CN113462442B

CN113462442B - Diesel antiwear agent composition, preparation method thereof and diesel oil composition

Info

Publication number: CN113462442B
Application number: CN202010238790.2A
Authority: CN
Inventors: 蔺建民; 李妍; 夏鑫; 李宝石; 李航
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: 2020-03-30
Filing date: 2020-03-30
Publication date: 2023-06-09
Anticipated expiration: 2040-03-30
Also published as: CN117050792A; CN113462442A

Abstract

The invention relates to a diesel antiwear agent composition, a preparation method thereof and a diesel composition. The diesel antiwear agent contains C2-C20 saturated dicarboxylic acid monoester compound without substituent, and is produced by monoesterification reaction of saturated dicarboxylic acid or anhydride without substituent and alcohol. The antiwear agent of the invention has unexpectedly better effect than fatty acid type or fatty acid ester type antiwear agent, can obviously improve the lubricity of low-sulfur diesel oil when used as diesel oil antiwear agent, greatly reduces the addition amount and further reduces the use cost.

Description

Diesel antiwear agent composition, preparation method thereof and diesel oil composition

Technical Field

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

Background

With the increasing attention of world countries to environmental problems, the production of high-quality clean energy has become the development direction of the modern oil refining industry, and the production standard of diesel oil is gradually increased. The clean diesel oil has the characteristics of low aromatic hydrocarbon content, high cetane number, light fraction, low sulfur and low nitrogen. Sulfur is the most harmful element that increases the pollutant content in the atmosphere, and thus the sulfur-containing compounds content in diesel fuel needs to be strictly controlled. The clean diesel oil produced at present is mainly produced by adopting a hydrogenation process, and the method reduces the content of the nitrogen-containing compound and the oxygen-containing compound in the diesel oil while removing the sulfur-containing compound in the diesel oil. It is known that the lubricity of diesel fuel is largely dependent on the content of antiwear impurities in the diesel fuel, and that polycyclic aromatic hydrocarbons, oxygen-containing impurities and nitrogen-containing impurities are very effective antiwear agents. The lower nitrogen and oxygen content causes a decrease in the lubricating properties of the diesel itself, resulting in wear and failure of the fuel pump.

Low sulfur diesel and ultra low sulfur diesel are commonly treated with lubricity additives (antiwear agents) to improve their lubricity due to their poor lubricity. The method has the advantages of low cost, flexible production, less pollution and the like, and is widely valued in industry.

The diesel antiwear agent is mainly a derivative of fatty acid, fatty acid ester, amide or salt. EP773279 discloses carboxylic esters prepared by reacting dimer acids with alcohol amines as diesel antiwear agents. EP798364 discloses the use of 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 dimerised fatty acids with epoxides as diesel antiwear agents. Most of the technologies react fatty acid or fatty acid dimer with alcohol amine, amine and epoxide, wherein some of the technologies have higher cost of reaction raw materials and general antiwear effect, and the addition amount of the technology in diesel oil is larger.

The existing low-sulfur diesel antiwear agents used in industry mainly comprise an acid type and an ester type, wherein the main components of the acid type antiwear agents are long-chain unsaturated fatty acids such as oleic acid, linoleic acid, linolenic acid and the like, and typical products are derived from refined tall oil fatty acids. The ester type antiwear agent is the esterification reaction product of the above fatty acid and a polyol. WO9417160A1 discloses the use of oleic acid monoglycerides as a diesel lubricity additive.

The fatty acid type antiwear agent solves the problem of diesel oil lubricity, but the problems of exceeding diesel oil acidity, increasing corrosiveness risk and the like caused by the large consumption of the diesel oil with the upgrading of the diesel oil emission standard and the deterioration of the lubricity are solved. The fatty acid ester type antiwear agent is used in small amount, but has high cost and the additive diesel oil is emulsified and muddy when meeting water.

CN109576021a discloses an improver for improving the lubricity of low-sulfur diesel oil and a preparation method thereof, which is to mix unsaturated dicarboxylic acid ester (maleic diester) and polymerization inhibitor at 150-180 ℃, gradually add tung oil biodiesel, continuously react for a certain time at 200-240 ℃ after the addition, and obtain an improver product through reduced pressure distillation after the reaction. The product needs tung oil biodiesel, the raw materials are rare and unstable, the reaction needs high temperature and is difficult to prepare, and the most critical is that the antiwear effect is very common, and more than 600mg/kg needs to be added.

CN106929112a discloses a method for improving the abrasion resistance of low-sulfur diesel, which uses the esterification reaction product of alkenyl succinic anhydride and monohydric aliphatic alcohol to improve the lubricity of diesel, but the product has high viscosity and has a general effect of improving the lubricity of ultra-low-sulfur diesel (such as diesel for vehicles reaching the national vi emission standard).

CN110536964a discloses alkenyl substituted succinic acid monoesters as additives for improving diesel deposits and their use, but substituted dicarboxylic acid esters have a poor effect as antiwear agents.

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 oil composition containing the antiwear agent. The diesel antiwear agent provided by the invention has excellent effect, and is little in use in diesel oil, so that the use cost of the diesel antiwear agent is greatly reduced.

Long-chain unsaturated fatty acids (monoacids) or long-chain unsaturated fatty acid polyol esters are good diesel antiwear agents and have been used in industry for many years, and it is generally recognized by those skilled in the art that long-chain substituents on carboxylic acid groups in the antiwear agent structure can increase the oil solubility of the antiwear agent on the one hand, and can be aligned by intermolecular forces to form a firm protective film, thereby reducing frictional wear of metal surfaces, and are therefore an indispensable group in the antiwear agent structure. For example, the antiwear agent available from Afton corporation under the brand name HiTEC 4140 is a monocarboxylic acid having a long chain substituent of C16 to C18; the antiwear agent with the brand name Infinium R655 of Runner-Ing company is structured as glyceride of monocarboxylic acid with C16-C18 long-chain substituent.

The inventor of the application surprisingly found that the lubricating property of the diesel oil can be greatly improved by adding a small amount of saturated dicarboxylic acid monoester without substituent groups into low-sulfur diesel oil, and the effect is much better than that of the fatty acid type or fatty glyceride type antiwear agent commonly used in the industry at present.

In order to achieve the above object, the present invention provides a diesel antiwear agent composition, which contains at least a substituent-free C2 to C20 saturated dicarboxylic acid monoester compound represented by structural formula 1:

wherein n is an integer of 0 to 18 and R is a C1-C30 hydrocarbon group. Preferably n is an integer from 1 to 10 and R is a C1-C18 hydrocarbon radical. More preferably n is an integer from 2 to 8, R is a C3-C8 hydrocarbyl group, or a C9-C18 hydrocarbyl group.

The saturated dicarboxylic monoester compound without substituent refers to CH between two carbonyl groups in the structural formula 1 ₂ And (3) a structure without branched substituents on the group.

Specifically, the saturated dicarboxylic acid monoester compound represented by structural formula 1 may be selected from oxalic acid (oxalic acid) monoester, malonic acid monoester, succinic acid (succinic acid) monoester, glutaric acid monoester, adipic acid monoester, pimelic acid monoester, suberic acid monoester, azelaic acid monoester, sebacic acid monoester, undecanedioic acid monoester, dodecanedioic acid monoester, tridecanedioic acid monoester, tetradecanedioic acid monoester, hexadecanedioic acid monoester, octadecanedioic acid monoester, and the like.

Wherein R in the structural formula 1 can be aliphatic hydrocarbon group, alicyclic hydrocarbon group or aromatic hydrocarbon group. The aliphatic hydrocarbon can be straight-chain 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 (olefinic bond) or at least one carbon-carbon triple bond (acetylenic bond). The alicyclic hydrocarbon may be a saturated alicyclic hydrocarbon (cycloalkane) or an unsaturated alicyclic hydrocarbon. The aromatic hydrocarbon may be a monocyclic aromatic hydrocarbon or a bicyclic or polycyclic aromatic hydrocarbon. The alicyclic hydrocarbon and aromatic hydrocarbon may have various substituents on the ring.

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

When R is an isopolyl group, isopropyl, isobutyl, sec-butyl, isopentyl, isohexyl, isoheptyl, isooctyl (especially 2-ethylhexyl), isononyl, isodecyl, isoundecyl, isotridecyl, isopentdecyl, isoheptadecyl, etc. are preferred.

When R is an unsaturated chain aliphatic group, it is preferably allyl, 2-butenyl, 3-butenyl, isopentenyl, 3-hexenyl, 2-octenyl, 3-nonenyl, 2-decenyl, 7-dodecenyl, 1, 5-hexadienyl, 2, 4-nondienyl, 2, 4-decadienyl, 9, 11-dodecenyl or 9-octadecenyl.

When R is a cyclic aliphatic group, cyclobutyl, cyclopentyl, cyclohexyl, 3-cyclohexenyl, 2-cyclohexenyl 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 alicyclic group having an aromatic ring, such as benzyl (benzyl), phenethyl, etc.

The Shan Zhilei type compound of the saturated dicarboxylic acid monoester without substituent groups is preferably succinic acid monoester. Further preferred are mono-n-butyl succinate, mono-sec-butyl succinate, mono-n-hexyl succinate, shan Zhengxin succinate, shan Zhenggui succinate, mono-n-dodecyl succinate (lauryl ester), mono-isobutyl succinate, mono-tert-butyl succinate, mono-isoamyl succinate, mono-isohexyl succinate, mono-isooctyl succinate, mono-isononyl succinate, mono-isodecyl succinate, mono-isoundecyl succinate, mono-isotridecyl succinate, mono-oleyl succinate (mono-9-stearyl succinate), monocyclohexyl succinate, mono-3-cyclohexene-1-methyl succinate, mono-p-nonylphenyl succinate, mono-benzyl succinate, and the like.

The saturated dicarboxylic acid monoester type compounds without substituent groups are also preferably oxalic acid monoester, malonic acid monoester, glutaric acid monoester, adipic acid monoester, azelaic acid monoester and sebacic acid monoester.

In a preferred embodiment of the monoesters of oxalic acid, monomethyl oxalate, monoethyl oxalate, monopropyl oxalate, mono-n-butyl oxalate, monoisobutyl oxalate, mono-t-butyl oxalate, monoisooctyl oxalate, monoisononyl oxalate, monoisodecyl oxalate, monoisoundecyl oxalate, monolauryl oxalate, monoisotridecyl oxalate, monooleyl oxalate (mono-9-stearyl oxalate), monocyclohexyl oxalate, mono-3-cyclohexene-1-methyl oxalate, mono-p-nonylphenyl oxalate, monobenzyl oxalate and the like are further preferred.

In a preferred embodiment of the malonic acid monoester, monomethyl malonate, monoethyl malonate, monopropyl malonate, mono-n-butyl malonate, monoisobutyl malonate, mono-t-butyl malonate, monoisooctyl malonate, monoisononyl malonate, monoisodecyl malonate, monoisoundecyl malonate, monolauryl malonate, monoisotridecyl malonate, monooleyl malonate (mono-9-stearyl enolate), monocyclohexyl malonate, mono-3-cyclohexene-1-methyl malonate, mono-p-nonylphenyl malonate, monobenzyl malonate, and the like are further preferred.

In a preferred embodiment of the mono-glutarate, more preferred are monomethyl glutarate, monoethyl glutarate, monopropyl glutarate, mono-n-butyl glutarate, monoisobutyl glutarate, mono-t-butyl glutarate, monoisooctyl glutarate, monoisononyl glutarate, monoisodecyl glutarate, monoisoundecyl glutarate, monolauryl glutarate, monoisotridecyl glutarate, monooleyl glutarate (mono-9-stearyl glutarate), monocyclohexyl glutarate, mono-3-cyclohexene-1-methyl glutarate, mono-p-nonylphenyl glutarate, monobenzyl glutarate, and the like.

In a preferred embodiment of the monoester adipate, monomethyl adipate, monoethyl adipate, monopropyl adipate, mono-n-butyl adipate, monoisobutyl adipate, monoisooctyl adipate, monoisononyl adipate, monoisodecyl adipate, monoisoundecyl adipate, monolauryl adipate, monoisotridecyl adipate, monooleyl adipate (mono-9-octadecenyl adipate), monocyclohexyl adipate, mono-3-cyclohexene-1-methyl adipate, mono-p-nonylphenyl adipate, monobenzyl adipate, and the like are further preferred.

In a preferred embodiment of the monoesters of azelaic acid, monomethyl azelate, monoethyl azelate, monopropyl azelate, n-butyl azelate, monoisobutyl azelate, monoisooctyl azelate, monoisononyl azelate, monoisodecyl azelate, monoisonicoyl azelate, monolauryl azelate, monoisotridecyl azelate, monol azelate (mono-9-octadecenyl azelate), monocyclohexyl azelate, mono-3-cyclohexene-1-methyl azelate, mono-p-nonylphenyl azelate, monobenzyl azelate, and the like are further preferred.

In a preferred embodiment of the monoesters of sebacic acid, monomethyl sebacate, monoethyl sebacate, monopropyl sebacate, mono-n-butyl sebacate, monoisobutyl sebacate, monoisooctyl sebacate, monoisononyl sebacate, monoisodecyl sebacate, monoisoundecyl sebacate, monolauryl sebacate, monoisotridecyl sebacate, monooleyl sebacate (mono-9-stearyl sebacate), monocyclohexyl sebacate, mono-3-cyclohexene-1-methyl sebacate, mono-p-nonylphenyl sebacate, monobenzyl sebacate, and the like are further preferred.

The diesel antiwear agent composition of the present invention may contain a proper amount of diesel oil and/or an organic solvent, and a small amount of unreacted raw materials, and also inevitably contains some reaction by-products, such as saturated dicarboxylic acid diester compounds.

In a second aspect, the invention provides a method for preparing a diesel antiwear agent, wherein the antiwear agent is prepared by reacting unsubstituted C2-C20 saturated dicarboxylic acid or anhydride with C1-C30 alcohol or phenol.

Specific reaction conditions include: the molar ratio of the C2-C20 saturated dicarboxylic acid or anhydride without substituent groups to the C1-C30 alcohol or phenol is 1:0.5-1.5, the reaction temperature is 50-250 ℃, the reaction time is 0.1-10 hr, and the reaction pressure can be normal pressure or can be carried out under a certain pressure.

The unsubstituted saturated dicarboxylic acid may be selected from oxalic acid (oxalic acid), malonic acid, succinic acid (succinic acid), glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, tridecanedioic acid, tetradecanedioic acid, hexadecanedioic acid, octadecanedioic acid, etc., preferably succinic acid, adipic acid, suberic acid, azelaic acid, sebacic acid, etc. The unsubstituted saturated dianhydride is preferably succinic anhydride (succinic anhydride), glutaric anhydride, adipic anhydride or the like.

The alcohol or phenol may be an aliphatic alcohol, alicyclic alcohol, aromatic alcohol or phenol having a carbon number of C1 to C30, preferably C4 to C18. In the case of fatty alcohols, the carbon number is from C1 to C30, for example from C4 to C8, or from C9 to C18; in the case of alicyclic alcohols, the carbon number is from C3 to C30, preferably from C4 to C18; in the case of aromatic alcohols or phenols, the carbon number is from C6 to C30, preferably from C7 to C18.

The alcohol is preferably a monohydric alcohol. Can be primary or secondary or tertiary alcohols; the chain fatty alcohol includes saturated fatty alcohol and unsaturated enol, and may be normal fatty alcohol or isomeric fatty alcohol. The alicyclic alcohol may be a saturated alicyclic alcohol or an unsaturated alicyclic alcohol having a double bond in the ring, and the alcoholic hydroxyl group may be attached to the ring or to the alicyclic chain having a ring.

Among them, preferred saturated fatty alcohols are n-butanol, sec-butanol, tert-butanol, n-pentanol, iso-pentanol (3-methyl butanol), n-hexanol, n-heptanol, 2-heptanol, n-octanol, 2-octanol (sec-octanol), iso-octanol (2-ethylhexanol), 3, 5-trimethylhexanol (isononanol), 7-methyl-1-octanol (isononanol), n-decanol, 2-propylheptanol (isodecanol), 8-methyl-1-nonanol (isodecanol), iso-undecanol, lauryl alcohol, iso-tridecyl alcohol, n-tetradecanol, n-hexadecanol, n-octadecyl alcohol, and the like.

Among them, 2-buten-1-ol, 3-buten-1-ol, isopentenyl, 3-hexen-1-ol, 1-hepten-3-ol, methylhepten-ol, 2-octen-1-ol, 3-nonen-1-ol, 2-decen-1-ol, 7-dodecen-1-ol, 1, 5-hexadienol, 2, 4-nonen-1-ol, 2, 4-decdien-1-ol, 9, 11-dodecen-dienol, oleyl alcohol and the like are preferable.

Among them, alicyclic alcohols are preferably cyclobutylalcohol, cyclopentanol, cyclohexanol, 3-cyclopenten-1-ol, 2-cyclohexenol, 3-cyclohexene-1-methanol and the like.

Among them, benzyl alcohol (benzyl alcohol), phenethyl alcohol, phenylpropanol, phenylbutanol, phenyloctanol (e.g., 8-phenyl-1-octanol, 1-phenyl-1-octanol) and the like are preferable as the aromatic alcohol.

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

Most preferred alcohols or phenols include n-butanol, sec-butanol, cyclohexanol, 3-cyclohexene-1-methanol, benzyl alcohol, isooctanol, isononanol, decyl alcohol, isodecyl alcohol, lauryl alcohol, oleyl alcohol, nonylphenol, and isomeric alcohols of various structures such as isomeric nonanols, isomeric undecanol, isomeric tridecanols and the like, produced by polymerization of ethylene, propylene or butene.

The catalyst can be added or not during the reaction, and the catalyst can be one or more of acid catalysts such as sulfuric acid, hydrochloric acid, p-toluenesulfonic acid, phosphoric acid, boric acid, acid ion exchange resin and the like; ionic liquid catalysts such as 1-butylpyridine/AlCl 4 ionic liquids and the like can be used; inorganic salt solid phase catalysts such as one or more of FeCl3, alCl3, etc. may be used; molecular sieve catalysts, such as one or more of ZSM-5, HZSM-5, al-MCM-41, and the like, may be used; heteropolyacid catalysts such as one or more of PW12/MCM-41, siW12/MCM-41, etc. may be used; can be prepared with solid superacid catalysts, such as SO ₄ ^2- /ZrO ₂ -TiO ₂ 、SO ₄ ^2- /TiO ₂ -Al ₂ O ₃ Etc.; alkali catalysts such as NaOH, KOH, sodium methoxide, solid super bases, naH, etc. may be used.

The solvent can be added or not added during the reaction, and the solvent can be hydrocarbon such as alkane and aromatic hydrocarbon, for example petroleum ether, gasoline, toluene, xylene and the like.

The preferred method is to react the C3-C12 saturated anhydride without substituent with the C1-C18 alcohol or phenol under the condition of no catalyst and no solvent, the preferred reaction condition is that the mol ratio of the saturated anhydride without substituent to the C1-C18 alcohol or phenol is 1:0.8-1.3, the reaction temperature is 60-100 ℃ and the reaction time is 0.5-5 hr.

In a preferred alternative method, a saturated dicarboxylic acid monoester compound having no substituent is obtained by reacting a saturated dicarboxylic acid having no substituent with an alcohol having 1 to 18 carbon atoms or a phenol in the presence of a catalyst, with or without a solvent. The preferable reaction condition is that the mol ratio of saturated dicarboxylic acid without substituent groups and 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 preferred method is that C3-C12 saturated dicarboxylic acid or anhydride without substituent reacts with sufficient or excessive C1-C18 alcohol or phenol to generate saturated dicarboxylic acid diester compound without substituent, and then the saturated dicarboxylic acid diester compound reacts with saturated dicarboxylic acid or anhydride under the condition of catalyst, presence or absence of solvent to obtain saturated dicarboxylic acid monoester compound. The preferable reaction condition is that the mole ratio of diester to diacid or 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 of the invention, and the product can 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 meeting the standard requirements do not influence the performance of the antiwear agent of the invention, and the components are added into diesel, so that the performance of the diesel is not adversely affected.

According to the invention, a suitable amount of diesel fuel may be added to the reaction product to obtain a diesel antiwear agent concentrate.

In a third aspect, the present invention provides a method for improving the lubricity of diesel fuel, which comprises adding said unsubstituted C2-C20 saturated dicarboxylic acid monoester compound to low sulfur diesel fuel in an amount of 10 to 400ppm, preferably 50 to 300ppm, based on 100% by mass of diesel fuel.

In a fourth aspect, the present invention provides a diesel fuel composition comprising a low sulfur diesel fuel and said unsubstituted C2-C20 saturated dicarboxylic acid monoester compound in an amount of 10 to 400ppm, preferably 50 to 300ppm, based on 100% by mass of the diesel fuel.

The diesel fuel of the present invention includes various low sulfur diesel fuels. For example, the fuel for the compression ignition type internal combustion engine can be prepared by processing crude oil (petroleum) by various refining processes of a refinery such as atmospheric and vacuum pressure, catalytic cracking, catalytic reforming, coking, hydrofining, hydrocracking and the like, and preparing the fraction with the distillation range of 160-380 ℃.

The diesel fuel may also be a second generation biodiesel derived from renewable resources such as vegetable oils and animal fats, and is typically hydrotreated in a refinery, producing 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 treating non-greasy biomass with high cellulose content, such as wood chips, crop straws, solid wastes and the like, and microbial grease by adopting gasification and Fischer-Tropsch technology.

The diesel fuel may also be a coal liquefied diesel (CTL), which refers to a diesel fuel obtained by fischer-tropsch synthesis of coal, or a diesel fuel obtained by direct liquefaction of coal. The diesel fuel can also be mixed diesel fuel obtained by adding an oxygen-containing diesel fuel blending component into petroleum-based diesel fuel, wherein the oxygen-containing diesel fuel blending component refers to oxygen-containing compounds or oxygen-containing compound mixtures which can be blended with various diesel fuels to meet certain specification requirements, and the oxygen-containing diesel fuel blending component is usually alcohols and ethers or the mixture thereof.

The diesel fuel composition of the present invention may further contain other additives such as one or more of a phenolic antioxidant, a polymeric amine type ashless dispersant, a flow improver, a cetane improver, a metal deactivator, an antistatic agent, a preservative, an antirust agent, and a demulsifier, according to the use requirements.

The macromolecular 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 nitrate or peroxide, such as isooctyl nitrate, di-tert-butyl peroxide, and the like. The metal deactivator may be one or more of ammonium salt formed by benzotriazole and fatty amine, product obtained by Mannich reaction of benzotriazole, formaldehyde and fatty amine, schiff base and organic polycarboxylic acid.

The diesel antiwear agent has the advantages of easily available raw materials, simple and convenient production, unexpectedly superior effect to the traditional fatty acid type or fatty acid ester type antiwear agent, remarkably improved lubricity of low-sulfur diesel, greatly reduced addition amount and further reduced use cost.

Detailed Description

Exemplary embodiments that embody features and advantages of the present invention will be described in detail in the following description. It will be appreciated that the invention is capable of numerous modifications in various embodiments without departing from the scope of the invention.

The present invention will be described in detail by examples. In the following examples, the lubricity of diesel fuel was measured according to SH/T0765 method on a High frequency reciprocating tester (High-Frequency Reciprocating Rig, HFRR, british PCS instruments Co.) for wear scar diameter at 60℃ (Wear Scar Diameter, WSD) and the reported result WS1.4 was obtained by correcting for the effects of temperature and humidity.

The saturated diacid monoester compound without substituent groups can be synthesized by the method, and can also be obtained by purchasing the existing industrial products.

Examples 1 to 6 are provided to illustrate the preparation of succinic monoester compounds.

Example 1

490g of succinic anhydride (succinic anhydride, mass fraction: 99% of Shanghai Shen Renjing refining Co., ltd.) and 700g of isooctanol (2-ethylhexanol, mass fraction: 99.9% of Qilu petrochemical Co., ltd.) were charged into a 2000mL reactor equipped with an electric stirrer, a thermometer and a reflux condenser, the molar ratio of succinic anhydride to isooctanol was about 1:1.1, and after heating and stirring to 110℃and reacting for 4 hours, the temperature was raised and unreacted isooctanol was distilled off under reduced pressure to obtain 1109g of monoisooctyl succinate.

Example 2

Into a 3000mL reactor equipped with an electric stirrer, a thermometer, a reflux condenser and a water separator, 500g of succinic acid (succinic acid)99.5% by mass, manufactured by Shanghai Shen Renjing refiner company, inc.), 915g of isomeric nonanols (Exxal) ^TM 9s, mass fraction of 99.5%, produced by Exxon-Mobil company) and 11g of p-toluenesulfonic acid, wherein the molar ratio of succinic acid to isopolynonanol is about 1:1.5, heating, stirring and heating, introducing slightly weak nitrogen, reacting at 140 ℃ for 6 hours, heating and distilling under reduced pressure to remove unreacted isononyl alcohol and succinic acid, and rectifying to obtain 1156g of monoisononyl succinate.

Example 3

Into a 500mL reactor equipped with an electric stirrer, a thermometer and a reflux condenser, 100g of succinic anhydride (succinic anhydride, mass fraction: 99.5%, manufactured by Aba Ding Shiji Co.) and 220g of nonylphenol (mass fraction: 99.5%) were charged, the molar ratio of succinic anhydride to nonylphenol was about 1:1, and the mixture was heated and stirred to 100℃to obtain 313g of mono-p-nonylphenyl succinate as the main product after reacting for 5.5 hours.

Example 4

490g of succinic anhydride (99.5% by mass, TCI reagent Co.) and 540g of benzyl alcohol (benzyl alcohol, 99.5% by mass, manufactured by Shandong Ruxi group Co., ltd.) were charged into a 2000mL reactor equipped with an electric stirrer and a thermometer, and the molar ratio of succinic anhydride to benzyl alcohol was about 1:1, and after heating and stirring to 100℃for 4.5 hours, the temperature was increased and unreacted benzyl alcohol and succinic anhydride were distilled off under reduced pressure to obtain 996g of monobenzyl succinate.

Example 5

147g of succinic anhydride (99.5% by mass, ara Ding Shiji) and 180g of cyclohexanol (98% by mass, ara Ding Shiji) were added to a 500mL reactor equipped with an electric stirrer, a thermometer and a reflux condenser, the molar ratio of succinic anhydride to cyclohexanol was about 1.1:1, and after reaction for 6 hours at 80℃with stirring by heating, unreacted cyclohexanol was distilled off under reduced pressure to give 296g of cyclohexyl succinate.

Example 6

147g of succinic anhydride (mass fraction: 99.5%, aba Ding Shiji) and 152g of 3-cyclohexene-1-methanol (mass fraction: 99.5%, manufactured by TCI reagent Co.) were charged into a 500mL reactor equipped with an electric stirrer, a thermometer and a reflux condenser, and the molar ratio of succinic anhydride to 3-cyclohexene-1-methanol was about 1:0.9, and the mixture was heated, stirred and heated to 90℃to react for 3.5 hours to obtain mono-3-cyclohexene-1-methyl succinate.

Example 7 is a commercially available mono-tert-butyl malonate with a purity of 95%.

Example 8 is commercially available monobutyl succinate, 98% pure.

Example 9 is commercially available monomethyl adipate, 98% pure.

Example 10 is commercially available monoethyl adipate, 98% purity.

Example 11 is commercially available monomethyl azelate, 97% pure.

Example 12 is commercially available monobutyl sebacate, 90% pure.

Example 13

In a 1000mL reactor equipped with an electric stirrer, a thermometer, a reflux condenser and a water separator, 202g of azelaic acid (mass fraction: 98%, manufactured by Aba Ding Shiji company), 230g of isononanol (mass fraction: 99.5%, manufactured by Oldham's petrochemical company) and 1.3g of concentrated sulfuric acid catalyst were added, the molar ratio of azelaic acid to isononanol was about 1:1.6, the catalyst was 0.3% of the total mass of the total reactants, 130g of toluene was added, stirring reflux reaction was carried out at 120℃for 4hr, and 180-210 ℃ (0.533 kpa) fractions were collected by rectification to obtain 226g of monoisononyl azelate.

Comparative example 1

According to the technical scheme of CN106929112A, dodecenyl succinic acid monomethyl ester is prepared.

Comparative example 2

Commercial diisooctyl succinate with a purity of 98%.

Comparative example 3

Fatty acid type antiwear agents commonly used in industry: an antiwear agent available from Afton corporation under the brand name HiTEC 4140.

Comparative example 4

Fatty acid ester type antiwear agents commonly used in industry: ester type antiwear agent with Infinium R655.

Comparative example 5

The succinic anhydride of example 1 was replaced with methyl succinic anhydride to give monoisooctyl methylsuccinate.

Test case

The test example shows the use effect of the unsaturated fatty acid ester diesel antiwear agent prepared in the examples and the comparative examples in diesel (the antiwear agent is respectively mixed with diesel a and diesel b, wherein the diesel a is derived from the middle petrochemical Yanshan division company, the diesel b is derived from the middle petrochemical high-bridge division company, and the physicochemical properties of the diesel a and the diesel b are shown in table 1). The HFRR process (ISO 12156-1) for diesel fuel before and after dosing, the plaque diameter WS1.4, is shown in tables 2 and 3. Among them, the smaller the wear scar diameter is, the better the diesel lubricity is. At present, most of the world diesel standards such as European standard EN 590, chinese vehicle diesel standard GB 19147 and vehicle diesel Beijing local standard DB 11/239 are qualified by taking the grinding mark diameter smaller than 460 mu m (60 ℃) as the basis of qualified diesel lubricity.

TABLE 1

TABLE 2

TABLE 3 Table 3

As can be seen from tables 2 and 3, the alcohol compound has no antiwear effect, and does not improve the lubricity of diesel in diesel, for example, the lubricity of diesel is not substantially improved after isooctanol is added, whereas the lubricity of diesel is surprisingly greatly improved after the substituent-free saturated dicarboxylic acid monoester compound of the present invention is added.

For the low sulfur diesel fuel shown in Table 2, the saturated dicarboxylic acid monoester compound without substituent according to the present invention can also greatly improve the lubricity of diesel fuel at a very small addition amount, for example, examples 1 and 2 can reduce the lubricity plaque diameter of diesel fuel a from 564 micrometers to 254 micrometers and 232 micrometers at an addition amount of 150mg/kg, whereas the dodecenyl succinic acid monoester shown in comparative example 1 is reduced to 389 micrometers, and the succinic acid diester compound shown in comparative example 2 has no effect of improving the lubricity of diesel fuel; even the fatty acid type (comparative example 3) or fatty acid ester type (comparative example 4) diesel antiwear agents currently commonly used in industry can only reduce the plaque diameter of diesel a to 427 and 394 microns at 150mg/kg, the branched substituted saturated dicarboxylic acid monoester, such as monoisooctyl methylsuccinate shown in comparative example 5, has much poorer effect than the unsaturated dicarboxylic acid monoester without branched substitution, such as monoisooctyl succinate, at the same dosage, and the butenedioic acid monoester compound of the present invention has an unparalleled antiwear effect. When the dosage is further reduced to 80mg/kg, the butenedioic acid monoester compound can ensure that the lubricity of the diesel oil a meets the standard requirement of the diesel oil, and the comparative example has poor antiwear effect when the dosage is added, and can not meet the requirement of not more than 460 microns of the standard requirement of the diesel oil.

For the ultra low sulfur diesel fuel shown in Table 3, the unsubstituted saturated dicarboxylic acid monoester compound of the present invention surprisingly improves the lubricity of the diesel fuel at very small addition levels, for example, examples 1 and 2 were able to reduce the lubricity plaque diameter of diesel fuel b from 651 microns to 233 microns and 228 microns at addition levels of 200mg/kg, which is surprising.

The dodecenylsuccinic monoester shown in comparative example 1 was added in an amount of 200mg/kg to reduce the lubricating plaque diameter of diesel oil b from 651 micrometers to 389 micrometers, and the fatty acid type (comparative example 3) or fatty acid ester type (comparative example 4) diesel oil antiwear agent was also capable of reducing the plaque diameter of diesel oil b only to 432 micrometers and 387 micrometers at 200 mg/kg. When the dosage is further reduced to 120mg/kg, the saturated dicarboxylic acid monoester compound without substituent groups can ensure that the lubricity of the diesel oil b meets the standard requirement of the diesel oil, and when the dosage is 120mg/kg, the abrasive spot diameters of the diesel oil b are reduced to 471 micrometers, 519 micrometers and 482 micrometers in comparative examples 1, 2 and 3, the abrasion resistance effect is poor, and the specification of not more than 460 micrometers required by the standard diesel oil cannot be met. As can be seen from comparative example 5, the substituted saturated dicarboxylic acid monoester compound is much less effective than the unsubstituted saturated dicarboxylic acid monoester compound.

From the results of the above test examples, it can be seen that the antiwear agent of the present invention is unexpectedly superior to the fatty acid type or fatty acid ester type antiwear agent in effect, and the use of the antiwear agent as a diesel oil antiwear agent can significantly improve the lubricity of low-sulfur diesel oil, greatly reduce the addition amount, and further reduce the use cost.

Claims

1. The diesel oil composition at least comprises diesel oil and a saturated dicarboxylic acid monoester compound without substituent, wherein the content of the saturated dicarboxylic acid monoester compound without substituent is 10-400 ppm based on the mass of the diesel oil, and the saturated dicarboxylic acid monoester compound without substituent is selected from oxalic acid monoester, malonic acid monoester, glutaric acid monoester, adipic acid monoester, pimelic acid monoester, suberic acid monoester, azelaic acid monoester and sebacic acid monoester, and the ester group contains a C1-C30 alkyl group.

2. The composition according to claim 1, wherein the unsubstituted saturated dicarboxylic acid monoester compound is selected from mono-tert-butyl malonate, monomethyl adipate, monoethyl adipate, monopropyl adipate, monobutyl adipate, monoisooctyl adipate, monoisononyl adipate, monomethyl azelate, monoethyl azelate, monopropyl azelate, monobutyl azelate, monoisooctyl azelate, monoisononyl azelate, monomethyl sebacate, monoethyl sebacate, monopropyl sebacate, monobutyl sebacate, monoisooctyl sebacate, monoisononyl sebacate.

3. The composition according to claim 1, wherein the content of the unsubstituted saturated dicarboxylic acid monoester compound is 50 to 300ppm.

4. A method of improving diesel lubricity comprising: and adding a saturated dicarboxylic acid monoester compound without substituent groups into the diesel oil in an amount of 10-400 ppm based on the mass of the diesel oil, wherein the saturated dicarboxylic acid monoester compound without substituent groups is selected from oxalic acid monoester, malonic acid monoester, glutaric acid monoester, adipic acid monoester, pimelic acid monoester, suberic acid monoester, azelaic acid monoester and sebacic acid monoester, and the ester groups contain C1-C30 hydrocarbon groups.

5. The process according to claim 4, wherein the unsubstituted saturated dicarboxylic acid monoester compound is selected from the group consisting of mono-tert-butyl malonate, monomethyl adipate, monoethyl adipate, monopropyl adipate, monobutyl adipate, monoisooctyl adipate, monoisononyl adipate, monomethyl azelate, monoethyl azelate, monopropyl azelate, monobutyl azelate, monoisooctyl azelate, monoisononyl azelate, monomethyl sebacate, monoethyl sebacate, monopropyl sebacate, monobutyl sebacate, monoisooctyl sebacate, monoisononyl sebacate.

6. The method according to claim 4, wherein the content of the unsubstituted saturated dicarboxylic acid monoester compound is 50 to 300ppm.