JPH01245092A - Fuel oil additive antioxidant composition - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an antioxidant composition that is blended into fuels such as gasoline, kerosene, jet fuel oil, etc. in a proportion of 5 to 100 ppm. This antioxidant is added for the purpose of preventing unstable diolefins in the fuel from being oxidized and polymerized to form gum.

[Conventional technology]

Fuels such as gasoline, kerosene, and jet fuel oil usually contain unstable diolefins, which are susceptible to oxidation and
Polymerizes to form gum.

Gum is normally dissolved in fuels such as gasoline and jet fuel, but when the fuel evaporates in the engine, it becomes deposits and adheres to the carburetor, intake manifold, intake valves, etc., and disrupts these normal operations. prevents operation.

Therefore, in order to prevent the formation of gum, a phenolic compound with radical scavenging properties is blended to prevent polymerization by capturing peroxy radicals generated by the reaction between hydrocarbons such as diolefins and oxygen.

Such phenolic compounds include: ■ 2,6-di-t-butyl-4-methylphenol ■ 2,6-di-t-butylphenol ■ 4,4'-
Methylenebis(2,6-di-t-butylphenol) ■ 2,6-di-t-butylphenol (83-88 parts) and 2.4.6-tri-t-butylphenol (17
~12 parts) (trade name: EthyIA Antioxidant 735, manufactured by Ethyl Corporation), etc. are approved by British Standard DERD 2494.

The effects of these antioxidants are expressed by the oxygen absorption induction period (minutes) relative to the concentration of the antioxidant added, and the longer the period, the better the antioxidant effect. The oxygen absorption induction periods when 20 ppm and 40 ppm of each phenolic compound were added to gasoline are shown in No. 16. The oxygen absorption induction period was measured in accordance with ASTM-D-525) 1 (test temperature: 120°C).

Table 1 *Product Name: Manufactured by Ethyl Corporation Incidentally, the oxygen absorption induction period of Ganlin when no antioxidant is added is 65 minutes.

[Problem to be solved by the invention]

All of these antioxidants have a freezing point higher than 0°C, and when added to kerosene, gasoline, etc., they tend to need to be dissolved in a solvent such as toluene before being added, which is cumbersome. For this reason, the active ingredient 2,6-di-t-butyl-4-methylphenol', which has been dissolved in a hydrocarbon solvent in advance,
1-10~40] Liquid products containing 1i170 are commercially available, but all of these liquid antioxidants contain -
Precipitation of crystals is observed in the severe cold of 20°C, and as a result, there are problems such as the antioxidant precipitating during winter storage and clogging the storage tank strainer, feed nozzle, etc., and there is no precipitation of crystals even at low temperatures. The development of liquid antioxidants with excellent workability is strongly desired.

[Means to solve the problem]

The present inventors have previously discovered a standardization inhibitor composition that can maintain its liquid state even under conditions of -3°C to -13°C (Japanese Patent Application No. 61-202127 Specification 8). After further investigation, we discovered an antioxidant composition that can maintain a liquid state at at least -20°C, leading to the present invention.

That is, the present invention includes (A) component: 2.6-di-t-butyl-4-methylphenol (B) component: 50 to 80% by weight of 2.6-di-t-butylphenol.
and an alkylphenol mixture containing 50 to 20% by weight of alkylphenol represented by the following formula [where & is hydrogen, R2-R4 is hydrogen or has 4 to 8 carbon atoms]
Component (C): Hydrocarbon solvent The ratio of the above components (A) and (B) is 5/95 by weight.
-45155, and contains 3 to 50 parts by weight of the above component (to 100 parts by weight of the total amount of components (A) and (B)). It is something that provides something.

Component (A), 2,6-di-t-butyl-4-methylphenol, is obtained, for example, from Sumilizer ■BHT (trade name) from Sumitomo Chemical ■, and component (B), the alkylphenol mixture, is obtained from Mitsubishi Yuka ■. can do.

Component (B) is 2,6-di-t-butylphenol.
This is an alkylphenol mixture containing 0 to 80wk% of 2,6-di-di-butylphenol, which can be obtained as a middle distillate or high-boiling fraction during distillation in the monobutylphenol manufacturing process (especially Kaisho 60-252
(See Publication No. 439).

Or by-products such as these middle distillates and high boiling point fractions,
It can also be obtained by mixing 2,6-di-t-butylphenol in a certain proportion.

Therefore, the alkylphenols other than 2,6-di-t-butylphenol in component CB) that account for 20 to 50% by weight are ortho-t-butylphenol, 2,4-
Di-t-butylphenol, 2,5-di-t-butylphenol, 2,4.6-tri-butylphenol, 2-t-7'thyl-6-octylphenol, 2-t-butylphenol
-7” thyl-4-octylphenol, 2-t-butyl-6-5ee-butylphenol, 2-t-butyl-4
-5ec-butylphenol and the like can be mentioned.

Component (C) is a hydrocarbon solvent whose melting point is 12
A temperature below 0°C is used. Specific examples include aliphatic solvents such as n-hexane and n-heptane, aromatic solvents such as toluene and xylene, and kerosene.

These may be a mixture.

In order to maintain the liquid state at -20°C, the amount of component (C) added must be at least 3 parts by weight, and at least 50 parts by weight per 100 parts by weight of the mixture of components (A) and (B). Addition is impractical because components (A) and (B), which are effective antioxidant components, are too diluted. In general, 3
~30 parts by weight is used.

Since the fuel oil additive composition of the present invention remains liquid at at least -20°C under atmospheric pressure, it is easy to handle even under extremely cold conditions.

Regarding the mixing mode of the antioxidant composition of the present invention, the method, mixing order, mixing conditions, etc. are all arbitrary.

〔Example〕

Next, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited by these in any way.

<Example 1> 2.6-di-t-butyl-4-methylphenol 351
Yaribe, and as component (B), 50.2% by weight of 2.6-di-t-butylphenol, 13.3 parts by weight of 2-B-butyl-6-t-butylphenol, and 2.4-di-t- 65 parts by weight of an alkylphenol mixture containing 13.5 parts by weight of butylphenol, 3.3 parts by weight of 2,5-di-t-butylphenol, 2,4,6-tri-t-butylphenol, and 2.2 parts by weight of Li, respectively. A composition was prepared by adding white kerosene (home use No. 1) to the mixture at a concentration of 3% by weight, and used as a test sample for the coagulation test below.

In the coagulation test, the sample was sealed in a test tube, and the entire test tube was immersed in an oil bath kept at a constant temperature of -20° C., and the presence or absence of coagulation and crystal precipitation was visually observed.

As a comparative example, a mixture of 2,6-di-t-butylphenol dissolved in toluene was used as a sample. The results are shown in Table 2.

The composition of the present invention showed no solidification or crystal precipitation even after being left for 135 hours.

(Leaving space below) Table 2 ×...Crystal precipitation Δ...-Partial crystal precipitation ○...No coagulation or crystal precipitation Next, this antioxidant composition was added to gasoline and kerosene at 20 ppm and 40 ppm, respectively. The oxygen absorption induction period was set at 120℃ for gasoline and 150℃ for kerosene.
Measured according to STM-D-525. The results are shown in Table 3.

In addition, 2,6-di-t-butyl-4 is added to 70 parts by weight of toluene.
- When a mixture in which 30 parts by weight of methylphenol is dissolved is added to gasoline at z o ppm and 40 ppm, the oxygen absorption induction period is 150 minutes and 170 minutes, respectively;
In the case of kerosene, the time was 100 minutes and 130 minutes, respectively.

Table 3 (Example 2) 2,6-di-t-butyl-4-methylphenol used in Example 1! : To the mixture of component (B) with the alkylphenol mixture, each component (C) shown in Table 3 was added at each a degree, and a coagulation test was conducted in the same manner as in Example 1. 135
The results of time Mj & are shown in Table 4.

Claims (1)

[Claims] 1) Component (A): 2,6-di-t-butyl-4-methylphenol (B) component: 50 to 80% by weight of 2,6-di-t-butylphenol
and an alkylphenol mixture containing 50 to 20% by weight of alkylphenol represented by the following formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ [In the formula, R_1 is hydrogen, R_2 to R_4 are hydrogen or an alkyl group having 4 to 8 carbon atoms It is. ] Component (C): Hydrocarbon solvent The ratio of the above components (A) and (B) is 5/95 by weight.
~45/55, and the above (C) component is 3 to 50 parts by weight per 100 parts by weight of the total amount of components (A) and (B).
A fuel oil additive antioxidant composition containing part by weight.