WO2002072516A1

WO2002072516A1 - Method for producing bisphenol a

Info

Publication number: WO2002072516A1
Application number: PCT/JP2002/001924
Authority: WO
Inventors: Tetsuya Saruwatari; Naoya Kawano
Original assignee: Idemitsu Petrochemical Co., Ltd.
Priority date: 2001-03-08
Filing date: 2002-03-01
Publication date: 2002-09-19
Also published as: TWI310376B; JP2002265403A

Abstract

A method for producing bisphenol A through condensing phenol and acetone using a sulfonic acid based ion exchange resin as a catalyst and a mercaptan as an auxiliary catalyst, characterized in that use is made of a sulfonic acid based ion exchange having a washability such that, when it is washed with ion-exchanged water in a volume 5 to 20 times its volume swollen with water and then is agitated in a phenol in a volume 1 to 3 times its volume swollen with water at a temperature of 50 to 80°C for 2 to 5 hr, the phenol after solid-liquid separation has a sulfur content of 1 ppm by weight or less. The method can be used for producing bisphenol A advantageously from an economical view point, since the above washing method is easy and simple to operate and a sulfonic acid based ion exchange resin which does not need a long time can be easily selected using the above washing method.

Description

Description Bisfuynol A Production Method Technical Field

The present invention relates to a method for producing bisphenol A, and more specifically, to produce bisphenol A [2,2-bis (4-hydroxyphenyl) propane] from phenol and acetone using a sulfonic acid type ion exchange resin catalyst. In this regard, the present invention relates to a method for producing bisphenol A, wherein a catalyst requiring a short time for washing is selected and used by a specific simple washing method as the catalyst. Background art

Bisphenol A is known to be an important compound as a raw material for engineering plastics such as polycarbonate resin and polyarylate resin, or epoxy resin, and the demand for bisphenol A has been increasing in recent years.

This bisphenol A is produced by condensing excess phenol and acetone in the presence of an acidic catalyst and optionally a cocatalyst such as a sulfur compound.

Conventionally, inorganic acid such as sulfuric acid or hydrogen chloride has been used as an acid catalyst in this reaction. In recent years, cation exchange resins have attracted attention (British Patent No. 8422209, Nos. 8495655 and 883391) have come to be used industrially.

On the other hand, as a sulfur compound used as a cocatalyst, it is known that alkyl mercaptans having or not having a substituent such as methyl mercaptan, ethyl mercaptan, and thiodaricholic acid are effective (US Patent No. No. 2,359,242 and No. 2,775,620). These mercaptans have the effect of increasing the reaction rate and the selectivity. For example, in the production of bisphenol A, 2- (2-hydroxyphenyl) 1-2-(. 4-hydroxyphenyl) propane (o, p'-isomer) is mainly produced as a by-product of the reaction. In addition, trisphenol and polyphenol are produced. In particular, when used as a raw material for a polycarbonate resin or a polyarylate resin, bisphenol A of high purity with little content of these by-products and no coloring is required. For this reason, mercaptans are used as a co-catalyst to increase the reaction rate, suppress the generation of the by-products, and increase the selectivity.

When bisphenol A is produced industrially by condensing phenol and acetone, generally, phenol and acetone as raw materials and mercaptans as a cocatalyst are continuously supplied to a reaction tower filled with the cation exchange resin. A fixed bed continuous reaction system is adopted.

In this fixed bed continuous reaction system, a fixed bed multistage reaction apparatus in which two or more reaction groups filled with the cation exchange resin are connected in series is usually used. As the cation exchange resin, a strongly acidic sulfonic acid type ion exchange resin is frequently used from the viewpoint of catalytic activity and the like.

However, when this sulfonic acid type ion exchange resin is used as a catalyst, sulfonic acid is eliminated from the ion exchange resin after the reaction starts, and the sulfonic acid eluted in the reaction solution is exposed to a high temperature in a later step. Is known to cause the decomposition of bisphenol A and produce colored by-products. These colored impurities may cause undesirable situations such as deterioration of the hue of bisphenol A product, and particularly in bisphenol A for polycarbonate resin used as a material for optical members such as optical discs and optical fibers. Therefore, there is a demand for a colorant having as little color impurities as possible and having a good hue without coloring.

Therefore, as a pretreatment of the sulfonic acid type ion exchange resin, various cleaning methods have been tried so far. For example, a method in which the catalyst is washed with deionized water until the specific conductivity of the washing solution becomes less than about 50 μΩ- ¹ cm at 25 ° C., and then the washed ion-exchange resin is subjected to a dehydration treatment (Japanese Unexamined Patent Application Publication No. A method of washing an acidic cation exchange resin with water and then with a phenol (Japanese Patent Application Laid-Open No. Hei 9-16969) discloses a method of washing a sulfonic acid type ion exchange resin. After filling in the reactor, the sulfonic acid-type ion-exchange resin is washed with water until the washing wastewater has a pH of 6 or more, and then the phenol is washed, and the sulfonic acid concentration in the washed phenol is 2 ppm by weight or less. How to do until (Japanese Unexamined Patent Publication No. 2000-144365).

As described above, in the case of an acid-type cation exchange resin, it is known that water washing and phenol washing are effective, and by carrying out this washing sufficiently, the hue of the product after catalyst filling or exchange is maintained well. It is also known that this can be done. However, at present, after the catalyst is filled in the reactor, water cleaning and phenol cleaning take a very long time, resulting in a situation in which economic efficiency is significantly impaired. For example, in the case of a sulfonic acid type ion exchange resin that has been stored in the air for a long time in a wet state, a colored eluate composed of polystyrenesulfonic acid is generated on the surface and inside the pores, and it takes a long time to wash.

Therefore, before filling the flow-through reactor with the sulfonic acid-type ion exchange resin, it is necessary to easily determine the washing performance of the resin, that is, how much time is required for water washing and phenol washing. It has been. Disclosure of the invention

In the present invention, in such a situation, when producing bisphenol A from phenol and acetone using a sulfonic acid type ion exchange resin catalyst, the time required for washing is reduced by an easy washing method as the catalyst. An object of the present invention is to provide a method for producing bisphenol A using a sulfonic acid type ion exchange resin by selecting it. Other objects of the present invention will become apparent from the following description of the specification.

The present inventors have conducted intensive studies to achieve the above object, and as a result, the sulfonic acid type ion exchange resin was subjected to a cleaning treatment by a specific simple cleaning method using ion exchange water and phenol, and the final treatment was carried out. It has been found that the purpose can be achieved by using a sulfonic acid type ion exchange resin having a sulfur concentration of 1 ppm by weight or less in the washed phenol obtained as a catalyst. The present invention has been completed based on such findings.

That is, the present invention relates to the production of bisphenol A by condensing phenol and acetone using a sulfonic acid type ion exchange resin as a catalyst and mercaptans as a cocatalyst, Acid type After washing the ion-exchange resin with ion-exchanged water having a volume of 5 to 20 times the water swelling volume, the resin is washed in a phenol having a volume of 1 to 3 times the water swelling volume at a temperature of 50 to 80 at a temperature of 50 to 80. The present invention also provides a method for producing bisphenol A, characterized by using a washing phenol having a sulfur concentration of 1 ppm by weight or less after solid-liquid separation after washing with stirring for up to 5 hours. BEST MODE FOR CARRYING OUT THE INVENTION

The method of the present invention is a method for producing bisphenol A by condensing fuynol and acetone using a sulfonic acid type ion exchange resin as a catalyst and mercaptans as a cocatalyst, wherein the sulfonic acid type ion exchange resin is Is not particularly limited as long as it is a strongly acidic cation exchange resin having a sulfonic acid group. Examples thereof include a sulfonated styrene dibutyl benzene copolymer, a sulfonated crosslinked styrene polymer, a phenol formaldehyde sulfonic acid resin, and a benzene formaldehyde sulfonate. And a sulfonic acid resin. These may be used alone or in combination of two or more.

In the condensation of phenol and acetone in the present invention, generally, a fixed bed continuous reaction system in which phenol, acetone and mercaptans are continuously supplied and reacted in a reaction tower filled with the above-mentioned sulfonic acid type ion exchange resin. Is used. At this time, the number of reactors may be one, or two or more reactors may be arranged in series or in parallel, but industrially, two or more reactors filled with sulfonic acid type ion exchange resin are connected in series. However, it is particularly advantageous to employ a fixed-bed multistage continuous reaction system.

When the sulfonic acid-type ion-exchange resin is used as a catalyst, sulfonic acid is desorbed from the ion-exchange resin after the reaction starts, as described in "Background Art", and the sulfonic acid eluted in the reaction solution is removed. However, when exposed to high temperatures in a later step, it causes the decomposition of bisphenol A and produces colored by-products. The mold ion-exchange resin is washed with water and then treated with phenol. When the sulfonic acid type ion exchange resin filled in such a reactor is washed with water and then with fininol, depending on the ion exchange resin, the above-mentioned washing treatment takes a long time, which is economically disadvantageous. It may be.

In the method of the present invention, in order to cope with such a situation, the water and then the sulfonic acid type ion exchange resin having a short washing treatment time with phenol are selected and used by a simple washing method described below. .

In this simple washing method of the present invention, the sulfonic acid type ion exchange resin is washed with ion exchange water having a volume of 5 to 20 times its water swelling volume, and then having a phenol having a volume of 1 to 3 times its water swelling volume. Washing with stirring at a temperature of 50 to 80 ° C for 2 to 5 hours, and selecting a sulfonic acid type ion exchange resin having a sulfur concentration of 1 ppm by weight or less in the washed phenol after solid-liquid separation.

Specifically, first, a sulfonic acid type ion exchange resin is placed in a container, and then ion exchange water having a volume about twice the water swelling volume of the ion exchange resin is added. After stirring, the mixture is left standing. Drain the supernatant to the interface of the ion exchange resin. This operation is repeated several times until the total volume of ion-exchanged water becomes 5 to 20 times the water swelling volume of the sulfonic acid type ion exchange resin. This washing treatment with ion-exchanged water is performed at room temperature, that is, at a temperature of about 10 to 30 ° C. At this time, if the total amount of ion-exchanged water used is less than 5 times the volume, the washing effect with water will be insufficient. become unable. In addition, a difference in the amount of eluted material during phenol washing between resins to be compared with a resin having a volume of more than 20 times the volume is less likely to appear.

After the completion of the washing treatment with ion-exchanged water in this way, after filtration under reduced pressure using a glass filter or the like, the water-washed sulfonic acid-type ion-exchange resin is returned to the recycle container. Next, phenol having a volume of 1 to 3 times the water swelling volume of the sulfonic acid type ion exchange resin is added, and the mixture is washed with stirring at a temperature of 50 to 80 ° C for 2 to 5 hours. Then, after standing, the sulfur concentration in the supernatant phenol is measured, and a sulfonate-type ion-exchange resin having a value of 1 ppm by weight or less is used as a catalyst.

At this time, if the amount of the phenol used is less than 1 volume, the resin is not sufficiently washed with the phenol, and resin fine particles may be taken in when collecting the supernatant. If the volume is more than 3 times the volume, the difference in the amount of eluted material when washing with phenol is unlikely to appear between the compared resins. Next, in the method of the present invention, a method for producing bisphenol A by condensing phenol and acetone with the sulfonic acid-type ion exchange resin as a catalyst and mercaptans as a co-catalyst will be described.

The mercaptans used in the present invention are compounds having an SH group in a free form in the molecule. Examples of such a compound include alkyl mercaptans, carboxyl groups, amino groups, and hydroxyl groups. Alkyl mercaptans having one or more groups, for example, mercaptocarboxylic acid, aminoalkanethiol, mercaptoalcohol and the like can be used. Examples of such mercaptans include methyl mercaptan, ethyl mercaptan, n-butynolemercaptan,

Thiocarboxylic acids such as mercaptopropionic acid; aminoaminothiols such as 2-aminoethanethiol and 2,2-dimethylthiazolidine; and mercapto alcohols such as mercaptoethanol. Among them, alkyl mercaptan is useful. Particularly preferred in terms of the effect as a catalyst. Further, these mercaptans may be used alone or in combination of two or more.

These mercaptans can be immobilized on the sulfonic acid-type ion exchange resin to function as a promoter.

The amount of the mercaptans class generally against acetone raw material, 0.1 to 2 0 mole ^_0/0, is selected preferably from 1 to 1 0 mol% of the range.

Although there is no particular limitation on the ratio of phenol and acetone used, it is desirable that the amount of unreacted acetone be as small as possible in view of the ease of purification and economical efficiency of the produced bisphenol A. It is advantageous to use the phenol in excess of the stoichiometric amount. Usually, 3 to 30 moles, preferably 5 to 15 moles, of phenol are used per mole of acetone. In the production of bisphenol A, the reaction solvent is generally not required, except that the reaction liquid is reacted at a low temperature at which the viscosity of the reaction liquid is too high or the solidification makes operation difficult.

In the present invention, phenol, acetone, and the mercaptans are continuously supplied to a reaction tower filled with a sulfonic acid-type ion exchange resin, which requires a short time for catalyst cleaning, which is selected by the above-described simple cleaning method. Fixed bed continuous reaction system You can. In the present invention, prior to the reaction, a washing treatment of the sulfonic acid type ion exchange resin filled in the reaction tower is performed. In this cleaning, first, water is flowed through a reaction tower filled with a sulfonic acid-type ion exchange resin, and the water is washed until the pH of the washing wastewater becomes about 5.5 to 7. Then, phenol is flown while maintaining the ion exchange resin temperature of the reaction tower at about 50 to 80 ° C., and water in the sulfonic acid type ion exchange resin is replaced with phenol, and phenol washing is performed in the washing phenol. Until the sulfur concentration in the mixture becomes 1 wt.

Next, phenol, acetone and mercaptans are continuously supplied to the reaction tower, and the reaction is carried out by a fixed bed continuous reaction system.

The reaction conditions in this fixed bed continuous reaction system will be described.

First, the acetone nophenol molar ratio is usually selected in the range of lZ30 to l / 3, preferably 1 to 15 to 1/5. If the molar ratio is less than 1/30, the reaction rate may be too slow. If the molar ratio is more than 1 Z3, impurities may be generated more and the selectivity of bisphenol A tends to decrease. On the other hand, when the mercaptans are not immobilized on the sulfonic acid type ion exchange resin, the mercaptans Zaceton • The molar ratio is usually selected from the range of 0.1 to 100 to 20100, preferably 1 to 100 to 100. It is. If the molar ratio is less than 0.1 / 100, the effect of improving the reaction rate and the selectivity of bisphenol A may not be sufficiently exhibited. There is not much improvement. The reaction temperature is selected in the range of usually 40 to 150 ° C, preferably 60 to 110 ° C. If the temperature is lower than 40 ° C, the reaction rate is low, the viscosity of the reaction solution is extremely high, and in some cases, there is a possibility of solidification. If the temperature exceeds 150 ° C, the reaction control becomes difficult, and bisphenol A The selectivity of (p, p'-isomer) decreases, and the sulfonic acid type ion exchange resin of the catalyst may decompose or deteriorate. Furthermore, the raw material mixture LHSV (liquid hourly space velocity) is generally 0. 2 to 30 h r- preferably 0.5 5: is selected in the range of L 0 hr ^1.

In the method of the present invention, the reaction mixture that has come out of the reaction tower is subjected to post-treatment by a known method, and bisphenol A is taken out. Next, an example of this post-treatment will be described. First, concentration is performed prior to crystallization. Especially regarding the concentration conditions Although there is no limitation, the concentration is usually performed at a temperature of 130 to 170 ° C and a pressure of 13 to 53 kPa. If the temperature is lower than 130 ° C, a high vacuum is required. If the temperature is higher than 170 ° C, impurities may increase or coloring may occur. The concentration of bisphenol A in the concentrated residue is 25 to 40% by weight. Advantageously it is in the range / ₀ . If the concentration is less than 25% by weight, the recovery of bisphenol A is low, and if it exceeds 40% by weight, it becomes difficult to transfer the slurry after crystallization.

Crystallization of the adduct of bisphenol A and phenol from the concentrated residue is usually carried out by vacuum cooling crystallization, which utilizes the latent heat of vaporization of water under reduced pressure. In this vacuum cooling crystallization method, about 3 to 20% by weight of water is added to the concentrated residue, and crystallization is performed at a normal temperature of 40 to 70 ° C and a pressure of 3 to 13 kPa. An analysis process is performed. If the amount of water added is less than 3% by weight, the heat removal ability is not sufficient, and if it exceeds 20% by weight, the dissolution loss of bisphenol A increases, which is not preferable. If the crystallization temperature is lower than 40 ° C, the viscosity of the crystallization liquid may increase or solidify. If the crystallization temperature exceeds 70 ° C, the dissolution loss of bisphenol A increases, which is not preferable.

Next, the adduct of bisphenol A and phenol thus crystallized is separated by a known method, and is usually subjected to a washing treatment with phenol. Next, the washed adduct is separated into bisphenol A and phenol, in which case the temperature is usually from 130 to 200 ° C, preferably from 150 to 180 ° C. The pressure is usually selected in the range of 3 to 20 kPa.

Bisphenol A obtained by this separation treatment is substantially completely removed of the residual phenol therein by a method such as steam stripping, so that high-quality bisphenol A can be obtained.

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

Example 1

(1) Simple cleaning test

After filling the sample bottle of 100 milliliter volume with the sulfonic acid type ion exchange resin in a water swelling volume of 50 milliliter, the ion exchange water was added until the total volume including the resin reached 100 milliliter. added. Then, after stirring, let it stand still, The supernatant was drained to the interface. After this operation was repeated 10 times, the solution was filtered under reduced pressure with an aspirator using a glass filter, and water was roughly removed.

This sulfonic acid type ion exchange resin was returned to the 100 milliliter sample bottle again, and phenol was added until the total volume including the resin reached 100 milliliter, followed by stirring at 70 ° C for 3 hours. After the stirring, the mixture was allowed to stand, and the supernatant was collected, and the sulfur concentration was measured. As a result, it was less than 1 wt p ρπα.

(2) Continuous distribution test

70 ml of the same sulfonic acid type ion exchange resin used in (1) above was filled in a stainless steel tube having an inner diameter of 14 mm and a length of 450 mm. Next, ion-exchanged water was continuously passed through the reactor at 10 milliliter Zh for 25 hours. The pH of the washing wastewater measured 25 hours later was 5.5, indicating that the litmus paper was neutral.

Next, the temperature of the resin layer was raised to 70 ° C., and phenol was flown at 10 ml / h for 25 hours to perform dehydration. After 25 hours, the water concentration in the ethanol was 0.3% by weight. At this time, the sulfur concentration in the phenol and the hue of the phenol were measured, and as a result, the sulfur concentration was 4 wt ppm and the hue was 30 or more in APHA.

Next, phenol washing was performed under the same conditions as the above-mentioned dehydration conditions. Ten hours after the start of the phenol washing, the sulfur concentration in the washed phenol dropped to 1 wt ppm. At this time, the hue of the washed phenol was 15 with APHA.

Comparative Example 1

(1) Simple cleaning test

The same sulfonic acid type ion exchange resin as that used in Example 1 was stored in the air for 2 months, and then the same operation as in Example 1 (1) was performed. The supernatant phenol was collected, and the sulfur concentration was measured. As a result, it was 4 wt ppm.

(2) Continuous distribution test

The same operation as in Example 1 (2) was performed using a sulfonic acid type ion exchange resin kept in the same air as that used in (1) above for 2 months.

When the pH of the washing wastewater after 25 hours of water washing was measured, the pH was 5. °, and the litmus test paper showed neutrality. In addition, phenol after 25 hours of dehydration with phenol The water concentration in the nozzle was 0.3% by weight. At this time, the sulfur concentration in the phenol and the hue of the phenol were measured, and as a result, the sulfur concentration was 8 ppm by weight, and the hue was 30 or more by APHA.

Next, fuñol washing was performed under the same conditions as the dehydration conditions described above. Forty hours after the start of the phenol washing, the sulfur concentration in the washed phenol dropped to 1 wt ppm. At this time, the hue of the washed phenol was 20 in APHA. As can be seen from Example 1 and Comparative Example 1, there was a correlation between the result of the simple cleaning test and the result of confirmation in the continuous flow system. Industrial applicability

According to the present invention, when bisphenol A is produced from fuunol and acetone using a sulfonic acid type ion exchange resin catalyst, the sulfonic acid type which requires a short time for cleaning by a specific simple cleaning method is used as the catalyst. By selecting and using an ion exchange resin, bisphenol A can be produced economically and advantageously.

Claims

The scope of the claims

(1) In producing bisphenol A by condensing phenol and acetone with a sulfonic acid type ion exchange resin as a catalyst and mercaptans as a cocatalyst, sulfonic acid is used as the sulfonic acid type ion exchange resin. The ion-exchange resin is washed with ion-exchanged water having a volume of 5 to 20 times the water swelling volume, and then washed at 50 to 80 ° C in phenol having a volume of 1 to 3 times the water swelling volume. A process for producing bisphenol A, comprising washing with stirring at a temperature for 2 to 5 hours and using a phenol having a sulfur concentration of 1 ppm by weight or less in the washed phenol after solid-liquid separation.

2. The process for producing bisphenol A according to claim 1, wherein the mercaptan as the co-catalyst is selected from the group consisting of alkyl mercaptans, thiocarbonic acid, aminoalkanethiol and mercapto alcohol.

3 The phenolic mercaptans are selected from the group consisting of methyl mercaptan, ethyl mercaptan, n-butyl mercaptan n-octyl mercaptan, and 0.1 to 20 mol% based on acetone. 3. The method for producing bisphenol A according to claim 2, wherein the bisphenol A is used in an amount of:

4.Production of bisphenol A according to claim 1, wherein the phenol and aceton are reacted under the condition that the molar ratio of acetone Z phenol is 1/30 to lZ3 and the reaction temperature is 40 to 150 ° C. Method. ·