KR20110104714A - 2-substituted half-succinic alkyl ester derivatives useful as fuel oil lubricity additives - Google Patents

Abstract

The present invention relates to a novel succinic acid ester derivative which improves the lubricity of fuel oil, and more particularly to a two-substituted half-succinic acid alkyl ester derivative having a structure having an ester group and a carboxyl group. The succinic acid ester derivatives of the present invention do not contain molybdenum, zinc and phosphorus, and because they contain ester groups, have excellent biodegradability, and can greatly improve the lubricating performance of fuel oil when added to the fuel oil.

Description

2-Substituted Half-Succinic Alkyl Ester Derivatives useful as Fuel oil Lubricity additives}

The present invention relates to a half-succinic acid ester derivative having a novel structure containing both an ester group and a carboxyl group in one molecule. The 2-substituted half-succinic acid alkyl ester derivative of the present invention can be usefully applied as a lubricant additive for fuel oil. Do.

With the recent development of the industry, precision instruments and various industrial parts are required to operate under harsher environmental conditions, and in order to satisfy this, lubrication additives having excellent lubrication performance are used.

These lubricant additives are additives that are included in the lubricating oil to form a film on the metal surface to prevent abrasion caused by the contact between the metal and the metal to exert a load carrying capacity. However, lubricating additives have the advantage of improving the efficiency of the machine, reducing fuel consumption and reducing energy by reducing wear caused by metal-to-metal contact, but soil pollution, water pollution, etc., caused by oil leakage during use There is a problem that causes.

In this way, the lubricating additive forms a film on the metal surface to perform physical or chemical functions. Therefore, the lubricant additive functions as an anti-wear agent according to the chemical structure and elements contained therein, thereby significantly reducing the energy generated by friction with the metal. It is effective and shows excellent wear resistance with compatibility. Among the well-known additives include molybdenum, and known techniques related to such antiwear agents include organic molybdenum compounds and preparation methods (US Pat. No. 4,889,647, US Pat. No. 5,137,647, US Pat. No. 5,412,130), Organic Molybdenum Complex (JP-A-5-247075), Organic Molybdenum Abrasion Additive (US Pat. No. 4,164,473), Multifunctional Additive for Lubricant (US Pat. No. 4,474,674), Molybdenum Compound Coating Lubricating oils (US Pat. No. 6,174,842) and the like are known. However, the known additives are problematic in that they have limited solubility in oil, are expensive in terms of cost, and contain heavy metals such as molybdenum and zinc. In addition, the composition containing phosphorus may cause corrosion of the metal, may cause curing when used in an elastomer such as rubber, and when added to the fuel oil of the exhaust gas catalyst of the internal combustion engine Since there is a problem that can cause poisoning, the development of new antiwear agents is constantly required.

Thus, abrasion agents containing 2-mercapto-benzothiazole (Y. Wan, Q. Pu, Q. Xue, Z. Su, Wear 192 (1996) 74-77) are known, which are molecules There is a problem in that there is a limit in abrasion resistance and bad biodegradability since there is little sulfur content and does not include a group that shows biodegradability.

On the other hand, many attempts to use succinic acid derivatives as fuel oil additives are known. For example, polyalkyl or polyalkenyl succinimide ethers (US Pat. No. 6,352,566), alkenyl succinic anhydride compositions (US Pat. No. 6,348,132), alkenyl succinic anhydride methods (US Pat. No. 5,021,169), emulsions Alkyl maleate ammonium derivatives for polymerization (Colloid Polym Sci 275, 1-8 (1997)), polymeric surfactants derived from maleic anhydride (Langmuir, 13, 176-181 (1997)), maleic anhydride sizing agents (PCT WO 00/79050), polyalkylene succinic acid imide derivatives (US Pat. No. 6,358,892), copolymers of maleic anhydride / polyalkylene (US Pat. No. 6,451,920), alkenylsuccinic acid imides and bis (hydroxyaromatic) carboxylic acids And reactants (US Pat. No. 5,445,750), lubricant additives (US Pat. No. 5,384,055), multifunctional ashless dispersants (US Pat. No. 5,362,410) and the like are known. In addition, a lubricant composition (US Pat. Nos. 4,462,918, 5,275,749) which provides abrasion resistance and corrosion resistance, comprising a component of the N-acyl-N- (alkoxy) alkylaminooxysuccinic ester type (aspartic acid ester) Succinic acid semi-amides useful as a compound (Korean Patent Publication No. 10-2005-0046781) and the like are known. However, the succinic acid derivatives used in the above patents are mostly imide compounds and are used as fuel additives and lubricating oil additives, which are used as dispersants for dispersing the produced debris, which makes it difficult to apply them as lubricating additives.

In addition, Korean Patent No. 10-532236 discloses a succinic acid derivative used as a metal covalent additive represented by the following formula (A).

[Formula A]

In Formula A, R is a C ₈ ~ C ₁₆ alkyl or alkenyl group, R ₁ is -OCH ₂ CH ₂ N (R ₂ ) ₂ or -N (CH ₂ CH ₂ OR ₂ ) ₂ .

However, the succinic acid derivatives disclosed in the Republic of Korea Patent No. 10-532236 is introduced into a hydrophilic group in the R ₁ portion of the metal covalent, in particular, in the metal processing such as cutting, grinding, rolling, etc. It is only the invention which the use was disclosed as an additive which adds lubricity and rust prevention property by adding to metal processing oil, such as water-soluble synthetic oil. However, the present invention has a distinct difference in that it uses a lipophilic group in the R ₁ portion to specify the use as an additive for improving fuel lubricity and biodegradability, which is used for fuel oil, specifically gasoline, diesel, and the like.

In addition, as confirmed in the following examples, the succinic acid derivative disclosed in Korean Patent No. 10-532236 was not dissolved in fuel oil when used as an additive of non-polar fuel oil (light oil), and as a result, the lubrication performance was not properly expressed. It was confirmed experimentally that the failure. This is a result confirming that even the additive having a lubricating performance, the required additive effect is significantly different depending on the base oil (base oil) to be added.

Therefore, the succinic acid derivative disclosed in Korean Patent No. 10-532236 has a different chemical structure compared with the succinic acid derivative of the present invention, and in particular, base oils applied as lubricant additives are different from each other as water-soluble metal covalent and water-insoluble fuel oils. Lubricant invention for use.

Accordingly, the present inventors have made efforts to solve the above problems, and prepared succinic acid derivatives in which an ester group and a carboxyl group were introduced into the molecule at the same time, and when this was applied as a lubricating additive to fuel oil, the lubricating performance was remarkably improved, thus completing the present invention. Was done.

Accordingly, an object of the present invention is to provide a succinic acid ester-based lubricant additive having excellent biodegradability and environmental friendliness while maintaining equivalent lubricity or higher than that of the conventional lubricant additive.

The present invention is characterized by a 2-substituted half-succinic acid alkyl ester derivative represented by the following formula (1).

[Formula 1]

In Formula 1, R Is a C ₄ to C ₁₆ alkyl or alkenyl group, R ₁ It is an alkyl group of C ₁ ~ C _18.

In addition, the present invention provides a method for producing a 2-substituted half-succinic acid alkyl ester derivative represented by the following formula (1) prepared by ring-opening reaction of the succinic anhydride represented by the following formula (2) and the alcohol represented by the following formula (3) It features.

R Is a C ₄ to C ₁₆ alkyl or alkenyl group, R ₁ It is an alkyl group of C ₁ ~ C _18.

The present invention also features a lubricant additive for fuel oil containing the 2-substituted half-succinic acid alkyl ester derivative.

The 2-substituted half-succinic acid alkyl ester derivatives of the present invention have an ester group in the molecule and thus have excellent biodegradability, and excellent solubility in fuel oil, thereby greatly improving the lubricating performance of fuel oil when applied as a lubricating additive of fuel oil. You can.

Hereinafter, the present invention will be described in more detail.

The present invention relates to a 2-substituted half-succinic acid alkyl ester derivative which simultaneously contains an ester group and a carboxyl group in a molecular structure which is applied to fuel oil to improve lubricating performance, and is characterized by the following formula (1).

[Formula 1]

In Formula 1, R Is a C ₄ to C ₁₆ alkyl or alkenyl group, R ₁ It is an alkyl group of C ₁ ~ C _18.

At this time, when the carbon number of the alkyl or alkenyl group of R is less than 4 or more than 16, the alkyl group or alkenyl group having carbon number in the above range is preferable because the effect of solubility on fuel oil may be lowered or there may be a problem in lubrication performance. . In addition, when the carbon number of the alkyl group of R ₁ exceeds 18, there may be a problem of solubility in fuel oil, alkyl group in the above range is preferred.

In addition, the present invention is 2- represented by the following formula 1 by a ring-opening esterification reaction of a succinic anhydride substituted with an alkyl or alkenyl group having 4 to 16 carbon atoms represented by the formula (2) and an alcohol represented by the formula (3) It relates to a process for preparing substituted half-succinic acid alkyl ester derivatives.

R Is a C ₄ to C ₁₆ alkyl or alkenyl group, R ₁ It is an alkyl group of C ₁ ~ C _18.

Examples of succinic anhydrides represented by Formula 2 include 2-butyl succinic anhydride, 2-hexyl succinic anhydride, 2-octyl succinic anhydride, 2-dodecyl succinic anhydride, 2-tetradecyl succinic anhydride, and 2-hexadecyl succinic anhydride. Alkenyl groups such as succinic anhydride substituted with an alkyl group, or 2-hexenyl succinic anhydride, 2-octenyl succinic anhydride, 2-dodecenyl succinic anhydride, 2-tetradecenyl succinic anhydride, and 2-hexadecenyl succinic anhydride are substituted. Succinic anhydride, or mixtures thereof, may be used.

The alcohol represented by Formula 3 includes a fatty alcohol prepared from plant-derived fatty acid methyl ester (biodiesel) as an alcohol of C ₁ to C ₁₈ . Plant-derived fatty alcohols can be prepared by hydrogenation of plant-derived fatty acid methyl esters in the presence of a copper-containing metal oxide catalyst. The amount of the copper-containing metal oxide catalyst in preparation is 0.2 to 20% by weight based on the fatty acid ester, the reaction temperature 150 ~ 300 ℃, the reactor pressure is preferably 80 to 300 atm. If the amount of the catalyst used is less than 0.2% by weight, there may be a disadvantage in that the reaction yield is low due to the inferior catalyst performance. If the amount of the catalyst is used in excess of 20% by weight, the benefits of the increase are not economical. In addition, when the reaction temperature and the reactor pressure is also lower than the above conditions, the reaction rate and the yield may be lowered. On the contrary, if the reaction temperature and the reactor pressure are too high, the productivity may decrease, such as a side reaction, and thus, the reaction temperature and the reactor pressure are preferably performed in the above reaction conditions. Plant-derived fatty acid methyl esters used in the production of the alcohol are corn oil, cottonseed oil, linseed oil, peanut oil, rapeseed oil, safflower oil Fatty acid methyl esters derived from oils, soybean oils, sunflower oils, palm oils, coconut oils, etc. can be used, but are not limited thereto.

The amount of the alcohol may be used in the range of 0.8 to 1.9 molar ratio with respect to succinic anhydride represented by the formula (2), preferably 0.9 to 1.5 molar ratio. If the amount of the alcohol is too small, there may be a problem that the yield of the succinic acid ester derivative is lowered, if too much is used, the content of the compound having a carboxyl group in the molecular structure is low, it is difficult to exert the lubricating performance of the fuel oil and economical problems There can be.

The ring ring-opening esterification temperature is preferably 50 to 140 ° C, more preferably 70 to 120 ° C. If the reaction temperature is less than 50 ℃ there may be a problem that the reaction rate is low to remain unreacted excess, if the reaction temperature exceeds 140 ℃ to produce a derivative having the desired lubricating performance is low content of the compound having a carboxyl group in the molecular structure Hard to do and not economical

The reaction time is preferably 2 to 24 hours, more preferably 4 to 12 hours. If the reaction time is too short, an unreacted substance may be left. If the reaction time is too long, an additional esterification reaction of a 2-substituted half-succinic acid alkyl ester derivative may generate a dialkyl succinic acid ester derivative, resulting in an ester group content of carboxyl group. It is more difficult to exert the lubricating performance of fuel oil.

The present invention also features a lubricating additive for fuel oil containing the 2-substituted half-succinic acid alkyl ester derivative.

The fuel oil may be one selected from gasoline, diesel oil, bunker C oil and lubricating base oil, and preferably, diesel oil. The content of the 2-substituted half-succinic acid alkyl ester derivatives in the fuel oil composition is preferably 50 to 5000 ppm by weight. When the content is less than 50 ppm by weight, the effect of addition is minimal, whereas the content is 5000 ppm by weight. If it is exceeded, there may be an economic problem.

The 2-substituted half-succinic acid alkyl ester derivative represented by Chemical Formula 1 according to the present invention has an ester group in its molecular structure, which is highly biodegradable, environmentally friendly, and significantly improves lubrication performance when used in addition to fuel oil. You can get the effect.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited by the following Examples.

[Example]

Preparation Example 1 Preparation of Soybean Oil-Derived Fatty Alcohol

After 300 mL of high pressure reactor was washed with nitrogen, water was removed for 30 minutes at 120 ° C and 0.01 atm.Then, 100 g of soybean oil-derived biodiesel (Eco-SoyBD, Inc.) and copper chromite ) 9 g was added and hydrogenated at 270 ° C. and 100 atm for 2 hours to produce a hydrogen alcohol. The conversion was 95% and the yield of fatty alcohol was 85%.

Manufacturing example  2 to 4: Sunflower oil , Palm oil, Coconut oil  Preparation of Derived Fatty Alcohols

The same process as in Preparation Example 1, but instead of soybean oil-derived biodiesel, biodiesel derived from sunflower oil (Eco-SunflowerBD, Co., Ltd.) (Production Example 2), palm oil-derived biodiesel (Eco-PalmBD, Co., Ltd.) A fatty alcohol was prepared using Solution (Preparation Example 3) and coconut oil-derived biodiesel (Eco-CocoBD, Co., Ltd.) (Preparation Example 4). Conversion rate and yield of fatty alcohol are shown in Table 1 below.

division Plant-derived Biodiesel % Conversion Fatty alcohol yield (%) Preparation Example 1 Soybean oil-derived biodiesel 95 85 Production Example 2 Biodiesel from Sunflower Oil 94 87 Production Example 3 Palm oil-derived biodiesel 91 84 Preparation Example 4 Biodiesel from Coconut Oil 93 85

Example 1

21.2 g (0.1 mol) of 2-octyl succinic anhydride was dissolved in 8.9 g (0.1 mol) of soybean oil-derived fatty alcohol prepared in Preparation Example 1, and then reacted at 100 ° C. for 6 hours in a two-necked flask equipped with a stirrer and a thermometer. . After the reaction, the reaction product was cooled to room temperature and identified by FT-IR spectrum (BIO-RAD FTS 165 model) .The reaction was performed using a 1856, 1781 cm ^-1 peak by carbonyl ring of 2-octyl succinic anhydride as a reactant. 2-octyl ascertained from the 1735 cm ^-1 peak attributable to the ester group of the 2-octyl succinic ester resulting from the ring-opening reaction and the 3500 cm ^-1 peak attributable to the hydroxyl group of the fatty alcohol and the 1700 cm ^-1 peak due to the carboxyl group 30.1 g (100%) of succinic ester was synthesized quantitatively.

Example  2 to 13 and Comparative example  1 to 2

A succinic acid ester derivative was prepared by performing the same method as Example 1, but adjusting the type and amount of succinic anhydride, the type and amount of alcohol, reaction temperature, and reaction time. Specific matters are as shown in Table 2 below.

division Succinic anhydride Alcohol / amine reaction
Temperature reaction
time Product
FT-IR results
(cm ^-1 , υ _{c = o} )










room



city



Yes One 2-octyl succinic anhydride
21.2 g (0.1 mol) Soybean-derived alcohol
8.9 g (0.1 mol) 80 ℃ 5h 1711, 1735 2 2-octyl succinic anhydride
21.2 g (0.1 mol) Sunflower oil-derived alcohol
8.9 g (0.1 mol) 80 ℃ 5h 1711, 1735 3 2-octyl succinic anhydride
21.2 g (0.1 mol) Palm oil-derived alcohol
8.9 g (0.1 mol) 80 ℃ 5h 1711, 1735 4 2-octyl succinic anhydride
21.2 g (0.1 mol) Coconut derived alcohol
8.9 g (0.1 mol) 80 ℃ 5h 1711, 1735 5 2-octyl succinic anhydride
21.2 g (0.1 mol) Octanol
13.0 g (0.1 mol) 80 ℃ 5h 1711, 1735 6 2-octyl succinic anhydride
21.2 g (0.1 mol) Dodecanol
18.6 g (0.1 mol) 80 ℃ 5h 1711, 1735 7 2-octyl succinic anhydride
21.2 g (0.1 mol) Hexadecanol
24.2 g (0.1 mol) 80 ℃ 5h 1711, 1735 8 2-octyl succinic anhydride
21.2 g (0.1 mol) Octadecanol
27.0 g (0.1 mol) 80 ℃ 5h 1711, 1735 9 2-dodecyl succinic anhydride
26.8 g (0.1 mol) Octanol
13.0 g (0.1 mol) 80 ℃ 5h 1711, 1735 10 2-dodecyl succinic anhydride
26.8 g (0.1 mol) Dodecanol
18.6 g (0.1 mol) 80 ℃ 5h 1711, 1735 11 2-hexadecyl succinic anhydride
16.2 g (0.05 mol)
2-hexadecenyl succinic anhydride
16.1 g (0.05 mol) Octanol
13.0 g (0.1 mol) 80 ℃ 5h 1711, 1735 12 2-hexadecyl succinic anhydride
16.2 g (0.05 mol)
2-hexadecenyl succinic anhydride
16.1 g (0.05 mol) Dodecanol
18.6 g (0.1 mol) 80 ℃ 5h 1711, 1735 13 2-hexadecyl succinic anhydride
16.2 g (0.05 mol)
2-hexadecenyl succinic anhydride
16.1 g (0.05 mol) Hexadecanol
24.2 g (0.1 mol) 80 ℃ 5h 1711, 1735 ratio
School
Yes One 2-hexadecenyl succinic anhydride
32.2 g (0.1 mol) HOCH ₂ CH ₂ N (CH ₃ ) ₂
8.9 g (0.1 mol) 80 ℃ 5h 1735 2 2-hexadecenyl succinic anhydride
32.2 g (0.1 mol) HN (CH ₂ CH ₂ OCH ₃ ) ₂
13.3 g (0.1 mol) 80 ℃ 5h 1715, 1650

Test Example Of fuel oil with succinic acid derivative Lubrication Performance Test

It is a test example for comparing the lubricating performance shown by using the succinic acid ester derivatives prepared in Examples 1 to 13 and Comparative Examples 1 to 2 as a fuel oil additive.

The lubricating performance of the fuel oil composition in which fuel oil (SK Incheon essential oil ULSD) was added to the concentration of 120 ppm by weight of succinic acid ester derivatives prepared according to Examples 1 to 13 and Comparative Examples 1 and 2 was tested. In addition, as a control, the lubricating performance of the diesel oil without addition of the succinic acid ester derivative was tested. Lubrication performance was evaluated using a HFRR (High Frequency Reciprocating Rig) tester (PCS Instrument HFRR tester), the results are shown in Table 3 below.

additive Condition of fuel oil Lubrication Performance (mm) Example 1 Transparency 0.454 Example 2 Transparency 0.435 Example 3 Transparency 0.366 Example 4 Transparency 0.385 Example 5 Transparency 0.434 Example 6 Transparency 0.386 Example 7 Transparency 0.432 Example 8 Transparency 0.434 Example 9 Transparency 0.419 Example 10 Transparency 0.333 Example 11 Transparency 0.427 Example 12 Transparency 0.421 Example 13 Transparency 0.423 Comparative Example 1 opacity 0.600 Comparative Example 2 opacity 0.598 No addition control Transparency 0.609

In Table 3, the fuel oil in which the succinic acid ester derivatives prepared in Examples 1 to 13 according to the present invention was dissolved in diesel oil was found to be transparent, solubility in diesel oil was high, and the lubricating performance measured by the HFRR tester. It can be seen that very good as 0.333 ~ 0.454 mm. However, the conventional succinic acid ester / amide derivatives of Comparative Examples 1 to 2 synthesized using N, N-dimethylaminoethanol or bismethoxyethylamine, not C ₁ to C ₁₈ alcohols, have low solubility in diesel fuel and have low fuel solubility. It can be seen that there is a problem that the lubrication performance is not significantly improved because the significance state is opaque. This is because the existing succinic acid ester / amide derivatives have high water solubility as a metal covalent additive.

As a result, when the 2-substituted half-succinic acid alkyl ester derivative represented by Chemical Formula 1 of the present invention was added to the fuel oil as a lubricating additive, it was confirmed that a fuel oil composition having excellent lubrication performance could be prepared.

Claims (9)

2-substituted half-succinic acid alkyl ester derivatives represented by Formula 1;
[Formula 1]

In Formula 1, R Is a C ₄ to C ₁₆ alkyl or alkenyl group, R ₁ It is an alkyl group of C ₁ ~ C _18.
A method for producing a 2-substituted half-succinic acid alkyl ester derivative represented by the following Chemical Formula 1, which is prepared by ring-opening reaction of a succinic anhydride represented by the following Chemical Formula 2 and an alcohol represented by the following Chemical Formula 3;

R Is a C ₄ to C ₁₆ alkyl or alkenyl group, R ₁ It is an alkyl group of C ₁ ~ C _18.
The succinic anhydride represented by Formula 2 is 2-butyl succinic anhydride, 2-hexyl succinic anhydride, 2-octyl succinic anhydride, 2-dodecyl succinic anhydride, 2-tetradecyl succinic anhydride, 2-hexa At least one selected from decyl succinic anhydride, 2-hexenyl succinic anhydride, 2-octenyl succinic anhydride, 2-dodecenyl succinic anhydride, 2-tetradecenyl succinic anhydride, and 2-hexadecenyl succinic anhydride. A process for preparing a substituted half-succinic acid alkyl ester derivative.
The method of claim 2, wherein the alcohol represented by Chemical Formula 3 is a fatty alcohol prepared from plant-derived fatty acid methyl ester.
The method of claim 4, wherein the vegetable-derived fatty acid methyl ester is corn oil, cottonseed oil, linseed oil, peanut oil, rapeseed oil, safflower oil 2-substituted half-characterized fatty acid methyl ester derived from at least one selected from oil, soybean oil, sunflower oil, palm oil and coconut oil. Method for producing succinic acid alkyl ester derivatives.
The method of claim 2, wherein the ratio of succinic anhydride and alcohol is 1: 0.8 to 1.9 molar ratio.
The method of claim 2, wherein the ring-opening reaction is performed at 50 to 140 ° C.
A lubricant additive for fuel oil containing the 2-substituted half-succinic acid alkyl ester derivative of claim 1.
9. The lubricating additive for fuel oil according to claim 8, wherein the fuel oil is one selected from gasoline, diesel oil, bunker C oil and lubricating base oil.