JPH01247404A - Preparation of alkenylsuccinic anhydride - Google Patents

Abstract

PURPOSE:To improve the reaction efficiency with small amt. of by-products, by reacting an olefinic hydrocarbon with maleic anhydride in the presence of a 10-24C aliph. bromine compd. CONSTITUTION:An olefinic hydrocarbon (A) having an average MW of 50-7,000 (e.g., polybutene) is reacted with maleic anhydride (B) in the presence of 200-10,000ppm (in terms of bromine content) 10-24C aliph. bromine compd. (e.g., decyl bromide) based on the component A under ordinary pressure-20atm at 150-300 deg.C for 2-20hr.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for producing alkenylsuccinic anhydride;
More specifically, the present invention relates to a method for producing alkenylsuccinic anhydride with few by-products and high reaction efficiency by using a specific catalyst.

[Prior art and problems to be solved by the invention] Conventionally, alkenylsuccinic anhydride has been used not only itself, but also its ester derivatives and metal salts.

Amide salts and ammonium salts are used in a variety of applications, including as additives for lubricating oils and fuel oils, as well as plasticizers, paint bases, and paper-making additives.

Such alkenylsuccinic anhydrides are generally produced by reacting olefinic hydrocarbons with maleic anhydride, but this reaction produces by-products such as tar-like substances and solid sludge. Therefore, ■ a filtration step is required to remove such by-products, ■ the reaction pressure gradually increases, ■ the addition rate of maleic anhydride to the olefinic hydrocarbon decreases, or ■ the reaction tank has to be replaced frequently. There are various problems such as the need for cleaning.

In recent years, a method has been proposed in which a bromine-substituted aliphatic compound with a boiling point of 40 to 225°C, such as tetrabromoethane or bromotetrachloroethane, is added to the above reaction (U.S. Pat. No. 3,960,900). , No. 4.029.592). However, this method cannot sufficiently suppress by-products during the reaction.

In addition, a method of adding an organic chlorine compound during the above reaction has also been reported (Japanese Patent Publication No. 52-23668).
In this method, the rate of addition of maleic anhydride to the olefinic hydrocarbon was not sufficient, and the reaction efficiency was unsatisfactory.

Therefore, the present inventor has conducted extensive research in order to overcome the various drawbacks of the conventional methods described above, and to develop a method that can produce alkenylsuccinic anhydride with fewer by-products and high reaction efficiency.

[Means to solve the problem]

As a result, it has been found that the above object can be achieved by adding an aliphatic bromine compound having 10 to 24 carbon atoms to the reaction system during the reaction for producing alkenylsuccinic anhydride.

The present invention was completed based on this knowledge. That is, the present invention provides a method for producing alkenylsuccinic anhydride, which is characterized by reacting an olefinic hydrocarbon and maleic anhydride in the presence of an aliphatic bromine compound having 10 to 24 carbon atoms. be.

In the method of the present invention, an olefinic hydrocarbon and maleic anhydride are used as reaction raw materials.

Here, the olefin hydrocarbon may be appropriately selected depending on the type of alkenylsuccinic anhydride to be produced, but -a has an average molecular weight of 50 to 7000, preferably 1
A hydrocarbon having 00 to 3000 olefinic double bonds, specifically ethylene, propylene, butene,
Hepten.

Polyolefins obtained by homopolymerization or copolymerization of monoolefins such as hexene, polyolefins obtained by homopolymerization or copolymerization of diolefins such as butadiene and pentadiene, and copolymerization of the above monoolefins and diolefins. Examples include polyolefins obtained by

In the method of the present invention, when reacting the olefinic hydrocarbon and maleic anhydride, the reaction system contains 10 to 24 carbon atoms.
It is necessary to have an aliphatic bromine compound of
There are various types of aliphatic bromine compounds. Specifically, decyl bromide.

Preferred examples include monoalkyl bromides such as lauryl bromide and cetyl bromide, and polyalkyl bromides such as decyl tribromide and lauryl dibromide.

Here, if the aliphatic bromine compound has 9 or less carbon atoms, its boiling point is low, so the effect of its addition is small, and if it is 25 or more, the catalytic action is small, and the sufficient effect will not be achieved unless it is added in large quantities. .

On the other hand, even if an aromatic bromine compound is used instead of an aliphatic bromine compound, the desired effect cannot be obtained because the activity is small.

In the method of the present invention, the amount of the aliphatic bromine compound added is not particularly limited and varies depending on the situation and cannot be unambiguously determined, but it is usually added based on the amount of olefinic hydrocarbons present in the reaction system. 200~10000ρρ
m (in terms of bromine amount), particularly preferably 300 to 1000 p
It may be expressed as a ratio of pm (in terms of bromine amount).

The method of the present invention involves reacting the above olefinic hydrocarbon and maleic anhydride in the presence of a predetermined aliphatic bromine compound, and the reaction conditions vary depending on the type of olefinic hydrocarbon and aliphatic bromine compound used. The pressure may be selected as appropriate depending on various situations, including: - For boat fishing, the pressure should be between normal pressure and 20 atm, and the temperature should be set in the range of 150 to 300°C, preferably 230 to 260°C; 2 to 20 hours,
Preferably, the reaction may be carried out for 3 to 10 hours.

〔Example〕

Next, the present invention will be explained in more detail with reference to Examples and Comparative Examples.

Examples 1-4 and Comparative Examples 1-2 Capacity l with stirrer! 470 g of polybutene with an average molecular weight of 940 was placed in a stainless steel reaction vessel.

54 g of maleic anhydride and a predetermined amount of alkyl bromide were added, the atmosphere was replaced with nitrogen gas, and the temperature was raised to 250 g under normal pressure.
The reaction was carried out at 'C for 5 hours.

Thereafter, unreacted maleic anhydride was distilled off under reduced pressure to obtain alkenylsuccinic anhydride.

The saponification value of this alkenylsuccinic anhydride was measured, and the addition rate of maleic anhydride was calculated.

On the other hand, after washing the reaction vessel twice with 1ffi of toluene, II! of acetone was added to the reactor, and the by-products adhering to the inside of the reaction vessel were dissolved by thorough stirring. Furthermore, after taking it out and removing acetone, the amount of by-products was determined. These results are shown in Table 1.

Comparative Example 3 The same operation as in Example 1 was performed except that chlorinated paraffin 437 ppa+ (chlorine amount 175 ppm) (based on polybutene) was used instead of cetyl bromide. The results are shown in Table 1.

(Left below) [Effects of the invention] As with steaming, the method of the present invention significantly reduces by-products compared to conventional methods, and also reduces the addition rate of maleic anhydride to olefinic hydrocarbons. alkenylsuccinic anhydride can be obtained with extremely high reaction efficiency.

This alkenylsuccinic anhydride is widely and effectively used in various fields such as various additives for lubricating oils and fuel oils, plasticizers, and paper manufacturing additives.

Therefore, the present invention has extremely high utility value as an efficient method for producing such useful alkenylsuccinic anhydrides.

Claims (2)

[Claims] (1) A method for producing alkenylsuccinic anhydride, which comprises reacting an olefinic hydrocarbon and maleic anhydride in the presence of an aliphatic bromine compound having 10 to 24 carbon atoms. (2) The production method according to claim 1, wherein the aliphatic bromine compound having 10 to 24 carbon atoms is present in a ratio of 200 to 10,000 ppm (in terms of bromine amount) relative to the olefinic hydrocarbon.