JPH0138A - How to recover resorcinol - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for recovering resorcinol, and more specifically to a method for recovering m-diisopropylbenzene.
- A method for purifying and recovering resorcin from acid decomposition products of diisopropylbenzene dihydroperoxide.

Technical Background of the Invention and Meanwhile, m-diisopropylbenzene (hereinafter sometimes abbreviated as m-DIPB) is oxidized with molecular oxygen in the presence of a base to produce m-diisopropylbenzene dihydroperoxide (hereinafter referred to as III). -DHP) is obtained, and it is well known that resorcinol and acetone can be obtained by acid decomposition of this m-DHP.

In addition, m-DHP obtained by oxidation of m-DIPS
When acid decomposing oxidation reaction products containing
- A method of extracting DHP and decomposing it with acid is also known. In order to improve the conversion rate of Zara III-DIPB to m-DHP, a method of adding hydrogen peroxide solution to the oxidation reaction product of m-DIPB to oxidize Zara is also known. Publication No. 53-23939, Japanese Unexamined Patent Publication No. 59-141
530, Japanese Patent Publication No. 60-3290, and British Patent No. 910735).

By the way, m-D which is 1q by oxidation of m-DIPB
When the oxidation reaction product containing HP is decomposed with acid, in addition to the production of resorcinol and acetone, m-isopropylphenol and the like are produced as by-products.
Olefins such as m-isopropenylphenol, m
-Hydroxy-α,α-dimethylbenzylal]-carbinols, m-hydroxyacetophenone,
Ketones and high boilers such as m-isopropylacetophenone are also produced.

By the way, it is also known that after acetone and a water-insoluble solvent are distilled off from the acid-decomposed mixture thus obtained, water is added to separate the resorcinol.

The conventional method for recovering resorcin from an acid-decomposed mixture is to remove acetone and water in a deacetone tower and a dehydration tower, respectively, and then remove the water-insoluble solvent in a desolvation tower, and then to a resorcin recovery tower. A method of distilling resorcinol is known. However, in this type of conventional distillation method, the acid decomposition reaction mixture is exposed to high temperatures in the steaming tower, resulting in the formation of high-boiling condensates such as the reaction of resorcin with olefins and carbinols. Therefore, there is a loss of resorcin and the recovery rate of resorcin becomes low, and when purifying resorcin by distillation, the mixture is thermally decomposed and impurities are mixed into resorcin, so there is a problem that resorcin cannot be obtained in high purity. .

1. The present invention is an attempt to solve the problems associated with the prior art as described above, and the present invention aims to solve the problems associated with the prior art as described above. The object of the present invention is to provide a method for purifying and recovering resorcin, which allows highly purified resorcin to be recovered at a high recovery rate from a product.

The method for recovering resorcinol according to the present invention is a method for recovering resorcinol obtained by oxidizing m-diisopropylbenzene with molecular oxygen.
- An oxidation product containing diisopropylbenzene dihydroberoxide is acid-decomposed with an acid catalyst in the presence of an aromatic hydrocarbon, and acetone is distilled off to remove 1 q of acetone. 100 of aromatic hydrocarbon solvents
At least one compound selected from the group consisting of monohydric phenols, nitriles, cyclic ether compounds, and water-insoluble dialkyl ketones is added in an amount of 5 parts by weight or more per part by weight, and two liquid phases are added. The method is characterized in that the residue of the deacetone can is separated into oil and water in the presence of a sufficient amount of water to form a resorcinol, and resorcinol is recovered from the resulting aqueous phase.

Hereinafter, the method for recovering resorcinol according to the present invention will be explained in detail.

By oxidizing m-diisopropylbenzene (m-DIPB>), diisopropylbenzene dihydroperoxide (
As a method for producing m-DHP, a wide variety of conventionally known methods can be employed. Usually m-
DIPB may be oxidized with molecular oxygen, such as air, in the presence of a base, optionally using a radical initiator.

When m-DIPB is oxidized in this way, as by-products of the oxidation reaction, m-diisopropylbenzene monocarbinol monohydroberoxide (m-HHP), m
-diisopropylbenzenedicarbinol (m-DC)
, m-diisopropylbenzene dihydroberoxide (
m-MHP> etc.

In the present invention, these oxidation products are acid-decomposed using an acid catalyst in the presence of an aromatic hydrocarbon solvent.

In this case, after addition of the solvent, acid decomposition may be performed as is, or
If necessary, hydroperoxides are extracted from the oxide of m-DIPB using NaOH water, neutralized with CO2, and then redissolved in an aromatic hydrocarbon solvent to improve the purity of m-DHP. May be decomposed or m-HH
Carbinols such as P and m-DC may be oxidized with hydrogen peroxide to form m-DHP, which may be acid-decomposed.

Furthermore, if necessary, part of the solvent may be removed by distillation or the like to increase the concentration of the oxide, and then acid decomposition may be performed.

In the present invention, the oxidation product containing m-DHP obtained as described above is subjected to an acid decomposition reaction of m-DHP using an acid catalyst in the presence of an aromatic hydrocarbon solvent. As the acid decomposition reaction conditions at this time, conventionally known conditions are employed.

Examples of the aromatic hydrocarbon solvent used include benzene, toluene, xylene, ethylbenzene, cumene, cymene, and diisopropylbenzene, among which toluene is particularly preferred.

In addition, acid catalysts used in acid decomposition reactions include inorganic acids such as sulfuric acid, hydrochloric acid, and phosphoric acid, strong acidic ion exchange resins, solid acids such as silica alumina, chloroacetic acid, methanesulfonic acid, and benzenesulfonic acid. Acids, heteropolyacids such as phosphotungstic acid, phosphomolybdic acid, etc. are used.

In any case, conventionally known conditions can be employed as a method for producing this acid-decomposed mixture.

In the acid decomposition mixture obtained in this way, in addition to the target compound resorcin, acetone, and the aromatic hydrocarbon solvent, byproduct water during acid decomposition and the acid used in acid decomposition are dissolved in an alkaline aqueous solution. In addition to m-isopropylphenol, reaction by-products include olefins such as m-isopropenylphenol, and carbinol such as -hydroxy-α and α-dimethylbenzyl alcohol. class, m-hydroxyacetophenone, m-i-sopropylacetophenone, 4-ri3-
hydroxycumyl) resorcinol [sometimes abbreviated as CP-R3].

In the present invention, the acid catalyst is usually removed from the acid decomposition mixture by filtration or the like when a solid acid is used, or by neutralization with an alkali when a liquid acid is used), Furthermore, monohydric phenols, nitriles, cyclic ether compounds, and water-insoluble dialkyl ketone groups were added to the deacetonization can residue obtained by distilling off the acetone, per 100 parts by weight of the aromatic hydrocarbon solvent contained therein. At least one compound selected from the following is added in an amount of 5 parts by weight or more, and in the presence of a sufficient amount of water to form two liquid phases, oil and water separation of the deacetone can residue is carried out. It is done. In the present invention, the amount of water sufficient to form two liquid phases when separating oil and water from the residue of the deacetone can is defined as:
Specifically, the water concentration in the deacetone canister residue is usually 5 to 5.
80@fi%, preferably in the range of 15 to 60% by weight. In addition, if the acetone content in the deacetone can residue is too high, the oil-water characteristics will deteriorate, so the acetone concentration in the deacetone can residue is usually 0 to 30% by weight, preferably 0 to 10% by weight. It is desirable that it be within the range. The method of adjusting the water concentration and acetone concentration in the deacetonization can residue during oil-water separation to the above range is to remove acetone by distilling the acid decomposition mixture as appropriate, and adding water or removing it by distillation as necessary. The concentrations of water and acetone can be brought into the above range by a method such as .

Specifically, the monohydric phenols used in the present invention include phenol, m or cresol, m or p-
Examples include alkylphenols such as ethylphenol, m- or iso-butylphenol, alkenylphenols such as m- or p-vinylphenol, and m- or p-isopropenylphenol, among which toisopropylphenol or m-isopropenylphenol is used. preferable.

Specific examples of the nitriles include acetonitrile, propionitrile, acrylonitrile, benzonitrile, etc. Among these, acetonitrile is particularly preferred.

Specifically, the cyclic ether compound includes dioxane,
Examples include tetrahydrofuran, among which dioxane is preferred.

Specific examples of water-insoluble dialkyl ketones include methyl propyl ketone, methyl isobutyl ketone (MIBK>, diethyl ketone, diisopropyl ketone, ethyl isopropyl ketone, propyl butyl ketone, diisobutyl ketone, amyl butyl ketone, etc.) having 5 to 10 carbon atoms. For example, MIBK is preferable.

In the present invention, if at the time of oil-water separation, at least one compound selected from the group of monohydric phenols, nitriles, cyclic ether compounds, and water-insoluble dialkyl ketones is added per 100 parts by weight of the aromatic hydrocarbon solvent in the deacetone can residue.
If the amount of the seed compound is less than 5 parts by weight, the oil phase and aqueous phase cannot be separated sufficiently, and in many cases, a tar phase containing a large amount of high-boiling impurities dissolves in addition to the oil and aqueous phases. It appears and becomes three phases. For this reason, it is difficult to successfully separate the aqueous phase that contains the target compound, resorcinol, and even if the aqueous phase is separated, the resorcinol obtained from this aqueous phase has low purity and the recovery rate is low. It ends up.

In the present invention, the amount of at least one compound selected from the group of monohydric phenols, nitriles, cyclic ether compounds, and water-insoluble dialkyl ketones added to the deacetonization can residue during oil-water separation is controlled. There is no particular restriction on the upper limit, but it is usually set to 100 parts by weight or less for economical reasons.

Based on the above, in the present invention, when separating an acid-decomposed mixture consisting of an oil phase and an aqueous phase into oil and water, a compound selected from the group of monohydric phenols, nitriles, cyclic ether compounds, and water-insoluble dialkyl ketones in the mixture is The ω of at least one compound is adjusted to the range described above.

Although the residue of the deacetonization tank originally contains m-isopropylphenol and m-isopropenylphenol as reaction by-products of acid decomposition, the amount of these is usually small, and Since the amount is less than 5 parts by weight per 100 parts by weight, in the present invention, monohydric phenols such as m-isopropylphenol and m-isopropenylphenol are usually added to the residue of the deacetone can within the range specified above. After addition, oil-water separation is performed. However, if monohydric phenol is contained in the deacetonization can residue in an amount of 5 parts by weight or more per 100 parts by weight of the aromatic hydrocarbon solvent, the monohydric phenol is removed from the deacetonization can residue. The oil and water separation may be carried out without adding it to the liquid.

Regarding the cyclic ether compound, the appropriate amount of acetone is distilled off so that the amount falls within the above range, and the cyclic ether compound is added to the residue of the deacetonization tank consisting of an oil phase and an aqueous phase, and then the cyclic ether compound is added to the above range. Oil/water separation is performed.

On the other hand, regarding the water-insoluble dialkyl ketone, the water-insoluble dialkyl ketone may be added to the deacetone can residue during oil/water separation in an amount within the above range, or the above-mentioned aromatic In addition to the group hydrocarbon solvent, this water-insoluble dialkyl ketone may be used in combination, and oil-water separation is carried out in this manner.

Regarding nitriles, nitriles may be added to the deacetonization can residue in the above range during oil/water separation, or the aromatic hydrocarbon solvent may be added to the solvent used in the acid decomposition described above. Other nitriles may be used in combination, and oil-water separation is performed in this way.

In the present invention, during oil-water separation, resorcin is efficiently extracted into the water phase and other by-products are efficiently extracted into the oil phase, and then highly purified resorcin is obtained from the water phase. In order to reduce the by-products remaining in the aqueous phase, by roughly extracting them with a solvent, resorcinol of even higher purity can be obtained. The solvent used in this case is
The aromatic hydrocarbon, a mixture of aromatic hydrocarbon and monohydric phenols, a mixture of aromatic hydrocarbon and nitriles, a mixture of aromatic hydrocarbon and cyclic ether compound, aromatic hydrocarbon and water-insoluble Examples include a mixture of dialkyl ketones. At this time, it is even more effective if a countercurrent multistage extraction method is used.

In the present invention, oil/water separation is usually carried out at a temperature range of 0 to 110°C, preferably 30 to 100°C. Resorcinol is recovered from the separated aqueous phase by an appropriate method similar to conventional methods, for example, by distilling the separated aqueous phase to separate resorcinol.

In addition, in the present invention, in order to recover resorcin from the oil phase separated from oil and water, the oil phase is extracted with water, and after the solvent is removed in a colander and the resorcin is produced by tartaring, m- DIRB! If it is returned to the acid decomposition product of the compound, resorcinol can be recovered at a much higher recovery rate.

In addition, FIG. 1 shows a flowchart diagram illustrating the resorcinol recovery method according to the present invention.

Effects of the Invention According to the resorcinol recovery method of the present invention, oil and water can be efficiently separated from an acid-decomposed mixture consisting of an oil phase and an aqueous phase, and by-products (for example, 4-(
The phase-separated method of the present invention can reduce the proportion of impurities such as 3-hydroxycumyl (resorcinol) extracted into the aqueous phase and increase the proportion of resorcinol extracted into the aqueous phase. Highly purified resorcinol can be recovered from the aqueous phase at a high recovery rate.

The method of the present invention will be specifically explained below using examples.

Examples 1 to 10 The base was removed from the oxidation reaction mixture obtained by oxidizing m-DIPB with air in the presence of a base, and m-D)-IP
The oxidation product containing is decomposed using an acid catalyst in the presence of toluene as a water-insoluble solvent to obtain resorcin, and after removing the catalyst, the entire amount of acetone, water, and toluene is distilled off under reduced pressure. Acetone can leftovers. Add water, toluene, and
Rani m-isopropylphenol (Examples 1 to 7),
Or, after adding m-isopropenylphenol (Example 8), dioxane (Example 9), MIBK (Example 10), or acetonitrile (Example 11), the deacetonization can residue is separated into oil and water, ) The extracted oil phase and aqueous phase were each analyzed.

The results are shown in Table 1.

From Table 1, when m-isopropylphenol, toisopropenylphenol, dioxane, MIBK, or acetonitrile is added, a large amount of resorcinol is distributed to the aqueous phase, and at the same time, the impurity 4-(3-hydroxycumyl)phenol ( It can be seen that CP-R3) is largely distributed to the oil phase side.

The aqueous phase obtained in Example 1 was roughly extracted twice with a solvent mixed with toluene and m-isopropylphenol at a ratio of 100:15.5, and after dehydration, the resorcinol was purified by distillation, and the purity was 99. 1q of .5% resorcinol was obtained with a recovery rate of 96%.

Comparative Examples 1 to 2 Water, toluene, and acetone were added to the deacetonization can residue obtained by the same method as in the example in the proportions shown in Table 1, and then the deacetonization can residue was separated into oil and water. The obtained oil phase and aqueous phase were each analyzed.

The results are also shown in Table 1.

In the case of Comparative Example 1 in which only water and toluene were added, CP-
A tar phase containing a large amount of R3 appeared. In general, it can be seen from Table 1 that although the partition coefficient of resorcinol to the aqueous phase side is very high, a large amount of CP-R5, an impurity, also migrated to the aqueous phase side.

When acetone is further added to water and toluene (Comparative Example 2)
) is not practical because it forms an emulsion and the oil-water compatibility deteriorates.

After dehydrating the aqueous phase in Comparative Example 1, resorcin was purified by distillation, and resorcin with a purity of 98.5% was obtained with a recovery rate of 93.
Obtained in %.

Water, toluene, and isopropylphenol, or isopropenylphenol, or dioxane, or MIBK or acetonitrile in the amounts shown in Table 1 were added to the deacetonization can residue obtained in the same manner as in the example. After that, the oil and water were separated.

In this case, as in Comparative Example 1, a tar phase appeared and was not practical.

Note that in the partition coefficients shown in Table 1, the larger the value of the partition coefficient of R3, the higher the proportion of R8 extracted into the aqueous phase. Therefore, it shows that the recovery rate of R3 increases, and the increase in the distribution coefficient of CP-R3 indicates that the impurity C
This indicates that P-R3 is less likely to be extracted into the aqueous phase, and therefore the purity of R3 recovered at this time is higher.

mini 11th day

[Brief explanation of the drawing]

FIG. 1 is a flowchart illustrating the resorcinol recovery method according to the present invention. Agent Patent Attorney Shunichi Suzuki

Claims (1)

[Claims] (1) The oxidation product containing m-diisopropylbenzene dihydroperoxide obtained by oxidizing m-diisopropylbenzene with molecular oxygen is acid-decomposed using an acid catalyst in the presence of an aromatic hydrocarbon solvent, and acetone is In the deacetonization can residue obtained by distillation, monohydric phenols,
At least one compound selected from the group consisting of nitriles, cyclic ether compounds, and water-insoluble dialkyl ketones is added in an amount of 5 parts by weight or more, and a sufficient amount of water to form two liquid phases. 1. A method for recovering resorcin, which comprises separating the residue of a deacetonization can into oil and water in the presence of a solvent, and recovering resorcin from the resulting aqueous phase.