JPS5945717B2 - Fatty acid production method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to fatty acids, and an object of the present invention is to industrially advantageously obtain fatty acids from alkaline fats and oils of animal and vegetable origin (hereinafter referred to as "fats").

Futs is a mixture of alkaline soap and glycerade and impurities, so it is necessary to obtain fatty acids (constituting alkaline soap and glycerade) in good quality and industrially advantageously. This is the company's evaluation.

Although many methods for obtaining fatty acids are known, these methods can be broadly classified into two.

The first method is to saponify the foot under normal pressure or increased pressure with the addition of an alkali, and then neutralize and decompose it using sulfuric acid (for example, JP-A-49-124103). Water is added to the so-called dark oil obtained by sumolysis, and the oil is hydrolyzed under pressure with or without a catalyst, or it is subjected to Teutzzer decomposition (for example, Yukagaku Vol. 19, No. 8, P, 808). All of these known methods have drawbacks.

According to the former method, too much alkali is used and a large amount of alkali neutralizing agent is required, and when the latter method is used, products made from the obtained fatty acids, such as cosmetic soaps, may be colored. Furthermore, the manufacturing process is complicated and production efficiency is low. The present invention does not have such drawbacks and will be described in detail below.

First, the starting material is foods.

As mentioned above, foots are the so-called dregs that are removed as a by-product during alkali refining of beef tallow, lard, rapeseed oil, soybean oil, cottonseed oil, sugar oil, corn oil, and other animal and vegetable oils and fats. The foots are placed under heat and pressure to hydrolyze the glycerade they contain to produce fatty acids and glycerin.

At this time, the pressure used may vary slightly depending on the origin of the fat or oil, but the pressure used may be approximately 7 to 35'/crlt, and the temperature may be approximately 1
The temperature may be 70 to 240°C. The reaction does not proceed at a temperature of about 170°C and a pressure of about 7, or below /CTlt, and at a temperature of about 240°C.
Above 35'/crlt, polyunsaturated fatty acids are altered,
Polymerization of fatty acids and other adverse effects occur. No catalysts such as alkalis are added to this reaction. This is the feature of this invention. A specific solvent and mineral acid are added to the mixed system of the produced fatty acids, glycerin, and residual sodium soap.

The feature of this invention is to specify the solvent.

Specifically, it refers to ketones (e.g. acetone, ME
K. ．． MIBKl is a homogeneous system consisting of 50 to 90% (by weight, the same applies hereafter) (methyl propyl ketone, diethyl ketone, etc.) and 50 to 10% C69 hydrocarbons (for example, benzene, toluene, xylene hexane, etc.). At this time, when the ketones content is less than 50%, separation of the fatty acid produced in the reaction-completed system from water containing mirabilite or common salt becomes insufficient, and when it is more than 90%, the purity of the obtained fatty acid becomes poor. However, use half or double the amount of solvent for the foots. A mineral acid such as sulfuric acid or hydrochloric acid is present in this system.

The amount used may be sufficient to bring the pH of the reaction system to 4 or less at the end of the reaction. In the reaction system, the mineral acid
It combines with Na in sodium soap to form mirabilite or common salt and is released from fatty acids. This treatment is carried out under normal pressure, about 60 to 75
The O reaction completion system, which is carried out at a temperature of , and on top of this, three layers of mirabilite, etc., fatty acids, solvents, and a mixture of impurities) are formed.

From this, only fatty acids are isolated using conventional methods.

This invention has now achieved its purpose. To explain the main functions and effects of this invention, the amount of soda and mineral acids used is much smaller than in the conventional method.

This is because the foots are decomposed as they are under pressure and heat, so there is no need for a saponification reaction like in conventional methods.The mineral acid is sufficient as the Na equivalent in the sodium soap present in the foots. It is. Since a mixed system of two solvents is used, when ketones are used alone (for example, Japanese Patent Publication No. 42-2764
7, 43-2718), the resulting fatty acid layer can be separated more clearly, and as a result, a target product with improved quality can be obtained.

Example 1 Glycerade 12.5(f), Sodium Soap 19.4
%, moisture and other 68.0% soybean food, 10
0 parts (weight, same below) in an autoclave at 180℃
- Hydrolysis was carried out by heating at 8Kf/0I for 3 hours.

The product contains 0.6% glycerade, 11.5% fatty acids,
It consisted of 19.4% sodium soap, 1.26% glycerin, and 67.2% other water. M for this thing
A mixed solvent consisting of 44.4 parts of EK and 8.6 parts of benzene is added.

Further, 8 parts of 70% sulfuric acid was added and stirred for 60 minutes at 7'C. The pH of the system was 3.5. When this was left at room temperature for 60 minutes, it was clearly separated into three layers: a solvent layer containing fatty acids, an intermediate layer, and a lower layer containing Glauber's salt and glycerin. The top layer was isolated and the solvent was evaporated from it to obtain 29.8 parts of crude fatty acids (98(!) fatty acids).

Example 2 300 parts of foods made from rapeseed oil were placed in an autoclave at 220°C and 24Kf/C! Hydrolysis was carried out by heating for 3 hours under t.

MIBKl benzene mixed solvent (85:15 ratio) to the product
195 parts and 179 parts of sulfuric acid were added and stirred at 70°C for 60 minutes. The pH of the system was 3.1. The system was clearly separated into three layers. The solvent was recovered from the upper layer liquid to obtain 93 parts of crude fatty acid. The quality of crude fatty acids is neutralization value 188.4, saponification value 1
The iodine value was 98.7 and the iodine value was 121.4 (decomposition rate 94.8%).

Claims (1)

[Claims] 1 Heat animal and vegetable oils and fats at about 170 to 240℃, about 7
~ Hydrolyzed to below 35Kg/cm^2, then approximately 60~
Approximately 50-90% of ketones and C_
A method for producing fatty acids characterized by adding a mixed solvent with about 50 to 10% of a hydrocarbon of 6 to _9 and a mineral acid having an amount equivalent to or more than the sodium content in foots to bring the pH of the system to 4 or less.