CN107794097B

CN107794097B - Low-acid type diesel oil multi-effect additive and diesel oil composition

Info

Publication number: CN107794097B
Application number: CN201610793427.0A
Authority: CN
Inventors: 王祥; 张建荣; 李妍; 蔺建民
Original assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Current assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Priority date: 2016-08-31
Filing date: 2016-08-31
Publication date: 2020-08-18
Anticipated expiration: 2036-08-31
Also published as: CN107794097A

Abstract

The invention relates to a low-acid diesel multi-effect additive composition which comprises a) hydrocarbyl-substituted succinyl hydrazide and b) fatty acid polyol ester, wherein the weight ratio of a to b is 1: 0.1-20. The additive of the present invention has high antiwear effect, high rust resistance and less influence on the acidity of diesel oil.

Description

Low-acid type diesel oil multi-effect additive and diesel oil composition

Technical Field

The present invention relates to diesel oil composition, and is especially one kind of multi-effect diesel oil additive composition and diesel oil composition.

Background

With the increasing attention of countries in the world to the environmental protection problem, the production of high-quality clean diesel oil for reducing the diesel oil exhaust pollution has become the development direction of the modern oil refining industry. The diesel oil generally has the characteristics of low sulfur content, low aromatic hydrocarbon content, high cetane number, light fraction and the like. Research shows that sulfur is the most harmful element for increasing CH and CO in diesel engine emissions, especially inhalable Particulate Matters (PM), so that the reduction of the sulfur content in diesel is particularly important for improving atmospheric pollution. At present, the diesel oil specifications of the United states, Canada and Western Europe all stipulate that the S content of the diesel oil is less than 0.05 percent, and some countries even reach less than 0.0015 percent; the aromatic content is also low. Because the diesel oil and the diesel oil are generally subjected to a harsher hydrogenation process, the content of polar oxygen-containing and nitrogen-containing compounds in the diesel oil is low, and the content of polycyclic and bicyclic aromatic hydrocarbons is low, so that the natural lubricating performance of the diesel oil is reduced, and the abrasion of oil injection pumps (such as rotary pumps) and distribution pumps (distributor pumps) which rely on the diesel oil to lubricate are caused, so that the service life of the oil injection pumps is shortened.

The above problems can be alleviated by adding additives to the diesel fuel. It is believed that the diesel antiwear agent can compensate the loss of lubricating components in oil caused by hydrotreating diesel oil, and improve the lubricity of diesel oil.

The fatty acid antiwear agent used for jet fuel, such as dimer acid type acid additive, can not be applied to diesel oil due to poor compounding performance with lubricating oil, so that the diesel oil antiwear agent is mostly a derivative of fatty acid ester, amide or salt. US588236 discloses carboxylic acid esters prepared by reacting monocarboxylic acids having an unsaturated chain with a polyol as diesel antiwear agents. U.S. Pat. No. 4,983,99b discloses the use of branched succinic anhydrides or acids, C₁～C₅The mixed mixture of the monohydric alcohol and the nitrate can be used as a diesel additive to improve the lubricity and the ignition performance of the diesel. CN1766067 discloses a product obtained by reacting polyolefin succinic anhydride with one or more of polyol, polyamine and amino alcohol as a diesel antiwear agent. WO9915607 discloses the reaction product of a dimerised fatty acid with an epoxide as a diesel antiwear agent.

With the gradual reduction of the sulfur content in the diesel oil standard, the rust-proof components in the diesel oil are removed along with the increase of the hydrogenation depth, so the problem of the rust resistance of the diesel oil is more and more obvious. Rusted metal surfaces tend to appear specks, and rusted products can block filters and sometimes even clamp precision parts such as valves, sleeves, pistons and the like, so that the normal operation of a fuel system is damaged. The acid value of the existing industrial rust inhibitor such as T746 is too high, and the addition of the prior industrial rust inhibitor into diesel oil can cause the increase of the acidity of the oil product.

Disclosure of Invention

The invention aims to provide a low-acid multi-effect additive composition capable of improving the anti-wear and anti-rust capability of low-sulfur diesel based on the prior art.

The invention also provides a low-sulfur diesel oil composition with good anti-wear and anti-rusting capabilities.

The invention also provides a method for improving the wear resistance and rust resistance of the low-sulfur diesel.

The invention provides a low-sulfur diesel multi-effect additive composition, which comprises the following components: a) hydrocarbyl-substituted succinylhydrazide; b) C8-C24 fatty acid polyol ester, wherein the weight ratio of a to b is 1: 0.1-20, preferably 1: 0.5-10, more preferably 1:1 to 6.

The hydrocarbyl-substituted succinylhydrazide has the general formula:

wherein at least one of R1, R2, R3 and R4 is a hydrocarbon group containing 1-50 carbons or a hydrocarbon group containing other hetero atoms, and the rest is hydrogen. The hydrocarbyl is preferably C8-C18 alkenyl, the number of double bonds is 1-3, and the hydrocarbyl can be derived from C₂～C₄Copolymers or homopolymers of monoolefins, such as polyisobutylene, atactic polypropylene or ethylene-propylene copolymers. R5 and R6 are selected from hydrogen or alkyl containing 1-20 carbon atoms or alkyl containing other heteroatom groups, preferably hydrogen and methyl, ethyl, allyl, phenyl, benzyl, tert-butyl and the like. Among the preferred hydrocarbyl-substituted succinylhydrazides are: undecenylsuccinylhydrazide, dodecenylsuccinylhydrazide, tridecenylsuccinylhydrazide, tetradecenylsuccinylhydrazide, pentadecenylsuccinylhydrazide, hexadecenylsuccinylhydrazide, heptadecenylsuccinylhydrazide, octadecenylsuccinylhydrazide, undecenylsuccinylhydrazide, dodecenylsuccinylhydrazide, tridecenylsuccinylhydrazide, tetradecenylsuccinylhydrazide, pentadecenylsuccinylhydrazide, hexadecenylsuccinylhydrazide, heptadecenylsuccinylhydrazide, octadecenylsuccinylhydrazide and the like.

The hydrocarbyl-substituted succinyl hydrazide is prepared by reacting hydrocarbyl-substituted succinic anhydride with hydrazine, the reaction temperature is 0-200 ℃, preferably 80-150 ℃, and the reaction time is 1-36 hours, preferably 5-10 hours. The molar ratio of the hydrocarbyl-substituted succinic anhydride (calculated as maleic anhydride) to hydrazine is 1: 0.5-10, preferably 1: 0.8-1.5.

The reaction is carried out in a normal pressure container, the reaction can be carried out without adding a catalyst or adding a proper catalyst to accelerate the reaction, and an acidic or basic catalyst can be added according to the nature of the reaction. Acidic catalysts such as sulfuric acid, p-toluenesulfonic acid, hydrochloric acid, acidic ion exchange resins, solid superacids and the like, and basic catalysts such as sodium hydroxide, sodium methoxide and the like. The reaction can be carried out by refluxing the solvent for water separation or by blowing nitrogen for water removal. The solvent can be toluene, xylene, ethylbenzene, n-hexane, cyclohexane, petroleum ether, solvent gasoline, ethanol, isopropanol, n-butanol, etc., and can also be aromatic hydrocarbon diluent oil with distillation range of 159-185 ℃.

The general structural formula of the hydrocarbyl-substituted succinic anhydride is as follows:

wherein at least one of R1, R2, R3 and R4 is a hydrocarbon group containing 1-50 carbons or a hydrocarbon group containing other hetero atoms, and the rest is hydrogen. The hydrocarbyl is preferably C8-C18 alkenyl, the number of double bonds is 1-3, and the hydrocarbyl can be derived from C₂～C₄Copolymers or homopolymers of monoolefins, such as polyisobutylene, atactic polypropylene or ethylene-propylene copolymers.

The hydrazine is selected from hydrazine, hydrazine hydrate aqueous solution or C1-C20 alkyl hydrazine, and the general formula is as follows:

wherein R5 and R6 are selected from hydrogen or alkyl containing 1-20 carbon atoms or alkyl containing other heteroatom groups, such as methylhydrazine, unsym-dimethylhydrazine, ethylhydrazine, allyl hydrazine, phenylhydrazine, benzylhydrazine, tert-butylhydrazine, 1- (4-morpholinylbutyl) hydrazine, cyclopentylhydrazine, cyclohexylhydrazine, CAS: 15888-12-7, etc.

The component b is C8-C24 fatty acid polyol ester. The fatty acid polyol ester can be a transesterification reaction product of natural oil and polyol, an esterification reaction product of C8-C24 fatty acid and polyol, or a reaction product or a product mixture of fatty acid methyl ester (biodiesel) and polyol.

The polyhydric alcohol is an alcohol containing at least two hydroxyl groups in the molecule, and is preferably a C2-C8 polyhydric alcohol. Such as ethylene glycol, polyethylene glycol, glycerol, various isomers of propylene glycol, butylene glycol, pentylene glycol, hexylene glycol, heptylene glycol, octylene glycol, nonylene glycol, decylene glycol, and pentaerythritol, sorbitol, sorbitan, trimethylolpropane, etc.

The natural oil is vegetable oil or animal oil, and can be fresh oil or recovered waste oil. Wherein the vegetable oil is selected from peanut oil, corn oil, cotton seed oil, rapeseed oil, soybean oil, palm oil, safflower oil, linseed oil, coconut oil, oak oil, almond oil, walnut oil, linseed oil, sesame oil, olive oil, sunflower seed oil and the like, the animal oil is selected from lard, chicken oil, duck oil, mutton fat, beef tallow, whale oil, fish oil and the like, and the vegetable oil is preferred.

In the reaction product of natural oil and polyol, one triglyceride molecule may react with one, two or three hydroxyl groups to form ester.

Since natural oils and fats are mixed glycerides mainly containing octadecane, the molecular weight of the natural oils and fats can be roughly regarded as the same as that of tristearin (molecular weight of 890) for the convenience of calculating the feed ratio. The reaction can be catalyzed by acid such as sulfuric acid, p-toluenesulfonic acid, acidic ion exchange resins, Lewis acids, etc., or by base such as sodium hydroxide, potassium hydroxide, dimethylcyclohexylamine, etc. The reaction time is 1 to 20 hours, preferably 2 to 10 hours. The reaction temperature is 50-300 ℃, preferably 80-260 ℃.

When the fatty acid is esterified with a polyhydric alcohol, the fatty acid may be selected from C8 to C24 fatty acids, such as caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, arachidic acid, behenic acid, erucic acid, etc., preferably oleic acid and linoleic acid. Or a mixture of acids, such as animal or vegetable oleic acid, for example lard, chicken oil, duck oil, goose oil, mutton oil, horse oil, beef tallow, rabbit oil, whale oil, shark oil fatty acids; peanut oil, corn oil, cottonseed oil, rapeseed oil, soybean oil, palm oil, safflower oil, linseed oil, coconut oil, oak oil, almond oil, walnut oil, castor oil, sesame oil, olive oil, sunflower oil, jatropha oil, tung oil, xanthoceras sorbifolia oil, fatty acids of oils and fats of saline soil plants such as seashore mallow, cyperus esculentus and the like, tall oil fatty acids extracted from paper waste, preferably refined tall oil fatty acids from which rosin acids have been removed, such as the tall oil fatty acid sold under the designation 2LT by Arizonal corporation, usa. The reaction molar ratio of the fatty acid to the fatty alcohol is 1:0.1 to 10, preferably 1: 0.5-5 ℃, the reaction temperature is 50-300 ℃, and the optimal temperature is 80-260 ℃. The reaction can be carried out without a catalyst, or by acid catalysis such as sulfuric acid, p-toluenesulfonic acid, acidic ion exchange resins, Lewis acids and the like, or by base catalysis such as sodium hydroxide, potassium hydroxide, dimethylcyclohexylamine and the like. The reaction time is 1 to 20 hours, preferably 2 to 10 hours. The reaction may be carried out by blowing water with an inert gas such as nitrogen or by carrying water with a solvent.

The fatty acid methyl ester is a mixture of fatty acid methyl esters mainly containing C16-C20, such as methyl palmitate, methyl stearate, methyl oleate, methyl linoleate, methyl linolenate, methyl arachinate and methyl erucate. The reaction molar ratio of the fatty acid methyl ester to the polyol is 1:0.1 to 10, preferably 1: 0.5-5 ℃, the reaction temperature is 50-300 ℃, and the optimal temperature is 80-260 ℃. The reaction can be carried out without using a catalyst, can be catalyzed by acid such as sulfuric acid, p-toluenesulfonic acid, acidic ion exchange resin, Lewis acid and the like, and can be catalyzed by alkali such as sodium hydroxide, sodium methoxide, potassium hydroxide, dimethylcyclohexylamine and the like. The reaction time is 1 to 20 hours, preferably 2 to 10 hours. The reaction may be carried out by blowing methanol with an inert gas such as nitrogen or by carrying methanol produced by the reaction with a solvent.

According to the using requirement, the low-sulfur diesel multi-effect additive composition provided by the invention can also contain a solvent, wherein the solvent can be selected from toluene, xylene, ethylbenzene, n-hexane, cyclohexane, petroleum ether, solvent gasoline, methanol, ethanol, isopropanol, n-butanol and the like, and can also be aromatic hydrocarbon diluent oil with the distillation range of 159-185 ℃.

The low-sulfur diesel multi-effect additive composition provided by the invention can also contain other additives, such as a cetane number improver, a flow improver, a metal deactivator, a preservative and the like.

The low-sulfur diesel oil composition comprises low-sulfur diesel oil and the low-sulfur diesel oil multi-effect additive composition, wherein the content of the additive in the diesel oil is generally 10-500 mg/kg, preferably 50-300 mg/kg based on the weight of the low-sulfur diesel oil.

The sulfur content in the low-sulfur diesel oil is 0-100 mg/kg, particularly 0-50 mg/kg.

The low-sulfur diesel oil composition provided by the invention can also contain other additives such as cetane number improver, flow improver, metal deactivator, preservative and the like according to use requirements.

The method for improving the anti-wear and anti-rust capability of low-sulfur diesel oil is characterized in that the multi-effect additive composition of the low-sulfur diesel oil provided by the invention is added into the low-sulfur diesel oil, and the content of the additive in the diesel oil is generally 10-500 mg/kg, preferably 50-300 mg/kg based on the total weight of the low-sulfur diesel oil.

The multi-effect additive composition of low-sulfur diesel oil provided by the invention can improve the abrasion resistance (lubricity) of low-flow diesel oil, can inhibit the corrosion of the diesel oil, has little influence on the acidity of the diesel oil due to the addition of the composite additive, and can not cause the acidity of the additivated diesel oil to exceed the limit value of 'not more than 7mgKOH/100 mL' required by the standard.

Drawings

FIG. 1 is a mass spectrum of hydrazide synthesized in example 2.

Wherein only one of R1, R2, R3 and R4 is alkenyl, and the rest is hydrogen. R5 and R6 are hydrogen. Mass spectrogram: the molecular ion peak of undecenyl, dodecenyl and tridecenyl substituted hydrazide is represented by m/z-266,280,294, and the isotopic peaks of three hydrazides are represented by m/z-267,268,281,282,295,296.

Detailed Description

The present invention is further illustrated by the following examples.

In these examples, the rust inhibitive performance of diesel oil was measured by mixing 300mL of the sample with 30mL of distilled water or synthetic seawater as described in GB/T11143-2008, immersing the whole of a cylindrical test steel rod therein, and stirring at 60 ℃. The test period is 24h, and the corrosion trace and the corrosion degree of the test copper rod are observed after the test period is finished.

In these examples, the lubricity of the diesel fuel was measured on a High-Frequency Reciprocating Rig (HFRR) (manufactured by PCS instruments of UK) at 60 ℃ in accordance with the method described in CEC-F-06-A-96 or ISO/FDIS 12156-1 (ASTM D-6079), and the Wear Scar Diameter (WSD) was obtained by correcting the effects of temperature and humidity, and the reported result WS1.4 was obtained. The acid value is measured by GB/T7304 method, and the acidity is measured by GB/T258 method.

The following examples were carried out without adding any other substances as solvents.

Some of the commercial products (unconventional commercial products) in the examples were brand numbers:

the castor oil is industrial castor oil produced by Xinhe biological technology limited company in Liaoshi city of inner Mongolia; the soybean oil is edible soybean oil produced by the goldfish company; the cottonseed oil is an industrial product produced by shiguang cotton industries, ltd, in the hebei chenchenchen station; the rapeseed oil is 'double low' rapeseed oil produced by the Hunan Yingcheng grease industry Limited company; the biodiesel is refined biodiesel which is produced by Ningbo Jersen biodiesel GmbH and is distilled to remove saturated fatty acid; sorbitol is an analytical grade reagent from Aladdin reagent; glycerol is an analytical reagent for the national drug group.

Example 1

This example is the preparation of hydrocarbyl-substituted succinylhydrazide.

50g (0.19mol) of dodecenylsuccinic anhydride and 6.0g (0.19mol) of hydrazine were placed in a three-necked flask reactor equipped with an electric stirrer, a thermometer, a reflux trap and a nitrogen inlet, nitrogen was introduced thereinto to heat and stir at 30 ℃ and the reaction was carried out for 1 hour with nitrogen purging, whereby a product was produced, and the acid value was measured to be 20.6 mgKOH/g.

Example 2

This example is the preparation of alkenyl succinyl hydrazide.

50g (0.19mol) of dodecenyl succinic anhydride (containing a small amount of undecenyl succinic anhydride and tridecenyl succinic anhydride) and 11.2g (0.19mol) of hydrazine hydrate (85 percent by weight) are placed in a three-neck flask reactor provided with an electric stirrer, a thermometer, a reflux water separator and a nitrogen inlet pipe, nitrogen is introduced, the mixture is heated and stirred to 150-160 ℃, nitrogen is used for blowing and reacting for 3 hours, and a product is produced, wherein the acid value is 19.9 mgKOH/g.

Example 3

This example is the preparation of hydrocarbyl-substituted succinylhydrazide.

100g (0.31mol) of hexadecenyl succinic anhydride and 18.6g (0.31mol) of ethyl hydrazine are placed in a three-neck flask reactor provided with an electric stirrer, a thermometer, a reflux water separator and a nitrogen inlet pipe, nitrogen is introduced, the stirring temperature is controlled at 80 ℃, the reaction is carried out for 5 hours by nitrogen purging, and the product is generated, and the acid value is 22.5 mgKOH/g.

Examples 4 to 9 preparation of fatty acid polyol esters

Example 4

Placing 100g of castor oil, 17g of 1, 2-propylene glycol (the molar ratio of the castor oil to the l, 2-propylene glycol is about 1:2) and l.2g of p-toluenesulfonic acid into a reactor provided with an electric stirrer, a thermometer, a reflux condenser and a nitrogen inlet pipe, introducing nitrogen for 5-10 minutes, keeping weak nitrogen flow in the reaction process, heating and stirring to 150 ℃, reacting for 5 hours, and then adding 0.5g of Ca (OH)₂Neutralizing the p-toluenesulfonic acid, cooling and filtering to obtain the product with an acid value of 0.4 mgKOH/g.

Example 5

Placing 100g of soybean oil, 30g of sorbitol (the molar ratio of the soybean oil to the sorbitol is about 1:1.5) and 2.8g of sodium/methanol catalyst in a reactor provided with an electric stirrer, a thermometer, a reflux condenser tube and a nitrogen inlet tube, introducing nitrogen for 5-10 minutes, keeping a weak nitrogen flow in the reaction process, heating and stirring to 160 ℃, reacting for 6 hours, cooling to 90 ℃, adding 3.2g of acid clay for neutralization and filtering to obtain the product, wherein the acid value is 0.3 mgKOH/g.

Example 6

Placing 100g of cottonseed oil, 10.5g of 1, 2-butanediol (the molar ratio of the cottonseed oil to the 1, 2-butanediol is about 1:2) and l.5g of dimethylcyclohexylamine into a reactor provided with an electric stirrer, a thermometer, a reflux condenser tube and a nitrogen inlet tube, introducing nitrogen for 5-10 minutes, keeping weak nitrogen flow in the reaction process, heating and stirring to 150 ℃, reacting for 7 hours, and cooling to obtain the product with the acid value of 0.8 mgKOH/g.

Example 7

100g of rapeseed oil, 51g of glycerol (the molar ratio of the rapeseed oil to the glycerol is about 1:5) and 1.0g of KOH are placed in a reactor provided with an electric stirrer, a thermometer, a reflux condenser tube and a nitrogen inlet tube, nitrogen is introduced for 5-10 minutes, weak nitrogen flow is kept in the reaction process, the temperature is raised to 200 ℃ by heating and stirring, the reaction is carried out for 6 hours, the mixture is kept stand in a separating funnel, excessive glycerol is separated out, 5g of acid clay and 1g of diatomite are added, and suction filtration is carried out, so that the filtrate is the product, and the acid value is 0.3 mgKOH/g.

Example 8

Putting 100g of tall oil fatty acid (produced by Arizonal corporation, USA, the brand number is 2LT) and 40g of glycerol (the molar ratio of the tall oil fatty acid to the glycerol is about 1:1.2) in a reactor provided with an electric stirrer, a thermometer, a reflux condenser tube and a nitrogen inlet tube, introducing nitrogen for 5-10 minutes, keeping weak nitrogen flow in the reaction process, heating, stirring and heating to 200 ℃, and reacting for 10 hours to obtain a finished product, wherein the acid value is 0.9 mgKOH/g.

Example 9

100g of biodiesel and 35g of glycerol (the molar ratio of the biodiesel to the glycerol is about 1:1.2) and 1.0g of KOH are placed in a reactor provided with an electric stirrer, a thermometer, a reflux condenser tube and a nitrogen inlet tube, nitrogen is introduced for 5-10 minutes, weak nitrogen flow is kept in the reaction process, the mixture is heated and stirred to 200 ℃, 2.2g of acidic ion exchange resin is added for reacting for 6 hours, and a base catalyst is neutralized to obtain a finished product, wherein the acid value is 0.1 mgKOH/g.

Examples 10-17 are the preparation of diesel additive compositions provided by the present invention.

Different compositions were obtained by mixing a hydrocarbyl-substituted succinhydrazide selected from one of examples 1 to 3 as component a and a polyol ester selected from one of examples 4 to 9 as component b in the weight ratios shown in Table 1.

TABLE 1 preparation of Multi-Effect additive compositions

Comparative example

Comparative example 1 ester type antiwear agent 1 (fatty acid ester type diesel antiwear agent manufactured by Runki Co., Ltd. under the trade name InfiniumR655, acid value 0.54mgKOH/g)

Comparative example 2 is an ester type antiwear agent 2 (fatty acid ester type diesel antiwear agent manufactured by Jiangsu Innovation Co., Ltd., acid value 0.3mgKOH/g)

Comparative example 3 is a T746 rust inhibitor. (dodecenylsuccinic acid type rust inhibitor produced by Liaoning Dalian Shunshun chemical plant, acid value 359.6mgKOH/g)

Example 18

This example is the lubricity effect of the additives prepared in examples 10, 11, 12, 13, 14, 15, 16, 17 for use in diesel fuel. The physical and chemical properties of the DF-06 blend oil are shown in Table 2, the HFRR method (ISO12156-1) grinding trace diameter WS1.4 of the additivated diesel oil is shown in Table 3, and when the grinding trace diameter is less than 460um (60 ℃), the lubricity of the diesel oil is qualified. The smaller the WS1.4 data, the better the sample abrasion resistance.

Example 19

This example shows the rust resistance effect of the additive compositions prepared in examples 10, 11, 12, 13, 14, 15, 16, 17 in diesel fuel, DF-06 blend oil, the physicochemical properties of which are shown in Table 2 and the rust resistance effect of which is shown in Table 4. Experimental method GB/T11143-2008. The smaller the 24h rust percentage is, the smaller the rust is, the data is 0, the rust is not generated, and the additive has the best rust resistance effect.

TABLE 2 physicochemical properties of diesel fuel

TABLE 3 improvement of lubricity and increase in acidity of additives for diesel fuels

As can be seen from Table 3, the alkenyl succinyl hydrazine of the component a is added independently, so that the lubricity of the low-sulfur diesel oil is improved to a certain extent, the fatty acid polyol ester of the component b is added independently, so that the lubricity of the low-sulfur diesel oil is also improved, but after the composite additive of the component a and the component b in a ratio of 1: 1-6 is added, the lubricity of the low-sulfur diesel oil is greatly improved, and the effect is greatly enhanced compared with that of the respective independent addition. The anti-wear effect after compounding is better than that of the fatty acid ester type anti-wear agent (comparative examples 1 and 2) commonly used in industry, and the anti-wear effect is far better than that of the commonly used antirust agent T746. The synergistic effect of the anti-wear effect is poor after the component a and the component b are compounded in a ratio of 1: 9. The influence of the composite additive of the component a and the component b on the acidity of the diesel oil is small, the acidity of the diesel oil is greatly increased after the industrial antirust agent T746 is added, the acidity of the diesel oil exceeds 7mgKOH/100mL after 200mg/kg is added, and the acidity of the diesel oil exceeds the limit value required by the standard.

TABLE 4 improvement of rust inhibition of diesel with additives

As can be seen from Table 4, the additives provided by the present invention (examples 10 to 17) greatly improved the rust inhibitive performance of diesel oil, better than when either component a or component b was used alone, and better than the conventional industrial fatty acid ester type diesel anti-wear agents (comparative examples 1 and 2). The antirust effect of the component a and the component b compounded in the ratio of 1: 1-6 is better than that of the component a and the component b compounded in the ratio of 1:9 (example 17).

Claims

1. A low acid diesel multi-effect additive composition comprising: a) hydrocarbyl-substituted succinylhydrazide; b) the polyol ester of the fatty acid is C8-C24, wherein the weight ratio of a to b is 1: 1-6, the alkyl of the alkyl-substituted succinyl hydrazide is C8-C18 alkenyl, and the polyol is glycerol.

2. The composition of claim 1 wherein said hydrocarbyl-substituted succinhydrazide is selected from at least one of undecenylsuccinylhydrazide, dodecenylsuccinylhydrazide, tridecenylsuccinylhydrazide, tetradecenylsuccinylhydrazide, pentadecenylsuccinylhydrazide, hexadecenylsuccinylhydrazide, heptadecenylsuccinylhydrazide, octadecenylsuccinylhydrazide, undecenylsuccinylhydrazide, dodecenylsuccinylhydrazide, tridecenylsuccinylhydrazide, tetradecenylsuccinylhydrazide, pentadecenylsuccinylhydrazide, hexadecenylsuccinylhydrazide, heptadecenylsuccinylhydrazide, octadecenylsuccinylhydrazide.

3. The composition of any one of claims 1 to 2, wherein the hydrocarbyl-substituted succinhydrazide is prepared by reacting a hydrocarbyl-substituted succinic anhydride with hydrazine.

4. The composition according to claim 3, wherein the reaction conditions are a reaction temperature of 0 to 200 ℃ and/or a reaction time of 1 to 36 hours and/or a molar ratio of the hydrocarbyl-substituted succinic anhydride to hydrazine of 1:0.5 to 10.

5. A composition according to claim 3 wherein the hydrazine is selected from hydrazine, hydrazine hydrate, aqueous hydrazine hydrate or C1 to C20 hydrocarbyl hydrazine.

6. The composition of claim 1 wherein the polyol ester of a C8-C24 fatty acid is selected from the group consisting of transesterification products of natural fats and oils with glycerol, esterification products of fatty acids with glycerol, and reaction products or mixtures of fatty acid methyl esters with glycerol.

7. The composition according to claim 6, wherein the natural oil is a vegetable oil or an animal oil, and/or the fatty acid is a refined tall oil fatty acid from which rosin acid is removed, and/or the fatty acid methyl ester is a mixture of fatty acid methyl esters mainly comprising C16-C18.

8. A low-sulfur diesel oil composition, which comprises low-sulfur diesel oil and the low-acid diesel oil multi-effect additive composition as claimed in any one of claims 1 to 7, wherein the content of the additive in the diesel oil is 10 to 500mg/kg based on the weight of the low-sulfur diesel oil.

9. A method for improving the anti-wear and anti-rust capability of low-sulfur diesel oil is characterized in that the low-acid diesel oil multi-effect additive composition as defined in any one of claims 1 to 7 is added into the low-sulfur diesel oil, and the content of the additive in the diesel oil is 10 to 500mg/kg based on the total weight of the low-sulfur diesel oil.