CN107974328B

CN107974328B - Lubricating oil composition and method for improving wear resistance and friction reduction performance of lubricating oil

Info

Publication number: CN107974328B
Application number: CN201610941461.8A
Authority: CN
Inventors: 张辉; 段庆华; 苏朔
Original assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Current assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Priority date: 2016-10-25
Filing date: 2016-10-25
Publication date: 2021-06-11
Anticipated expiration: 2036-10-25
Also published as: CN107974328A

Abstract

The invention provides a lubricating oil composition and a method for improving the wear resistance and the antifriction performance of lubricating oil. The lubricating oil composition comprises 0.1-5% of antioxidant antiwear agent, 3-15% of viscosity index improver, 1-10% of dispersant, 1-15% of detergent, 0.1-5% of antioxidant, 0.1-5% of oiliness agent and the balance of lubricating base oil; the preparation method of the antioxidant antiwear agent comprises the following steps: reacting thiophosphoric acid with peroxide, then performing saponification reaction with a zinc-containing compound, and collecting an oil phase product. The antioxidant antiwear agent and the lubricating oil composition have excellent wear resistance and friction reduction performance, and can prolong the service life of oil products.

Description

Lubricating oil composition and method for improving wear resistance and friction reduction performance of lubricating oil

Technical Field

The invention relates to a lubricating oil composition, in particular to a lubricating oil composition with excellent wear resistance and friction reduction performance.

Background

The lubricating oil inevitably contacts with oxygen in the air and the metal surface to generate oxidation reaction and deteriorate in the using process, so that the viscosity of the oil is increased, the acid value is increased, oil sludge and sediment are generated, and corrosion and abrasion are generated on metal parts. In order to prolong the service life of the oil product, delay the oxidation process of the oil product and slow down the friction and wear of equipment, an antioxidant and an antiwear agent can be added into the oil product, so that the oxidation reaction of the oil product can be effectively inhibited, and the service performance of the oil product is improved.

It is well known that zinc dialkyldithiophosphates (ZDDP) have excellent antioxidant, anti-corrosion and anti-wear properties and have been widely used in various lubricating oils since their development in the last 40 th century, especially in internal combustion engine oils. In fact, the term "zinc dialkyldithiophosphate" is intended to encompass a range of compounds, the differences between which are primarily in the different alkyl components and the relative spatial relationship of the alkyl components around the phosphorus molecule. Thus, zinc dialkyldithiophosphates of different structures may have different performance properties in a lubricant. In recent years, with the rapid development of the automobile industry, increasingly stringent requirements are placed on lubricating oil additives (including ZDDP), especially in the aspect of gasoline engine oil, the phosphorus content is gradually reduced from 0.12% to 0.06%, so that the requirement of reducing the use amount of ZDDP in internal combustion engine oil is urgent, and the development of dialkyl dithiophosphate derivatives with good oxidation and abrasion resistance is urgently required, and the requirement of good performance under the condition of reduced dosage is still required. Meanwhile, an excessively high Zn/P ratio can lead to more metal content in the lubricating oil product when the same phosphorus content is provided, can lead to more particles contained in the exhaust emission, and is not favorable for environmental protection.

Chinese patent CN 101659896 adopts methyl isobutyl carbinol type zinc dialkyl dithiophosphate to solve the problem of phosphorus volatility, reduces the phosphorus volatility and the generation amount of deposits of engine oil, but the price of the raw material methyl isobutyl carbinol is higher.

U.S. Pat. No. 4, 5728656 discloses a super-neutral zinc dialkyldithiophosphate having a Zn/P ratio of between 0.95 and 1.04. The product has more neutral salt components and good wear resistance and corrosion resistance.

Chinese patent CN 1769405A discloses a preparation method of zinc dialkyl dithiophosphate for improving rubber seal compatibility. In the patent, phosphorus pentoxide is introduced in the preparation process of the dialkyl dithiophosphoric acid, and finally the modified zinc dialkyl dithiophosphate product is obtained by saponification, wherein the product has better compatibility with rubber.

Disclosure of Invention

The invention provides a lubricating oil composition and a method for improving the wear resistance and the antifriction performance of lubricating oil.

The lubricating oil composition of the present invention comprises: 0.1 to 5 percent of antioxidant antiwear additive, 3 to 15 percent of viscosity index improver, 1 to 10 percent of dispersant, 1 to 15 percent of detergent, 0.1 to 5 percent of antioxidant, 0.1 to 5 percent of oiliness agent and the balance of lubricating base oil.

The preparation method of the antioxidant antiwear agent comprises the following steps: reacting thiophosphoric acid with peroxide, then performing saponification reaction with a zinc-containing compound, and collecting an oil phase product.

The structure of the thiophosphoric acid is as follows:

wherein R, R' are each independently selected from C₄～C₃₀Alkyl of (3), preferably C₄～C₁₂Alkyl group of (1).

The peroxide is selected from inorganic peroxides and/or organic peroxides, and examples thereof include hydrogen peroxide, sodium peroxide, potassium peroxide, calcium peroxide, magnesium peroxide, zinc peroxide, potassium peroxymonosulfate, 2-dihydropropane peroxide, 2, 5-dimethyl-2, 5-dihydrohexane peroxide, 2-bis- (t-butylperoxy) propane, 2-bis- (t-butylperoxy) butane, 2, 5-dimethyl-2, 5-bis- (t-butylperoxy) hexane, 2-bis- (4, 4-di-t-butylperoxycyclohexyl) propane, 2, 5-dimethyl-2, 5-bis- (peroxy-2-ethylhexanoyl) hexane, 2, one or more of 5-dimethyl-2, 5-bis- (peroxy-3, 5, 5-trimethylhexanoyl) hexane, 2, 5-dimethyl-2, 5-bis- (peroxyisononyl) hexane and 2, 5-dimethyl-2, 5-bis- (benzoyl peroxide) hexane, one or more of hydrogen peroxide, sodium peroxide, potassium peroxide, 2-dihydropropane peroxide, 2, 5-dimethyl-2, 5-dihydrohexane peroxide, 2-bis- (tert-butylperoxy) propane, 2-bis- (tert-butylperoxy) butane and 2, 5-dimethyl-2, 5-bis- (tert-butylperoxy) hexane are preferred.

The reaction temperature of the thiophosphoric acid and the peroxide is 10-50 ℃, and preferably 20-40 ℃.

The zinc-containing compound is preferably one or more of zinc oxide, zinc hydroxide and zinc acetate, and most preferably zinc oxide.

The temperature of the saponification reaction is 70-100 ℃, and preferably 75-90 ℃. The total mole number of the peroxide and the zinc-containing compound is 50-70%, preferably 55-65% of the mole number of the sulfuric phosphoric acid, wherein the mole ratio of the peroxide to the zinc-containing compound is 1: 20-20: 1, preferably 1: 10-10: 1.

the mass ratio of Zn to P in the antioxidant antiwear agent is 0.01-0.95, preferably 0.1-0.95.

The antioxidant antiwear agent accounts for 0.1-5%, preferably 0.2-4% of the total mass of the lubricating oil composition.

The viscosity index improver is preferably one or more of ethylene-propylene copolymer, polyisobutylene, styrene-butadiene copolymer and polymethacrylate, and most preferably ethylene-propylene copolymer; the viscosity index improver accounts for 3-15%, preferably 5-10% of the total mass of the lubricating oil composition.

The dispersant is preferably a polyisobutylene succinimide dispersant and/or a boron-containing polyisobutylene succinimide dispersant, most preferably a mixture of a polyisobutylene succinimide dispersant and a boron-containing polyisobutylene succinimide dispersant; the dispersant accounts for 1-10%, preferably 2-8% of the total mass of the lubricating oil composition.

The detergent is preferably one or more of a sulphonate, a sulphurised alkyl phenate and a salicylate, preferably a sulphonate and/or a sulphurised alkyl phenate; the detergent accounts for 1-15%, preferably 2-12% of the total mass of the lubricating oil composition.

The antioxidant is preferably an amine antioxidant and/or a phenol antioxidant, and most preferably a mixture of the amine antioxidant and the phenol antioxidant; the antioxidant accounts for 0.1-5%, preferably 0.2-3% of the total mass of the lubricating oil composition.

The oiliness agent is preferably one or more of fatty acid ester, fatty amine, fatty alcohol and dimer acid, and for example, one or more of glyceryl oleate, hexadecylamine, hexadecanol and dimer fatty acid can be selected; the oiliness agent accounts for 0.1-5%, preferably 0.2-3.5% of the total mass of the lubricating oil composition.

The lubricating base oil is selected from one or more of API group I, II, III, IV and V lubricating base oils, preferably one or more of API group I, II, III and IV lubricating base oils.

The invention also provides a method for improving the anti-wear and anti-friction performance of the lubricating oil, which is characterized in that the antioxidant anti-wear agent, the viscosity index improver, the dispersant, the detergent, the antioxidant and the oiliness agent are added into the lubricating oil.

The antioxidant antiwear agent and the lubricating oil composition have excellent wear resistance and friction reduction performance, and can prolong the service life of oil products.

Drawings

FIG. 1 is a nuclear magnetic phosphorus spectrum of an antioxidant antiwear agent sample 1 of the present invention.

FIG. 2 is a nuclear magnetic phosphorus spectrum of comparative sample 1 (T203).

Detailed Description

The invention is further illustrated below by means of specific examples, without being restricted thereto.

The raw material sources are as follows:

t202, zinc butyl/isooctyl dithiophosphate, tin-free south additive plant;

t203, zinc diisooctyl dithiophosphate, tin-free south additive plant;

dimer acid, dimer linoleic acid, peony river daily chemical plant;

monoglycerides of oleic acid, british rice, inc;

hexadecylamine, Beijing reagent Inc.;

cetyl alcohol, Beijing reagent Inc.;

t618, ethylene propylene copolymer viscosity index improver, Nominan petrochemical company;

t152, polyisobutylene succinimide dispersant, tin-free south additive plant;

T161B, boron-containing polyisobutylene succinimide dispersant, tin-free south additive plant;

t107, high base number magnesium sulfonate, langzhou petrochemical additive plant;

t121, medium base sulfurized calcium alkyl phenate, new materials, njiangfeng;

t534, amine antioxidants (butyl/octylated diphenylamine), beijing, khep, fine chemicals ltd;

t512, 3, 5-di-tert-butyl-4-hydroxyphenylpropionic acid isooctyl ester, Beijing Xinpu Fine chemical Co., Ltd.

Example 1 preparation of antioxidant antiwear agent

Adding 141.6g (0.4mol) of diisooctyl dithiophosphoric acid into a 250ml three-neck flask with a stirring device, keeping the temperature at 60 ℃, dropwise adding 5.7g (0.05 mol) of 30% hydrogen peroxide solution within 30 minutes, continuing to react for 2 hours after dropwise adding is finished, then heating to 70 ℃, adding 13.4g (0.165mol) of zinc oxide, heating to 75-90 ℃, reacting for 3-5 hours, continuing to heat to 95-105 ℃, distilling under reduced pressure to remove residual moisture, and filtering to obtain the antioxidant antiwear agent, which is marked as sample 1.

Examples 2-4 preparation of antioxidant antiwear Agents

The antioxidant antiwear agents of the present invention were prepared according to the method of example 1, using thiophosphoric acid of different structures, different molar ratios of thiophosphoric acid to hydrogen peroxide, and different molar ratios of hydrogen peroxide to zinc oxide, and are respectively identified as samples 2-4, and the reaction conditions are shown in table 1.

Comparative samples 1-4 are also listed in Table 1, where comparative sample 1 is a commercial zinc diisooctyl dithiophosphate (C8 primary alcohol ZDDP) having a domestic code number of T203; comparative sample 2 was a commercial zinc butyl/isooctyl dithiophosphate (C4/C8 primary alcohol ZDDP) with a domestic code of T202; comparative sample 3, C3/C6 secondary alcohol ZDDP, was prepared according to the conventional ZDDP method; comparative sample 4 was a C6 secondary alcohol ZDDP, prepared according to conventional ZDDP methods.

The nuclear magnetic phosphorus spectrum test was performed on sample 1 and comparative sample 1(T203) of the antioxidant antiwear agent, and the test instruments and the measurement conditions were as follows: FT-80A NMR apparatus, solvent CCL₄Concentration 50-80%, D₂O lock field, resonance frequency of 32.2MHZ, 5mm sample tube, 85% H₃PO₄Is an external standard. FIG. 1 is a nuclear magnetic phosphorus spectrum of an antioxidant antiwear agent sample 1 of the present invention. FIG. 2 is a nuclear magnetic phosphorus spectrum of comparative sample 1 (T203). As can be seen from the phosphorus spectrograms of the two, the shift is obviously different from 80 ppm to 90 ppm.

The zinc content and the phosphorus content of the antioxidant antiwear agent samples 1-4 and the comparative samples 1-4 are measured by an inductively coupled plasma spectrometer (ICP) method, the mass ratio of Zn to P of each sample is obtained after calculation, and the results are shown in the table 1.

TABLE 1 antioxidant antiwear agent samples 1-4 and comparative samples 1-4

Samples 1 to 4 and comparative samples 1 to 4 were added to 150SN base oil at a dose of 0.5% respectively to prepare examples 5 to 8 and comparative examples 5 to 8 of lubricating oil for testing.

The antioxidant performance of each sample was measured according to the SH/T0193 method for measuring the oxidation stability of lubricating oil (rotating oxygen bomb method). The maximum non-seizure load of each sample was determined according to GB/T3142 lubricating oil carrying capacity determination method (four-ball method). The antiwear properties of the respective samples were measured according to SH/T0189 lube antiwear property measuring method (four-ball method).

The results of the tests on each of the lubricating oil samples are shown in Table 2.

TABLE 2 Performance evaluation

As can be seen from Table 2, the antioxidant antiwear agent with low Zn/P ratio prepared by the invention has better antioxidant and antiwear capabilities, and is obviously superior to the prior Zinc Dialkyl Dithiophosphate (ZDDP) product.

Samples 1 to 4 of an antioxidant antiwear agent with the content of 0.8 percent and comparative samples 1 to 4, an ethylene propylene copolymer viscosity index improver T618 with the content of 7.0 percent, a polyisobutylene succinimide dispersant T152 with the content of 3.5 percent, a polyisobutylene succinimide dispersant T161B with the content of 1.0 percent, magnesium sulfonate with the high base number T107 with the content of 1.0 percent, sulfurized calcium alkyl phenolate with the medium base number T121 with the content of 1.5 percent, an amine antioxidant T534 with the content of 0.3 percent, a phenolic antioxidant T512 with the content of 0.3 percent, an oleic glyceride oiliness agent with the content of 0.5 percent and mineral base oil with the content of 150SN are respectively prepared to obtain examples 9 to 12 and comparative examples 9 to 12 of fully-formulated lubricating oil, and the lubricating oil is subjected to an antioxidant test and an antiwear performance test.

The antioxidant properties of the lubricating oil were measured according to ASTM D7098.

The anti-wear performance of the lubricating oil is measured according to an SH/T0188 method, and the test conditions are as follows: the oil temperature was 54 deg.C, the load was 1335N, and the run time was 60 min.

The results of the antioxidant test and the antiwear property test of examples 9 to 12 and comparative examples 9 to 12 of lubricating oil are shown in Table 3.

TABLE 3 Oxidation and abrasion resistance test results

As can be seen from Table 3, the low Zn/P antioxidant antiwear agent prepared by the present invention has better antioxidant and antiwear properties in the formulation.

Examples 13-16 and comparative examples 13-16 of fully formulated lubricating oil compositions were prepared from antioxidant antiwear agents of the present invention, samples 1-4 of the samples, comparative samples 1-4 of the samples, 7.0% of an ethylene propylene copolymer viscosity index improver T618, 3.5% of a polyisobutylene succinimide dispersant T152, 1.0% of a boron-containing polyisobutylene succinimide dispersant T161B, 1.0% of a high base number magnesium sulfonate T107, 1.5% of a medium base number sulfurized calcium alkyl phenate T121, 0.3% of an amine antioxidant T534, 0.3% of a phenol antioxidant T512, different oiliness agents, and the balance 150SN mineral base oil, respectively, and the types and contents of the antioxidant antiwear agents and the oiliness agents in the compositions are shown in Table 4. The lubricating oils were subjected to the wear resistance and friction reduction tests, and the test results are shown in Table 4.

The friction coefficient was measured using a High Frequency Reciprocating Rig (HFRR) under the following conditions: frequency 20HZ, temperature 50 ℃, load 400g, time 60 min.

TABLE 4

As can be seen from Table 4, the lubricating oil compositions of the present invention have better antiwear and antifriction properties.

Claims

1. A lubricating oil composition comprises, by mass, 0.1-5% of an antioxidant antiwear agent, 3-15% of a viscosity index improver, 1-10% of a dispersant, 1-15% of a detergent, 0.1-5% of an antioxidant, 0.1-5% of an oiliness agent and the balance of lubricating base oil; the preparation method of the antioxidant antiwear agent comprises the following steps: reacting thiophosphoric acid with peroxide, then performing saponification reaction with a zinc-containing compound, and collecting an oil phase product; the total mole number of the peroxide and the zinc-containing compound is 50-70% of the mole number of the sulfuric phosphoric acid, wherein the mole ratio of the peroxide to the zinc-containing compound is 1: 20-20: 1.

2. lubricating oil composition according to claim 1, characterized in that the thiophosphoric acid has the structure:

wherein R, R' are each independently selected from C₄～C₃₀Alkyl group of (1).

3. Lubricating oil composition according to claim 1, characterized in that the peroxide is selected from inorganic peroxides and/or organic peroxides.

4. The lubricating oil composition according to claim 1, wherein the peroxide is selected from the group consisting of hydrogen peroxide, sodium peroxide, potassium peroxide, calcium peroxide, magnesium peroxide, zinc peroxide, potassium peroxymonosulfate, 2-dihydropropane peroxide, 2, 5-dimethyl-2, 5-dihydrohexane peroxide, 2-bis- (t-butylperoxy) propane, 2-bis- (t-butylperoxy) butane, 2, 5-dimethyl-2, 5-bis- (t-butylperoxy) hexane, 2-bis- (4, 4-di-t-butylperoxycyclohexyl) propane, 2, 5-dimethyl-2, 5-bis- (peroxy-2-ethylhexanoyl) hexane, potassium peroxide, calcium peroxide, magnesium peroxide, zinc peroxide, potassium peroxymonosulfate, 2-dihydrohexane peroxide, 2, 5-dimethyl-2, 5-bis- (t-, 2, 5-dimethyl-2, 5-bis- (peroxy-3, 5, 5-trimethylhexanoyl) hexane, 2, 5-dimethyl-2, 5-bis- (peroxyisononyl) hexane and 2, 5-dimethyl-2, 5-bis- (benzoyl peroxide) hexane.

5. The lubricating oil composition according to claim 1, wherein the temperature at which the thiophosphoric acid and the peroxide are reacted is 10 to 50 ℃.

6. The lubricating oil composition of claim 1, wherein the zinc-containing compound is one or more of zinc oxide, zinc hydroxide and zinc acetate.

7. The lubricating oil composition according to claim 1, wherein the saponification reaction temperature is 70 to 100 ℃.

8. The lubricating oil composition according to claim 1, wherein the total mole number of the peroxide and the zinc-containing compound is 55 to 65% of the mole number of the sulfuric phosphoric acid, and the mole ratio of the peroxide to the zinc-containing compound is 1: 10-10: 1.

9. the lubricating oil composition of claim 1, wherein the mass ratio of Zn to P in the antioxidant antiwear agent is between 0.01 and 0.95.

10. The lubricating oil composition of claim 1, wherein the viscosity index improver is selected from one or more of ethylene-propylene copolymers, polyisobutylene, styrene-butadiene copolymers, and polymethacrylates; the dispersant is selected from polyisobutylene succinimide dispersant and/or boron-containing polyisobutylene succinimide dispersant, and the detergent is selected from one or more of sulfonate, sulfurized alkylphenol salt and salicylate; the antioxidant is selected from amine antioxidant and/or phenol antioxidant; the oiliness agent is selected from one or more of fatty acid ester, fatty amine, fatty alcohol and dimer acid.

11. Lubricating oil composition according to claim 1, wherein the lubricating base oil is selected from one or more of the group consisting of API I, II, III, IV and V lubricating base oils.

12. A method for improving the anti-wear and anti-friction properties of the lubricating oil composition according to any one of claims 1 to 11, characterized in that the antioxidant anti-wear agent, the viscosity index improver, the dispersant, the detergent, the antioxidant and the oiliness agent according to any one of claims 1 to 11 are added to the lubricating base oil.