阅读说明：本技术 柴油抗磨剂组合物、其制备方法及柴油组合物 (Diesel antiwear agent composition, preparation method thereof and diesel composition ) 是由 蔺建民 夏鑫 李宝石 李妍 于 2020-03-30 设计创作，主要内容包括：本发明涉及柴油抗磨剂组合物、其制备方法及柴油组合物,所述柴油抗磨剂组合物含有环状二元羧酸单酯化合物,所述环状二元羧酸单酯化合物由C5～C18环状二元羧酸或者酸酐与C1～C30醇或者酚反应制得。本发明提供的柴油抗磨剂效果极好,在柴油中用量很少,可大大降低柴油抗磨剂的使用成本。(The invention relates to a diesel antiwear agent composition, a preparation method thereof and a diesel composition, wherein the diesel antiwear agent composition contains a cyclic dicarboxylic acid monoester compound, and the cyclic dicarboxylic acid monoester compound is prepared by reacting C5-C18 cyclic dicarboxylic acid or anhydride with C1-C30 alcohol or phenol. The diesel antiwear agent provided by the invention has excellent effect, is less in dosage in diesel oil, and can greatly reduce the use cost of the diesel antiwear agent.)

1. A diesel antiwear agent composition comprising at least a cyclic dicarboxylic acid monoester compound selected from formula 1:

wherein n is an integer of 1 to 8, m is an integer of 0 to 3, x is an integer of 0 to 8, y1 and y2 are integers of 0 to 2, and R is a hydrocarbon group of C1 to C30.

2. The antiwear agent composition according to claim 1, wherein n is an integer of 1 to 6, m is an integer of 0 to 1, x is an integer of 0 to 6, y1 and y2 are integers of 0 to 2, and R is a hydrocarbon group of C1 to C18.

3. The antiwear agent composition according to claim 1 or 2, wherein R is selected from C1-C18 chain aliphatic hydrocarbon groups, C4-C18 cyclic aliphatic hydrocarbon groups, and C7-C18 aryl-substituted hydrocarbon groups or alkyl-substituted aryl groups.

4. The antiwear agent composition according to claim 1, wherein said cyclic dicarboxylic acid monoester compound is selected from the group consisting of 1, 2-cyclopentanedicarboxylic acid monoester, 1, 2-cyclohexanedicarboxylic acid monoester, tetrahydrophthalic acid monoester, phthalic acid monoester, methylhexahydrophthalic acid monoester, methyltetrahydrophthalic acid monoester, 1-methyl-1, 2-cyclohexanedicarboxylic acid monoester, 4-methyl-1, 2-cyclohexanedicarboxylic acid monoester, 3-methyl-1, 2-cyclohexanedicarboxylic acid monoester, 4-methyl-4-cyclohexene-1, 2-dicarboxylic acid monoester, and 3-methyl-4-cyclohexene-1, 2-dicarboxylic acid monoester.

5. The antiwear agent composition according to claim 1, wherein the cyclic dicarboxylic acid monoester compound is 1, 2-cyclohexanedicarboxylic acid monoester, tetrahydrophthalic acid monoester, phthalic acid monoester, methylhexahydrophthalic acid monoester, methyltetrahydrophthalic acid monoester.

6. The antiwear agent is prepared by reacting C5-C18 cyclic dicarboxylic acid or anhydride with C1-C30 alcohol or phenol.

7. The method of claim 6, comprising: C5-C18 cyclic dicarboxylic acid or anhydride and C1-C30 alcohol or phenol react according to the molar ratio of 1: 0.5-1.5, and the reaction temperature is 50-250 ℃.

8. The production process according to claim 6 or 7, wherein the cyclic dicarboxylic acid or anhydride is selected from the group consisting of 1, 2-cyclohexanedicarboxylic acid, phthalic acid, tetrahydrophthalic acid, methyltetrahydrophthalic acid, methylhexahydrophthalic acid, 1, 2-cyclohexanedicarboxylic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride.

9. The process according to claim 6 or 7, wherein the alcohol or phenol is selected from the group consisting of C1-C18 aliphatic alcohols, C4-C18 alicyclic alcohols, and C7-C18 aromatic alcohols or phenols.

10. The production process according to claim 6 or 7, wherein the alcohol or phenol is selected from the group consisting of methanol, ethanol, propanol, n-butanol, sec-butanol, cyclohexanol, 3-cyclohexene-1-methanol, benzyl alcohol, isooctanol, isononyl alcohol, decyl alcohol, isodecyl alcohol, lauryl alcohol, oleyl alcohol, nonyl phenol, and isomeric nonyl alcohols, isomeric undecyl alcohols, and isomeric tridecyl alcohols obtained by polymerizing ethylene, propylene or butene.

11. The process according to claim 6 or 7, wherein the reaction is carried out in the absence of a catalyst or a solvent, and the C5-C12 cyclic acid anhydride and the C1-C18 alcohol or phenol are reacted at a molar ratio of 1: 0.8-1.3 at a temperature of 60-180 ℃ for 0.5-10 hr.

12. The process according to claim 6 or 7, wherein the reaction is carried out in the presence of a catalyst and in the presence or absence of a solvent, the molar ratio of the C5-C12 cyclic dicarboxylic acid to the C1-C18 alcohol or phenol is 1: 0.8-1.3, the reaction temperature is 70-250 ℃, and the reaction time is 3-15 hr.

13. A method for improving the lubricity of diesel oil, which comprises adding the cyclic dicarboxylic acid monoester compound according to any one of claims 1 to 5 to low-sulfur diesel oil in an amount of 10 to 400ppm based on 100% by mass of the diesel oil.

14. A diesel oil composition comprising a low-sulfur diesel oil and the cyclic dicarboxylic acid monoester compound according to any one of claims 1 to 5, wherein the content of the cyclic dicarboxylic acid monoester compound is 10 to 400ppm, based on 100% by mass of the diesel oil.

Technical Field

The invention relates to the field of fuels, in particular to an ester diesel antiwear agent and a preparation method and application thereof.

Background

Sulfur and polycyclic aromatic hydrocarbon are the most harmful elements for increasing the content of pollutants in the atmosphere, especially the content of particle pollutants, with the increasing attention of the world to the environmental problems, the modern oil refining industry takes the clean fuel for producing low-sulfur low aromatic hydrocarbon as the development direction of the modern oil refining industry, under the condition, the production standard of diesel oil is gradually improved, the European Union has used the diesel oil with the sulfur content not more than 10mg/kg and the polycyclic aromatic hydrocarbon mass fraction not more than 8 percent in the European low-sulfur stage emission standard, China has also implemented the national standard GB19147-2016 (VI) for meeting the national standard of diesel oil emitted by the Liu nationality, the sulfur content is not more than 10mg/kg, and the polycyclic aromatic hydrocarbon mass fraction is not more than 7 percent. The clean diesel oil has the characteristics of low aromatic hydrocarbon content, high cetane number, light fraction, low sulfur and low nitrogen, so that the lubricating property of the diesel oil is obviously reduced, and a fuel pump is easy to wear and lose efficacy.

Because low sulfur diesel oil has poor lubricity, low sulfur diesel oil and ultra low sulfur diesel oil are generally treated with a lubricity additive (anti-wear agent) to improve the lubricity thereof. The method has the advantages of low cost, flexible production, less pollution and the like, and is widely regarded in industry.

Most diesel antiwear agents are derivatives of fatty acids, fatty acid esters, amides, or salts. EP773279 discloses carboxylic acid esters prepared by reacting dimer acid with alcohol amine as diesel antiwear agents. EP798364 discloses salts or amides prepared by reacting fatty acids with fatty amines as diesel antiwear agents. EP1209217 discloses the reaction products of C6-C50 saturated fatty acids and dicarboxylic acids with short chain oil-soluble primary, secondary and tertiary amines as diesel antiwear agents. WO9915607 discloses the reaction product of a dimerised fatty acid with an epoxide as a diesel antiwear agent. Most of the technologies react fatty acid or fatty acid dimer with alcohol amine, amine and epoxide, wherein some reaction raw materials have higher cost and common anti-wear effect, and the addition amount of the reaction raw materials in diesel oil is larger.

The existing industrial low-sulfur diesel oil antiwear agent mainly comprises two types of acid type and ester type, wherein the main component of the acid type antiwear agent is long-chain unsaturated fatty acid such as oleic acid, linoleic acid, linolenic acid and the like, and a typical product is refined tall oil fatty acid. The ester-type antiwear agent is an esterification reaction product of the above fatty acid with a polyhydric alcohol. WO9417160a1 discloses the use of monoglycerides of oleic acid as lubricity additives for diesel fuels.

The fatty acid type antiwear agent is used for solving the problems of diesel oil lubricity, namely the cost is relatively low, but the problems of excessive diesel oil acidity, increased corrosivity risk and the like are caused by large dosage along with the upgrading of diesel oil emission standard and the deterioration of lubricity. Although the dosage of the fatty acid ester type antiwear agent is small, the cost is high, and the additive diesel oil is in danger of emulsification and turbidity when meeting water.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides a diesel antiwear agent with a simple structure, a preparation method thereof and a diesel composition containing the antiwear agent. The diesel oil antiwear agent provided by the invention has excellent effect, is less in dosage in diesel oil, and can greatly reduce the risk of the diesel oil becoming turbid in emulsification in the use of the diesel oil antiwear agent.

The inventor of the application unexpectedly finds that the lubricity of the diesel can be greatly improved by adding a small amount of the cyclic dicarboxylic acid monoester compound into the low-sulfur diesel, and the effect of the cyclic dicarboxylic acid monoester compound is much better than that of the fatty acid type or fatty acid glyceride type antiwear agent commonly used in the industry at present.

In order to achieve the above object, in a first aspect, the present invention provides a diesel antiwear agent composition containing at least a cyclic dicarboxylic acid monoester compound selected from formula 1:

wherein n is an integer of 1 to 8, m is an integer of 0 to 3, x is an integer of 0 to 8, y1, y2 are integers of 0 to 2, and R is a hydrocarbon group of C1 to C30. Preferably, n is an integer of 1 to 6, m is an integer of 0 to 1, x is an integer of 0 to 6, y1, y2 are integers of 0 to 2, and R is a hydrocarbon group of C1 to C18.

When n is 1, x is 0, y1, y2 is 1, and m is 0, the monoester compound of formula 1 is 1, 2-cyclopropanedicarboxylic acid monoester.

When n is 1, x is 0, y1, y2 is 1, and m is 1, the monoester compound of formula 1 is 1, 2-cyclopropanediacetic acid monoester.

When n is 1, x is 2, y1, y2 is 2, and m is 0, the monoester compound of formula 1 is 1, 1-cyclopropanedicarboxylic monoester.

When n is 2, x is 0, y1, y2 is 1, and m is 0, the monoester compound of formula 1 is 1, 2-cyclobutane dicarboxylic acid monoester.

When n is 2, x is 0, y1, y2 is 1, and m is 1, the monoester compound of formula 1 is 1, 2-cyclobutanediacetic acid monoester.

When n is 3, x is 0, y1, y2 is 1, and m is 0, the monoester compound of formula 1 is 1, 2-cyclopentanedicarboxylic acid monoester.

When n is 3, x is 0, y1, y2 is 1 and m is 1, the monoester compound of formula 1 is 1, 2-cyclopentanediacetic acid monoester

When n is 3, x is 1, y1, y2 is 1 and the other is 2, and m is 0, the monoester compound of formula 1 is 1, 3-cyclopentanedicarboxylic acid monoester.

When n is 4, x is 0, y1, y2 is 1, and m is 0, the monoester compound of formula 1 is a1, 2-cyclohexanedicarboxylic acid monoester.

When n is 4, x is 0, y1, y2 is 1, and m is 1, the monoester compound of formula 1 is 1, 2-cyclohexanediacetic acid monoester.

When n is 4, x is 1, y1, y2 is 1 and the other is 2, and m is 0, the monoester compound of formula 1 is 1, 3-cyclohexanedicarboxylic acid monoester.

When n is 4, x is 2, y1, y2 is 2, and m is 0, the monoester compound of formula 1 is a1, 4-cyclohexanedicarboxylic acid monoester.

When n is 4, x is 2, y1, y2 is 1, and m is 0, the monoester compound of formula 1 is 4-cyclohexene-1, 2-dicarboxylic acid monoester (tetrahydrophthalic acid monoester).

When n is 4, x is 2, y1, y2 is 1, and m is 1, the monoester compound of formula 1 is 4-cyclohexene-1, 2-diacetic acid monoester.

When n is 4, x is 4, y1, y2 is 0, and m is 0, the monoester compound of formula 1 is a phthalic monoester.

When n is 4, x is 4, y1, y2 is 0, and m is 1, the monoester compound of formula 1 is an o-phenylenediacetic acid monoester.

When n is 4, x is 5, y1, y2 are 0 one and 1 other, and m is 0, the monoester compound of formula 1 is an isophthalic acid monoester.

When n is 4, x is 6, y1, y2 is 1, and m is 0, the monoester compound of formula 1 is a terephthalic acid monoester.

When n is 5, x is 0, y1, y2 is 1, and m is 0, the monoester compound of formula 1 is 3-methyl-1, 2-cyclohexanedicarboxylic acid monoester (3-methylhexahydrophthalic acid monoester), 4-methyl-1, 2-cyclohexanedicarboxylic acid monoester (4-methylhexahydrophthalic acid monoester), or the like.

When n is 5, x is 2, y1, y2 is 1, and m is 0, the monoester compound of formula 1 is methyl tetrahydrophthalic acid monoester, 4-methyl-4-cyclohexene-1, 2-dicarboxylic acid monoester, 3-methyl-4-cyclohexene-1, 2-dicarboxylic acid monoester, or the like.

The cyclic dicarboxylic acid monoester compound is preferably 1, 2-cyclopentanedicarboxylic acid monoester, 1, 2-cyclohexanedicarboxylic acid monoester, tetrahydrophthalic acid monoester, phthalic acid monoester, methylhexahydrophthalic acid monoester, methyltetrahydrophthalic acid monoester, 1-methyl-1, 2-cyclohexanedicarboxylic acid monoester, 4-methyl-1, 2-cyclohexanedicarboxylic acid monoester, 3-methyl-1, 2-cyclohexanedicarboxylic acid monoester, 4-methyl-4-cyclohexene-1, 2-dicarboxylic acid monoester, 3-methyl-4-cyclohexene-1, 2-dicarboxylic acid monoester, or the like.

Wherein R in the structural formula 1 can be aliphatic hydrocarbon, alicyclic hydrocarbon or aromatic hydrocarbon. The aliphatic hydrocarbon may be linear or branched; can be saturated aliphatic hydrocarbon or unsaturated aliphatic hydrocarbon; the unsaturated aliphatic hydrocarbon may be an aliphatic hydrocarbon containing at least one carbon-carbon double bond (ethylenic bond) or at least one carbon-carbon triple bond (acetylenic bond). The alicyclic hydrocarbon may be a saturated alicyclic hydrocarbon (cycloalkane), or may be an unsaturated alicyclic hydrocarbon. The aromatic hydrocarbon may be monocyclic aromatic hydrocarbon, or may be bicyclic or polycyclic aromatic hydrocarbon. Alicyclic and aromatic hydrocarbons may have various substituents on their rings.

Preferably, R is selected from C1-C18 chain aliphatic radical, C4-C18 cyclic aliphatic radical, and C7-C18 aryl substituted alkyl or alkyl substituted aryl.

When R is a saturated chain aliphatic group, R may be a normal alkyl group or an isomeric alkyl group. When R is an n-alkyl group, a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, an n-nonyl group, an n-decyl group, an n-undecyl group, a mono-n-dodecyl group (lauryl ester group), an n-tetradecyl group, an n-hexadecyl group, an n-octadecyl group and the like are preferable.

When R is an isomeric alkyl group, preferred are an isopropyl group, an isobutyl group, a sec-butyl group, an isopentyl group, an isohexyl group, an isoheptyl group, an isooctyl group (particularly a 2-ethylhexyl group), an isononyl group, an isodecyl group, an isoundecyl group, an isotridecyl group, an isopentadecyl group, an isoheptadecyl group and the like.

When R is an unsaturated chain aliphatic group, preferred are allyl, 2-butenyl, 3-butenyl, isopentenyl, 3-hexenyl, 2-octenyl, 3-nonenyl, 2-decenyl, 7-dodecenyl, 1, 5-hexadienyl, 2, 4-nonadienyl, 2, 4-decadienyl, 9, 11-dodecadienyl and 9-octadecenyl.

When R is a cyclic aliphatic group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a 3-cyclohexenyl group, a 2-cyclohexenyl group and the like are preferable. R may also be a substituted aryl group such as phenyl, methylphenyl, p-nonylphenyl, p-dodecylphenyl and the like. R may also be an aliphatic hydrocarbon group having an aromatic ring, such as benzyl (phenylmethyl), phenylethyl, etc.

The most preferable cyclic dicarboxylic acid monoester compounds are 1, 2-cyclohexanedicarboxylic acid monoester, tetrahydrophthalic acid monoester, phthalic acid monoester, methylhexahydrophthalic acid monoester, and methyltetrahydrophthalic acid monoester.

The diesel antiwear agent composition of the invention can contain a proper amount of diesel and/or organic solvent, a small amount of unreacted raw materials, and some reaction byproducts such as diester compounds are also inevitably contained.

In a second aspect, the invention provides a preparation method of a diesel antiwear agent, wherein the antiwear agent is prepared by reacting C5-C18 cyclic dicarboxylic acid or anhydride with C1-C30 alcohol or phenol.

The reaction conditions include: the molar ratio of the C5-C18 cyclic dicarboxylic acid or anhydride to the C1-C30 alcohol or phenol is 1: 0.5-1.5, the reaction temperature is 50-250 ℃, and the reaction time is 0.1-10 hr;

the cyclic dicarboxylic acid is preferably 1, 2-cyclopentanedicarboxylic acid, 1, 3-cyclopentanedicarboxylic acid, 1, 2-cyclohexanedicarboxylic acid, 1, 2-cyclohexanediacetic acid, phthalic acid, tetrahydrophthalic acid, methyltetrahydrophthalic acid, 4-cyclohexene-1, 2-dicarboxylic acid, methylhexahydrophthalic acid, 1-methyl-1, 2-cyclohexanedicarboxylic acid, 4-methyl-4-cyclohexene-1, 2-dicarboxylic acid, 3-methyl-4-cyclohexene-1, 2-dicarboxylic acid, or the like.

The cyclic acid anhydride is preferably 1, 2-cyclopropane dicarboxylic anhydride (CAS 5617-74-3), 1, 2-cyclopentanedicarboxylic anhydride (CAS 5763-49-5), 1, 3-cyclopentanedicarboxylic anhydride (CAS 6054-16-6), phthalic anhydride (85-44-9), 1, 2-cyclohexanedicarboxylic anhydride (CAS 85-42-7), hexahydrophthalic anhydride (CAS 13149-00-3), 1-cyclohexanediacetic anhydride (CAS 1010-26-0), tetrahydrophthalic anhydride (CAS 2426-02-0), tetrahydrophthalic anhydride (CAS 26266-63-7), tetrahydrophthalic anhydride (CAS 935-79-5), tetrahydrophthalic anhydride (CAS 13149-03-6), Tetrahydrophthalic anhydride (CAS 85-43-8), methyltetrahydrophthalic anhydride (CAS 19428-64-3), methyltetrahydrophthalic anhydride (CAS 5333-84-6), methyltetrahydrophthalic anhydride (CAS 3425-89-6), methyltetrahydrophthalic anhydride (CAS 11070-44-3), methyltetrahydrophthalic anhydride (CAS 26590-20-5), 1-methyl-1, 2-cyclohexanedicarboxylic anhydride (CAS 25550-51-0), 3-methyl-1, 2-cyclohexanedicarboxylic anhydride (CAS 57110-29-9), 4-methyl-1, 2-cyclohexanedicarboxylic anhydride (CAS 19438-60-9), methylhexahydrophthalic anhydride (CAS 34090-76-1), and the like, and mixtures thereof.

The most preferred cyclic dicarboxylic acids or anhydrides are 1, 2-cyclohexanedicarboxylic acid, phthalic acid, tetrahydrophthalic acid, methyltetrahydrophthalic acid, methylhexahydrophthalic acid (methyl-1, 2-cyclohexanedicarboxylic acid), 1, 2-cyclohexanedicarboxylic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride (methyl-1, 2-cyclohexanedicarboxylic anhydride), and the like.

The alcohol or phenol can be aliphatic alcohol, alicyclic alcohol, aromatic alcohol or phenol, and has carbon number of C1-C30, preferably C4-C18. When the alcohol is fatty alcohol, the carbon number is C1-C30, preferably C1-C18; when the alcohol is alicyclic alcohol, the carbon number is C3-C30, preferably C4-C18; when the aromatic alcohol or phenol is used, the carbon number is C6-C30, preferably C7-C18.

The alcohol is preferably a monohydric alcohol. Can be primary alcohol, secondary alcohol or tertiary alcohol; the chain fatty alcohol includes saturated fatty alcohol and unsaturated enol, and the saturated fatty alcohol can be normal fatty alcohol or isomeric fatty alcohol. The alicyclic alcohol can be saturated alicyclic alcohol or unsaturated alicyclic alcohol with double bonds on the ring, and the alcoholic hydroxyl can be connected on the ring or on the aliphatic chain with the ring.

Among the saturated aliphatic alcohols, n-butanol, sec-butanol, n-pentanol, various isomeric pentanols, n-hexanol, various isomeric hexanols, n-heptanol, various isomeric heptanols, n-octanol, various isomeric octanols, n-nonanol, various isomeric nonanols, n-decanol, various isomeric decanols, various isomeric undecanols, lauryl alcohol, n-tridecanol, various isomeric tridecanol, n-tetradecanol, n-cetyl alcohol, n-stearyl alcohol, and the like are preferable.

Among them, the unsaturated fatty alcohol is preferably 2-buten-1-ol, 3-buten-1-ol, isopentenol, 3-hexen-1-ol, 1-hepten-3-ol, methylheptenol, 2-octen-1-ol, 3-nonen-1-ol, 2-decen-1-ol, 7-dodecen-1-ol, 1, 5-hexadienol, 2, 4-nonadien-1-ol, 2, 4-decadien-1-ol, 9, 11-dodecadienol, oleyl alcohol or the like.

Wherein the alicyclic alcohol is preferably cyclobutanol, cyclopentanol, cyclohexanol, 3-cyclopenten-1-ol, 2-cyclohexenol, 3-cyclohexene-1-methanol, etc.

Among them, the aromatic alcohol is preferably benzyl alcohol (benzyl alcohol), phenethyl alcohol, phenylpropyl alcohol, phenylbutanol, 8-phenyl-1-octanol, 1-phenyl-1-propanol, 1-phenyl-1-butanol, 1-phenyl-1-octanol, or the like.

Among them, preferred are propylphenol, butylphenol, pentylphenol, heptylphenol, octylphenol, nonylphenol, decylphenol, dodecylphenol and the like, and particularly preferred are p-nonylphenol and p-dodecylphenol.

The most preferred alcohols or phenols include methanol, ethanol, propanol, n-butanol, sec-butanol, cyclohexanol, 3-cyclohexene-1-methanol, benzyl alcohol, isooctanol, isononanol, decanol, isodecanol, lauryl alcohol, oleyl alcohol, nonyl phenol, and isomeric alcohols of various structures obtained by polymerizing ethylene, propylene or butene, such as isomeric nonanols, isomeric undecanols, isomeric tridecanols, and the like.

The catalyst may or may not be added during the reaction, and the catalyst may be one or more of acid catalyst, such as sulfuric acid, hydrochloric acid, p-toluenesulfonic acid, phosphoric acid, boric acid, acidic ion exchange resin, etc.; ionic liquid catalysts such as 1-butylpyridine/AlCl 4 ionic liquid, and the like; can be catalyzed by inorganic salt solid phaseAgents such as one or more of FeCl3, AlCl3, and the like; molecular sieve catalysts such as one or more of ZSM-5, HZSM-5, Al-MCM-41, etc.; heteropolyacid catalysts such as one or more of PW12/MCM-41, SiW12/MCM-41 and the like; solid super acidic catalysts, such as SO4, may be used^2-/ZrO₂-TiO₂Etc.; alkali catalysts such as NaOH, KOH, sodium methoxide, solid superbase, NaH, etc. may be used. The solvent may or may not be added during the reaction, and the solvent may be hydrocarbon such as alkane and aromatic hydrocarbon, such as petroleum ether, gasoline, toluene, xylene, etc.

The preferable method is to use cyclic anhydride and alcohol or phenol to react under the conditions of no catalyst and no solvent, and the preferable reaction conditions are that the molar ratio of C5-C12 cyclic anhydride to C1-C18 alcohol or phenol is 1: 0.8-1.3, the reaction temperature is 60-180 ℃, and the reaction time is 0.5-10 hr.

Another preferred method is to react the cyclic dicarboxylic acid with C1-C18 alcohol or phenol in the presence of a catalyst and with or without a solvent to obtain the cyclic dicarboxylic acid monoester compound. The preferable reaction conditions are that the molar ratio of the C5-C12 cyclic dicarboxylic acid to the C1-C18 alcohol or phenol is 1: 0.8-1.3, the reaction temperature is 70-250 ℃, and the reaction time is 3-15 hr.

The other method is that C5-C12 cyclic dicarboxylic acid or anhydride and sufficient or excessive C1-C18 alcohol or phenol are used to generate cyclic dicarboxylic acid diester compound, and the cyclic dicarboxylic acid diester compound reacts with cyclic dicarboxylic acid or anhydride in the presence or absence of catalyst to obtain cyclic dicarboxylic acid monoester compound. The preferable reaction condition is that the molar ratio of the diester to the diacid or the anhydride is 1: 0.8-1.3, the reaction temperature is 80-200 ℃, and the reaction time is 3-15 hr.

After the reaction is finished, the product after the catalyst is removed by filtration can be used as the diesel antiwear agent composition, and the product can also be separated and purified according to the standard requirements of the antiwear agent product, for example, the solvent and unreacted raw materials are removed, the solvent and the unreacted raw materials which meet the standard requirements do not influence the performance of the antiwear agent composition, and after the components are added into diesel, the diesel performance is not influenced.

According to the invention, a proper amount of diesel oil can be added into the reaction product to obtain the diesel oil antiwear agent concentrate.

In a third aspect, the invention provides a method for improving the lubricity of diesel oil, which comprises adding the cyclic dicarboxylic acid monoester compound into low-sulfur diesel oil in an amount of 10-400 ppm, preferably 50-300 ppm, based on 100% of the mass of the diesel oil.

In a fourth aspect, the invention provides a diesel oil composition, which comprises low-sulfur diesel oil and the cyclic dicarboxylic acid monoester compound, wherein the content of the cyclic dicarboxylic acid monoester compound is 10-400 ppm, preferably 50-300 ppm, based on 100% of the mass of the diesel oil.

The diesel fuel of the present invention includes various low sulfur diesel fuels. For example, the fuel can be a fuel for a compression ignition type internal combustion engine, which meets the national standard GB/T19147 for automotive diesel oil and is prepared by processing crude oil (petroleum) by various refining processes of an oil refinery, such as atmospheric and vacuum distillation, catalytic cracking, catalytic reforming, coking, hydrofining, hydrocracking and the like to obtain fractions with the distillation range of 160-380 ℃. It may also be a second generation biodiesel, derived from renewable resources such as vegetable oils and animal fats, and which is typically hydrogenated in refineries using hydrotreating processes to hydrogenate vegetable oils to produce isomerized or non-isomerized long chain hydrocarbons by hydrogenation, which may be similar in nature and quality to petroleum-based fuel oils. The diesel oil can be third-generation biodiesel, and the third-generation biodiesel is obtained by processing non-greasy biomass with high cellulose content, such as sawdust, crop straws, solid waste and the like, and microbial oil by gasification and a Fischer-Tropsch technology. The diesel fuel may also be coal-to-liquid diesel fuel (CTL), which refers to diesel fuel obtained by fischer-tropsch synthesis of coal, or diesel fuel obtained by direct liquefaction of coal. Or a mixed diesel oil obtained by adding an oxygen-containing diesel oil blending component into petroleum-based diesel oil, wherein the oxygen-containing diesel oil blending component refers to an oxygen-containing compound or a mixture of oxygen-containing compounds which can be blended with various diesel fuel to meet certain specification requirements, and is usually alcohols, ethers or a mixture thereof.

The diesel oil composition of the present invention may further contain other additives, such as one or more of a phenol-type antioxidant, a polymeric amine-type ashless dispersant, a flow improver, a cetane number improver, a metal deactivator, an antistatic agent, a preservative, a rust inhibitor, and a demulsifier, as required.

The high molecular amine type ashless dispersant comprises one or more of alkenyl succinimide and/or alkenyl succinic acid amide, Mannich base type ashless dispersant, polyether amine type ashless dispersant and polyolefin amine type ashless dispersant. The flow improver is preferably a homopolymer of (meth) acrylate, and/or a polymer of ethylene and vinyl acetate. The cetane improver can be a nitrate or peroxide, such as isooctyl nitrate, di-t-butyl peroxide, and the like. The metal passivator can be one or more of ammonium salt formed by benzotriazole and fatty amine, a product obtained by Mannich reaction of benzotriazole, formaldehyde and fatty amine, Schiff base and organic polycarboxylic acid.

The diesel oil antiwear agent has the advantages of easily obtained raw materials, simple and convenient production, and unexpectedly superior effect to the traditional fatty acid type or fatty acid ester type antiwear agent, can obviously improve the lubricity of low-sulfur diesel oil, greatly reduces the addition amount, and further reduces the use cost.

Detailed Description

Exemplary embodiments that embody features and advantages of the invention are described in detail below in the specification. It is to be understood that the invention is capable of various modifications in various embodiments, all without departing from the scope of the invention.

The present invention will be described in detail below by way of examples. In the following examples, the lubricity of diesel fuel was measured in a High-Frequency Reciprocating Rig (HFRR, PCS instruments, UK) according to SH/T0765 method for the Wear Scar Diameter (Wear Scar Diameter, WSD) at 60 ℃ and the reported result WS1.4 was obtained by correcting the influence of temperature and humidity.

The cyclic dicarboxylic acid monoester compound of the present invention can be synthesized by the above-mentioned method, or can be obtained by purchasing existing industrial products.

Examples 1 to 4 are provided to illustrate the preparation of the cyclic dicarboxylic acid monoester compound according to the present invention.

Example 1

In a 2000mL reactor equipped with an electric stirrer, a thermometer and a reflux condenser, 770g of 1, 2-cyclohexanedicarboxylic anhydride (hexahydrophthalic anhydride, produced by Taiwan south Asia (Taiwan plastic) Co., Ltd.) and 715g of isooctanol (2-ethylhexanol, produced by Zilustone division, China petrochemical Co., Ltd.) were added in a molar ratio of succinic anhydride to isooctanol of about 1:1.1, and the mixture was heated under stirring to 115 ℃ to react for 3 hours, then heated and distilled under reduced pressure to remove unreacted isooctanol, thereby obtaining 1402g of 1, 2-cyclohexanedicarboxylic acid monoisooctyl ester.

Example 2

Into a 500mL reactor equipped with an electric stirrer, a thermometer and a reflux condenser were charged 152g of tetrahydrophthalic anhydride (tetrahydrophthalic anhydride, 99% by mass, produced by Henan Puyang chemical Co., Ltd.) and 172.8g of isomeric nonanol (Exxal)^TM9s, 99.5% by mass, produced by Exxon-Mobil) tetrahydrophthalic anhydride and isomeric nonanols in a molar ratio of about 1:1.2, heating with stirring and warming, reacting at 120 ℃ for 5 hours, then warming and distilling under reduced pressure to remove unreacted isononyl alcohol, to give about 306g of monoisononyl tetrahydrophthalate.

Example 3

336g of methyl-1, 2-cyclohexanedicarboxylic anhydride (methyl hexahydrophthalic anhydride, 99% by mass, produced by Kyoho chemical Co., Ltd., Guangzhou, Kyoho chemical Co., Ltd.) and 440g of nonylphenol (99.5% by mass, produced by Taiwan Chinen chemical Co., Ltd.) were placed in a 1000mL reactor equipped with an electric stirrer, a thermometer and a reflux condenser, the molar ratio of methyl-1, 2-cyclohexanedicarboxylic anhydride to nonylphenol was about 1:1, and the mixture was heated and stirred to 100 ℃ to react for 4.5 hours to obtain about 770g of a product mainly comprising methyl-1, 2-cyclohexanedicarboxylic acid mono-p-nonylphenyl ester.

Example 4

166g of methyltetrahydrophthalic anhydride (98% by mass, produced by Shandong Cheng chemical Co., Ltd.) and 540g of benzyl alcohol (99.5% by mass, produced by Shandong Luxi group Co., Ltd.) were charged into a 500mL reactor equipped with an electric stirrer and a thermometer, the molar ratio of methyltetrahydrophthalic anhydride to benzyl alcohol was about 1:1, the mixture was heated and stirred to 110 ℃ to react for 5.5 hours, and then the temperature was raised and the unreacted benzyl alcohol and methyltetrahydrophthalic anhydride were distilled off under reduced pressure to obtain 996g of monomethyltetrahydrophthalic anhydride.

Example 5 is a commercially available mono butyl phthalate with a purity of 98%.

Example 6 is a commercially available mono (2-ethylhexyl) phthalate (CAS 4376-20-9) with a purity of 97%.

Comparative example

Comparative example 1 is a commercially available diisooctyl hexahydrophthalate (CAS 84-71-9) with a purity of 97%.

Comparative example 2 is a commercially available di (2-ethylhexyl) phthalate (CAS 117-81-7) with a purity of 97%.

Comparative example 3 is a fatty acid type antiwear agent commonly used in the industry-an antiwear agent available from Afton under the designation HiTEC 4140.

Comparative example 4 is an ester type antiwear agent of the fatty acid ester type commonly used in industry-available under the trade designation infinium R655 to the united states of america.

Test example 1

The test example is the use effect of the diesel anti-wear agents of the examples and the comparative examples in diesel oil (the anti-wear agents are respectively mixed with petroleum-based diesel oil a and diesel oil b, the diesel oil a is from middle petrochemical Yanshan division, the diesel oil b is from middle petrochemical high bridge division, and the physical and chemical properties of the diesel oil a and the diesel oil b are shown in table 1). The HFRR method (ISO12156-1) wear scar diameter WS1.4 of the diesel before and after addition is shown in tables 2 and 3. Wherein, the smaller the diameter of the grinding crack, the better the lubricating property of the diesel oil. At present, most of diesel oil standards in the world, such as European standard EN 590, China automotive diesel oil standard GB19147 and automotive diesel oil Beijing city local standard DB 11/239, use the grinding crack diameter less than 460 μm (60 ℃) as the basis for qualified diesel oil lubricity.

TABLE 1

TABLE 2

TABLE 3

As can be seen from tables 2 and 3, the alcohol compounds and the phenol compounds have little antiwear effect and do not improve the lubricity of diesel oil in diesel oil, but the lubricity of diesel oil is surprisingly greatly improved by adding the monoester compound of the present invention.

For low-sulfur diesel oil shown in table 2, the monoester compound of the present invention can greatly improve the lubricity of diesel oil even at a very small addition amount, for example, examples 1 and 2 can reduce the lubricity wear scar diameter of diesel oil a from 564 micrometers to 266 micrometers and 257 micrometers at an addition amount of 150mg/kg, while the diisooctyl hexahydrophthalate compound shown in comparative example 1 has no effect of improving the lubricity of diesel oil; example 6 was able to reduce the lubricating wear scar diameter of diesel oil a from 564 microns to 275 microns at an addition level of 150mg/kg, while the di (2-ethylhexyl) phthalate compound shown in comparative example 2 had no effect of improving the diesel oil lubricity; even the diesel antiwear agent of the fatty acid type (comparative example 3) or the fatty acid ester type (comparative example 4) which is currently used in the industry can only reduce the wear-scar diameter of the diesel a to 427 micrometers and 394 micrometers at 150 mg/kg. When the dosage is further reduced to 80mg/kg, the monoester compound of the invention can also ensure that the lubricity of the diesel oil a meets the requirement of the diesel oil standard, while the comparative examples 3 and 4 have poor anti-wear effect at the dosage and can not meet the requirement of the diesel oil standard which is not more than 460 microns.

For the ultra low sulfur diesel fuel shown in Table 3, the monoester compounds of the present invention surprisingly improved the lubricity of the diesel fuel at very low addition levels, for example, examples 1 and 2 were able to reduce the lubricity wear patterns of diesel fuel b from 651 microns to 296 microns and 281 microns at 200mg/kg, which was unexpected.

The diisooctyl hexahydrophthalate shown in the comparative example 1 can reduce the lubricating wear-mark diameter of the diesel oil b from 651 microns to 638 microns when the addition amount of the diisooctyl hexahydrophthalate is 200mg/kg, and almost no antiwear effect exists, so that the diester compound is not a good antiwear agent, and the diesel oil antiwear agent of the fatty acid type (comparative example 3) or the fatty acid ester type (comparative example 4) can only reduce the wear-mark diameter of the diesel oil b to 432 microns and 387 microns when the addition amount of the diisooctyl hexahydrophthalate is 200 mg/kg.

When the dosage is further reduced to 120mg/kg or 100mg/kg, the monoester compound of the invention can also ensure that the lubricity of the diesel oil b meets the requirement of the diesel oil standard, while the comparative examples 1,2, 3 and 4 ensure that the wear-resisting effect is poor and cannot meet the requirement of the diesel oil standard which is not more than 460 microns because the wear-resisting effect is reduced to 651 microns, 652 microns, 519 microns and 482 microns respectively when the dosage is 120 mg/kg.

Test example 2

The diesel antiwear agents of the examples and the comparative examples are used in the coal-to-diesel (the antiwear agents are respectively mixed with the coal-to-diesel c, the diesel c is derived from the direct coal liquefaction diesel of China Shenhua coal oil company, and the physical and chemical properties are shown in Table 4). The HFRR method (ISO12156-1) wear scar diameter WS1.4 of the diesel before and after addition is shown in Table 5.

TABLE 4

TABLE 5

The results of the test examples show that the diesel antiwear agent provided by the invention has an unexpectedly better effect than a fatty acid type or fatty acid ester type antiwear agent, and when the diesel antiwear agent is used as a diesel antiwear agent, the lubricity of low-sulfur diesel can be remarkably improved, and the addition amount can be greatly reduced. The antiwear agent has the advantages of easily obtained raw materials and simple and convenient production, is an intermediate product or raw material of a common industrial plasticizer, and can further reduce the use cost of the antiwear agent after being used as the antiwear agent.