JPS62148448A - Storage of wet cake of sorbic acid - Google Patents

Abstract

PURPOSE:To provide a simple process for suppressing degradation of wet sorbic acid cake mixed with water and/or solvent and produced in a sorbic acid production process, by sealing the wet cake with an inert gas. CONSTITUTION:Wet sorbic acid cake mixed with water and/or solvent is sealed in a system having an oxygen concentration of <=15vol% by introducing an inert gas such as nitrogen, carbon dioxide, argon, etc., into the system. The method is remarkably effective in preventing color development and aging of an alkali metal sorbate produced by neutralization of sorbic acid. Sorbic acid has antimold action and is useful as an additive for preservation of foods.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for handling or preserving a sorbic acid wet cake produced in a sorbic acid manufacturing process.

Sorbic acid has an antifungal effect and is harmless, so it is often used as an additive for preserving prizes. Alkaline salts, such as sorbic acid potassium, have the same effect; while sorbic acid is poorly soluble in water, such alkali salts are easily soluble, so they are used depending on the purpose. Ru.

(Prior Art) Sorbic acid is produced by decomposing polyester obtained by reaction of crotonaldehyde and ketene. Decomposition methods include hydrochloric acid decomposition method, alkali decomposition method,
Among these methods, hydrochloric acid decomposition is known to be the most advantageous in terms of yield and quality because it does not involve the production of isomers. However, in either case, there is a problem in that a special purification step is required because tar by-produced during the reaction exists as an impurity along with the polyester residue. Furthermore, even with the comparatively superior hydrochloric acid decomposition method, this problem remains, and the citrusorbic acid obtained by cooling and filtering the polyester after decomposing it contains tar.

Conventionally, crude sorbic acid has been purified using an activated carbon treatment method, a recrystallization method using water or water + an organic solvent, and a method of dissolving it in petroleum and distilling it for purification. Research has been conducted on this purification method of crude sorbic acid for a long time, and currently, the above purification method alone,
Alternatively, high-grade sorbic acid has been obtained by a combination thereof.

(Problems to be Solved by the Invention) However, sorbic acid and the resulting alkali sorbic acid salt produced by the neutralization reaction of the sorbic acid deteriorate and become colored over time, especially when left in the atmosphere.
There is a tendency for the product value to decrease significantly.

(Means for Solving the Problems) The inventors of the present invention have conducted intensive studies in consideration of the drawbacks of the conventional methods described above, and have found that the sorbic acid wet cake produced in each manufacturing process is significantly altered in quality. I found out something easy. That is,
The wet cake is then led to a drying process or a norpine alkali salt production process, but the wet cake deteriorates even within a very short period of time (several hours). It should be noted that this deterioration of the wet cake is completely indistinguishable from its appearance, but surprisingly, when it is reacted with an alkali, or when the p II is subsequently adjusted to 10 or more: I was able to identify it.

Furthermore, if the wet cake of sorbic acid deteriorates, it goes without saying that even if an alkali salt of sorbic acid is produced by a neutralization reaction using the wet cake, the color will be inferior; It was also found that the hue deteriorated significantly over time.

On the other hand, attempts to remove the colored substances generated during the neutralization reaction by treatment with activated carbon, for example, have had no effect. Furthermore, even if the degraded wet cake of sorbic acid is dried as it is, it is possible to obtain sorbic acid with almost no change in appearance, but when the sorbic acid scissors are left in the atmosphere, it was found that the hue deteriorated significantly. .

The present inventors have conducted various studies on the deterioration of sorbic acid wet cake based on the above-mentioned various findings, and have discovered that such deterioration occurs only in the presence of oxygen, leading to the present invention. Ta. That is, the present invention provides a method for producing sorbic acid in which crude sorbic acid is purified,
This is a method for preserving a wet sorbic acid cake, which is characterized by sealing a wet sorbic acid cake mixed with water and/or a solvent with an inert residue.

It was found that water was the wet component of the sorbic acid wet cake that had the greatest effect on deterioration. A wet cake made of water alone or a mixture of water and solvent deteriorates drastically in the air, and even with only a solvent, it may be due to the influence of moisture in the air.
Somewhat mild alteration occurs.

Examples of the inert gas in the method of the present invention include nitrogen, carbon dioxide, and argon, but nitrogen is generally used in industrial equipment.

When sealing a wet cake by blowing in these inert gases, it is not necessary to adjust the oxygen concentration in the system.
By keeping the oxygen concentration below 15 parts by volume, preferably below 10 parts by volume, deterioration of the wet cake can be considerably suppressed.

Sorbic acid wet cake mixed with water and/or solvent is produced during the sorbic acid production process, and usually contains 50% or less water relative to sorbic acid.

In addition, when recrystallization is performed using methanol, ethanol, isopropyl alcohol, etc., these solvents replace 60% to 100% of the water content.

Examples of the alkali used in the neutralization reaction of sorbic acid include hydroxides, carbonates, bicarbonates, etc. of sodium and potassium. Preferably salt or salt.

(Effect of the invention) By adopting a very simple treatment method for preserving the wet cake produced in the sorbic acid production process, sorbic acid or an alkali sorbic acid salt produced by a neutralization reaction of the obtained sorbic acid can be produced. It was possible to significantly prevent the coloring from changing over time.

Example 1 100g of crude sorbic acid (20% water, 4% tar, 76% sorbic acid) obtained by hydrochloric acid decomposition method was dissolved in 5%
Dissolve in caustic soda aqueous solution and add activated carbon (white cedar
05 g (manufactured by Takeda Pharmaceutical Co., Ltd.) was added thereto, and the mixture was stirred for 30 minutes.

The treated solution was filtered, and an excess of 35% hydrochloric acid was added to the P solution to precipitate sorbic acid, followed by one filtration.

The sorbic acid cake was subjected to solvent reconsolidation using water to ethanol to obtain 90 g of purified sorbic acid wet cake (moisture 10%).
, ethanol 10%, sorbic acid 80%). The cake was left in a constant temperature room at 30° C. for one day and night while being completely sealed with nitrogen.

The color value of a solution prepared by dissolving the dried refined sorbic acid wet cake II in 1 Qrne of methanol before being left for one day was 95.0 when the transmittance of light at a wavelength of 350 μm was measured using a spectrophotometer. %, and when a dried seminal lupic acid wet cake after being left for one day and night was similarly measured, it was 95.0%.

1g of dried seminal lupic acid wet cake is 8.13
rat! When the color value of the solution dissolved in an aqueous solution of I N -Na0I-1 was determined by the transmittance of light at a wavelength of 400 μm, the cake before being left for 1 day and night was 960%, and after being left for 1 day and night, it was also 960%. .

Further, 33 g of water was added to 50 g of purified sorbic acid wet cake that had been left for 1 day and night, and a neutralization reaction was carried out with a 49% KOH aqueous solution. The potassium sorbate aqueous solution thus obtained was dried under reduced pressure (30 mmF (9.55°C)) to obtain 53 g of potassium sorbate.

The color value of the potassium sorbate was 97.0% when 2 g was dissolved in water to make 1011 g and the transmittance of the aqueous solution was measured spectrophotometrically at a wavelength of 430 μm. Further, when the potassium sorbate was air-sealed and left for 6 months, the color value was 94.0%.

Comparative Example 1 In the procedure of Example 1, the purified sorbic acid cake was left in the air for a day and night, and the color value of the solution dissolved in methanol was 94.0%, and the color value of the solution dissolved in 1N-NaOH aqueous solution was 94.0%. The color value decreased to 92.0%.

Potassium sorbate was obtained in the same manner as in Example 1 using a sorbic acid cake that had been left in the air for one day and night. The color value of the potassium sorbate was 96.0%. However, when the potassium sorbate was air-sealed and left for 6 months, the color value was 85.0%.

Example 2 Crude sorbic acid obtained by hydrochloric acid decomposition method 100! ?
(20% moisture, 4% tar, 76% sorbic acid),
Lubricating oil (commercially available) with a boiling point range of 200 to 250°C32
It was dissolved at 120°C with g. Pressure 30m of bath solution
It was heated and evaporated under the conditions of al19 until the can temperature reached 170°C.

After the natural air is purified using a filled mist separator, it is cooled and condensed using a contact condenser that circulates water.
It was collected as a mixed slurry of water, lubricating oil, and sorbic acid. When the slurry was passed through a 700g filter, 102g of a wet cake of pure sorbic acid (20% moisture, 10% lubricating oil, 70% sorbic acid) was obtained.The cake was completely sealed with nitrogen, It was left in a constant temperature room at ℃ for 1 day and night.

When the color value was measured in the same manner as in Example 1, the color value of the solution dissolved in methanol was 96.0% both before and after standing.
Met. Further, the color value when dissolved in the IN-N;TOII aqueous solution was 95.0% both before and after standing.

Also, add 33 liters of water to the Solvin cake 50 I which was left for one day and night.
．． 9 was added thereto, and a neutralization reaction was carried out using a 49% aqueous solution of KOI-1. After the lubricating oil component in the aqueous potassium sorbate solution obtained in this way was left to stand and separated and removed, activated carbon (Shirasugino) 19 was added and stirred for 30 minutes. The resulting aqueous solution was then dried under reduced pressure (30 mrn
(-1 g, 55°C), yielding 46 g of potassium chloride.

As the color value of the potassium sorbate, 2 g was dissolved in water to make 1Qml, and the transmittance of the water bath solution was measured with a spectroscopic needle at a wavelength of 430 μm, and it was found to be 98.0%. In addition, the potassium sorbate was air-sealed and 6
The color value when left for several months was 95.0%.

Comparative Example 2 In the procedure of Example 20, when the pure lupic acid wet cake was left in the atmosphere for about 10 hours, the color of the solution in methanol 11.1 became 94.5%, and I N -N a
The color values of the solutions dissolved in the 01-1 aqueous solution decreased to 900%.

Potassium sorbate was obtained in the same manner as in Example 1 using a purified sorbic acid wet cake that had been left in the atmosphere for about 10 hours.

The color value of the sorbin Lf, &potassium was 94.0%. Further, when the φlium sorbate was left in air for 6 months, the color image was 80.5%.

Procedural amendment, Ii (spontaneous) 1986
f3/-1/Z 11? ? I Correction Office Engineer Uga Michibe 1, Indication of Matter fl 1985 Special; [+ No. 2 J37903 No. 2, Title of Invention Method for Preserving Sorbic Acid Moisture-1-1-3, Person Making Amendment 1'1 and Relationship Special: 1' [Application location: 1 Teppo-cho, Sakai City, Osaka Prefecture Name (290) Daicel Chemical Industries, Ltd. 1 Representative name: Kubo Ill. 4, Agent: Kasumigaseki 3-chome, Chiyo I11-ku, Tokyo IE18- 1 Toranomon Mitsui Building Daicel Chemical Industries, Ltd. Patent Department Telephone (507) 324G・~8 Patent Attorney ↓ (9227) Takashi Koshiba 5, Column 6 for detailed explanation of the invention according to the specification to be amended, Contents of the amendment 1) Details; 1 (4th line from right below 9th r32tJJ to r3
i to 20 pJ; J rli? Jru.

2) Details; 1: 83rd Tei line 33 1” 1, page 9 line 5 [1
, page 10, line 10, day, J: and 11'Nj, line 11 [-
1 [lN-Na011 J is respectively "lN-Na0
II, rJ is correct.

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Claims (1)

[Claims] A method for preserving a wet sorbic acid cake, which comprises sealing the wet sorbic acid cake mixed with water and/or a solvent with an inert gas.