JPS5852989B2 - Monoglyceride sulfate compound - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides fatty acid monoglyceride sulfuric acid salts (7) alkali salts (hereinafter abbreviated as MGS).

), in detail, ■fatty acid monoglyceride (hereinafter referred to as M
Abbreviated as G.

) is sulfuric acid esterified with 5% to 20% fuming sulfuric acid.

MGS is a surfactant with excellent detergency, foaming power, and emulsifying power, and is useful as a soft detergent without the risk of pollution.

And its properties are significantly degraded by impurities, so
The highest possible purity is required.

Conventionally, MGS has been produced using three methods: (1) oil, glycerin, and sulfuric anhydride, oleum, or concentrated sulfuric acid, (2) fatty acids, glycerin, and concentrated sulfuric acid, and (3) MG and concentrated sulfuric acid. It was believed that a product with relatively good purity could be obtained by method (3) from MG purified by molecular distillation or the like.

However, in this case as well, unless concentrated sulfuric acid is used at least 8 times the theoretical amount, the yield will be poor and the scale of the reactor will become large. Mass production of high purity MGS has been completely impossible because the extremely unstable ester bonds are broken, and when large quantities are processed, hydrolysis proceeds to a large extent, and inorganic salts are easily mixed in.

As a result of intensive research, the present inventors have arrived at a method for overcoming this difficulty for the first time.

In other words, it eliminates both the disadvantage of having to use a large amount of sulfating agent with concentrated sulfuric acid and the disadvantage of coloring the reaction product with sulfuric anhydride, and uses 5% to 20% of fuming sulfuric acid to eliminate the disadvantage of using a large amount of sulfating agent. Sulfuric acid esterification can be carried out in good yield using the sulfating agent, and the heat of dilution when diluting the reaction solution can be significantly reduced, so even in mass production, we have succeeded in significantly preventing decomposition.

Furthermore, if a method is adopted in which the reaction solution is injected into water or water and butanol or (and) amyl alcohol, the fatty acid monoglyceride sulfate produced in the reaction will be transferred to the alcohol layer, and ester hydrolysis can be almost completely prevented. At the same time, separation from the sulfuric acid layer becomes extremely easy, and unreacted sulfuric acid can be completely removed from the alcohol layer by further washing with water if desired.

The separated sulfuric acid ester is mildly neutralized with the minimum necessary amount of alkali without fear of heat generation, and the target MGS can be obtained without contamination with impurities.

Undesirable hydrolysis of the ester did not occur at all, making mass production of highly pure MGS possible for the first time.

Fatty acids are those having 12 to 18 carbon atoms, singly or as a mixture, and alkalis include sodium, potassium, ammonium, and the like.

The amount of sulfuric anhydride in the fuming sulfuric acid is preferably 5% to 20%, and 5%
If it is less than 20%, the effect will be small, and if it is 20% or more, coloring or side reactions will easily occur.

The reaction temperature is about room temperature to 55°C, and the reaction time is about 30 minutes to 3 hours, although it varies depending on the humidity and stirring efficiency.

After the reaction is completed, it may be diluted with ice or water, and then extracted with phthanol residue or (and) amyl alcohol.
The reaction solution may be separated into a mixture of butanol or (and) amyl alcohol and water or ice while being cooled and stirred.

The alcohol used in the present invention has the general formula CnHOH (in the formula, n represents 4 or 5).

] 2n+1 alcohol, such as lobethyl alcohol, 1s
o-phthyl alcohol, 5ee-phthyl alcohol, 5
ec-amyl alcohol, 1so-amyl alcohol,
Examples include n-amyl alcohol, tert-amyl alcohol, etc., or a mixture of two or more thereof.

The desired MGS can be obtained by neutralizing the alcohol layer with alkali hydroxide or alkali carbonate, concentrating it to dryness, and washing it with an insoluble solvent such as methanol or acetone to adjust the crystal shape. can get.

Examples will be described below.

The parts indicated are parts by weight.

Example 1 100 parts of coconut oil fatty acid monoglyceride (content 82%) and 120 parts of 15% oleum are stirred and reacted at 40 to 45°C for 1 hour.

The reaction product is poured into 250 parts of ice and 200 parts of inbutanol under stirring at 20° C. or lower, and the isobutanol layer is separated.

Wash with 100 parts of water, neutralize with 30% caustic soda solution, and concentrate the inbutanol layer to dryness under reduced pressure.

250 parts of isobutanol is added to the residue for crystallization.

It was filtered and dried to obtain 95 parts of coconut oil fatty acid monoglyceride sulfate soda having a content of 98% and a soap content of 0.2%.

Comparative Example 1 A similar reaction was carried out using 125 parts of concentrated sulfuric acid instead of 120 parts of 15% oleum in Example 1, and the same treatment was performed, but the reaction rate was extremely poor, and the soap content was 90%. Only 60 parts of .5% coconut oil fatty acid monoglyceride sulfate soda were obtained.

Comparative Example 2 30 parts of 15% oleum in place of 120 parts in Example 1
When a similar reaction was carried out using 116 parts of oleum and treated in the same manner, the reaction solution was strongly colored and many by-products such as fatty acid soda were produced, resulting in a soap content of 89% and 0.
．． Only 78 parts of 2% brown coconut oil fatty acid monoglyceride sulfate soda was obtained.

Example 2 100 parts of coconut oil fatty acid monoglyceride (content 80%) and 200 parts of oleum are reacted with stirring at 45 to 50°C for 2 hours.

The reaction product is poured into 600 parts of ice, 50 parts of butanol, and 150 parts of pentyl alcohol at 20° C. or lower with stirring, and the alcohol layer is separated.

Wash twice with 100 parts of water, neutralize with 50% caustic soda, and concentrate to dryness under reduced pressure.

200 parts of acetone is added to the residue to crystallize it.

Filtered and dried, the content was 95.5% and the soap content was 0.1%.
Coconut oil fatty acid monoglyceride sulfate soda 9
I got 3 copies.

Example 3 100 parts of coconut oil fatty acid monoglyceride (80% content) and 200 parts of 10% oleum are reacted with stirring at 40 to 50°C for 2 hours.

The reaction product is poured into 500 parts of ice and 250 parts of isobutanol under stirring at 20°C or less, and the inbutanol layer is separated.

Wash with 100 parts of water, neutralize with 30% caustic soda solution, and concentrate the isobutanol layer to dryness under reduced pressure.

350 parts of acetone is added to the residue for crystallization.

After removing and drying, the content is 96.5% and the soap content is 0.1%.
Coconut oil fatty acid monoglyceride sulfate soda 9
Got 2 copies.

Claims (1)

[Claims] 1. A method for producing sulfates of fatty acid monoglycerides, which comprises sulfating fatty acid monoglycerides with 5% to 20% of oleum.