybdenum dialkyl dithiocarbamate in a mass ratio of 1-2:1-2.

[0022] As an example, the mass fraction of the antioxidant can be any one of the following values, or a range of any two values: 0.3 parts, 0.5 parts, 0.8 parts, 1 part, 1.2 parts, and 1.5 parts.

[0023] In a preferred embodiment, the hindered phenolic ester is ETHANOX. @ 4716.

[0024] In some preferred embodiments, the zinc thiophosphate salt is selected from at least one of the following: dioctyl basic zinc thiophosphate, octyl thiophosphate secondary alkyl zinc phosphate, octyl thiophosphate primary alkyl zinc phosphate, and octyl thiophosphate primary alkyl zinc phosphate.

[0025] In some preferred embodiments, the aromatic amine has the following structural formula: .

[0026] As an example, the mass fraction of the antifoaming agent can be any one of 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, or 0.5 parts, or a range of any two of these values.

[0027] In some preferred embodiments, the antifoaming agent is selected from at least one of methyl silicone oil, methyl silicone ester, and polyacrylate.

[0028] As an example, the mass fraction of the pour point depressant can be any one of 0.1 parts, 0.2 parts, or 0.3 parts, or a range of any two of these values.

[0029] In some preferred embodiments, the pour point depressant is selected from at least one of polymethyl methacrylate alkyl ester, ethylene-vinyl acetate copolymer, and fumarate-vinyl acetate copolymer.

[0030] In some preferred embodiments, the mass ratio of the anti-wear agent, antioxidant, and anti-foaming agent is 3-5:2-4:1.

[0031] On the other hand, the present invention provides a method for preparing the above-mentioned environmentally friendly biodegradable lubricating oil for hydraulic retarder, comprising the following steps: first, stirring the base oil, detergent, dispersant, viscosity index improver, anti-wear agent, antioxidant, and pour point depressant evenly, and then adding an antifoaming agent and stirring evenly to obtain the product.

[0032] In some preferred embodiments, the preparation method of the environmentally friendly biodegradable lubricating oil for the hydraulic retarder includes the following steps: first, heating the base oil to 60-65°C, adding detergent, dispersant, viscosity index improver, anti-wear agent, antioxidant, and pour point depressant, stirring evenly at 30-50 rpm for 20-30 minutes, and then adding antifoaming agent and stirring for 5-10 minutes to obtain the final product.

[0033] Compared with the prior art, the present invention has the following beneficial effects: Existing lubricating oils for hydraulic retarders have the following technical problems: 1. It lacks biodegradability, which does not meet the requirements of green development. Furthermore, to ensure the normal operation of the hydraulic retarder, the lubricating oil used in the hydraulic retarder needs to have good viscosity and flow properties in high and low temperature environments. To address the above technical problems, this invention, through the selection of biodegradable base oils, discovered that using a blend of diesters, saturated polyol esters, and phenyl polyesters as the base oil results in a lubricant with high viscosity index, low-temperature resistance, high-temperature anti-foaming resistance, and thermal oxidation stability.

[0034] 2. When the hydraulic retarder is working, the kinetic energy of the vehicle is transferred to the stator via the rotor, which in turn drives the lubricating oil, causing the lubricating oil temperature to rise rapidly. This makes the base oil prone to oxidation and deterioration, thus requiring the lubricating oil to have good resistance to high-temperature oxidation. To address this technical problem, the inventors discovered through experimentation that when hindered phenolic esters, aromatic amines, and zinc thiophosphates are compounded in a mass ratio of 3-6:2-5:1, the resulting lubricating oil, after a 192-hour thermal oxidation stability test at 160°C, exhibits a kinematic viscosity change rate of less than 6% at 40°C, a kinematic viscosity change rate of less than 5% at 100°C, an acid value change of less than 0.3 mg KOH / g, and a clean and bright appearance.

[0035] 3. Although hydraulic retarders can be considered as wear-free auxiliary braking components, to improve the oil change interval of commercial vehicles and construction machinery operating under various harsh conditions, the lubricating oil is required to have good anti-wear properties. Simultaneously, the rotor of the hydraulic retarder is in a rotating and agitated state during operation, thus requiring the lubricating oil to have good anti-foaming properties. Regarding the above technical problems, the inventors, through experimental research, discovered that when using an anti-wear agent comprising oleoyl alcohol polyoxyethylene ether phosphate and molybdenum dialkyl dithiocarbamate in a mass ratio of 1-2:1-2, and controlling the mass ratio of anti-wear agent, antioxidant, and anti-foaming agent to 3-5:2-4:1, the resulting environmentally friendly biodegradable lubricating oil for hydraulic retarders exhibits excellent anti-wear, anti-foaming, and thermal oxidation stability.

[0036] 4. The environmentally friendly biodegradable lubricating oil for the hydraulic retarder provided by this invention has been verified by automotive OEMs under various operating conditions, such as a 100,000 km oil change period for heavy trucks in the Yunnan plateau region, through slow-speed driving tests. Attached Figure Description

[0037] Figure 1 The images show the appearance of the environmentally friendly biodegradable lubricating oil for the hydraulic retarder in Examples 2 (left) and 3 (right) of the present invention after a thermal oxidation stability test. Figure 2 This is a diagram showing the appearance of the environmentally friendly biodegradable lubricating oil for the hydraulic retarder of Comparative Example 2 of the present invention after a thermal oxidation stability test. Figure 3 The performance test results of the environmentally friendly biodegradable lubricating oil for the hydraulic retarder in Embodiment 3 of the present invention are presented. Detailed Implementation

[0038] To enable those skilled in the art to more clearly understand the technical solutions described in this invention, the following embodiments are provided for illustration. It should be noted that the following embodiments do not constitute a limitation on the scope of protection claimed by this invention.

[0039] Unless otherwise specified, the raw materials, reagents or apparatus used in the following examples and comparative examples are available from conventional commercial sources or can be obtained by existing known methods.

[0040] Example 1 This embodiment provides an environmentally friendly, biodegradable lubricating oil for hydraulic retarders, with the following composition by weight: The ingredients are: 85 parts base oil, 2 parts detergent, 2 parts dispersant, 1.5 parts viscosity index improver, 1.5 parts anti-wear agent, 1 part antioxidant, 0.4 parts antifoaming agent, and 0.2 parts pour point depressant.

[0041] The base oil is a diester, a saturated polyol ester, and a benzene polyester in a mass ratio of 3:5:1.

[0042] The diester is Priolube. TM 1936, originating from Dongguan Hongli Chemical Technology Co., Ltd.

[0043] The saturated polyol ester is Priolube. TM 3970 originates from Dongguan Hongli Chemical Technology Co., Ltd.

[0044] The polyphenol ester is PriEco ® 8005A is from Shanghai Daopu Chemical Co., Ltd.

[0045] The cleaning agent is calcium alkylphenol sulfide, sourced from Nanjing Shouqianshou Chemical Technology Co., Ltd., model number: T123.

[0046] The dispersant is polyisobutylene succinimide, sourced from Nanjing Shouqianshou Chemical Technology Co., Ltd., model number: T154.

[0047] The viscosity index improver is a methacrylate polymer, brand name: Irgaflo. ® 1100V, sourced from Dongguan Hongli Chemical Technology Co., Ltd.

[0048] The anti-wear agent is oleyl alcohol polyoxyethylene ether phosphate and molybdenum dialkyl dithiocarbamate in a mass ratio of 1:1.

[0049] The oleyl alcohol polyoxyethylene ether phosphate, brand name: Solvay LUBRHOPHOS ® LB-400 is sourced from Dongguan Hongli Chemical Technology Co., Ltd.

[0050] The molybdenum dialkyl dithiocarbamate is sourced from Jinzhou Chenghua New Materials Co., Ltd., model number: MO-10.

[0051] The antioxidant is a hindered phenolic ester, an aromatic amine, and a zinc thiophosphate in a mass ratio of 5:3:1.

[0052] The hindered phenolic ester is ETHANOX. ® 4716, originating from Guangzhou Qisheng Trading Co., Ltd.

[0053] The zinc thiophosphate salt is a thiophosphate dioctyl basic zinc salt, sourced from Shenyang Hualun Lubricating Oil Additives Co., Ltd., model number: T203.

[0054] The structural formula of the aromatic amine is as follows: Sourced from Tianjin Lialong New Material Co., Ltd., Model: RIANOX ® 5057.

[0055] The antifoaming agent is methyl silicone oil, sourced from Jinzhou Shengda Chemical Co., Ltd., model number: T-901.

[0056] The pour point depressant is a fumarate-vinyl acetate copolymer, sourced from Jinzhou Shengda Chemical Co., Ltd., model number: T-816A.

[0057] The preparation method of the above-mentioned environmentally friendly biodegradable lubricating oil for hydraulic retarder is as follows: first, heat the base oil to 60°C, add detergent, dispersant, viscosity index improver, anti-wear agent, antioxidant, and pour point depressant, stir evenly at 50 rpm for 20 minutes, and then add antifoaming agent and stir for 10 minutes to obtain the product.

[0058] Example 2 This embodiment provides an environmentally friendly biodegradable lubricating oil for hydraulic retarders. The difference from Embodiment 1 is that, by weight, its composition is as follows: 80 parts base oil, 1 part detergent, 1 part dispersant, 1 part viscosity index improver, 0.5 parts anti-wear agent, 0.5 parts antioxidant, 0.2 parts antifoaming agent, and 0.1 parts pour point depressant; the rest are the same.

[0059] Example 3 This embodiment provides an environmentally friendly biodegradable lubricating oil for hydraulic retarders. The difference from Embodiment 1 is that, by weight, its composition is as follows: 90 parts base oil, 3 parts detergent, 3 parts dispersant, 2 parts viscosity index improver, 2 parts anti-wear agent, 1.5 parts antioxidant, 0.5 parts antifoaming agent, and 0.3 parts pour point depressant; the rest are the same.

[0060] Example 4 This embodiment provides an environmentally friendly biodegradable lubricating oil for hydraulic retarders. The difference from Embodiment 1 is that the base oil is a diester and a saturated polyol ester with a mass ratio of 3:6; all other aspects are the same.

[0061] Example 5 This embodiment provides an environmentally friendly, biodegradable lubricating oil for hydraulic retarders. The only difference from Embodiment 3 is that the anti-wear agent is oleyl alcohol polyoxyethylene ether phosphate; all other aspects are the same.

[0062] Example 6 This embodiment provides an environmentally friendly biodegradable lubricant for hydraulic retarders. The only difference from Embodiment 3 is that the oleyl alcohol polyoxyethylene ether phosphate is replaced with an equal mass of isooctyl phosphite, which is sourced from Wuhan Xindadi Environmental Protection Materials Co., Ltd., model: DURAPHOS B(2EH)HP.

[0063] Comparative Example 1 This comparative example provides an environmentally friendly, biodegradable lubricant for hydraulic retarders. The only difference from Example 3 is that the antioxidant is a hindered phenolic ester and zinc thiophosphate in a mass ratio of 5:4; all other aspects are the same.

[0064] Comparative Example 2 This comparative example provides an environmentally friendly, biodegradable lubricant for a hydraulic retarder. The only difference from Example 3 is that the antioxidant is an aromatic amine and zinc thiophosphate salt in a mass ratio of 8:1; all other aspects are the same.

[0065] Comparative Example 3 This comparative example provides an environmentally friendly, biodegradable lubricant for hydraulic retarders, differing from Example 3 only in that it contains hindered phenolic ester ETHANOX. ® 4716 was replaced with an equivalent mass of phenolic ester IRGANOX. ® L135; all others are the same.

[0066] Comparative Example 4 This comparative example provides an environmentally friendly, biodegradable lubricating oil for hydraulic retarders. The only difference from Example 3 is that the aromatic amine used is nonyl-N-(nonylphenyl)aniline, sourced from Tianjin Lianlong New Material Co., Ltd., model number: RIANOX. ® 5067; the rest are the same.

[0067] Performance Test 1: The hydraulic retarders prepared in Examples 1-6 were subjected to performance testing using environmentally friendly biodegradable lubricating oil. Specific test methods and results are shown in Table 1 below. Figure 1 .

[0068] Table 1 As shown in Table 1, the environmentally friendly biodegradable lubricating oils for hydraulic retarders in Examples 1 and 3 exhibit excellent viscosity index, low-temperature resistance, anti-foaming properties, load-carrying capacity, and thermal oxidation stability. The performance of the environmentally friendly biodegradable lubricating oil for hydraulic retarders in Example 2 is worse than that in Examples 1 and 3. In Example 4, due to the absence of phenyl polyester, the excellent viscosity index, low-temperature resistance, high-temperature foaming properties, load-carrying capacity, and thermal oxidation stability of the environmentally friendly biodegradable lubricating oil for hydraulic retarders are significantly worse. In Example 5, due to the absence of molybdenum dialkyl dithiocarbamate, the high-temperature foaming properties, load-carrying capacity, and thermal oxidation stability of the environmentally friendly biodegradable lubricating oil for hydraulic retarders are significantly worse. In Example 6, due to the replacement of oleyl alcohol polyoxyethylene ether phosphate with an equal mass of isooctyl phosphite, the anti-foaming properties, high-temperature foaming properties, load-carrying capacity, and thermal oxidation stability of the environmentally friendly biodegradable lubricating oil for hydraulic retarders are significantly worse.

[0069] Depend on Figure 1It can be seen that the environmentally friendly biodegradable lubricating oil used in the hydraulic retarder of Example 2 showed impurities after the thermal oxidation stability test, resulting in poor performance; while the environmentally friendly biodegradable lubricating oil used in the hydraulic retarder of Example 3 remained clean and bright after the thermal oxidation stability test.

[0070] Performance Test 2: The hydraulic retarders prepared in Comparative Examples 1-4 were subjected to performance testing using environmentally friendly biodegradable lubricating oil. Specific test methods and results are shown in Table 2 below. Figure 2 .

[0071] Table 2 As can be seen from Table 2, Comparative Example 1 was exempt from the presence of aromatic amines, Comparative Example 2 was exempt from the presence of hindered phenolic esters, and Comparative Example 3 was exempt from the presence of hindered phenolic ester ETHANOX. ® 4716 was replaced with phenolic ester IRGANOX. ® L135; Comparative Example 4, due to the addition of aromatic amine RIANOX ® 5057 replaced with RIANOX ® 5067, the thermal oxidation stability of the environmentally friendly biodegradable lubricating oil used in the hydraulic retarder was significantly worse.

[0072] Depend on Figure 2 It can be seen that the environmentally friendly biodegradable lubricating oil used in the hydraulic retarder of Comparative Example 2 showed obvious oxidation, dark color, and lack of transparency after the thermal oxidation stability test.

[0073] Performance Test 3: The hydraulic retarder prepared in Example 3 was subjected to performance testing using an environmentally friendly biodegradable lubricating oil. The specific test methods and results are as follows. Figure 2 As shown.

[0074] Depend on Figure 2 It can be seen that the environmentally friendly biodegradable lubricating oil for the hydraulic retarder in Embodiment 3 of the present invention also has a high flash point, no smoke, and no carbon buildup.

[0075] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, and is not intended to limit the scope of protection of the present invention. Simple modifications or equivalent substitutions made by those skilled in the art to the technical solution of the present invention do not depart from the essence and scope of the technical solution of the present invention.

Claims

1. An environmentally friendly, biodegradable lubricating oil for hydraulic retarders, characterized in that, The components include the following parts by weight: Base oil 80-90 parts, detergent 1-3 parts, dispersant 1-3 parts, viscosity index improver 1-2 parts, anti-wear agent 0.5-2 parts, antioxidant 0.3-1.5 parts, antifoaming agent 0.1-0.5 parts, pour point depressant 0.1-0.3 parts; The base oil includes diesters, saturated polyol esters, and phenyl polyesters; The anti-wear agent comprises oleyl alcohol polyoxyethylene ether phosphate and molybdenum dialkyl dithiocarbamate in a mass ratio of 1-2:1-2; The antioxidant comprises hindered phenolic esters, aromatic amines, and zinc thiophosphate in a mass ratio of 3-6:2-5:1; The hindered phenolic ester is ETHANOX. ® 4716; The aromatic amine is RIANOX. ® 5057.

2. The environmentally friendly biodegradable lubricating oil for hydraulic retarders according to claim 1, characterized in that, The diester is selected from Priolube. TM 1936 and PriEco ® At least one of 2006; the saturated polyol ester is selected from Priolube. TM 3970, Priolube TM 2720 ​​and Priolube TM At least one of 1937; the phenyl polyester is selected from PriEco ® 8005A, PriEco ® 8005 and PriEco ® At least one of 8004.

3. The environmentally friendly biodegradable lubricating oil for hydraulic retarders according to claim 1, characterized in that, The cleaning agent is selected from at least one of calcium petroleum sulfonate, calcium alkyl salicylate, and calcium alkylphenol sulfide; the dispersant is selected from at least one of polyisobutylene succinimide, ashless phosphate, and succinimide; and the viscosity index improver is selected from at least one of polyisobutylene, methacrylate polymer, and ethylene bis-stearamide.

4. The environmentally friendly biodegradable lubricating oil for hydraulic retarders according to claim 1, characterized in that, The zinc thiophosphate salt is selected from at least one of the following: dioctyl basic zinc thiophosphate, octyl thiophosphate, octyl thiophosphate, and octyl thiophosphate.

5. The environmentally friendly biodegradable lubricating oil for hydraulic retarders according to any one of claims 1-4, characterized in that, The mass ratio of the anti-wear agent, antioxidant, and anti-foaming agent is 3-5:2-4:

1.

6. The method for preparing the environmentally friendly biodegradable lubricating oil for hydraulic retarders according to any one of claims 1-4, characterized in that, The process includes the following steps: First, mix the base oil, detergent, dispersant, viscosity index improver, anti-wear agent, antioxidant, and pour point depressant evenly, then add the antifoaming agent and mix evenly to obtain the final product.

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