ES2557052A2 - Method for producing carboxylic acid and ketone and / or alcohol - Google Patents

Abstract

In accordance with the present invention, there is provided a method of producing a ketone and / or alcohol in high yield. The method includes the steps of mixing an oxidation reaction solution, which is obtained by oxygenating a hydrocarbon compound with molecular oxygen, and water, and separating the oxidation reaction solution into an oily phase that includes a hydroperoxide and an aqueous phase that includes a carboxylic acid; concentrate the aqueous phase to obtain a concentrated solution that includes the carboxylic acid and recover water; removing the carboxylic acid from the water recovered in the concentration stage; recirculate the water, from which the carboxylic acid has been removed, to the separation stage; and decompose the hydroperoxide in the oil phase to give a ketone and / or an alcohol.

Description

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DESCRIPTION

Method for producing carboxylic acid and ketone and / or alcohol Field of the invention

The present invention relates to a method of producing a carboxylic acid and a ketone and / or an alcohol.

Background of the invention

The oxygenation of a hydrocarbon compound with molecular oxygen and the production of a corresponding ketone and / or alcohol have been widely known for years. Especially, cyclohexanone and / or cyclohexanol produced by the oxidation of cyclohexane are significantly important compounds as starting materials of nylon 6 and nylon 6,6.

The oxidation of a hydrocarbon compound with molecular oxygen takes place through a corresponding hydroperoxide. Generally, a hydrocarbon compound is oxidized to give a hydroperoxide with high selectivity. However, since various by-products are formed in the process of decomposing a hydroperoxide, the selectivity decreases. In order to avoid the decrease in selectivity, a method is generally used in which an oxidation reaction stops at a low conversion rate phase, the oxidation reaction solution is sent to the next stage maintaining a state in the one that a hydroperoxide remains without decomposition and the hydroperoxide decomposes with high selectivity.

However, although the oxidation reaction stops at the stage of a low conversion rate, it is inevitable that by-products are formed. By-products, for example, various hydrocarbon compounds, alcohols, ketones, peroxides, aldehydes, esters and carboxylic acids, various types of condensates, carbon monoxide and carbon dioxide which are all different from a starting material or an object are mentioned. Among these by-products, carboxylic acids and esters are produced especially with a high rate.

Some carboxylic acids in these by-products are useful compounds that have a

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industrially valuable value. For example, an adipic acid obtained as a byproduct in the cyclohexane oxidation process is useful as a starting material for nylon 6,6. In addition, the 1,6-hexanediol obtained by hydrogenating an adipic acid is useful as a starting material for polyester and polyurethane. The separation of these useful and similar carboxylic acids from the oxidation reaction solution and the production of another useful object makes efficient use of the by-products.

In general lines there are two methods to separate and obtain carboxylic acids from an oxidation reaction solution. One of them is a method in which the oxidation reaction solution is neutralized by an aqueous solution of alkali and carboxylate salts are extracted to the aqueous phase. The other method is that a carboxylic acid is extracted with water (hereinafter referred to as "water extraction step") and the carboxylic acid is obtained as is. The former has a high extraction rate, however, there is a need to perform an additional extraction separation to isolate carboxylic acids by adding a stronger acid than a carboxylic acid, such as a mineral acid. For this reason, the first method has complex stages and a low rate of return. In addition, the first method needs an auxiliary material, such as a mineral acid. Therefore, at the industrial level the last method is generally used.

In the last method, an aqueous solution that includes carboxylic acids is concentrated and dehydrated and then esterified with alcohols. Then, a valuable diol such as 1,6-hexanediol is obtained after hydrogenation and purification by distillation. The alcohols formed in the hydrogenation process can be recirculated to the esterification stage.

In addition, the water recovered in the concentration and dehydration stage can be recirculated to the water extraction stage (hereinafter, the water recovered and to be recirculated is called "circulation water"). The purpose of the recirculation is to use water efficiently and recover selected target products such as cyclohexanone and / or cyclohexanol that dissolve in the aqueous phase in the water extraction stage.

[List of references]

[Patent Bibliography]

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[Patent document 1] Japanese Patent Application Publication No. 2011-512339 (PCT translation).

[Patent document 2] Japanese Patent Application Publication No. 2012-512876 (PCT translation).

Summary of the invention

Technical problem

The purpose of the present invention is to provide a method for producing a ketone and / or an alcohol in high yield.

Solution to the problem

According to one aspect of the present invention, a method of producing a carboxylic acid and a ketone and / or an alcohol is provided. The method includes the steps of mixing an oxidation reaction solution, which is obtained by oxygenating a hydrocarbon compound with molecular oxygen, and water, and separating the oxidation reaction solution into an oil phase that includes a hydroperoxide and an aqueous phase that includes a carboxylic acid; concentrate the aqueous phase to obtain a concentrated solution that includes carboxylic acid and recover water; remove the carboxylic acid from the water recovered in the concentration stage; recirculating the water, from which the carboxylic acid has been removed, to the separation stage; and decompose the hydroperoxide in the oil phase to give a ketone and / or an alcohol.

Advantageous effects of the invention

With the present invention it may be possible to produce a ketone and / or an alcohol with high yield.

Description of the realizations

In general, a hydroperoxide decomposes with an acid or an alkali. As for the hydroperoxides obtained from aliphatic hydrocarbons or alidclic hydrocarbons among the hydroperoxides, the corresponding ketone and / or alcohol can be obtained with a

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relatively high selectivity in decomposition with an alkali. However, in the decomposition with an acid, the selectivity is low. As described above, since hydroperoxides decompose in the acid condition in the extraction stage with water, the decomposition selectivity is low. Therefore, it is important to avoid as much as possible the decomposition of hydroperoxides in the water extraction stage.

The rate of decomposition of hydroperoxides in the acid condition depends on the concentration of hydrogen ions in the aqueous phase. The circulation water must be recirculated to the extraction stage with water. The carboxylic acids have a boiling point similar to that of water, and the carboxylic acids are concentrated by azeotropic distillation with water. Therefore, the circulation water shows a strong acidity. Therefore, by neutralizing these acids and reducing the concentration of hydrogen ions (ie, increasing the pH), it is assumed that the decomposition of hydroperoxides is avoided.

However, as a result of fine examinations by the inventors of the present invention, it was found that the decomposition of hydroperoxides was not avoided by neutralizing carboxylic acids in the circulating water. In fact, decomposition was rather accelerated by neutralization.

That is, the inventors found that it was necessary to remove not only the hydrogen ion but also the carboxylate anion in order to prevent the decomposition of hydroperoxides in the water extraction stage. Thus, the inventors came to complete the present invention.

The embodiments of the present invention are described in detail below.

There is no specific limitation on the structure of a hydrocarbon compound used in the present invention. As the hydrocarbon compound used in the present invention there are, for example, saturated chain hydrocarbons, unsaturated chain hydrocarbons, cyclic saturated chain hydrocarbons and cyclic unsaturated hydrocarbons.

As saturated chain hydrocarbons, saturated chain hydrocarbons having a number of carbon atoms of 3-10 are preferred. Specifically, as saturated chain hydrocarbons having a number of carbon atoms of 3-10,

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They cite propane, butane, pentane, hexane, heptane, octane, nonano, decane and the like.

As unsaturated chain hydrocarbons, unsaturated chain hydrocarbons having a number of carbon atoms of 3-6 are preferred. Specifically, propylene, butylene, pentene, hexene and the like are mentioned as unsaturated chain hydrocarbons having a number of carbon atoms of 3-6.

As cyclic saturated hydrocarbons, cyclic saturated hydrocarbons having a number of carbon atoms of 5-12 are preferred. Specifically, as cyclic saturated hydrocarbons having a number of carbon atoms of 5-12, cyclopentane, cyclohexane, cycloheptane, cyclooctane, cyclodecane, cycloundecane, cyclododecane and the like are mentioned.

As cyclic unsaturated hydrocarbons, cyclic unsaturated hydrocarbons having a number of carbon atoms of 5-12 are preferred. Specifically, as cyclic unsaturated hydrocarbons having a number of carbon atoms of 5-12, aliphatic cyclic unsaturated hydrocarbons are mentioned which have or do not have a side chain such as cyclopentene, cyclohexene, cyclooctene, cycloundecene, cyclododecene, cyclohexadiene, cyclooctadiene, cyclododecadiene cyclododecatriene and the like; and aromatic hydrocarbons having a side chain such as toluene, xylene and the like.

These examples of hydrocarbon compounds include their structural isomers. In addition, these hydrocarbon compounds may have a substituent group. As the substituent group there is mentioned an alkyl group, an aryl group, a carbonyl group, a carboxyl group, an amino group, a nitro group, a cyano group, an alkoxy group, a halogen atom and the like. By the way, it is preferable that the total number of carbon atoms of a substituted hydrocarbon compound be within the ranges described above.

As industrially important hydrocarbon compounds among these hydrocarbon compounds described above are cyclohexane, cyclododecane, toluene, xylene and the like.

The hydrocarbon compound used in the present invention is oxygenated with molecular oxygen and becomes at least one of an alcohol, a ketone and a hydroperoxide having the same number of carbon atoms as the original hydrocarbon compound. The

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alcohols and / or ketones are further oxygenated to produce carboxylic acids. Although the number of carbon atoms of carboxylic acids formed as by-products is the same as that of the original hydrocarbon compound in most cases, carboxylic acids having a number of carbon atoms smaller than the compound will be formed by decarboxylation and decarbonylation. original hydrocarbon.

For example, in the case where the hydrocarbon compound is cyclohexane, the alcohol is cyclohexanol, the ketone is cyclohexanone and the hydroperoxide is cyclohexyl hydroperoxide. In that case, formic acid, acetic acid, propionic acid, butrnic acid, valeric acid, caproic acid, sucdnic acid, glutaric acid, adipic acid, 1-oxicaproic acid and the like are formed as by-products.

Oxygenation of the hydrocarbon compound with molecular oxygen can be carried out using or not using a transition metal, such as cobalt, as a catalyst. Although the temperature in an oxidation reaction varies depending on the binding energy of a carbon-hydrogen bond of the hydrocarbon compound or whether a catalyst is present or not, oxygenation is generally carried out at 100-180 ° C, and more generally, at 120-170 ° C. In the case where the temperature is too low, there is a possibility of reducing productivity due to reasons such as that an oxidation reaction does not advance at an appropriate speed and that a large-scale reactor is necessary for an oxidation reaction. In the case where the reaction temperature is too high, there is a possibility of reducing the selectivity of a desired product. Generally, an oxidation step is carried out at a pressure that is 0.01-1 MPa greater than the vapor pressure of the hydrocarbon compound.

The water extraction stage is a stage in which an oxidation reaction solution and circulation water are mixed, and aqueous by-products such as carboxylic acids are extracted to the aqueous phase, thereby separating both phases. As long as the ratio of circulating water with respect to oxidation reaction solution is sufficient to extract aqueous by-products such as carboxylic acids to the aqueous phase, there is no specific limitation on the reason. However, it is preferable that the ratio of circulating water with respect to oxidation reaction solution is from equal to or greater than 0.1% by volume to equal to or less than 50% by volume. It is more preferable that the ratio is from equal to or greater than 1% by volume to equal to or less than 30% by volume. In the case where the water ratio

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of circulation is too low, there is a possibility that aqueous by-products, such as carboxylic acids, cannot be sufficiently extracted to the aqueous phase. In the case where the ratio of circulation water is too high, there is a possibility that a large amount of energy is needed to recover the circulation water.

The temperature in the extraction stage with water may be the same as or different from the temperature in the oxidation stage. In the latter case, it is possible to reduce the temperature in the extraction stage with water by cooling the oxidation reaction solution for the purpose, for example, of increasing the extraction capacity and preventing the decomposition of hydroperoxides. The temperature in the water extraction stage is generally 100 ° C-170 ° C and more preferably 120-165 ° C is adopted. In the case where the temperature is too high, there is a possibility that the hydroperoxides decompose in the extraction stage with water. In the case where the temperature is too low, there is a possibility that hydroperoxides remain in a discharge solution in a stage to decompose hydroperoxides or that the hydrolysis of esters in a stage to decompose esters does not advance sufficiently. By the way, it is possible to heat a discharge solution in the extraction stage with water in order to avoid the problems described above; however, there is the possibility of reducing the definitive selectivity of an alcohol and / or a ketone by inducing thermal decomposition of hydroperoxides.

There is no specific limitation on an apparatus for water extraction. In water extraction, water extraction and a liquid separation operation can be carried out within an apparatus using an extraction column such as a perforated plate extraction column, a rotating disc extraction column, a column of extraction of pulsed sieve plates and a column of extraction of vibrating plates. It is also possible to use an apparatus in which an extraction part is separated with extraction water and a liquid separation part. In the latter case, a mixing tank with agitation, a static mixer and the like can be used for the water extraction part. For the liquid separation part, for example, a decanter, a centrifugal separator, a cyclone for liquids and the like can be used. Among these devices, the combination of a static mixer and a decanter is the simplest and most practical. In addition, it is possible to put a part to promote the separation of liquid, such as a binder and the like, within the decanter. Although the temperature in the liquid separation stage may be different from the temperature in the water extraction stage, in general these temperatures are

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same.

The retention times for the extraction stage with water and the separation stage of Kquido vary depending on each device; however, it is preferable that the retention time including the two stages is from equal to or greater than 1 minute to equal or less than 60 minutes, and more preferably is from equal to or greater than 1 minute to equal or less than 30 minutes . In the case where the retention time is too short, there is a possibility that the separation between the oil phase and the aqueous phase is insufficient. In the case where the retention time is too long, a large-scale apparatus is necessary.

In the water extraction stage, a dicarboxylic acid, an oxycarboxylic acid and a monocarboxylic acid having a short carbon chain are mainly extracted. For example, in the case where the hydrocarbon compound is cyclohexane, formic acid, acetic acid, propionic acid, suctinic acid, glutaric acid, adipic acid, 1-oxicaproic acid and the like are extracted. The oil phase that is discharged by the water extraction stage and the liquid separation stage is sent to the next stage, that is, the hydroperoxide decomposition stage.

It is possible to use a transition metal catalyst such as vanadium, molybdenum, chromium, ruthenium, cobalt and the like to decompose hydroperoxides. However, a decomposition method in which an aqueous alkali solution is contacted with hydroperoxides can be simplified to be a single stage together with an optional next stage, that is, an ester decomposition stage (hereinafter document, the hydroperoxide decomposition stage together with the ester decomposition stage is called the "saponification stage").

As the alkali used in the saponification stage, an aqueous solution of alkali metal hydroxide such as sodium hydroxide and potassium hydroxide and the like, an aqueous solution of alkaline earth metal hydroxide such as magnesium hydroxide, calcium hydroxide and the like are preferably used. , and an aqueous solution of alkali metal carbonate such as sodium carbonate, potassium carbonate and the like. It is possible to use an alkali only and it is also possible to use mixed alkalis.

As long as the amount of an alkali is above the equivalent of the total amount of carboxylic acids and esters that are discharged through the separation stage of

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fluid, there is no specific limitation on the amount of an alkali. However, it is preferable that the amount of an alkali is 1.05 times the equivalent of the total amount of carboxylic acids and esters or more than 10 times the equivalent of that or less. It is more preferable that it is 1.15 times the equivalent to the total amount of carboxylic acids and esters at 3 times the equivalent thereto. In the case where the amount of an alkali is too small, there is a possibility that esters remain and the yield of the ketone and / or alcohol decreases. In the case where the amount of an alkali is too large, the alkali is wasted.

Generally, a particular heating or cooling device is not provided between the fluid separation stage, and the hydroperoxide decomposition stage and the ester decomposition stage. Therefore, it is possible to carry out each stage of water extraction, fluid separation, hydroperoxide decomposition and ester decomposition at the same temperature. Furthermore, due to the heat of decomposition of hydroperoxide, it is possible to carry out the hydroperoxide decomposition stage and the ester decomposition stage at a temperature slightly higher than the temperature in the water extraction stage and the fluid separation stage . In the latter case, the hydroperoxide decomposition stage and the ester decomposition stage are generally carried out at a temperature of 5 ° C-30 ° C higher than the water extraction stage and the separation stage of fluid

By the way, as described above, the hydroperoxide decomposition stage and the ester decomposition stage can be carried out as a single stage or different stages. In the latter case, hydroperoxides can be decomposed using a catalyst.

On the other hand, the aqueous phase, which is discharged by the water extraction stage and the fluid separation stage, is concentrated in a concentration stage, and separated to give a concentrated solution that includes carboxylic acids and water. That is, valuable carboxylic acids can be obtained through this stage. The temperature and concentration pressure at this stage are not specifically limited as long as the water evaporates under these conditions. Generally, this stage is carried out at normal pressure at a temperature of from 100 ° C or greater than equal to or less than 130 ° C.

The concentrated solution of carboxylic acids, which has been concentrated in the stage of

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concentration, includes a valuable carboxylic acid. Said carboxylic acid is optionally sent to a reaction stage and a purification stage, and another valuable compound is produced. For example, from a concentrated solution of carboxylic acids that include adipic acid and oxicaproic acid that have been produced in the oxidation in cyclohexane air, 1,6-hexanediol is produced through an esterification reaction and a hydrogenation reaction .

The circulation water recovered in the concentration stage is recirculated to the water extraction stage, which has already been mentioned. The circulating water includes carboxylic acids that have a boiling point close to that of water and can be an azeotrope with water. For example, the circulating water may include formic acid, acetic acid, propionic acid and the like. The decomposition of hydroperoxides is accelerated by an acid. As described above, in the decomposition of hydroperoxides by an acid, the selectivity of the desired ketone and / or alcohol is less than the selectivity in decomposition by an alkali or a catalyst. For this reason, the acid in the circulating water must be neutralized. Additionally, as described above, the inventors of the present invention found that in the case where the acid is an organic acid, since not only a hydrogen ion but also the organic acid itself promotes the decomposition of hydroperoxides, not only The hydrogen ion but also the organic acid itself must be removed from the circulation water. That is, the inventors found that removing carboxylic acids from the circulating water greatly contributes to the high yield of the desired ketone and / or alcohol.

By the way, within the scope of the present specification and the scope of the claims, "withdrawal" of carboxylic acid means that the concentration of carboxylic acids in the aforementioned water is reduced to be equal to or less than 50 mmol / l.

There is no specific limitation on a method of removal of carboxylic acids from the circulating water. A distillation purification method, which is the simplest and most practical, is available; however, there is a possibility that formic acid, acetic acid and the like may be azeotropic with water. In the withdrawal stage described above, it is possible to use a method in which water is purified by distillation after neutralizing carboxylic acids by means of an alkali. It is also possible to use a method in which water is purified using a separation membrane. The industrially simpler and more practical method is a method in which water is purified using a resin of

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ion exchange

As an ion exchange resin, an anion exchange resin is generally used. It is preferable to use a weak basic anion exchange resin if its easy recycling is considered. As a weak basic anion exchange resin, for example, it is possible to use a weak basic anion exchange resin having polyamine or dimethylamine as the exchange group. By the way, the operating temperature by the ion exchange resin is subject to restriction depending on the heat resistance of the ion exchange resin. In the case where a weak basic anion exchange resin is used, it is generally used at a temperature that is equal to or less than 100 ° C. In the case where a strong basic anion exchange resin is used, it is used at a temperature that is equal to or less than 60 ° C.

Examples

The present invention is described in detail below by examples; however, the present invention is not limited to the examples below.

<Effect of removing carboxylic acid on the decomposition of hydroperoxide in the extraction stage with water>

[Example 1]

An aqueous solution (pH 2.2) of 1% by weight formic acid was prepared. The aqueous solution was passed through a column filled with a weak basic ion exchange resin (DIAION WA20 manufactured by Mitsubishi Chemical Corporation) at 60 ° C, at a surface velocity of 1.5 (1 / h) in order of removing formic acid. As a result of the analysis of the column effluent with liquid chromatography, it turned out that formic acid was not detected and that the pH was 6.6.

211 g of the ion exchange processing water and 383 g of cyclohexane were added to a 1 l autoclave. After heating the autoclave at 160 ° C, 36.2 g of a cyclohexane solution containing 10% by weight of cyclohexyl hydroperoxide was introduced under pressure (forced feed) and reacted for one hour. As a result of the analysis of the reaction solution by gas chromatography, it turned out that the decomposition rate of cyclohexyl hydroperoxide was 54.4%,

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cyclohexanone selectivity was 24.1% and cyclohexanol selectivity was 41.5%.

[Comparison 1]

The decomposition of hydroperoxides was carried out in the same manner as in Example 1 except that treatment with ion exchange resin was omitted. The decomposition rate of cyclohexyl hydroperoxide was 99.8%, the selectivity of cyclohexanone was 22.0% and the selectivity of cyclohexanol was 38.0%.

[Comparison 2]

Hydroperoxide decomposition was carried out in the same manner as in comparison 1 except that an aqueous solution of formic acid was prepared to have pH 7.2 neutralized with sodium hydroxide. The cyclohexyl hydroperoxide decomposition rate was 100%, the cyclohexanone selectivity was 20.8% and the cyclohexanol selectivity was 35.8%.

<Effect of the removal of carboxylic acid in the circulation water>

[Example 2]

250 g of cyclohexane and 293 mg of a solution of cyclohexane containing 0.1% by weight of cobalt octylate (0.2 ppm by weight of Co metal) were added to a 500 ml autoclave made of SUS316L. While nitrogen was introduced through a gas blowing nozzle, the internal temperature was raised to 157 ° C. Once the internal temperature reached 157 ° C, the blow gas was changed by air. While blowing air at a rate of 1 l / min, the cyclohexane oxidation reaction was carried out for 21 minutes. A discontinuous reaction of this type was carried out 10 times and an oxidation reaction solution was obtained. The conversion rate of cyclohexane in the oxidation reaction was 4.2%. The cyclohexanone selectivity was 19.4%, the cyclohexanol selectivity was 41.6%, the cyclohexyl peroxide selectivity was 16.3%, the adipic acid selectivity was 1.7% and the selectivity of Oxicaproic acid was 3.1%.

After adding 350 g of water to the oxidation reaction solution and stir the solution of

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oxidation reaction, the separation of liquid was carried out and the extraction water was obtained. The extraction water was distilled by simple distillation at a tail temperature of 100 ° C to 120 ° C. The extraction water was concentrated until the water in the distillation still reached 3% by weight and circulation water was obtained. As a result of the analysis of the circulating water with liquid chromatography, it turned out that 1.02% by weight of formic acid, 0.33% by weight of acetic acid, 0.04% by weight of propionic acid were contained, 0.03% by weight of butrnco acid, and the pH was 2.17. Circulation water was treated using an ion exchange resin in the same manner as in Example 1. The result was that in the ion exchange processing water no formic acid, acetic acid, propionic acid or butric acid were detected, and Its pH was 6.59.

Meanwhile, the oxidation reaction solution was concentrated 10 times and a concentrated oxidation reaction solution was obtained. The concentrated oxidation reaction solution included 12.52% by weight of cyclohexanone, 27.40% by weight of cyclohexanol and 12.45% by weight of cyclohexyl hydroperoxide. 440 g of cyclohexane and 70 g of the ion exchange processing water were added to a 1 l autoclave. After heating the autoclave at 160 ° C, 45 g of the concentrated oxidation reaction solution was forcedly fed and reacted for 5 minutes with stirring. Then the liquid separation was carried out. The separated oil phase was concentrated 10 times and similar reaction operations were repeated using new ion exchange water. After repeating the reaction liquid separation operations three times in total, the oil phase and the aqueous phase were analyzed by gas chromatography. The result was that the decomposition rate of cyclohexyl hydroperoxide was 37.6%, the selectivity of cyclohexanone was 24.7% and the selectivity of cyclohexanol was 42.5%. On the other hand, as a result of carrying out a quantitative analysis of adipic acid and oxicaproic acid in the aqueous phase by liquid chromatography, the adipic acid extraction rate was 82.5% and the oxicaproic acid extraction rate was of 81.9%.

The separated oil phase was concentrated again 10 times. 400 g of cyclohexane and 80 g of a 17% by weight aqueous solution of sodium carbonate were mixed and heated to 160 ° C. The concentrated oil phase was forced into the heated mixed solution and stirred for 60 minutes at 160 ° C. In doing so, the decomposition of the remaining cyclohexyl hydroperoxide and the hydrolysis of esters (the saponification treatment) were carried out at the same time. After the liquid separation, it

analyzed the oil phase and the aqueous phase by gas chromatography. The decomposition rate of cyclohexyl hydroperoxide was 100%, the selectivity of

cyclohexanone was 44.4% and the selectivity of cyclohexanol was 34.3%, which was

both based on cyclohexyl hydroperoxide on the oxidation reaction solution.

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[Comparison 3]

An experimental operation was carried out in the same manner as in Example 2 except that the ion exchange resin treatment was omitted. The rate of decomposition of cyclohexyl hydroperoxide after the extraction treatment with water was 60.3%, the selectivity of cyclohexanone was 22.5% and the selectivity of

Cyclohexanol was 39.3%. The adipic acid extraction rate was 81.9% and the rate

Extraction of oxicaproic acid was 80.5%. In addition, the decomposition rate of cyclohexyl hydroperoxide after the saponification treatment was 100%, the cyclohexanone selectivity was 37.9% and the cyclohexanol selectivity was 35.3%, which were both based on hydroperoxide of cyclohexyl in the oxidation reaction solution.

Table 1 below shows the results described above. As shown in Table 1, apparently, by removing the carboxylic acids from the circulation water, a desired ketone and / or alcohol were obtained at high yield.

[Table 1]

 Water phase treatment Water extraction condition Water extraction Water extraction and saponification treatment

 Aqueous phase

 Treatment method Temperature (° C) Surface speed (i / h) __________eH__________ Oil phase Water phase Temperature (° C) Treatment time (min) CHP decomposition rate to Selectivity (%) Decomposition rate - CHP to Selectivity (%)

 Before treatment

 After treatment ON OL ON + OL ON OL ON + OL

 Example 1

 Aqueous solution of formic acid at 1% by weight Treatment with IR (WA20) 60 1.5 2.2 6.6 CHP / Cx Solution of formic acid treated with IR 160 60 54.4 24.1 41.5 65, 6 - - - -

 Comparison 1

 Aqueous solution of formic acid at 1% by weight None - - 2,2 - CHP / Cx Solution of formic acid 160 60 99.8 22.0 38.0 60.0 - - - -

 Comparison 2

 Aqueous solution of formic acid at 1% by weight Neutralization with NaOH Ambient temperature 2.2 7.2 CHP / Cx Solution of neutralized formic acid 160 60 100 20.8 35.8 56.6 - - - -

 Example 2

 Circulation water IR treatment (WA20) 60 1.5 2.17 6.59 Oxidation reaction solution Circulation water treated with IR 160 5 min * 3 times 37.6 24.7 42.5 67.2 100, 0 44.4 34.3 78.7

 Comparison 3

 Circulation water None - - 2.17 - Oxidation reaction solution Circulation water 160 5 min * 3 times 60.3 22.5 39.3 61.8 100.0 37.9 35.3 73.3

Claims (1)

5 10 fifteen twenty 25 Method for producing a carboxylic acid and a ketone and / or an alcohol, the method comprising the steps of: mixing an oxidation reaction solution, which is obtained by oxygenating a hydrocarbon compound with molecular oxygen, and water, and separating the oxidation reaction solution into an oil phase that includes a hydroperoxide and an aqueous phase that includes a carboxylic acid; concentrate the aqueous phase to obtain a concentrated solution that includes carboxylic acid and recover water; remove the carboxylic acid from the water recovered in the concentration stage; recirculating the water, from which the carboxylic acid has been removed, to the separation stage; Y decompose the hydroperoxide in the oil phase to give a ketone and / or an alcohol. Method according to claim 1, wherein the removal of the carboxylic acid is carried out using an ion exchange resin. Method according to claim 2, wherein the ion exchange resin is an anion exchange resin. Method according to any one of claims 1 to 3, wherein the hydroperoxide is cyclohexyl hydroperoxide, the ketone is cyclohexanone and the alcohol is cyclohexanol.