Fuel oil lubricity improver, process for its preparation and use

Abstract

A fuel lubricity improver and its application, said fuel lubricity improver comprising a dicarboxylic acid monool ether ester compound represented by structural formula (I), wherein R1 is a single bond, substituted or unsubstituted C. 1‑18 Divalent alkyl or C 2‑6 The divalent alkenyl group, or a group having a -R4-R5-R6- structure; R2 is CH2, CH2CH2, CH(CH3)CH2, CH2CH(CH3); n is an integer from 1 to 12; R3 is a substituted or unsubstituted C 1‑40 Hydrocarbon group; R4 and R6 are each independently a single bond, or a substituted or unsubstituted C. 1‑3 divalent alkyl; R5 is a substituted or unsubstituted C 3‑12 The fuel lubricity improver, which contains a divalent alicyclic group, can significantly improve the lubricity of fuel and requires a low dosage, thus significantly reducing the cost of using the improver.

Description

Technical Field

[0001] This application relates to the field of fuel additives, specifically to an ester-based fuel lubricity improver, its preparation method, and its application. Background Technology

[0002] Because low-sulfur diesel fuel has poor lubricity, it and ultra-low-sulfur diesel fuel are typically treated with lubricity improvers (also known as lubrication additives or anti-wear agents) to improve their lubrication performance. This method has advantages such as low cost, flexible production, and low pollution, and has received widespread attention in industry. Existing industrially used anti-wear agents for low-sulfur diesel fuel mainly include two types: acid-type and ester-type. The main components of acid-type anti-wear agents are long-chain unsaturated fatty acids such as oleic acid, linoleic acid, and linolenic acid, with typical products derived from refined tall oil fatty acids. Ester-type anti-wear agents are products of the esterification reaction of the above fatty acids with polyols. While using fatty acid-type anti-wear agents to solve diesel lubricity problems is relatively low-cost, the increasing stringency of diesel emission standards and the deterioration of lubricity lead to problems such as excessive dosage, resulting in excessive diesel acidity and increased corrosion risk. While using fatty acid ester-type anti-wear agents requires less dosage, it also carries the risks of high cost and emulsification and clouding of the diesel fuel upon contact with water.

[0003] CN106929112A discloses the application of alkenyl succinic acid monoester as an anti-wear agent for low-sulfur diesel fuel; CN113462443A discloses the application of monoesters generated by the reaction of unsaturated diacids / anhydrides with fatty alcohols or phenols as anti-wear agents for diesel fuel; CN113462441A discloses the application of cyclic dicarboxylic acid monoesters as anti-wear agents for diesel fuel.

[0004] Existing diesel anti-wear additives generally have a pour point as low as -20℃. For example, the Sinopec Group's anti-wear additive standard Q / SHCG 57-2017 stipulates that the pour point of fatty acid-based anti-wear additives should not exceed -12℃, and the pour point of fatty acid ester-based anti-wear additives should not exceed -16℃. When these anti-wear additives with higher pour points are used to formulate ultra-low pour point diesel fuel, additive precipitation may occur under extreme low temperature conditions, resulting in poor diesel fuel lubricity and the risk of clogging engine filters and causing poor fuel supply. Therefore, the development of low-pour-point anti-wear additive products for ultra-low pour point diesel fuel required in high-altitude and cold regions is a pressing technical problem that needs to be solved.

[0005] Compared to other fuels, gasoline is the lightest and also the least lubricating liquid fuel. Due to its extremely low content of natural anti-wear impurities, gasoline's inherent lubricating properties are exceptionally strong. Furthermore, new gasoline formulations contain significant amounts of hygroscopic oxygen-containing impurities (such as lower alcohols) and easily oxidized olefins, which negatively impact its lubricating performance. Improved gasoline lubricity not only reduces fuel injection pump wear and extends engine life but also improves energy efficiency and reduces fuel consumption. Similar to addressing the lubricity issues of aviation fuels and diesel fuels, an effective method to improve gasoline lubricity is to add anti-wear agents. Existing gasoline anti-wear agents are mostly based on aliphatic amines or ether amines, resulting in high production costs. Additionally, the prepared lubricating additives are nitrogen-containing compounds, which generate nitrogen oxides during gasoline combustion, causing emissions pollution and contradicting the principle of clean fuel use.

[0006] Therefore, there remains an urgent need in this field for fuel lubricity improvers that can significantly improve fuel lubricity and are low-cost, have low pour points, and are cleaner. Summary of the Invention

[0007] The first aspect of this application is to provide a low-pour-point fuel lubricity improver that not only significantly improves the lubricity of fuel, but also has a low pour point, is nitrogen-free, and can be used in cold regions.

[0008] A second aspect of this application provides a method for preparing a fuel lubricity improver.

[0009] A third aspect of this application is to provide a fuel composition.

[0010] The fourth aspect of this application is to provide a method for improving fuel lubricity.

[0011] The fifth aspect of this application is to provide the use of a dicarboxylic acid monool ether ester compound.

[0012] The sixth aspect of this application provides a dicarboxylic acid monool ether ester compound suitable as a fuel lubricity improver.

[0013] In a first aspect, this application provides a low-pour-point fuel lubricity improver comprising a dicarboxylic acid monool ether ester compound represented by structural formula (I):

[0014] (I)

[0015] Where R1 is a single bond, substituted or unsubstituted C 2-6 A divalent alkyl or alkenyl group, or a group having a -R4-R5-R6- structure, wherein R4 and R6 are each independently a single bond, or a substituted or unsubstituted C. 1-3divalent alkyl, R5 is a substituted or unsubstituted C 3-12 The divalent alicyclic group; R2 is methylene, ethylene, or isopropylene; n is an integer from 1 to 12; R3 is a substituted or unsubstituted C 1-40 Hydrocarbon group. The term "substituted" refers to a group substituted by at least one C. 1-4 Straight-chain or branched hydrocarbon group substitution.

[0016] In a second aspect, this application provides a method for preparing a fuel lubricity improver, comprising reacting a dicarboxylic acid having structural formula (II) or its anhydride with an alcohol ether or phenol ether having structural formula (III).

[0017] (II)

[0018] (III)

[0019] Where R1 is a single bond, substituted or unsubstituted C 2-6 A divalent alkyl or alkenyl group or a group having a -R4-R5-R6- structure, wherein R4 and R6 are each independently a single bond, or a substituted or unsubstituted C. 1-3 divalent alkyl, R5 is a substituted or unsubstituted C 3-12 The divalent alicyclic group; R2 is methylene, ethylene, or isopropylene; n is an integer from 1 to 12; R3 is a substituted or unsubstituted C 1-40 Hydrocarbon group.

[0020] In a third aspect, this application provides a fuel composition comprising fuel components and a lubricity improver according to this application, wherein the content of the lubricity improver is 5-400 ppm based on 100% by mass of the fuel.

[0021] In a fourth aspect, this application provides a method for improving fuel lubricity, comprising adding the lubricity improver described in this application to fuel, wherein the amount of the lubricity improver is 5-400 ppm based on 100% of the mass of the fuel.

[0022] In a fifth aspect, this application provides the use of a dicarboxylic acid monool ether ester compound as a fuel lubricity improver, wherein the dicarboxylic acid monool ether ester compound is as shown in structural formula (I).

[0023] In a sixth aspect, this application provides a dicarboxylic acid monool ether ester compound suitable as a fuel lubricity improver.

[0024] The fuel lubricity improver of this application is made from readily available raw materials and is easy to produce. It can significantly improve the lubricity of fuel and requires a low amount of additive, which can significantly reduce the cost of using the lubricity improver.

[0025] Meanwhile, the dicarboxylic acid monool ether ester compound of the present invention has a low pour point and does not precipitate at low temperatures, making it particularly suitable for use in cold regions as a fuel lubricity improver.

[0026] Furthermore, the fuel lubricity improver of this application is nitrogen-free, will not emit nitrogen oxides during use, and will not cause the risk of emulsification and turbidity of diesel fuel. Its anti-emulsification effect is comparable to that of fatty acid-type lubricity improvers and is superior to that of fatty acid glyceride-type lubricity improvers. Detailed Implementation

[0027] The specific embodiments of this application are described in detail below. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this application.

[0028] Any specific numerical values ​​disclosed herein (including the endpoints of numerical ranges) are not limited to their exact values, but should be understood to also include values ​​close to the exact value, such as all possible values ​​within ±5% of the exact value. Furthermore, with respect to the disclosed numerical ranges, one or more new numerical ranges can be obtained by arbitrarily combining the endpoint values ​​of the range, the endpoint values ​​with specific point values ​​within the range, and the specific point values ​​themselves; these new numerical ranges should also be considered as specifically disclosed herein.

[0029] Unless otherwise stated, the terms used herein have the same meaning as commonly understood by those skilled in the art, and if a term is defined herein and its definition differs from the common understanding in the art, the definition herein shall prevail.

[0030] In this application, the term "divalent" group refers to a group obtained by removing two hydrogen atoms from the corresponding compound; for example, the term "C" refers to a group obtained by removing two hydrogen atoms from the compound. 2-6 "Divalent alkenyl" refers to a group obtained by removing two hydrogen atoms from a straight-chain or branched olefin having 2-6 carbon atoms, such as ethylene, propylene, 1-butene, 2-butene, isobutene, pentene, and hexene. The carbon-carbon double bond can be located on the main chain or on the side chain of this group. The term "C" is also relevant. 1-3 "Divalent alkyl" refers to a group obtained by removing two hydrogen atoms from an alkyl group having 1-3 carbon atoms, such as methylene, ethylene, and propylene; the term "C" 3-12 "Divalent alicyclic group" refers to a group obtained by removing two hydrogen atoms from a saturated or unsaturated alicyclic hydrocarbon with 3-12 carbon atoms, such as cyclopropane, cyclobutane, cyclopentane, cyclopentene, cyclohexane, cyclohexene, etc.

[0031] In this application, the term "hydrocarbon group" refers to a group obtained by removing a hydrogen atom from an aliphatic hydrocarbon, alicyclic hydrocarbon, or aromatic hydrocarbon, wherein the term "aliphatic hydrocarbon" refers to a straight-chain or branched, saturated or unsaturated hydrocarbon. For example, as C 1-40 Examples of hydrocarbon groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, n-hexyl, n-octyl, isooctyl, n-nonyl, isononyl, n-decyl, isodecyl, n-undecyl, isoundecyl, n-dodecyl, n-tridecyl, isotridecyl, 3-hexen-1-yl, octadecenyl, cyclohexyl, p-nonylphenyl, benzyl, etc.

[0032] In this application, except where expressly stated, any matters or issues not mentioned herein shall be directly applicable to those known in the art without any modification. Furthermore, any implementation described herein may be freely combined with one or more other implementations described herein, and the resulting technical solutions or concepts shall be considered part of the original disclosure or original record of this application, and should not be regarded as new content not disclosed or anticipated herein, unless those skilled in the art consider the combination to be clearly unreasonable.

[0033] As described above, in a first aspect, this application provides a fuel lubricity improver comprising a dicarboxylic acid monool ether ester compound represented by structural formula (I):

[0034] (I)

[0035] Where R1 is a single bond, substituted or unsubstituted C 1-18 Divalent alkyl chain or C 2-6 A divalent alkenyl group or a group having a -R4-R5-R6- structure, wherein R4 and R6 are each independently a single bond, or a substituted or unsubstituted C. 1-3 divalent alkyl, R5 is a substituted or unsubstituted C 3-12 The divalent alicyclic group; R2 is methylene, ethylene, or isopropylene; n is an integer from 1 to 12; R3 is a substituted or unsubstituted C 1-40 Hydrocarbon group.

[0036] The term "replaced" refers to that which is replaced by at least one C 1-4 Straight-chain or branched hydrocarbon group substitution.

[0037] In a preferred embodiment:

[0038] R1 is a single bond, substituted or unsubstituted C 2-8 Divalent alkyl chain or C 2-4 The divalent alkenyl group, or a group having a -R4-R5-R6- structure, where R4 and R6 are each independently a single bond or a methylene group, and R5 is a substituted or unsubstituted C- group.3-8 Divalent alicyclic group;

[0039] R2 can be CH2, CH2CH2, CH(CH3)CH2, or CH2CH(CH3);

[0040] R3 represents substituted or unsubstituted C. 1-18 Hydrocarbon group, preferably C 1-18 Straight-chain or branched hydrocarbon group, C 4-18 Alicyclic hydrocarbon groups, and C 7-18 The aryl-substituted hydrocarbon group or hydrocarbon-substituted aryl group is most preferably C1-12 alkyl, alkenyl, phenyl and benzyl;

[0041] n is an integer selected from 1 to 10, especially an integer from 1 to 6, for example, n is 1, 2, 3 or 4.

[0042] In a preferred embodiment, the fuel lubricity improver of this application contains an unsaturated dicarboxylic acid monool ether ester compound as shown in structural formula (I-1):

[0043] Structural formula (I-1)

[0044] Where m is an integer from 2 to 6, preferably an integer from 2 to 4, and the definitions and preferred implementations of n, R2, and R3 are as described in structural formula (I).

[0045] According to this application, the unsaturated dicarboxylic acid monool ether ester compound refers to a C-carbon compound containing a carbon-carbon unsaturated double bond in its molecule. 4-8 Monoesterified compounds in which any one of the carboxyl groups is esterified.

[0046] In a preferred embodiment, when m is 2, the compound represented by structural formula (I-2) is maleic acid monool ether ester or fumarate monool ether ester; when m is 3, the compound represented by structural formula (I-2) is itaconic acid monool ether ester, citraconic acid monool ether ester (methyl maleic acid monool ether ester), methyl fumarate monool ether ester (methyl fumarate monool ether ester), etc.; when m is 4, the compound represented by structural formula (I-2) is preferably 2,3-dimethyl maleic acid monool ether ester, ethyl maleic acid monool ether ester, etc.

[0047] In some particularly preferred embodiments, the dicarboxylic acid monoester compound is selected from maleic acid monool ether ester, itaconic acid monool ether ester, citraconic acid monool ether ester, 2,3-dimethylmaleic acid monool ether ester, or any combination thereof.

[0048] More preferably, the dicarboxylic acid monool ether ester compound is selected from maleic acid monool ether esters as shown in structural formula (I-1-1):

[0049] Structural formula (I-1-1)

[0050] The definitions and preferred implementations of n, R2, and R3 are as described in structural formula (I).

[0051] When n is 1, preferred specific examples include mono(methoxymethanol) maleate, mono(ethylene glycol monomethyl ether) maleate, mono(ethylene glycol monoethyl ether) maleate, mono(ethylene glycol monopropyl ether) maleate, mono(ethylene glycol monobutyl ether) maleate, mono(ethylene glycol monoisobutyl ether) maleate, mono(ethylene glycol monotert-butyl ether) maleate, mono(ethylene glycol monopentyl ether) maleate, mono(ethylene glycol monohexyl ether) maleate, and mono(ethylene glycol monoheptyl ether) maleate. Ethylene glycol monooctyl ether (EDGME), Ethylene glycol monoisooctyl ether (EDGME), Ethylene glycol monononyl ether (EDGME), Ethylene glycol monoisononyl ether (EDGME), Ethylene glycol monodecyl ether (EDGME), Ethylene glycol monoisodecyl ether (EDGME), Ethylene glycol monolaurate (EDGME), Ethylene glycol monoisotridecyl ether (EDGME), Ethylene glycol monobenzyl ether (EDGME), Ethylene glycol monononylphenol ether (EDGME), Ethylene glycol monododecylphenol ether (EDGME), etc. Maleate mono(ethylene glycol monooleyl ether), maleate mono(propylene glycol monomethyl ether), maleate mono(propylene glycol monoethyl ether), maleate mono(propylene glycol monopropyl ether), maleate mono(propylene glycol monobutyl ether), maleate mono(propylene glycol monoisobutyl ether), maleate mono(propylene glycol monotert-butyl ether), maleate mono(propylene glycol monopentyl ether), maleate mono(propylene glycol monohexyl ether), maleate mono(propylene glycol monoheptyl ether), maleate mono(propylene glycol monooctyl ether), maleate mono(propylene glycol mono(propylene glycol monoethyl ether)). Propylene glycol monoisooctyl ether (PODE), maleate mono(propylene glycol monononyl ether) ester, maleate mono(propylene glycol monoisononyl ether) ester, maleate mono(propylene glycol monodecyl ether) ester, maleate mono(propylene glycol monoisoundeyl ether) ester, maleate mono(propylene glycol monolaurate ether) ester, maleate mono(propylene glycol monoisotridecyl ether) ester, maleate mono(propylene glycol monobenzyl ether) ester, maleate mono(propylene glycol monononylphenol ether) ester, maleate mono(propylene glycol monododecylphenol ether) ester, maleate mono(propylene glycol monooleyl ether) ester, etc.

[0052] When n is 2, preferred specific examples include mono(diethylene glycol monomethyl ether) maleate, mono(diethylene glycol monoethyl ether) maleate, mono(diethylene glycol monopropyl ether) maleate, mono(diethylene glycol monobutyl ether) maleate, mono(diethylene glycol monoisobutyl ether) maleate, mono(diethylene glycol monotert-butyl ether) maleate, mono(diethylene glycol monopentyl ether) maleate, mono(diethylene glycol monohexyl ether) maleate, and mono(diethylene glycol monooctyl ether) maleate. Isooctyl ether, maleate mono(diethylene glycol monononyl ether), maleate mono(diethylene glycol monoisononyl ether), maleate mono(diethylene glycol monodecyl ether), maleate mono(diethylene glycol monoisoundecyl ether), maleate mono(diethylene glycol monolaurate ether), maleate mono(diethylene glycol monoisotridecyl ether), maleate mono(diethylene glycol monobenzyl ether), maleate mono(diethylene glycol monononylphenol ether), maleate mono(diethylene glycol monododecylphenol ether), maleate mono(diethylene glycol ... Mono-oleic alcohol ether ester, mono(dipropylene glycol monomethyl ether) maleate, mono(dipropylene glycol monoethyl ether) maleate, mono(dipropylene glycol monopropyl ether) maleate, mono(dipropylene glycol monobutyl ether) maleate, mono(dipropylene glycol monoisobutyl ether) maleate, mono(dipropylene glycol monotert-butyl ether) maleate, mono(dipropylene glycol monopentyl ether) maleate, mono(dipropylene glycol monohexyl ether) maleate, mono(dipropylene glycol monooctyl ether) maleate, mono(dipropylene glycol monoisooctyl ether) maleate, maleate ... Mono(dipropylene glycol monononyl ether) ester, mono(dipropylene glycol monoisononyl ether) ester, mono(dipropylene glycol monodecyl ether) ester, mono(dipropylene glycol monoisoundeyl ether) ester, mono(dipropylene glycol monolaurate ether) ester, mono(dipropylene glycol monoisotridecyl ether) ester, mono(dipropylene glycol monobenzyl ether) ester, mono(dipropylene glycol monononylphenol ether) ester, mono(dipropylene glycol monododecylphenol ether) ester, mono(dipropylene glycol monooleyl ether) ester, etc.

[0053] When n is 3, preferred specific examples include mono(triethylene glycol monomethyl ether) maleate, mono(triethylene glycol monoethyl ether) maleate, mono(triethylene glycol monopropyl ether) maleate, mono(triethylene glycol monobutyl ether) maleate, mono(triethylene glycol monoisobutyl ether) maleate, mono(triethylene glycol monotert-butyl ether) maleate, mono(triethylene glycol monopentyl ether) maleate, mono(triethylene glycol monohexyl ether) maleate, mono(triethylene glycol monooctyl ether) maleate, and mono(triethylene glycol monomethyl ether) maleate. Isooctyl ether, maleate mono(triethylene glycol monononyl ether), maleate mono(triethylene glycol monoisononyl ether), maleate mono(triethylene glycol monodecyl ether), maleate mono(triethylene glycol monoisoundecyl ether), maleate mono(triethylene glycol monolaurate ether), maleate mono(triethylene glycol monoisotridecyl ether), maleate mono(triethylene glycol monobenzyl ether), maleate mono(triethylene glycol monononylphenol ether), maleate mono(triethylene glycol monododecylphenol ether), maleate mono(triethylene glycol mono(triethylene glycol mono(triethylene glycol mono(benzyl ether)), maleate mono(triethylene glycol mono(nonylphenol ether)), maleate mono(triethylene glycol mono(dodecylphenol ether)), maleate mono(triethylene glycol mono(benzyl ether)) Mono-oleic alcohol ether ester, mono(tripropylene glycol monomethyl ether) ester, mono(tripropylene glycol monoethyl ether) ester, mono(tripropylene glycol monopropyl ether) ester, mono(tripropylene glycol monobutyl ether) ester, mono(tripropylene glycol monoisobutyl ether) ester, mono(tripropylene glycol monotert-butyl ether) ester, mono(tripropylene glycol monopentyl ether) ester, mono(tripropylene glycol monohexyl ether) ester, mono(tripropylene glycol monooctyl ether) ester, mono(tripropylene glycol monoisooctyl ether) ester, maleic acid mono-oleic alcohol ether ester, maleic acid mono-oleic alcohol mono-isooctyl ether ester, maleic acid mono-oleic alcohol mono-isooctyl ether, maleic acid mono-oleic alcohol mono-oleic alcohol ether ... Mono(tripropylene glycol monononyl ether) ester, mono(tripropylene glycol monoisononyl ether) ester, mono(tripropylene glycol monodecyl ether) ester, mono(tripropylene glycol monoisoundeyl ether) ester, mono(tripropylene glycol monolaurate ether) ester, mono(tripropylene glycol monoisotridecyl ether) ester, mono(tripropylene glycol monobenzyl ether) ester, mono(tripropylene glycol monononylphenol ether) ester, mono(tripropylene glycol monododecylphenol ether) ester, mono(tripropylene glycol monooleyl ether) ester, etc.

[0054] In a preferred embodiment, the fuel lubricity improver of this application contains a saturated dicarboxylic acid monool ether ester compound as shown in structural formula (I-2):

[0055] Structural formula (I-2)

[0056] Where p is an integer from 0 to 18, preferably an integer from 2 to 8, and the definitions and preferred implementations of n, R2, and R3 are as described in structural formula (I).

[0057] Specifically, the saturated dicarboxylic acid monool ether ester compound represented by structural formula I-2 can be selected from oxalic acid monool ether ester, malonic acid monool ether ester, succinic acid monool ether ester, glutaric acid monool ether ester, adipic acid monool ether ester, pimelic acid monool ether ester, octanoic acid monool ether ester, azelaic acid monool ether ester, sebacic acid monool ether ester, undecanoic acid monool ether ester, dodecanoic acid monool ether ester, tridecanoic acid monool ether ester, tetradecanoic acid monool ether ester, hexadecanoic acid monool ether ester, octadecanoic acid monool ether ester, etc. Succinic acid monool ether ester, glutaric acid monool ether ester, adipic acid monool ether ester, azelaic acid monool ether ester, and sebacic acid monool ether ester are further preferred.

[0058] In a preferred embodiment of monosuccinate monomethyl ether ester, monosuccinate mono(ethylene glycol monomethyl ether), monosuccinate mono(ethylene glycol monobutyl ether), monosuccinate mono(diethylene glycol monobutyl ether), monosuccinate mono(propylene glycol monobutyl ether), monosuccinate mono(dipropylene glycol monobutyl ether), monosuccinate mono(ethylene glycol monoisopentyl ether), monosuccinate mono(diethylene glycol monoisopentyl ether), monosuccinate mono(ethylene glycol monoisooctyl ether), monosuccinate mono(diethylene glycol monoisooctyl ether), monosuccinate mono(propylene glycol monoisooctyl ether), monosuccinate mono(ethylene glycol monoisononyl ether), monosuccinate mono(diethylene glycol monoisononyl ether), monosuccinate mono(ethylene glycol monoisoundeyl ether), etc., are further preferred.

[0059] In a preferred embodiment of mono- and mono-ethylene glycol monomethyl ether glutarate, the following are further preferred: mono- and mono-butyl glutarate, mono- and mono-diethylene glycol monobutyl glutarate, mono- and mono-propylene glycol monobutyl glutarate, mono- and mono-propylene glycol monobutyl glutarate, mono- and mono-ethylene glycol monoisopentyl glutarate, mono- and mono-ethylene glycol monoisopentyl glutarate, mono- and mono-ethylene glycol monoisooctyl glutarate, mono- and mono-propylene glycol monoisooctyl glutarate, mono- and mono-propylene glycol monoisooctyl glutarate, mono- and mono-ethylene glycol monoisononyl glutarate, mono- and mono-ethylene glycol monoisoundeyl glutarate, etc.

[0060] In a preferred embodiment, the fuel lubricity improver of this application contains a cyclic dicarboxylic acid monool ether ester compound as shown in structural formula (I-3):

[0061]

[0062] Structural formula (I-3)

[0063] Where x is an integer from 0 to 3, y1 and y2 are integers from 0 to 2, z is an integer from 1 to 8, a is an integer from 0 to 8, and the definitions and preferred implementations of n, R2, and R3 are as described in structural formula (I).

[0064] When x is 0, y1 and y2 are 1, z is 1, and a is 0, the monoester compound with structural formula I-2 is 1,2-cyclopropanedicarboxylic acid monool ether ester.

[0065] When x is 1, y1, y2 are 1, z is 1, and a is 0, the monoester compound with structural formula I-2 is a 1,2-cyclopropanediacetic acid monool ether ester.

[0066] When x is 0, y1 and y2 are 2, z is 1, and a is 2, the monoester compound with structural formula I-2 is 1,1-cyclopropanedicarboxylic acid monool ether ester.

[0067] When x is 0, y1 and y2 are 1, z is 2 and a is 0, the monoester compound with structural formula I-2 is 1,2-cyclobutanedicarboxylic acid monool ether ester.

[0068] When x is 1, y1 and y2 are 1, z is 2 and a is 0, the monoester compound with structural formula I-2 is 1,2-cyclobutanediacetic acid monool ether ester.

[0069] When x is 0, y1 and y2 are 1, z is 3 and a is 0, the monoester compound with structural formula I-2 is 1,2-cyclopentanedicarboxylic acid monool ether ester.

[0070] When x is 1, y1 and y2 are 1, z is 3, and a is 0, the monoester compound with structural formula I-2 is a 1,2-cyclopentanediacetic acid monool ether ester.

[0071] When x is 0, y1 and y2 are 1, z is 4 and a is 0, the monoester compound with structural formula I-2 is 1,2-cyclohexanedicarboxylic acid monool ether ester.

[0072] When x is 1, y1 and y2 are 1, z is 4 and a is 0, the monoester compound with structural formula I-2 is 1,2-cyclohexanediacetic acid monool ether ester.

[0073] When x is 0, y1 and y2 are 1, z is 4 and a is 2, the monoester compound with structural formula I-2 is 4-cyclohexene-1,2-dicarboxylic acid monool ether ester (tetrahydrophthalic acid monool ether ester).

[0074] When x is 1, y1 and y2 are 1, z is 4 and a is 2, the monoester compound with structural formula I-2 is 4-cyclohexene-1,2-diacetic acid monool ether ester.

[0075] When x is 0, y1 and y2 are 0, z is 4, and a is 4, the monoester compound with structural formula I-2 is a phthalic acid monool ether ester.

[0076] When x is 1, y1 and y2 are 0, z is 4, and a is 4, the monoester compound with structural formula I-2 is a phthalic acid monool ether ester.

[0077] When x is 0, y1 and y2 are 1, z is 5 and a is 0, the monoester compound with structural formula I-2 is methyl-1,2-cyclohexanedicarboxylic acid monool ether ester (methyl hexahydrophthalic acid monool ether ester).

[0078] When x is 0, y1 and y2 are 1, z is 5 and a is 2, the monoester compound with structural formula I-2 is methyltetrahydrophthalic acid monool ether ester, etc.

[0079] The cyclic dicarboxylic acid monoester compound is preferably 1,2-cyclopentadicarboxylic acid monoethanol ether ester, 1,2-cyclohexanedicarboxylic acid monoethanol ether ester, tetrahydrophthalic acid monoethanol ether ester, phthalic acid monoethanol ether ester, methylhexahydrophthalic acid monoethanol ether ester, methyltetrahydrophthalic acid monoethanol ether ester, etc. More preferably, the dicarboxylic acid monoethanol ether ester compound is selected from 1,2-cyclohexanedicarboxylic acid monoethanol ether ester, tetrahydrophthalic acid monoethanol ether ester, methylhexahydrophthalic acid monoethanol ether ester, methyltetrahydrophthalic acid monoethanol ether ester, or any combination thereof.

[0080] Further preferably, n is an integer from 1 to 10, especially an integer from 1 to 6, for example, n is 1, 2, 3 or 4; R3 is a substituted or unsubstituted C1-18 hydrocarbon group, more preferably a C1-12 alkyl group.

[0081] When n is 1, specific examples include the following compounds:

[0082] 1,2-Cyclohexanedicarboxylate mono(methoxymethanol), 1,2-Cyclohexanedicarboxylate mono(ethylene glycol monomethyl ether), 1,2-Cyclohexanedicarboxylate mono(ethylene glycol monoethyl ether), 1,2-Cyclohexanedicarboxylate mono(ethylene glycol monopropyl ether), 1,2-Cyclohexanedicarboxylate mono(ethylene glycol monobutyl ether), 1,2-Cyclohexanedicarboxylate mono(ethylene glycol monoisobutyl ether), 1,2-Cyclohexanedicarboxylate mono(ethylene glycol monotert-butyl ether), 1,2-Cyclohexanedicarboxylate mono(ethylene glycol monopentyl ether), 1,2-Cyclohexanedicarboxylate mono(ethylene glycol monohexyl ether), 1,2-Cyclohexanedicarboxylate mono(ethylene glycol monoheptyl ether), 1,2-Cyclohexanedicarboxylate mono(ethylene glycol monooct ... Formate mono(ethylene glycol monoisooctyl ether), 1,2-cyclohexanedicarboxylate mono(ethylene glycol monononyl ether), 1,2-cyclohexanedicarboxylate mono(ethylene glycol monoisononyl ether), 1,2-cyclohexanedicarboxylate mono(ethylene glycol monodecyl ether), 1,2-cyclohexanedicarboxylate mono(ethylene glycol monoisoundecyl ether), 1,2-cyclohexanedicarboxylate mono(ethylene glycol monolauryl ether), 1,2-cyclohexanedicarboxylate mono(ethylene glycol monoisotridecyl ether), 1,2-cyclohexanedicarboxylate mono(ethylene glycol monobenzyl ether), 1,2-cyclohexanedicarboxylate mono(ethylene glycol monononylphenol ether), 1,2-cyclohexanedicarboxylate mono(ethylene glycol monododecylphenol ether), 1,2-cyclohexanedicarboxylate mono(ethylene glycol monooleyl ether), etc.

[0083] 1,2-Cyclohexanedicarboxylate mono(propylene glycol monomethyl ether), 1,2-Cyclohexanedicarboxylate mono(propylene glycol monoethyl ether), 1,2-Cyclohexanedicarboxylate mono(propylene glycol monopropyl ether), 1,2-Cyclohexanedicarboxylate mono(propylene glycol monobutyl ether), 1,2-Cyclohexanedicarboxylate mono(propylene glycol monoisobutyl ether), 1,2-Cyclohexanedicarboxylate mono(propylene glycol monotert-butyl ether), 1,2-Cyclohexanedicarboxylate mono(propylene glycol monopentyl ether), 1,2-Cyclohexanedicarboxylate mono(propylene glycol monohexyl ether), 1,2-Cyclohexanedicarboxylate mono(propylene glycol monoheptyl ether), 1,2-Cyclohexanedicarboxylate mono(propylene glycol monoisobutyl ether), 1,2-Cyclohexanedicarboxylate mono(propylene glycol monoisobutyl ether) Octyl ether, 1,2-cyclohexanedicarboxylate mono(propylene glycol monononyl ether), 1,2-cyclohexanedicarboxylate mono(propylene glycol monoisononyl ether), 1,2-cyclohexanedicarboxylate mono(propylene glycol monodecyl ether), 1,2-cyclohexanedicarboxylate mono(propylene glycol monoisoundecyl ether), 1,2-cyclohexanedicarboxylate mono(propylene glycol monolauryl ether), 1,2-cyclohexanedicarboxylate mono(propylene glycol monoisotridecyl ether), 1,2-cyclohexanedicarboxylate mono(propylene glycol monobenzyl ether), 1,2-cyclohexanedicarboxylate mono(propylene glycol monononylphenol ether), 1,2-cyclohexanedicarboxylate mono(propylene glycol monododecylphenol ether), 1,2-cyclohexanedicarboxylate mono(propylene glycol monooleyl ether), etc.

[0084] Methyltetrahydrophthalic acid mono(methoxymethanol), methyltetrahydrophthalic acid mono(ethylene glycol monomethyl ether), methyltetrahydrophthalic acid mono(ethylene glycol monoethyl ether), methyltetrahydrophthalic acid mono(ethylene glycol monopropyl ether), methyltetrahydrophthalic acid mono(ethylene glycol monobutyl ether), methyltetrahydrophthalic acid mono(ethylene glycol monoisobutyl ether), methyltetrahydrophthalic acid mono(ethylene glycol monotert-butyl ether), methyltetrahydrophthalic acid mono(ethylene glycol monopentyl ether), methyltetrahydrophthalic acid mono(ethylene glycol monohexyl ether), methyltetrahydrophthalic acid mono(ethylene glycol monoheptyl ether), methyltetrahydrophthalic acid mono(ethylene glycol monooctyl ether), methyltetrahydrophthalic acid mono(ethylene glycol monooctyl ether), methyltetrahydrophthalic acid mono(ethylene glycol monooctyl ether), methyltetrahydrophthalic acid mono(ethylene glycol monooctyl ether), methyltetrahydrophthalic acid mono(ethylene glycol monoethyl ... Formate mono(ethylene glycol monoisooctyl ether), methyltetrahydrophthalic acid mono(ethylene glycol monononyl ether), methyltetrahydrophthalic acid mono(ethylene glycol monoisononyl ether), methyltetrahydrophthalic acid mono(ethylene glycol monodecyl ether), methyltetrahydrophthalic acid mono(ethylene glycol monoisoundecyl ether), methyltetrahydrophthalic acid mono(ethylene glycol monolauryl ether), methyltetrahydrophthalic acid mono(ethylene glycol monoisotridecyl ether), methyltetrahydrophthalic acid mono(ethylene glycol monobenzyl ether), methyltetrahydrophthalic acid mono(ethylene glycol monononylphenol ether), methyltetrahydrophthalic acid mono(ethylene glycol monododecylphenol ether), methyltetrahydrophthalic acid mono(ethylene glycol monooleyl ether), etc.

[0085] Methyltetrahydrophthalic acid mono(propylene glycol monomethyl ether), methyltetrahydrophthalic acid mono(propylene glycol monoethyl ether), methyltetrahydrophthalic acid mono(propylene glycol monopropyl ether), methyltetrahydrophthalic acid mono(propylene glycol monobutyl ether), methyltetrahydrophthalic acid mono(propylene glycol monoisobutyl ether), methyltetrahydrophthalic acid mono(propylene glycol monotert-butyl ether), methyltetrahydrophthalic acid mono(propylene glycol monopentyl ether), methyltetrahydrophthalic acid mono(propylene glycol monohexyl ether), methyltetrahydrophthalic acid mono(propylene glycol monoheptyl ether), methyltetrahydrophthalic acid mono(propylene glycol monooctyl ether), methyltetrahydrophthalic acid mono(propylene glycol monoisobutyl ether) Octyl ether, methyltetrahydrophthalic acid mono(propylene glycol monononyl ether), methyltetrahydrophthalic acid mono(propylene glycol monoisononyl ether), methyltetrahydrophthalic acid mono(propylene glycol monodecyl ether), methyltetrahydrophthalic acid mono(propylene glycol monoisoundecyl ether), methyltetrahydrophthalic acid mono(propylene glycol monolauryl ether), methyltetrahydrophthalic acid mono(propylene glycol monoisotridecyl ether), methyltetrahydrophthalic acid mono(propylene glycol monobenzyl ether), methyltetrahydrophthalic acid mono(propylene glycol monononylphenol ether), 1,2-cyclohexanedicarboxylic acid mono(propylene glycol monododecylphenol ether), methyltetrahydrophthalic acid mono(propylene glycol monooleyl ether), etc.

[0086] Methylhexyl phthalate mono(methoxymethanol), methylhexyl phthalate mono(ethylene glycol monomethyl ether), methylhexyl phthalate mono(ethylene glycol monoethyl ether), methylhexyl phthalate mono(ethylene glycol monopropyl ether), methylhexyl phthalate mono(ethylene glycol monobutyl ether), methylhexyl phthalate mono(ethylene glycol monoisobutyl ether), methylhexyl phthalate mono(ethylene glycol monotert-butyl ether), methylhexyl phthalate mono(ethylene glycol monoheptanyl ether), methylhexyl phthalate mono(ethylene glycol monoheptyl ether), methylhexyl phthalate mono(ethylene glycol monooctyl ether), methylhexyl phthalate mono(ethylene glycol monooctyl ether), methylhexyl phthalate mono(ethylene glycol monooctyl ether), methylhexyl phthalate mono(ethylene glycol monooctyl ether), methylhexyl phthalate mono(ethylene glycol monoethyl ... Formate mono(ethylene glycol monoisooctyl ether), methyl hexahydrophthalic acid mono(ethylene glycol monononyl ether), methyl hexahydrophthalic acid mono(ethylene glycol monoisononyl ether), methyl hexahydrophthalic acid mono(ethylene glycol monodecyl ether), methyl hexahydrophthalic acid mono(ethylene glycol monoisoundecyl ether), methyl hexahydrophthalic acid mono(ethylene glycol monolauryl ether), methyl hexahydrophthalic acid mono(ethylene glycol monoisotridecyl ether), methyl hexahydrophthalic acid mono(ethylene glycol monobenzyl ether), methyl hexahydrophthalic acid mono(ethylene glycol monononylphenol ether), methyl hexahydrophthalic acid mono(ethylene glycol monododecylphenol ether), methyl hexahydrophthalic acid mono(ethylene glycol monooleyl ether), etc.

[0087] Methylhexyl phthalate mono(propylene glycol monomethyl ether), methylhexyl phthalate mono(propylene glycol monoethyl ether), methylhexyl phthalate mono(propylene glycol monopropyl ether), methylhexyl phthalate mono(propylene glycol monobutyl ether), methylhexyl phthalate mono(propylene glycol monoisobutyl ether), methylhexyl phthalate mono(propylene glycol monotert-butyl ether), methylhexyl phthalate mono(propylene glycol monopentyl ether), methylhexyl phthalate mono(propylene glycol monoheptyl ether), methylhexyl phthalate mono(propylene glycol monooctyl ether), methylhexyl phthalate mono(propylene glycol monoisobutyl ether) Methylhexyl phthalate mono(propylene glycol monononyl ether), methylhexyl phthalate mono(propylene glycol monoisononyl ether), methylhexyl phthalate mono(propylene glycol monodecyl ether), methylhexyl phthalate mono(propylene glycol monoisounde ether), methylhexyl phthalate mono(propylene glycol monolauryl ether), methylhexyl phthalate mono(propylene glycol monoisotridecyl ether), methylhexyl phthalate mono(propylene glycol monobenzyl ether), methylhexyl phthalate mono(propylene glycol monononylphenol ether), methylhexyl phthalate mono(propylene glycol monododecylphenol ether), methylhexyl phthalate mono(propylene glycol monooleyl ether), etc.

[0088] When n is 2, specific examples include:

[0089] 1,2-Cyclohexadicarboxylate mono(diethylene glycol monomethyl ether), 1,2-Cyclohexadicarboxylate mono(diethylene glycol monoethyl ether), 1,2-Cyclohexadicarboxylate mono(diethylene glycol monopropyl ether), 1,2-Cyclohexadicarboxylate mono(diethylene glycol monobutyl ether), 1,2-Cyclohexadicarboxylate mono(diethylene glycol monoisobutyl ether), 1,2-Cyclohexadicarboxylate mono(diethylene glycol monotert-butyl ether), 1,2-Cyclohexadicarboxylate mono(diethylene glycol monopentyl ether), 1,2-Cyclohexadicarboxylate mono(diethylene glycol monohexyl ether), 1,2-Cyclohexadicarboxylate mono(diethylene glycol monooctyl ether), 1,2-Cyclohexadicarboxylate mono(diethylene glycol monoiso ... Mono(diethylene glycol monononyl ether) adipate, mono(diethylene glycol monoisononyl ether) adipate, mono(diethylene glycol monodecyl ether) adipate, mono(diethylene glycol monoisoundecyl ether) adipate, mono(diethylene glycol monolauryl ether) adipate, mono(diethylene glycol monoisotridecyl ether) adipate, mono(diethylene glycol monobenzyl ether) adipate, mono(diethylene glycol monononylphenol ether) adipate, mono(diethylene glycol monododecylphenol ether) adipate, mono(diethylene glycol monooleyl ether) adipate, mono(diethylene glycol monooleyl ether) adipate.

[0090] 1,2-Cyclohexadicarboxylate mono(dipropylene glycol monomethyl ether), 1,2-Cyclohexadicarboxylate mono(dipropylene glycol monoethyl ether), 1,2-Cyclohexadicarboxylate mono(dipropylene glycol monopropyl ether), 1,2-Cyclohexadicarboxylate mono(dipropylene glycol monobutyl ether), 1,2-Cyclohexadicarboxylate mono(dipropylene glycol monoisobutyl ether), 1,2-Cyclohexadicarboxylate mono(dipropylene glycol monotert-butyl ether), 1,2-Cyclohexadicarboxylate mono(dipropylene glycol monopentyl ether), 1,2-Cyclohexadicarboxylate mono(dipropylene glycol monohexyl ether), 1,2-Cyclohexadicarboxylate mono(dipropylene glycol monooctyl ether), 1,2-Cyclohexadicarboxylate mono(dipropylene glycol monoiso ... Adipate mono(dipropylene glycol monononyl ether), 1,2-cyclohexanedicarboxylate mono(dipropylene glycol monoisononyl ether), 1,2-cyclohexanedicarboxylate mono(dipropylene glycol monodecyl ether), 1,2-cyclohexanedicarboxylate mono(dipropylene glycol monoisoundecyl ether), 1,2-cyclohexanedicarboxylate mono(dipropylene glycol monolauryl ether), 1,2-cyclohexanedicarboxylate mono(dipropylene glycol monoisotridecyl ether), 1,2-cyclohexanedicarboxylate mono(dipropylene glycol monobenzyl ether), 1,2-cyclohexanedicarboxylate mono(dipropylene glycol monononylphenol ether), 1,2-cyclohexanedicarboxylate mono(dipropylene glycol monododecylphenol ether), 1,2-cyclohexanedicarboxylate mono(dipropylene glycol monooleyl ether), etc.

[0091] Methyltetrahydrophthalic acid mono(diethylene glycol monomethyl ether), methyltetrahydrophthalic acid mono(diethylene glycol monoethyl ether), methyltetrahydrophthalic acid mono(diethylene glycol monopropyl ether), methyltetrahydrophthalic acid mono(diethylene glycol monobutyl ether), methyltetrahydrophthalic acid mono(diethylene glycol monoisobutyl ether), methyltetrahydrophthalic acid mono(diethylene glycol monotert-butyl ether), methyltetrahydrophthalic acid mono(diethylene glycol monopentyl ether), methyltetrahydrophthalic acid mono(diethylene glycol monohexyl ether), methyltetrahydrophthalic acid mono(diethylene glycol monooctyl ether), methyltetrahydrophthalic acid mono(diethylene glycol monoiso ... Mono(diethylene glycol monononyl ether) phthalate, methyltetrahydrophthalate mono(diethylene glycol monoisononyl ether) phthalate, methyltetrahydrophthalate mono(diethylene glycol monodecyl ether) phthalate, methyltetrahydrophthalate mono(diethylene glycol monoisoundecyl ether) phthalate, methyltetrahydrophthalate mono(diethylene glycol monolauryl ether) phthalate, methyltetrahydrophthalate mono(diethylene glycol monoisotridecyl ether) phthalate, methyltetrahydrophthalate mono(diethylene glycol monobenzyl ether) phthalate, methyltetrahydrophthalate mono(diethylene glycol monononylphenol ether) phthalate, methyltetrahydrophthalate mono(diethylene glycol monododecylphenol ether) phthalate, methyltetrahydrophthalate mono(diethylene glycol monooleyl ether) phthalate;

[0092] Methyltetrahydrophthalic acid mono(dipropylene glycol monomethyl ether), methyltetrahydrophthalic acid mono(dipropylene glycol monoethyl ether), methyltetrahydrophthalic acid mono(dipropylene glycol monopropyl ether), methyltetrahydrophthalic acid mono(dipropylene glycol monobutyl ether), methyltetrahydrophthalic acid mono(dipropylene glycol monoisobutyl ether), methyltetrahydrophthalic acid mono(dipropylene glycol monotert-butyl ether), methyltetrahydrophthalic acid mono(dipropylene glycol monopentyl ether), methyltetrahydrophthalic acid mono(dipropylene glycol monohexyl ether), methyltetrahydrophthalic acid mono(dipropylene glycol monooctyl ether), methyltetrahydrophthalic acid mono(dipropylene glycol monoiso ... Mono(dipropylene glycol monononyl ether) ester, methyltetrahydrophthalic acid mono(dipropylene glycol monoisononyl ether) ester, methyltetrahydrophthalic acid mono(dipropylene glycol monodecyl ether) ester, methyltetrahydrophthalic acid mono(dipropylene glycol monoisoundecyl ether) ester, methyltetrahydrophthalic acid mono(dipropylene glycol monolaurate ether) ester, methyltetrahydrophthalic acid mono(dipropylene glycol monoisotridecyl ether) ester, methyltetrahydrophthalic acid mono(dipropylene glycol monobenzyl ether) ester, methyltetrahydrophthalic acid mono(dipropylene glycol monononylphenol ether) ester, methyltetrahydrophthalic acid mono(dipropylene glycol monododecylphenol ether) ester, methyltetrahydrophthalic acid mono(dipropylene glycol monooleyl ether) ester, etc.;

[0093] Methylhexyl phthalate mono(diethylene glycol monomethyl ether), methylhexyl phthalate mono(diethylene glycol monoethyl ether), methylhexyl phthalate mono(diethylene glycol monopropyl ether), methylhexyl phthalate mono(diethylene glycol monobutyl ether), methylhexyl phthalate mono(diethylene glycol monoisobutyl ether), methylhexyl phthalate mono(diethylene glycol monotert-butyl ether), methylhexyl phthalate mono(diethylene glycol monopentyl ether), methylhexyl phthalate mono(diethylene glycol monooctyl ether), methylhexyl phthalate mono(diethylene glycol monoiso ... Mono(diethylene glycol monononyl ether) phthalate, methyl hexahydrophthalate mono(diethylene glycol monoisononyl ether) phthalate, methyl hexahydrophthalate mono(diethylene glycol monodecyl ether) phthalate, methyl hexahydrophthalate mono(diethylene glycol monoisoundecyl ether) phthalate, methyl hexahydrophthalate mono(diethylene glycol monolauryl ether) phthalate, methyl hexahydrophthalate mono(diethylene glycol monoisotridecyl ether) phthalate, methyl hexahydrophthalate mono(diethylene glycol monobenzyl ether) phthalate, methyl hexahydrophthalate mono(diethylene glycol monononylphenol ether) phthalate, methyl hexahydrophthalate mono(diethylene glycol monododecylphenol ether) phthalate, methyl hexahydrophthalate mono(diethylene glycol monooleyl ether) phthalate;

[0094] Methylhexyl phthalate mono(dipropylene glycol monomethyl ether), methylhexyl phthalate mono(dipropylene glycol monoethyl ether), methylhexyl phthalate mono(dipropylene glycol monopropyl ether), methylhexyl phthalate mono(dipropylene glycol monobutyl ether), methylhexyl phthalate mono(dipropylene glycol monoisobutyl ether), methylhexyl phthalate mono(dipropylene glycol monotert-butyl ether), methylhexyl phthalate mono(dipropylene glycol monopentyl ether), methylhexyl phthalate mono(dipropylene glycol monooctyl ether), methylhexyl phthalate mono(dipropylene glycol monoiso ... Mono(dipropylene glycol monononyl ether) ester, methyl hexahydrophthalic acid mono(dipropylene glycol monoisononyl ether) ester, methyl hexahydrophthalic acid mono(dipropylene glycol monodecyl ether) ester, methyl hexahydrophthalic acid mono(dipropylene glycol monoisoundecyl ether) ester, methyl hexahydrophthalic acid mono(dipropylene glycol monolaurate ether) ester, methyl hexahydrophthalic acid mono(dipropylene glycol monoisotridecyl ether) ester, methyl hexahydrophthalic acid mono(dipropylene glycol monobenzyl ether) ester, methyl hexahydrophthalic acid mono(dipropylene glycol monononylphenol ether) ester, methyl hexahydrophthalic acid mono(dipropylene glycol monododecylphenol ether) ester, methyl hexahydrophthalic acid mono(dipropylene glycol monooleyl ether) ester, etc.

[0095] The fuel lubricity improver of this application may contain appropriate amounts of fuel and / or organic solvents, as well as a small amount of unreacted raw materials, and inevitably contains some reaction byproducts, such as dicarboxylic acid diol ether esters.

[0096] In a second aspect, this application provides a method for preparing a fuel lubricity improver, comprising reacting a dicarboxylic acid having structural formula (II) or its anhydride with an alcohol ether or phenolic ether having structural formula (III).

[0097] (II)

[0098] (III)

[0099] The definitions and preferred embodiments of R1, R2, n, and R3 are as described in structural formula (I), namely:

[0100] R1 is a single bond, substituted or unsubstituted C 1-18 Divalent alkyl chain or C 2-6 The divalent alkenyl group, or a group having a -R4-R5-R6- structure, wherein R4 and R6 are each independently a single bond, or a substituted or unsubstituted C. 1-3 divalent alkyl, R5 is a substituted or unsubstituted C 3-12 The divalent alicyclic group; R2 is methylene, ethylene, or isopropylene; n is an integer from 1 to 12; R3 is a substituted or unsubstituted C1-40 Hydrocarbon group; wherein "substituted" means substituted by at least one C 1-4 Straight-chain or branched hydrocarbon group substitution.

[0101] In a preferred embodiment:

[0102] R1 is a single bond, substituted or unsubstituted C 2-8 Divalent alkyl chain or C 2-4 The divalent alkenyl group, or a group having a -R4-R5-R6- structure, wherein R4 and R6 are each independently a single bond or a methylene group; R5 is a substituted or unsubstituted C group. 3-8 The divalent alicyclic group; R2 is CH2, CH2CH2, CH(CH3)CH2, CH2CH(CH3); R3 is a substituted or unsubstituted C 1-18 Hydrocarbon group, preferably C 1-18 Straight-chain or branched hydrocarbon group, C 4-18 Alicyclic hydrocarbon groups, and C 7-18 The aryl-substituted hydrocarbon group or hydrocarbon-substituted aryl group is most preferably C1-18 alkyl or alkenyl; n is selected from an integer from 1 to 10, preferably from 1 to 6, and especially preferably from 1 to 3.

[0103] In a preferred embodiment, the reaction conditions include: the molar ratio of the dicarboxylic acid or anhydride to the alcohol ether or phenol ether is 1:0.5 to 1:1.5; the reaction temperature is 10-250°C; the reaction time is 0.1-10 hours; the reaction pressure can be atmospheric pressure or under a certain pressure; a catalyst can be used or not; and a solvent can be used or not.

[0104] In a further preferred embodiment, the reaction conditions include: the molar ratio of the dicarboxylic acid or anhydride to the alcohol ether or phenol ether is 1:0.8 to 1:1.3, the reaction temperature is 20-200°C, the reaction time is 1-6 hours, the reaction pressure can be atmospheric pressure, no catalyst is used, and no solvent is used.

[0105] In a preferred embodiment, the dicarboxylic acid or its anhydride having structural formula (II) includes, but is not limited to: maleic acid, maleic anhydride, fumaric acid, itaconic acid, itaconic anhydride, citraconic acid, citraconic anhydride, methyl fumaric acid, 2,3-dimethylmaleic acid, 2,3-dimethylmaleic anhydride, succinic acid, succinic anhydride, glutaric acid, glutaric anhydride, 1,2-cyclohexanedicarboxylic acid, tetrahydrophthalic acid, methyltetrahydrophthalic acid, methylhexahydrophthalic acid, 1,2-cyclohexanedicarboxylic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride (methyl-1,2-cyclohexanedicarboxylic anhydride), etc.

[0106] In a preferred embodiment, the alcohol ether having structural formula (III) may be methoxymethanol.

[0107] In a preferred embodiment, the alcohol ether or phenolic ether having structural formula (III) can be a reaction product of a fatty alcohol, alicyclic alcohol, aromatic alcohol or phenol with carbon numbers of C1-C30, preferably C1-C18, and ethylene oxide or propylene oxide, such as ethylene glycol monoalkyl ether, diethylene glycol monoalkyl ether, triethylene glycol monoalkyl ether, propylene glycol monoalkyl ether, dipropylene glycol monoalkyl ether, etc.

[0108] In a preferred embodiment, when n is 1, the alcohol ether or phenolic ether having structural formula (III) can be ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monoisobutyl ether, ethylene glycol monotert-butyl ether, ethylene glycol monopentyl ether, ethylene glycol monohexyl ether, ethylene glycol monoheptyl ether, ethylene glycol monooctyl ether, ethylene glycol monoisooctyl ether, ethylene glycol monononyl ether, ethylene glycol monoisononyl ether, ethylene glycol monodecyl ether, ethylene glycol monoisoundeether, ethylene glycol monolaurate ether, ethylene glycol monoisotridecyl ether, ethylene glycol monobenzyl ether, ethylene glycol monononylphenol ether, etc. Glycol monododecylphenol ether, ethylene glycol monooleyl alcohol ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, propylene glycol monoisobutyl ether, propylene glycol monotert-butyl ether, propylene glycol monopentyl ether, propylene glycol monohexyl ether, propylene glycol monoheptyl ether, propylene glycol monooctyl ether, propylene glycol monoisooctyl ether, propylene glycol monononyl ether, propylene glycol monoisononyl ether, propylene glycol monodecyl ether, propylene glycol monoisoundecid ether, propylene glycol monolaurate ether, propylene glycol monoisotridecyl ether, propylene glycol monobenzyl ether, propylene glycol monononylphenol ether, propylene glycol monododecylphenol ether, propylene glycol monooleyl alcohol ether, etc.

[0109] When n is 2, preferred specific examples include diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, diethylene glycol monoisobutyl ether, diethylene glycol monotert-butyl ether, diethylene glycol monopentyl ether, diethylene glycol monohexyl ether, diethylene glycol monooctyl ether, diethylene glycol monoisooctyl ether, diethylene glycol monononyl ether, diethylene glycol monoisononyl ether, diethylene glycol monodecyl ether, diethylene glycol monoisoundecyl ether, diethylene glycol monolaurate ether, diethylene glycol monoisotridecyl ether, diethylene glycol monobenzyl ether, diethylene glycol monononylphenol ether, diethylene glycol monododecylphenol ether, and diethylene glycol monomethyl ether. Dipropylene glycol monooleyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monobutyl ether, dipropylene glycol monoisobutyl ether, dipropylene glycol monotert-butyl ether, dipropylene glycol monopentyl ether, dipropylene glycol monohexyl ether, dipropylene glycol monooctyl ether, dipropylene glycol monoisooctyl ether, dipropylene glycol monononyl ether, dipropylene glycol monoisononyl ether, dipropylene glycol monodecyl ether, dipropylene glycol monoisoundecid ether, dipropylene glycol monolaurate ether, dipropylene glycol monoisotridecyl ether, dipropylene glycol monobenzyl ether, dipropylene glycol monononylphenol ether, dipropylene glycol monododecylphenol ether, dipropylene glycol monooleyl ether, etc.

[0110] When n is 3, preferred specific examples include triethylene glycol monoethyl ether, triethylene glycol monopropyl ether, triethylene glycol monobutyl ether, triethylene glycol monoisobutyl ether, triethylene glycol monotert-butyl ether, triethylene glycol monopentyl ether, triethylene glycol monohexyl ether, triethylene glycol monooctyl ether, triethylene glycol monoisooctyl ether, triethylene glycol monononyl ether, triethylene glycol monoisononyl ether, triethylene glycol monodecyl ether, triethylene glycol monoisoundecyl ether, triethylene glycol monolaurate ether, triethylene glycol monoisotridecyl ether, triethylene glycol monobenzyl ether, triethylene glycol monononylphenol ether, triethylene glycol monododecylphenol ether, and triethylene glycol monooil. Alcohol ethers, tripropylene glycol monomethyl ether, tripropylene glycol monoethyl ether, tripropylene glycol monopropyl ether, tripropylene glycol monobutyl ether, tripropylene glycol monoisobutyl ether, tripropylene glycol monotert-butyl ether, tripropylene glycol monopentyl ether, tripropylene glycol monohexyl ether, tripropylene glycol monooctyl ether, tripropylene glycol monoisooctyl ether, tripropylene glycol monononyl ether, tripropylene glycol monoisononyl ether, tripropylene glycol monodecyl ether, tripropylene glycol monoisoundecyl ether, tripropylene glycol monolaurate ether, tripropylene glycol monoisotridecyl ether, tripropylene glycol monobenzyl ether, tripropylene glycol monononylphenol ether, tripropylene glycol monododecylphenol ether, tripropylene glycol monooleyl alcohol ether, etc.

[0111] In the method of this application, a catalyst may or may not be added during the reaction. The catalyst can be an acid catalyst, such as one or more of sulfuric acid, hydrochloric acid, p-toluenesulfonic acid, phosphoric acid, boric acid, and acidic ion exchange resin; an ionic liquid catalyst, such as 1-butylpyridine / AlCl4 ionic liquid; an inorganic salt solid-phase catalyst, such as one or more of FeCl3 and AlCl3; a molecular sieve catalyst, such as one or more of ZSM-5, HZSM-5, and Al-MCM-41; a heteropolyacid catalyst, such as one or more of PW12 / MCM-41 and SiW12 / MCM-41; or a solid superacid catalyst, such as SO42-. 2- / ZrO2-TiO2、SO4 2- / TiO2-Al2O3, etc.; alkaline catalysts such as NaOH, KOH, sodium methoxide, solid superalkali, NaH, etc. can be used. A solvent may or may not be added during the reaction. The solvent can be hydrocarbons such as alkanes and aromatics, for example, petroleum ether, gasoline, toluene, xylene, etc.

[0112] According to this application, after the reaction is complete, the product after filtering to remove the catalyst (if a catalyst was used) can be used as the fuel lubricity improver of this application. Alternatively, the product can be separated and purified according to the anti-wear agent product standard requirements, such as removing solvents and unreacted raw materials. Solvents and unreacted raw materials that meet the standard requirements do not affect the anti-wear agent performance of this application, and these components, when added to fuel, have no adverse effect on fuel performance.

[0113] According to this application, an appropriate amount of fuel oil can be added to the reaction product to obtain a fuel oil anti-wear concentrate.

[0114] In a third aspect, this application provides a fuel composition comprising a fuel component and a fuel lubricity improver according to this application, wherein the content of the fuel lubricity improver is 5-400 ppm, preferably 10-300 ppm, based on 100% by mass of the fuel component.

[0115] In a preferred embodiment, the fuel component may be selected from diesel, gasoline and aviation fuel.

[0116] In some preferred embodiments, the fuel composition is a diesel composition comprising a diesel component and a fuel lubricity improver according to the present application, wherein the content of the dicarboxylic acid monool ether ester compound is 10-400 ppm, preferably 50-300 ppm, based on 100% by mass of the diesel component.

[0117] According to this application, the diesel fuel may include various low-sulfur diesel engine fuels. For example, it may be a fraction of crude oil (petroleum) processed by various refining processes in an oil refinery, such as atmospheric and vacuum distillation, catalytic cracking, catalytic reforming, coking, hydrorefining, and hydrocracking, with a distillation range between 160-380°C, and blended to meet the national standard GB 19147 for automotive diesel fuels.

[0118] The diesel fuel can also be second-generation biodiesel, which is derived from renewable resources such as vegetable oils and animal fats. It is typically produced in refineries using hydrotreating to hydrogenate vegetable oils, producing isomerized or non-isomerized long-chain hydrocarbons. Second-generation biodiesel may be similar in properties and quality to petroleum-based fuel oils.

[0119] The diesel fuel can be third-generation biodiesel, which is obtained by gasification and Fischer-Tropsch technology from non-oil biomass with high cellulose content, such as sawdust, crop straw and solid waste, and microbial oils.

[0120] The diesel fuel can also be coal liquefaction diesel (CTL), referring to diesel engine fuel obtained through coal-to-gas synthesis or direct coal liquefaction. It can also be a blended diesel fuel obtained by adding oxygenated diesel blending components to petroleum-based diesel fuel. These oxygenated diesel blending components are oxygenated compounds or mixtures of oxygenated compounds that can be blended with various diesel engine fuels to meet certain specifications; they are typically alcohols and ethers or mixtures thereof. Examples include ethanol and polyoxymethylene dimethyl ethers (PODEn, DMMn, or OME).

[0121] Depending on the application requirements, the diesel composition of this application may also contain one or more of the following additives: phenolic antioxidants, high molecular weight amine ashless dispersants, flow improvers, cetane number improvers, metal passivators, antistatic agents, corrosion inhibitors, rust inhibitors, and demulsifiers.

[0122] The high-molecular-weight amine-type ashless dispersant includes 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 hexadecane number improver can be a nitrate ester or a peroxide, such as isooctyl nitrate, di-tert-butyl peroxide, etc. The metal passivator can be an ammonium salt formed from benzotriazole and aliphatic amines, a product obtained by the Mannich reaction of benzotriazole, formaldehyde, and aliphatic amines, a Schiff base, and one or more organic polycarboxylic acids.

[0123] In some preferred embodiments, the fuel composition is an aviation fuel composition comprising aviation fuel components and a fuel lubricity improver according to the present application, wherein the content of the dicarboxylic acid monoester compound is 5-200 ppm, preferably 5-50 ppm, based on 100% by mass of the aviation fuel components.

[0124] In some preferred embodiments, the fuel composition is a gasoline composition comprising a gasoline component and a fuel lubricity improver according to the present application, wherein the content of the fuel lubricity improver is 5-400 ppm, preferably 10-300 ppm, based on 100% by mass of the gasoline component.

[0125] According to this application, the gasoline refers to refined petroleum fractions with a boiling range of 30-220℃, which may contain appropriate additives and are suitable as fuel for spark-ignition engines, including automotive gasoline and aviation piston engine fuel (also known as aviation gasoline). Automotive gasoline is mainly composed of catalytic cracking gasoline, reformed gasoline, aromatics, alkylated gasoline, and isomerized gasoline, and is classified into four grades according to research octane number: 89, 92, 95, and 98. The gasoline described in this application may also contain various oxygen-containing compounds such as methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), tert-amyl methyl ether (TAME), diisopropyl ether (DIPE), methanol, ethanol, and butanol. The gasoline described in this application can be automotive gasoline, automotive ethanol gasoline, and aviation gasoline that meet the requirements of GB 17930, GB 18351, and GB 1787.

[0126] Depending on the application requirements, the gasoline composition of this application may also contain one or more of the following additives: antioxidants, rust inhibitors, detergents and dispersants, and antiknock agents.

[0127] In a fourth aspect, this application provides a method for improving fuel lubricity, comprising adding a lubricity improver according to this application to fuel, wherein the amount of the fuel lubricity improver is 5-400 ppm, preferably 10-300 ppm, based on 100% of the mass of the fuel.

[0128] In some preferred embodiments, the method includes adding a lubricity improver according to the present application to low-sulfur diesel oil, wherein the amount of the fuel lubricity improver is 10-400 ppm, preferably 50-300 ppm, based on 100% by mass of the diesel oil.

[0129] In some preferred embodiments, the method includes adding a lubricity improver according to the present application to gasoline, wherein the amount of the fuel lubricity improver is 5-400 ppm, preferably 10-300 ppm, based on 100% by mass of the gasoline.

[0130] In a fifth aspect, this application provides the use of dicarboxylic acid monool ether ester compounds as fuel lubricity improvers, wherein the fuel lubricity improver has the following structural formula (I):

[0131] (I)

[0132] The definitions and preferred implementations of R1, R2, n, and R3 are as described above.

[0133] In a sixth aspect, this application provides a dicarboxylic acid monool ether ester compound suitable as a fuel lubricity improver, having the structure shown in formula (I):

[0134] (I)

[0135] Where R1 is a single bond, substituted or unsubstituted C 1-18 Divalent alkyl chain or C 2-6 The divalent alkenyl group, or a group having a -R4-R5-R6- structure, wherein R4 and R6 are each independently a single bond, or a substituted or unsubstituted C. 1-3 divalent alkyl, R5 is a substituted or unsubstituted C 3-12 The divalent alicyclic group; R2 is methylene, ethylene, or isopropylene; n is an integer from 1 to 12; R3 is a substituted or unsubstituted C 1-40 Hydrocarbon group.

[0136] In the preferred embodiment, in structure (I), R1 is a single bond, a substituted or unsubstituted C bond. 2-8 Divalent alkyl chain or C 2-4The divalent alkenyl group, or a group having a -R4-R5-R6- structure, where R4 and R6 are each independently a single bond or a methylene group, and R5 is a substituted or unsubstituted C- group. 3-8 The divalent alicyclic group; n is an integer from 1 to 6; R3 is a substituted or unsubstituted C 1-18 Hydrocarbon group.

[0137] In a preferred embodiment, the dicarboxylic acid monool ether ester compound is selected from: mono(ethylene glycol monobutyl ether) maleate, mono(ethylene glycol monoisopentyl ether) maleate, mono(ethylene glycol monoisooctyl ether) maleate, mono(diethylene glycol monobutyl ether) maleate, mono(ethylene glycol monobutyl ether) succinate, mono(ethylene glycol monomethyl ether) succinate, mono(ethylene glycol monoisooctyl ether) methylhexahydrophthalic acid mono(ethylene glycol monomethyl ether), mono(diethylene glycol monomethyl ether) methylhexahydrophthalic acid mono(diethylene glycol monoisooctyl ether) methylhexahydrophthalic acid mono(diethylene glycol monoisooctyl ether) ester.

[0138] The present application will be further described below through examples, but this does not limit the scope of the present application.

[0139] Example 1

[0140] Preparation of mono(ethylene glycol monobutyl ether) maleate:

[0141] In a 500 mL reactor equipped with an electric stirrer and a thermometer, 236 g of ethylene glycol monobutyl ether (99.5%, produced by Beijing Chemical Reagent Company) and 143 g of maleic anhydride (99.5%, produced by Aladdin Reagent Company) were added. The molar ratio of ethylene glycol monobutyl ether to maleic anhydride was approximately 1:1. The mixture was heated and stirred to 90 °C. After reacting for 5 hours, the unreacted raw material was distilled under reduced pressure to obtain 362 g of product with maleic acid mono(ethylene glycol monobutyl ether) ester as the main product. The product had a freezing point of -43 °C.

[0142] Example 2

[0143] Preparation of maleic acid mono(diethylene glycol monobutyl ether) ester:

[0144] In a 500 mL reactor equipped with an electric stirrer and a thermometer, 162 g of diethylene glycol monobutyl ether (99%, purchased from Beijing Innocare Technology Co., Ltd.) and 108 g of maleic anhydride (99.5%, produced by Aladdin Reagent Co., Ltd.) were added. The molar ratio of diethylene glycol monobutyl ether to maleic anhydride was approximately 1:1.1. The mixture was heated and stirred until the temperature reached 105 °C. After reacting for 5 hours, the unreacted raw material was distilled under reduced pressure to obtain 252.7 g of product with maleic acid mono(diethylene glycol monobutyl ether) ester as the main product. The product had a freezing point of -41 °C.

[0145] Example 3

[0146] Preparation of mono(ethylene glycol monoisooctyl ether) maleate:

[0147] In a 250 mL reactor equipped with an electric stirrer and a thermometer, 76.5 g of ethylene glycol monoisooctyl ether (98%, manufactured by Maclean's Reagent Company) and 39.2 g of maleic anhydride (99.5% by mass, manufactured by Aladdin Reagent Company) were added. The molar ratio of ethylene glycol monoisooctyl ether to maleic anhydride was approximately 1.1:1. The mixture was heated and stirred to 95 °C. After reacting for 4 hours, the unreacted raw material was distilled under reduced pressure to obtain 103.8 g of product with maleic acid mono(ethylene glycol monoisooctyl ether) ester as the main product. The product had a freezing point of -36 °C.

[0148] Under the same conditions, maleic acid monodecyl ester was obtained by reacting decyl alcohol, which has the same number of carbons as ethylene glycol monoisooctyl ether, with a freezing point greater than 20°C.

[0149] Example 4

[0150] Preparation of mono(propylene glycol monobutyl ether) succinate:

[0151] In a 250 mL reactor equipped with an electric stirrer and a thermometer, 66.0 g of propylene glycol monobutyl ether (98%, produced by Aladdin Reagent Company), 39.2 g of succinic anhydride (99% by mass, produced by Aladdin Reagent Company), 3 g of triethylamine (analytical grade reagent, produced by Maclean's Reagent Company), and 110 mL of petroleum ether (90-120, Sinopharm Group Reagent) were added. The molar ratio of propylene glycol monobutyl ether to succinic anhydride was approximately 1:1.1. The mixture was heated and stirred to 70 °C, and after reacting for 4 hours, it was placed in a -18 °C freezer for 24 hours. The supernatant was collected and distilled under reduced pressure to remove petroleum ether and triethylamine, yielding 90.8 g of product with propylene glycol monobutyl ether as the main product. The product had a freezing point of -26 °C.

[0152] Under the same conditions, heptanol with the same number of carbon atoms as propylene glycol monobutyl ether was reacted to obtain heptanoic acid monoheptyl ester, and the product had a freezing point greater than 0℃.

[0153] Example 5

[0154] Preparation of methylhexahydrophthalic acid mono(diethylene glycol monoisooctyl ether) ester:

[0155] In a 150 mL reactor equipped with an electric stirrer and a thermometer, 43.6 g of diethylene glycol monoisooctyl ether (98%) and 27.6 g of methylhexahydrophthalic anhydride (95%, manufactured by Aladdin Reagent Company) were added. The molar ratio of diethylene glycol monoisooctyl ether to methylhexahydrophthalic anhydride was approximately 1:1. The mixture was heated and stirred to 120 °C. After reacting for 5 hours, 70.1 g of product with methylhexahydrophthalic acid mono(diethylene glycol monoisooctyl ether) ester as the main product was obtained. The product had a freezing point of -45 °C.

[0156] Under the same conditions, dodecanol with the same number of carbon atoms as diethylene glycol monoisooctyl ether was reacted to give methyl hexahydrophthalic acid monododecyl ester, and the product had a freezing point greater than 10°C.

[0157] Example 6

[0158] Preparation of methyl hexahydrophthalic acid mono(diethylene glycol monomethyl ether) ester:

[0159] In a 250 mL reactor equipped with an electric stirrer and a thermometer, 48.0 g of diethylene glycol monomethyl ether (99%) and 70.7 g of methylhexahydrophthalic anhydride (95%, produced by Aladdin Reagent Company) were added. The molar ratio of diethylene glycol monomethyl ether to methylhexahydrophthalic anhydride was approximately 1:1. The mixture was heated and stirred to 60 °C. After reacting for 5 hours, 115 g of product with methylhexahydrophthalic acid mono(diethylene glycol monomethyl ether) ester as the main product was obtained. The product had a freezing point of -42 °C.

[0160] Comparative Example 1

[0161] In a 500 mL reactor equipped with an electric stirrer and a thermometer, 204 g of n-hexanol (99.5%, produced by Beijing Chemical Reagent Company) and 196 g of maleic anhydride (99.5%, produced by Aladdin Reagent Company) were added. The molar ratio of n-hexanol to maleic anhydride was approximately 1:1. The mixture was heated and stirred until it reached 90 °C. After reacting for 5 hours, the unreacted raw material was distilled under reduced pressure to obtain 361 g of product with mono-n-hexyl maleate as the main product. The product had a freezing point of -19 °C.

[0162] Comparative Example 2

[0163] In a 500 mL reactor equipped with an electric stirrer and a thermometer, 195.0 g of n-octanol (99%, purchased from Beijing Innocare Technology Co., Ltd.) and 161.7 g of maleic anhydride (99.5%, produced by Aladdin Reagent Co., Ltd.) were added. The molar ratio of n-octanol to maleic anhydride was approximately 1.1:1. The mixture was heated and stirred until the temperature reached 105 °C. After reacting for 5 hours, the unreacted raw material was distilled under reduced pressure to obtain 339.9 g of product with mono-n-octyl maleate as the main product. The product had a freezing point of 11 °C.

[0164] Test Example 1

[0165] This test case demonstrates the effect of diesel anti-wear agent in diesel fuel as used in the examples and comparative examples. Diesel fuel A was sourced from Sinopec Yanshan Branch, and its physicochemical properties are shown in Table 1.

[0166] Table 1 Basic Physicochemical Properties of Diesel Oil

[0167] project Analysis results <![CDATA[Density (20 °C) / (kg·m -3 )]]> 821.2 Initial boiling point / °C 174.9 5% temperature / ℃ 206.8 10% temperature / ℃ 216.6 30% temperature / ℃ 237.8 50% temperature / ℃ 254.3 70% temperature / ℃ 272.2 90% temperature / ℃ 314.0 95% temperature / ℃ 335.7 Final boiling point / °C 348.2 Residual amount (ψ) / % 1.4 Loss (ψ) / % 0.7 Monocyclic aromatic hydrocarbons (w) / % 17.1 Bicyclic aromatic hydrocarbons (w)% 1.0 Tricyclic + Aromatic Hydrocarbons (w)% 0.1 Polycyclic aromatic hydrocarbons (w)% 1.1 Total aromatics (w) / % 18.2 <![CDATA[Viscosity at 20 °C / (mm 2 ·s -1 )]]> 3.629 <![CDATA[Acidity / (mgKOH·100mL -1 ) -1 )]]> <0.20 10% of the distillation residue and charcoal, % <0.05 Ash content, % <0.002 Cold filter plugging point / °C -11 Freezing point / °C -20 Closed-cup flash point / ℃ 70 <![CDATA[w (sulfur) / mg·L -1 > 7.3 <![CDATA[Oxidation stability, total insolubles / (mg·100mL -1 )]]> <0.3 Moisture, % trace Lubricity (HFRR) / μm 648

[0168] The lubricity of diesel fuel was determined according to the SH / T 0765 method on a high-frequency reciprocating tester (High-Frequency Reciprocating Rig, HFRR, PCS Instruments, UK) at 60°C. The results were reported as WS1.4 after correction for the effects of temperature and humidity.

[0169] Table 2 shows the wear scar diameter (WS1.4) of diesel fuel before and after additive addition. A smaller wear scar diameter indicates better diesel fuel lubricity. Currently, most diesel fuel standards worldwide, such as European standard EN 590, Chinese automotive diesel fuel standard GB 19147, and Beijing municipal standard DB 11 / 239, use a wear scar diameter of less than 460 μm (60℃) as the criterion for acceptable diesel fuel lubricity.

[0170] As shown in Table 2, the additive provided by this invention has a surprisingly good effect on improving the lubricity of diesel fuel. At the same dosage, it is significantly better than the existing industrial product Hitec 4140, while the reaction raw materials ethylene glycol monobutyl ether and diethylene glycol monobutyl ether have no effect on improving the lubricity of diesel fuel. Specifically, comparing Example 1 and Comparative Example 1, Example 1 uses the same synthesis conditions and has the same number of carbon atoms as Comparative Example 1. The difference is that Example 1 uses ethylene glycol monobutyl ether (alcohol ether) for esterification, resulting in an additional oxygen atom in its structural formula compared to Comparative Example 1. As shown in Table 2, at the same dosage, Example 1 is more effective than Comparative Example 1. Furthermore, the pour point of the product of Example 1 is below -40°C, while the pour point of the product of Comparative Example 1 is above -30°C. Example 1 is more suitable for improving the lubricity of ultra-low pour point diesel fuel with a pour point below -50°C, ensuring its safe use in extremely cold and harsh environments. Example 2 has the same number of carbon atoms in its structural formula as Comparative Example 2 but has two more oxygen atoms, resulting in better anti-wear performance. The pour point of the product in Example 2 is below -40°C, while the pour point of the product in Comparative Example 2 is above 10°C. The pour point of Example 2 is 50°C lower than that of Comparative Example 2. Example 2 is more suitable for ultra-low pour point diesel oil with a pour point below -50°C or even -70°C to improve its lubricity, while ensuring that the anti-wear agent in ultra-low pour point diesel oil does not solidify and precipitate in extremely cold and harsh environments.

[0171] Table 2 Evaluation of the lubricating performance of diesel fuel with additives

[0172] oil sample <![CDATA[Added dose (mg•kg -1 ).]]> WS1.4 (μm) Diesel A / 648 Diesel A+ Example 1 Product 150 227 Diesel A+ Comparative Example 1 Product 150 274 Diesel A+ Example 1 Product 120 325 Diesel A+ Comparative Example 1 Product 120 356 Diesel A + Ethylene Glycol Monobutyl Ether 150 651 Diesel A+ Example 2 Product 150 216 Diesel A+ Comparative Example 2 Product 150 266 Diesel A+ Example 2 Product 120 281 Diesel A+ Comparative Example 2 Product 120 350 Diesel A + Diethylene Glycol Monobutyl Ether 150 637 Diesel A+ Example 3 Product 120 256 Diesel A+ Example 4 Product 120 325 Diesel A+ Example 5 Product 120 371 Diesel A+ Example 6 Product 120 365 Diesel A+ Hitec 4140 150 456

[0173] Note: Hitec 4140 is a commonly used diesel anti-wear additive in industry, and its main component is octadecyl unsaturated fatty acid.

[0174] Test Example 2

[0175] The test examples demonstrate the effectiveness of the gasoline anti-wear agent in the embodiments and the existing industrial anti-wear agent in the comparative examples in gasoline. The physicochemical properties of the 95-octane gasoline used are shown in Table 3.

[0176] Table 3. Physicochemical properties of 95-octane gasoline

[0177] project 95-octane gasoline Research Octane Number (RON) 96.0 Motor Octane Number (MON) 86.6 Aromatics volume fraction / % 25.8 Olefin volume fraction / % 6.8 Saturated hydrocarbon volume fraction / % 67.4 Vapor pressure (RVPE) / kPa 54.1 Net calorific value (MJ / kg) 42.25 Distillation range, initial boiling point T10, T20, T30, T40, T50, T60, T70, T80, T90, T95; final boiling point 25.7356.968.1179.191.47104.22115.23124.5136.64156.52171.24193.52 Residual amount / % (φ) 0.5 Loss amount / % (φ) 2 <![CDATA[Density at 20 °C / (kg / m 3 )]]> 739.5 <![CDATA[Density at 15°C / (kg / m 3 )]]> 743.6 Carbon content / % (w) 86.43 Hydrogen content / % (w) 13.57 (Unwashed) gelatinous substance / (mg / 100mL) 13.1 (After washing) Gel content / (mg / 100mL) <0.5 Benzene content / % (w) 0.3 Toluene / %(w) 6.95 Ethanol / %(w) 0 MTBE / %(w) 6.16 Thiol sulfur (mg / kg) < 3 Water-soluble acids or bases none Copper sheet corrosion (50℃, 3h) / grade 1a Fe content (mg / kg) <1 Pb content (mg / kg) <1 P content (mg / kg) <1 Si content (mg / kg) <1 Mn content (mg / kg) <1 Chlorine content (mg / L) 0.65 Water content (mg / L) 76 Sulfur content (mg / L) 4.5 Induction period / min >1000 Nitrogen content (mg / L) 11 <![CDATA[Diene value / (gI2 / 100g)]]> 1.2

[0178] The wear scar diameter (WSD) of gasoline at 25°C was measured on a high-frequency reciprocating rig (HFRR, PCS Instruments, UK). The smaller the wear scar diameter, the better the gasoline lubricity or the better the anti-wear agent effect. The results are shown in Table 4.

[0179] Table 4. Evaluation of the lubricity of gasoline samples

[0180] Serial Number oil sample <![CDATA[Additional dose / (mg•kg -1 ).]]> WSD / (μm) 1 95-octane gasoline / 843 2 95-octane automotive gasoline + Example 1 product 200 327 3 95-octane automotive gasoline + Comparative Example 1 200 378 4 95-octane automotive gasoline + Example 2 product 200 340.5 5 95-octane automotive gasoline + Comparative Example 2 200 389

[0181] As shown in Table 4, the wear scar diameter of blank 95-octane gasoline at 25°C measured by the HFRR tester was as high as 843 μm. The addition of the dicarboxylic acid monool ether ester compound described in this invention can greatly improve the lubricity of gasoline. In Example 1, the lubricity wear scar diameter of blank 95-octane gasoline was reduced to 327 μm at an addition amount of 200 mg / kg, while in Comparative Example 1 it was reduced to 378 μm at 200 mg / kg. The effect of the Example 1 is better than that of the Comparative Example.

Claims

1. A fuel composition comprising fuel and a lubrication improver, said lubrication improver comprising a dicarboxylic acid monool ether ester compound represented by structural formula (I): （I） in, R1 is a single bond, substituted or unsubstituted C 1-18 Divalent alkyl chain or C 2-6 A divalent alkenyl group, or a group having a -R4-R5-R6- structure, where R4 and R6 are each independently a single bond, substituted or unsubstituted C. 1-3 divalent alkyl, R5 is a substituted or unsubstituted C 3-12 The divalent alicyclic group; R2 is methylene, ethylene, or isopropylene; n is an integer from 1 to 3; R3 is a substituted or unsubstituted C 1-18 Hydrocarbon group; the content of the dicarboxylic acid monool ether ester compound is 5-400 ppm based on 100% mass of the fuel.

2. The fuel composition according to claim 1, wherein, In structural formula (I), R1 is a single bond, substituted or unsubstituted C. 2-8 Divalent alkyl chain or C 2-4 The divalent alkenyl group, or a group having a -R4-R5-R6- structure, where R4 and R6 are each independently a single bond or a methylene group, and R5 is a substituted or unsubstituted C- group. 3-8 The divalent alicyclic group; n is an integer from 1 to 3; R3 is a substituted or unsubstituted C 1-12 Hydrocarbon group.

3. The fuel composition according to claim 1, wherein, The dicarboxylic acid monool ether ester compound is selected from maleic acid monool ether ester, fumarate monool ether ester, itaconic acid monool ether ester, methyl maleic acid monool ether ester, methyl fumarate monool ether ester, 2,3-dimethyl maleic acid monool ether ester, ethyl maleic acid monool ether ester, pentenediaic acid monool ether ester, succinic acid monool ether ester, glutaric acid monool ether ester, or any combination thereof.

4. The fuel composition according to claim 1, wherein, The dicarboxylic acid monool ether ester compound is selected from 1,2-cyclopentadicarboxylic acid monool ether ester, 1,2-cyclohexanedicarboxylic acid monool ether ester, tetrahydrophthalic acid monool ether ester, phthalic acid monool ether ester, methylhexahydrophthalic acid monool ether ester, and methyltetrahydrophthalic acid monool ether ester.

5. The fuel composition according to claim 1, wherein, The dicarboxylic acid monool ether ester compound is selected from one or more of the following: ethylene glycol monobutyl ether maleate, ethylene glycol monoisopentyl ether maleate, ethylene glycol monoisooctyl ether maleate, diethylene glycol monobutyl ether maleate, ethylene glycol monobutyl ether succinate, ethylene glycol monomethyl ether succinate, ethylene glycol monoisooctyl ether succinate, methyl hexahydrophthalic acid monomethyl ether, methyl hexahydrophthalic acid monomethyl ether, and methyl hexahydrophthalic acid monoisooctyl ether.

6. The fuel composition according to claim 1, wherein the content of the dicarboxylic acid monool ether ester compound is 10-300 ppm based on 100% by mass of the fuel.

7. The fuel composition according to claim 1, wherein, The fuel is selected from one or more of diesel, gasoline and aviation fuel.

8. The fuel composition according to claim 7, wherein, The diesel fuel is selected from low-sulfur diesel engine fuel.

9. The fuel composition according to claim 7, wherein, The diesel fuel is selected from one or more of second-generation biodiesel, third-generation biodiesel, and coal liquefaction diesel.

10. Use of dicarboxylic acid monool ether ester compounds as fuel lubricity improvers, wherein the dicarboxylic acid monool ether ester compound is shown in structural formula (I): (I) in, R1 is a single bond, substituted or unsubstituted C 1-18 Divalent alkyl chain or C 2-6 A divalent alkenyl group, or a group having a -R4-R5-R6- structure, where R4 and R6 are each independently a single bond, substituted or unsubstituted C. 1-3 divalent alkyl, R5 is a substituted or unsubstituted C 3-12 The divalent alicyclic group; R2 is methylene, ethylene, or isopropylene; n is an integer from 1 to 3; R3 is a substituted or unsubstituted C 1-18 Hydrocarbon group.

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