JPS6322797B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a treatment method for separating and recovering dicarboxylic acids from a fermentation liquid (culture liquid) containing long-chain dicarboxylic acids or long-chain oxycarboxylic acids (hereinafter referred to as dicarboxylic acids) obtained by a fermentation method. The dicarboxylic acids mentioned above are substances that are expected to have a wide range of uses as raw materials or sub-raw materials for manufacturing various chemical products such as pharmaceuticals, paints, resins, fragrances, lubricants, bleaches, surfactants, and agricultural chemicals, as well as as intermediates. be. In recent years, methods have been developed to produce such dicarboxylic acids by fermentation using normal paraffin and fatty acid esters as main raw materials and using microorganisms, such as JP-B No. 38-15608, JP-B No. 45-24392, JP-B No. 48-
26238, Special Publication Showa 50-19630 and Special Publication No. 56-44716
etc. have been proposed, and attempts are being made to implement them. In addition, as a method for separating, recovering or purifying dicarboxylic acids from the fermentation liquid containing the above-mentioned carboxylic acids obtained by the fermentation method, Japanese Patent Publication No. 28-6172 and Japanese Patent Application Laid-open No. 1983-1999 are disclosed.
15963, JP-A-56-15694, JP-A-56-15695, JP-A-55-24606, etc. have been proposed. Therefore, in order to separate and recover dicarboxylic acids from a fermentation liquid (fermentation broth) containing dicarboxylic acids obtained by a fermentation method, generally, after removing bacterial cells from the fermentation liquid in an alkaline region, (1) fermentation Add sulfuric acid or other mineral acids to the fermentation solution to precipitate and separate long-chain dicarboxylic acids in an acidic environment. (2) Form the dicarboxylic acids in the fermentation solution into water-insoluble salts such as calcium salts and precipitate them. (3) adding inorganic salts to the fermentation liquor and salting out the dicarboxylic acids as an alkali salt to separate them; (4) bringing the fermentation liquor into contact with an organic-inorganic salt to extract or dissolve the dicarboxylic acids. (5) separating dicarboxylic acids by treating the fermentation liquid with an ion exchange resin, etc. The present invention provides a method for dissolving and separating dicarboxylic acids from a fermentation liquor containing dicarboxylic acids obtained by a known fermentation method using an organic inorganic salt, in which dicarboxylic acids in the fermentation liquor are effectively dissolved in an organic solvent. An object of the present invention is to provide a method capable of separating and recovering dicarboxylic acids from a fermentation liquid in a high yield by separating the dicarboxylic acids and then precipitating them. The present inventor has discovered that the dicarboxylic acids in the fermentation liquid are dissolved in the mixed solvent by contacting the fermentation liquid (culture liquid) containing the dicarboxylic acids obtained by the fermentation method with two specific mixed solvents under heating. The present invention was achieved based on the knowledge that dicarboxylic acids can be effectively dissolved (extracted) and that dicarboxylic acids can be precipitated in high yield by subsequently cooling the mixed solvent. The present invention will be explained in detail below. A feature of the present invention is that 100 parts by volume of an aromatic hydrocarbon and 3 to 30 parts by volume of an oxygen-containing organic compound selected from the group consisting of alcohols, ketones, and aldehydes are added to the fermentation liquid containing the dicarboxylic acids or the treated liquid thereof.
A mixed solvent consisting of parts by volume is brought into contact with each other under heating to dissolve (extract) dicarboxylic acids into the mixed solvent,
The purpose is to separate and recover the resulting mixed solvent layer by cooling it to precipitate the dicarboxylic acids. The problems with the method of separating dicarboxylic acids from the fermentation liquor containing dicarboxylic acids using a solvent are as follows:
The solvent used can efficiently dissolve (extract) and precipitate dicarboxylic acids from a unit amount of fermentation liquor, be substantially insoluble in the fermentation liquor, and be free from being mixed in the fermentation liquor when the dicarboxylic acids are extracted. It is necessary to satisfy requirements such as that various raw materials, bacterial cells, by-products, etc., which are used in the production process, are difficult to extract into a solvent along with dicarboxylic acids. From the above-mentioned viewpoint, the present inventor investigated aromatic hydrocarbons such as toluene, xylene, ethylbenzene, etc. and other organic solvents, which are conventionally known to be used for the extraction of the above-mentioned dicarboxylic acids, and found that the above-mentioned aromatic When a mixture of a group hydrocarbon and an oxygen-containing organic compound selected from the group consisting of alcohols, ketones and aldehydes is used as a solvent, and this mixed solvent is brought into contact with the fermentation liquor under heating, the above requirements are met. I found out that I can get it. That is, the above mixed solvent is heated, preferably 70 to
When brought into contact with the above fermentation liquor under heating at 100°C, the ability to extract dicarboxylic acids from the fermentation liquor can be significantly improved compared to when aromatic hydrocarbons alone are used, and in addition, the amount of solvent used (fermentation liquor) is significantly improved. It is also possible to reduce the unit amount of solvent used relative to the content of dicarboxylic acids in the liquid. Furthermore, the quality of the recovered dicarboxylic acids can also be improved compared to when the oxygen-containing organic compound alone is used. Aromatic hydrocarbons used in the present invention include benzene, toluene, o-xylene, m-xylene,
Examples include p-xylene, ethylbenzene, trimethylbenzenes, propylbenzenes, and ethyltoluenes, and mixtures of two or more of these may be used. Moreover, the alcohol used in mixture with these aromatic hydrocarbons is preferably one having 4 or more carbon atoms in the molecule, such as butanol, isobutanol, pentanol, isopuntanol, hexanol, isohexanol, cyclohexanol. , heptanol, isoheptanol, octanol and isooctanol, and two or more of these may be used. Also, as a ketone,
Those having 4 or more carbon atoms in the same molecule are preferred, such as 2-butanone (methyl ethyl ketone),
Examples include 2-pentanone, 3-pentanone, 2-hexanone, 3-hexanone, 2-heptanone, 3-heptanone, 4-heptanone, and methyl isobutyl ketone (a compound in which a carbon atom has a side chain), and these two It may be a mixture of more than one species. Further, the aldehyde preferably has 6 or more carbon atoms in the same molecule, and examples include hexanal, heptanal, and octanal, and a mixture of two or more of these may be used. The mixed solvent used in the present invention is applied as a mixture consisting of 100 parts by volume of the aromatic hydrocarbon listed above and 2 to 40 parts by volume each of the alcohol, ketone or aldehyde listed above, preferably 3 to 30 parts by volume. . Incidentally, generally speaking, if more than 40 parts by volume of oxygen-containing compounds such as alcohols, ketones, or aldehydes are mixed into 100 parts by volume of an aromatic solvent, the solvent may be mixed into the fermentation liquor when dicarboxylic acids are extracted from the fermentation liquor. The amount of dicarboxylic acids dissipated by dissolution increases, and the amount of dicarboxylic acids precipitated during cooling decreases. On the other hand, if it is less than 2 parts by volume, the amount of dicarboxylic acids extracted into the solvent layer decreases, making it impractical. In the present invention, when the above-mentioned mixed solvent is brought into contact with the fermentation liquor, although it varies depending on the content of dicarboxylic acid in the fermentation liquor, the composition of the mixed solvent, the temperature at the time of contact, and the subsequent cooling temperature of the solvent layer, In general, the fermentation liquid (culture liquid) obtained by fermentation is used as it is, or the liquid obtained by removing bacterial cells and other insoluble matter from the fermentation liquid using an excessive method (referred to as a treated fermentation liquid) is used.
It is preferable to contact 30 to 200 parts by volume per 100 parts by volume. This contact may be carried out by any of the batch method, continuous method, straight flow method, counter current method, etc., and the method does not matter. Further, the contacting is preferably carried out under heating, usually at a temperature of 70 to 100°C. At this time, as the contact temperature decreases, the amount of dicarboxylic acids dissolved (extracted) in the mixed solvent decreases, while if it becomes too high, heat loss due to moisture or solvent evaporation increases, and the dicarboxylic acids are dissolved in the mixed solvent. No increase in the amount of solubility was observed. Note that as the temperature rises due to heating during the above-mentioned contact, there is a slight phenomenon in which a portion of the mixed solvent dissolves in the fermentation liquid layer, but the solvent layer is separated from the fermentation liquid layer by cooling after the above-mentioned contact. So there is no problem. In the present invention, the mixed solvent layer from which the dicarboxylic acids have been extracted will separate if left to stand after the above-mentioned contact.
When the solvent layer is separated from the fermentation liquor and then cooled, dicarboxylic acids precipitate out. During this cooling, the temperature is preferably 15 to 50°C, preferably 10 to 40°C lower than the temperature at the time of contact. The dicarboxylic acids precipitated in this way are separated and recovered using a solid-liquid separation method, and the mixed solvent obtained at this time is heated and circulated to contact with the fermentation liquid or its treatment liquid to repeatedly separate the dicarboxylic acids. Used for extraction. In addition, in the present invention, when the dicarboxylic acid-containing fermentation liquid (culture liquid) obtained by fermentation is brought into contact with the mixed solvent as is, bacterial cells are generally placed between the solvent layer from which the dicarboxylic acids have been extracted and the fermentation liquid layer. Since an emulsion layer containing the dicarboxylic acids is formed, it is necessary to remove the microbial cells from the emulsion layer by sand filtering or the like before cooling the solvent layer and dissolving the dicarboxylic acids. Next, for reference, the long chain dicarboxylic acids and long chain oxycarboxylic acids in the present invention will be explained. Long chain dicarboxylic acids have 10 or more carbon atoms, such as decanedioic acid, undecanedioic acid, dedecanedioic acid, etc. diacid, tridecanedioic acid (brassyl acid), tetradecanedioic acid, pentadecanedioic acid,
Saturated dicarboxylic acids such as hexadecanedioic acid (thapsic acid), heptadecenedioic acid, octadecanedioic acid and decenedioic acid, undecenedioic acid, dozecenedioic acid, tridecenedioic acid, tetradecenedioic acid, pentadecenedioic acid, hexadecenedioic acid, It includes unsaturated dicarboxylic acids such as octadecenedioic acid. Furthermore, long-chain dicarboxylic acids have 10 or more carbon atoms, such as ω-hydroxyalkanoic acid, ω-methoxyalkanoic acid, ω,ω-
These include 1-dihydroxyalkanoic acid and α-1-hydroxy-α,ω-alkanedioic acid. These long chain dicarboxylic acids and long chain oxycarboxylic acids are, for example,
It is advantageously produced by a fermentation method according to the method disclosed in the publication. As described above, according to the present invention, it is possible to very efficiently separate and recover long-chain dicarboxylic acids or long-chain oxycarboxylic acids using a solvent from a fermentation liquid containing long-chain dicarboxylic acids or long-chain oxycarboxylic acids obtained by a fermentation method, or from a treated liquid thereof. become able to. EXAMPLES The present invention and its effects will be specifically explained below with reference to Examples. In addition, % in each example represents weight unless otherwise specified. The fermentation liquid containing long-chain dicarboxylic acid in this example was produced according to the method described in Japanese Patent Publication No. 56-44716. Example 1 BR belonging to Candida tropicalis
A 2N-NaOH aqueous solution was added to the fermentation liquid containing tridecanedioic acid obtained by fermenting normal paraffin using the 254 strain (see Japanese Patent Publication No. 56-44716) to adjust the pH to 11, and after separating the bacterial cells, the 2N -H ₂ SO ₄ aqueous solution was added to prepare 250 ml of a slurry liquid (tridecanedioic acid content: approximately 98 g/) with a pH of 3.5. 100 ml of a mixture of 83.4 ml of ethylbenzene and 16.6 ml of 1-hexanal was added to 250 ml of the slurry, mixed and brought into contact with each other under stirring at 80°C, and the resulting supernatant liquid (solvent layer) was separated. After separating the suspended matter contained in the supernatant at 80°C, cooling to 40°C and standing still, the formed solid was separated, washed with n-pentane, and dried and weighed to obtain 17.3 g of solid. A portion of this solid was methyl esterified and measured by gas chromatography, and the purity was found to be 98.9%. The protein content in the solid material was measured by the Lawry method (cow serum albumin equivalent) and was found to be less than 0.01%. For comparison, 100 ml of ethylbenzene and 100 ml of 1-hexanal were added to each 250 ml of the slurry liquid prepared in the same manner as above.
When the same operation was carried out by adding ml of each separately, the yields of solid matter were 4.5 g and 13.9 g, respectively. The purity of tridecanedioic acid in each solid by gas chromatography is 98.9% and 99.0%.
%, and the protein content is 0.01% or less and 0.27
It was %. Furthermore, for comparison, when 250 ml of the slurry liquid prepared in the same manner as described above was directly washed with separately distilled water, the yield of solid matter was 23.9 g, the purity of tridecanedioic acid in the solid matter was 96.5%, and the protein content was
It was 0.67%. As mentioned above, when a solvent is used alone, the yield of tridecanedioic acid in the fermentation broth is low, while when no solvent is used, the purity of tridecanedioic acid is low. Furthermore, when the above mixed solvent is used, the yield and quality of tridecanedioic acid are superior to those when a single solvent is used. Example 2 Ethylbenzene was added to each of 100 ml of a slurry containing tridecanedioic acid prepared in the same manner as in Example 1.
A mixture of 56 ml and 4 ml of 1-hexanol and a mixture of 57 ml of ethylbenzene and 3 ml of 1-hexanol were added and stirred at 80°C. The supernatants were separated and cooled to 40°C, followed by the same procedure as in Example 1. As a result of collecting the solid matter, the purity was 98.7%, and the protein content was 98.7%.
8.7 g of 0.01% tridecanedioic acid and 98.6% purity,
8.9 of tridecanedioic acid with a protein content of 0.01% were obtained, respectively. Next, for comparison, 40 ml and 160 ml of ethylbenzene were individually added to 100 ml of the slurry containing tridecanedioic acid obtained in the same manner as above, and the mixture was heated to 80°C.
After stirring, the supernatant liquid was separated and cooled to 40° C., and solid matter was recovered in the same manner as in Example 1. As a result, the yields of solid matter were 1.8 g and 7.5 g, respectively. As seen in the above example, ethylbenzene and 1-
When a mixture with hexanol is used as a solvent, the yield of tridecanedioic acid is significantly improved compared to when these are used alone. Example 3 After adjusting 100 ml of a sterilized fermented liquid containing about 110 g of tridecanedioic acid to pH 3.0, it was mixed with a mixture of 41.7 ml of ethylbenzene and 8.3 ml of 2-hexanone at 80°C and stirred. After separating the clear layer, 40℃
The solid content obtained by cooling was separated, washed, dried, and weighed to obtain 10.3 g of solid content. Next, for comparison, after adjusting the pH to 3.0, 50 ml of ethylbenzene and 50 ml of 2-hexanone were added to each of 100 ml of the sterilized fermented liquid obtained in the same manner as above, and the solid content was obtained by the same procedure as above. Ta. The yields of each solid content were 2.1 g and 7.9 g, respectively. Also, after adjusting the pH to 3.0, add 54.6 ml of ethylbenzene to each 100 ml of the sterilized fermented liquid obtained as described above.
A mixed solution consisting of 2-hexanone (5.4 ml) and 60 ml of ethylbenzene alone were added to obtain a solid content in the same manner as above. The yields of each solid were 10.4 g and 2.3 g, respectively. The purity of tridecanedioic acid in each of the solid components was 98.8% to 99.0%, and the protein content was 0.01% or less in all cases except for 2-hexanone. 2-hexanone alone was 0.12%. As seen in the example above, ethylbenzene and 2
- When a mixture with hexanone is used as a solvent, the yield of tridecanedioic acid is significantly higher than when these are used alone. Example 4 After adjusting the pH of 100 ml of a sterilized fermented liquid containing about 110 g of tridecanedioic acid to 3.0, it was heated at 80°C for 1,3 hours.
33.4ml of 5-trimethylbenzene and 1-pentanol
The supernatant obtained by mixing and stirring with 6.6 ml of a mixed solution was separated, cooled to 40°C, the resulting solid content was separated, washed and dried, and then weighed, and the result was 9.0 g. In addition, 45.5 ml of 1,3,5 trimethylbenzene and 1-
When using a mixed solution of 4.5 ml of bentanol and 50 ml of 1,3,5-trimethylbenzene alone, the solid yields obtained were 9.7 g and 2.7 g, respectively.
It was hot. Example 5 Fermentation liquid obtained by fermenting tetradecene-1 as a substrate under aerobic conditions was sterilized at PH11, and then PH was adjusted with sulfuric acid.
1,3,5- to 100ml of slurry liquid adjusted to 4.0.
60ml of trimethylbenzene and 6ml of 1-hexanol
The mixture consisting of the following was mixed under stirring at 80°C, left to stand, the resulting supernatant layer was separated, cooled to 60°C, the precipitated solid content was separated, washed, and weighed. The yield was 3.4g. Ta. 200mg of this solid was separated, dissolved in ether, methylated, trimethylsilylated, and analyzed by gas chromatography.
13,14-dihydroxytetradecanoic acid 62.4%, tetradecanedioic acid 13.4%, 14-methoxytetradecanoic acid 9.9%, 14-hydroxytetradecanoic acid 6.8%
%, 13-hydroxytetradecanedioic acid 5.3%, and other 2.2%. Using 40 ml of the solution after separating the precipitated solids (the above mixed solvent), 60 mL of the same slurry solution as above was used.
ml at 80°C and separate the resulting supernatant layer at 60°C.
As a result, 2.4 g of solid content was obtained. Example 6 A sterilized fermented liquid (PH
Add various solvents shown in the table below to each solution in 3.5).
They were brought into contact at a temperature of 80°C, the resulting solvent layer was separated, and then cooled to 40°C to precipitate the solid content of pentadecanedioic acid. The yield of each solid content is shown in the table below.

[Table] As seen in the above table, when a mixed solvent is used according to the present invention, compared to when a solvent alone is used,
The yield of pentadecanedioic acid is improved.

Claims (1)

[Scope of Claims] 1. In separating and recovering the above-mentioned carboxylic acids from a fermentation liquid containing long-chain dicarboxylic acids or long-chain oxycarboxylic acids obtained by a fermentation method, or a treated liquid thereof, the fermentation liquid or its treated liquid contains: aromatic hydrocarbons
100 parts by volume and 3 oxygen-containing organic compounds selected from the group consisting of alcohols, ketones and aldehydes.
The dicarboxylic acids were dissolved (extracted) in the mixed solvent by contacting with a mixed solvent consisting of 30 parts by volume under heating, and the resulting solvent layer was separated and cooled to precipitate the dicarboxylic acids. A method for treating a fermentation liquid containing long-chain dicarboxylic acids or long-chain oxycarboxylic acids, which comprises separating and recovering dicarboxylic acids. 2. The treatment method according to claim 1, wherein the oxygen-containing organic compound is an alcohol having 4 or more carbon atoms. 3. The treatment method according to claim 1, wherein the oxygen-containing organic compound is a ketone having 4 or more carbon atoms. 4. The treatment method according to claim 1, wherein the oxygen-containing organic compound is an aldehyde having 6 or more carbon atoms. 5. The treatment method according to claim 1, wherein the mixed solvent is brought into contact with the fermentation liquid or its treatment liquid at a temperature of 70 to 100°C. 6. The mixed solvent layer produced by contacting the above fermentation liquid or its treated liquid with the above mixed solvent is heated to a temperature of 10% above the contact temperature.
Claim 1 of cooling to a temperature lower than 50°C
or the treatment method described in paragraph 5. 7. The treatment method according to claim 1, wherein the liquid after separating and recovering the precipitated dicarboxylic acids is recycled as a mixed solvent for contact with the fermentation liquid or its treatment liquid.