JPS63165339A - Production of saturated fatty acid - Google Patents

Abstract

PURPOSE:To efficiently produce a saturated fatty acid having two less carbon atoms than those of a fatty acid part of a raw material, by mixing a mixed ester of unsaturated and saturated fatty acids with a specific amount of an acid and hydrogen peroxide and using a simple apparatus under mild condition. CONSTITUTION:1-50pts.wt., preferably 10-30pts.wt. acid, particularly preferably sulfuric acid or alkylbenzenesulfonic acid and hydrogen peroxide in an amount of 0.1-10pts.wt., preferably 0.2-5pts.wt. expressed in terms of 100% H2O2 are added to 100pts.wt. esterification product of an 8-30C mixed fatty acid of unsaturated and saturated fatty acids, e.g. palm oil fatty acid, beef tallow fatty acid, coconut fatty acid, etc., with a 1-8C alcohol, e.g. mono- or polyhydric alcohol and reacted at 20-100 deg.C to cleave the carbon chain of the fatty acid part in the fatty acid esters between the second and the third carbon bonds from the alkyl group terminal and afford the aimed fatty acid. This method is safe without energy loss.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a method for producing a saturated fatty acid whose fatty acid moiety has two fewer carbon atoms than the unsaturated fatty acid ester that is the starting material by performing extremely simple processing. It is related to.

[Conventional technology]

The Barren Trap reaction is known as a method for producing straight-chain saturated fatty acids that have two fewer carbon atoms than the straight-chain unsaturated fatty acids that are the starting material (Ack? 7 (R, G,
ACKMAN et al), Tetrahedoro 7 (
Tetra hedron) Vol 8. P221
~238 (1960)). In this method, a strong alkali such as molten potassium hydroxide is used, and the
Unsaturated fatty acids are treated at a high temperature of 0 to 380° C. for 1 to 5 hours to decompose the fatty acids into saturated fatty acids with two fewer carbon atoms and acetic acid. This method is said to be able to produce saturated fatty acids in high yields, but because the reaction is carried out under strong alkali and high temperature pressure, the equipment becomes larger and more complex, and there are safety issues. There was also the problem that it was not economical from an energy balance standpoint.

[Problem that the invention seeks to solve]

Therefore, an object of the present invention is to provide a method for efficiently producing saturated fatty acids from unsaturated and saturated mixed fatty acid esters under mild conditions and using a simple device.

[Means for solving problems]

In the present invention, by simply mixing an unsaturated and saturated mixed fatty acid ester with a specific amount of acid and hydrogen peroxide, the carbon chain of the unsaturated fatty acid ester part in the raw material can be easily cut, and the fatty acid part of the raw material can be easily cut. This was based on the knowledge that a saturated fatty acid with two fewer carbon atoms can be obtained.

That is, the present invention uses unsaturated carbon atoms having 8 to 30 carbon atoms.

1 to 50 parts by weight of acid and 0.1 to 10 parts by weight of hydrogen peroxide are added to 100 parts by weight of an esterified product of a saturated mixed fatty acid and an alcohol having 1 to 8 carbon atoms, and the mixture is reacted at 20 to 100°C. To provide a method for producing a saturated fatty acid, characterized in that a saturated fatty acid having two fewer carbon atoms than the fatty acid part of a saturated fatty acid ester is obtained.

The fatty acid moiety of the unsaturated and saturated mixed fatty acid ester to be treated in the present invention has 8 to 30 carbon atoms, preferably 10 to 20 carbon atoms, and has at least one unsaturated bond in the molecule, preferably one Examples include unsaturated and saturated mixed fatty acids having ~3 fatty acids, and it is particularly preferable to use linear unsaturated and saturated mixed fatty acids. In addition, as the esterified product of the unsaturated and saturated mixed fatty acids and alcohol,
Esterified product with alcohol, ethylene glycol,
Examples include mono- or di-esterified products with dihydric alcohols such as propylene glycol, mono-, di-, or triesters with glycerin, and partial or total esterified products with polyhydric alcohols such as pentaerythritol and sorbitan. Specifically, esters of natural fatty acids such as palm fatty acid, beef tallow fatty acid, and coconut fatty acid with monohydric alcohols and polyhydric alcohols are exemplified.

Among these, although the reason is unknown, by mixing saturated fatty acid ester with unsaturated fatty acid ester, the overall IV (
When a raw material with an iodine value of 0.6 to 50, preferably 0.6 to 30 is used, the reaction is gentle and saturated fatty acids can be obtained from unsaturated fatty acid esters in high yield. .

At this time, as the saturated fatty acid ester to be mixed,
It is advantageous to use a fatty acid ester having two fewer carbon atoms than the unsaturated fatty acid ester, since a fatty acid with a single chain length can be obtained.

In the present invention, the above-mentioned unsaturated and saturated mixed fatty acid ester 10
0 parts by weight, 1 to 50 parts by weight of acid (hereinafter abbreviated as parts), preferably 10 to 30 parts, and 10 parts of hydrogen peroxide.
As 0% hydrogen peroxide, 0.1 to 10 parts, preferably 0
．． Add 2-5 parts.

The acids used here include inorganic acids such as sulfuric acid, phosphoric acid, and hydrochloric acid, benzenesulfonic acid, and alkyl groups with 1 to 1 carbon atoms.
Organic acids such as 14 alkylbenzenesulfonic acids can be mentioned. Among these, preferred acids are sulfuric acid,
It is an alkylbenzene sulfonic acid.

In the present invention, the above-mentioned components are added and mixed to cleave the carbon chain of the fatty acid moiety in the fatty acid ester between the second and third carbon bonds from the end of the alkyl group. At this time, mix 2
0 to 100°C, preferably 40 to 80°C, 10 minutes to 2
It is desirable to carry out the treatment for a period of time, preferably 30 minutes to 1 hour. In other words, if the reaction is carried out at a temperature below 20°C, the reaction will hardly proceed and the target saturated fatty acid will not be obtained.On the other hand, if the reaction is carried out at a temperature exceeding 100°C, the resulting saturated fatty acid will deteriorate in color and odor, which is undesirable. .

〔Effect of the invention〕

According to the present invention, saturated fatty acids having two fewer carbon atoms than the raw unsaturated fatty acid ester can be produced by an extremely simple method without problems such as enlargement of equipment, complexity, safety, and energy loss. can be manufactured.

Furthermore, by changing the addition ratio of acid/hydrogen peroxide, the ratio of saturated/unsaturated fatty acids and esters can be easily and freely controlled, making it easy to obtain fats and oils with the desired properties. Basic properties such as penetration power, foaming power, and rinsability can be easily adjusted, and the fatty acids and esterified products thereof produced according to the present invention can be expected to be widely used in many fields such as the detergent industry. In particular, detergent raw materials with an IV of 3 or less are preferred;
Such a product can be easily manufactured according to the present invention.

Next, the present invention will be explained by examples, but the present invention is not limited thereto.

〔Example〕

Example 1 59 g of methyl oleate (IV = 84) and 94 g of methyl stearate (IV < 0.1)
Put 1g in a mixing container of 21 and add 35%) 120
35 g of a and 50 g of concentrated sulfuric acid were added and mixed at a temperature of 80° C. for about 1 hour with stirring. Next, the obtained mixture was left to stand and separated, and the oil layer was washed with hot water. Then, water was removed by topping, and then the mixture was dehydrated to obtain the desired linear saturated fatty acid and its ester.

The IV of the main product was measured by the Rice method and was reduced to 0.3, and further measured by the GC method showed that 4 mol% of valmitic acid was produced (yield based on oleic acid methyl ester was 80%).

Example 2 The mixture ratios of oleic acid methyl ester and stearic acid methyl ester used in Example 1 were varied, and an acid and hydrogen peroxide were added to carry out a reaction. The reaction conditions and results are summarized in Table-1. Note that the amounts of acid and hydrogen peroxide added in the table are parts by weight per 100 parts by weight of the raw material ester.

Further, the yield was expressed as the amount (%) of valmitic acid produced relative to the reduced methylnystyl oleate.

From the results shown in Table 1, according to the present invention, oleic acid ester can be converted into valmitic acid having two fewer carbon atoms in good yield.

Claims (2)

[Claims] (1) 1 to 50 parts by weight of acid and 0.1 to 10 parts by weight of hydrogen peroxide per 100 parts by weight of an esterified product of an unsaturated or saturated mixed fatty acid having 8 to 30 carbon atoms and an alcohol having 1 to 8 carbon atoms A method for producing a saturated fatty acid, which comprises adding and reacting at 20 to 100°C to obtain a saturated fatty acid having two fewer carbon atoms than the fatty acid part of the unsaturated fatty acid ester. (2) The manufacturing method according to claim (1), wherein the alcohol is a monohydric alcohol or a polyhydric alcohol.