JPH0245439A - Production of bisphenol - Google Patents

Abstract

PURPOSE:To carry out reaction of phenols with a ketone using a heteropolyacid having structure condensing an oxide of Mo, W, V, etc., with an oxyacid of P, Si, As, Ge, etc., in obtaining bisphenol from phenols and ketone. CONSTITUTION:Phenols are reacted with a ketone using a heteropolyacid of 0.05-0.5mol based on 1mol ketone as an acidic condensing agent to provide bisphenol. The above-mentioned heteropolyacid has a structure condensing at least one kind of oxide selected from Mo, W and V with an oxyacid selected from P, As, Si and Ge and atomic ratio of the former to the latter is 2.5-12 (e.g., tungstophosponic acid). According to the above-mentioned method, ketone conversion can be improved, because lowering of reaction rate by water produced by reaction is small. Further, since the heteropolyacid is small in corrosion resistance, stainless steel can be used and since lowering of activity is small, the above-mentioned method is economical.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for producing bisphenol by reacting a phenol with a ketone using a heteropolyacid as an acidic condensing agent.

Bisphenol, particularly bispheno-A obtained from the condensation reaction of phenol and acetone, is used as a raw material for polycarbonate resins, epoxy resins, and the like, and in recent years has been increasingly used and demanded as a raw material for engineering plastics. Highly purified bisphenol A is suitable for these applications.
is required, and an economical manufacturing process is desired.

[Prior Art] Bisphenol is usually produced by reacting excess phenol and ketone in the presence of an acidic condensing agent. In some cases, a co-catalyst such as a sulfur compound may be added. The reaction is carried out batchwise or continuously.

Although hydrochloric acid and sulfuric acid were initially used as acidic condensing agents, large-scale purification steps were required to remove these catalysts from the reaction mixture. Furthermore, the equipment had to be made of a special material with high corrosion resistance, making it uneconomical.

In order to overcome these drawbacks, acidic ion exchange resins have recently come to be used as condensing agents (Japanese Patent Publication No. 36-23334).

However, in the method using acidic ion exchange resin,
The disadvantage is that the resin has a short lifespan. Moreover, there is also the drawback that the catalytic ability is rapidly reduced due to water, which is produced stoichiometrically in almost equimolar amounts to bisphenol. For example, when phenol and acetone are reacted at a molar ratio of 6:1, the water produced by the reaction reaches 1.4% or more of the system when the acetone conversion rate is 50%. Even with this amount of water, the reaction rate of ion exchange resins can be significantly reduced.

Therefore, the reaction rate gradually slows down as the reaction progresses. Usually, in a batch system, 1
It takes more than 0 hours, and it is practically difficult to react the acetone completely. In the method described in Japanese Patent Publication No. 3B-23334, it is said that the conversion rate of acetone is preferably about 50%. In this case, a complicated post-process is required to recover unreacted acetone. Moreover, the separation cost becomes high. Furthermore, since the resulting reaction solution can contain only a low concentration of bisphenol, extra energy is required to separate excess phenol. On the other hand, there is a method in which the reaction is carried out while removing the water produced by the reaction (Japanese Unexamined Patent Publication No. 6
1-78741) has also been proposed, but the cost of recycling the dehydrating agent is high and it is not an economical method.

[Ilffg points to be solved by the invention] The purpose of the present invention is to produce bisphenol by reacting phenols and ketones without using special materials for the reaction equipment, and without causing a decrease in catalyst performance. It is an object of the present invention to provide a production method in which the reaction rate is less reduced by water produced in the reaction.

[Means for Solving the Problem] The present inventors have conducted research on a method for producing bisphenol that does not require the use of special materials in a reaction device and that reduces the reduction in catalyst performance and reaction rate due to water produced in the reaction. As a result of repeated research, it was discovered that the object could be achieved by using a certain type of novel acidic condensing agent, and the present invention was completed.

That is, in the present invention, when producing bisphenol by reacting phenols and ketones, a heteropolyacid is used as an acidic condensing agent, and the heteropolyacid is mixed with at least one oxide selected from molybdenum, tungsten, vanadium, phosphorus, silicon, This is a method for producing bisphenol, which has a structure in which oxyacids selected from arsenic and germanium are condensed, and the atomic ratio of the former to the latter is 2.5 to 12.

The heteropolyacid used as the acidic condensing agent in the present invention is usually synthesized as a compound containing about 30 water molecules as crystal water. By drying the heteropolyacid or adding water to the reaction system to increase or decrease the hydration number and contacting it with ketones and excess phenol, we investigated the bisphenol production activity. It was found that bisphenol production activity increases rapidly when the number of molecules, including coordinated water, is reduced to 40 molecules or less per molecule of heteropolyacid. Moreover, when this reaction is carried out at 100°C, 40 molecules of water are present in the reaction system for each molecule of heteropolyacid, which means that the molar ratio of phenol, ketone, and heteropolyacid is IO:1:0.1. When the reaction is carried out, approximately 5.3% or more water will be present in the system, but surprisingly, bisphenol is produced at a sufficient reaction rate, and as the reaction progresses, the amount of water in the system increases. It was found that even when the amount of water increased, the reaction rate decreased little.

The condensation reaction between ketones and phenols requires strong acidity, and it has been thought that the presence of water in the reaction system deactivates the reaction activity, so the water concentration was set at 0.5% at the beginning of the reaction.
Hereinafter, it has been carried out preferably at 0.1% or less under substantially anhydrous conditions. Therefore, in the presence of water, which is believed to inhibit the condensation reaction between ketones and phenols,
Moreover, it is surprising that the reaction proceeds at a sufficient rate even in the presence of a sufficient amount of water to reduce the acid strength of the heteropolyacid.

Although the detailed mechanism of action is unknown, it is presumed that under the reaction conditions, phenol or ketone rather than water coordinates with the heteropolyacid anion and has an activating effect.

The heteropolyacid used in the reaction preferably has a water of hydration of about 40 molecules or less, more preferably 0°, and is substantially anhydrous. For this purpose, methods such as heating to a high temperature within a range that does not thermally decompose the heteropolyacid, or maintaining it under reduced pressure at a relatively low temperature are used.

By removing the water produced in the reaction, it is possible to carry out the reaction while keeping the amount of coordinated water of the heteropolyacid low.
In order to effectively remove the water produced by the 0 reaction, which is more effective,
A method in which an adsorption-type or reactive-type dehydrating agent that does not adversely affect the reaction is brought into contact with the reaction solution, or a solvent that is azeotropic with water is coexisting in the reaction system, and water is removed by azeotropy at the same time as the reaction. This is done using methods such as:

The advantages of the present invention can be summarized as follows.

(1) Because the reaction rate decreases due to reaction product water is small,
It is possible to provide a method for producing bisphenol that can improve the ketone conversion rate and has a simple post-processing step. (
2) Heteropolyacid is less corrosive under these reaction conditions, stainless steel or the like is sufficient, and it is easy to use industrially. (3) In addition, heteropolyacids have a small decrease in activity under the reaction conditions, and are economically advantageous when carried out industrially.

The present invention will be explained in more detail below.

The heteropolyacid used in the present invention has a structure in which at least one oxide selected from molybdenum, tungsten, and vanadium is condensed with an oxyacid selected from phosphorus, silicon, arsenic, and germanium, and the atomic ratio of the former to the latter is It is 2.5-12.

Specific examples of these heteropolyacids include phosphomolybdic acid, phosphotungstic acid, phosphomolybdotungstic acid, phosphomolybdovanadate, phosphomolybdotungstovanadate, phosphotungstovanadate, phosphomolybdoniobic acid, and tungsten silicoic acid. acids, silicomolybdic acid, silicomolybdotungstic acid, siliceous buttungstovanadate, germanium tungstic acid, arsenic molybdic acid, arsenic tungstic acid, etc. Among these, phosphotungstic acid or silicotungstic acid is preferred.

Heteropolyacids can also be used in reduced form.

In addition, some of the protons of heteropolyacids can be replaced with alkali metals,
It is possible to use a heteropoly-a salt substituted with an alkaline earth metal element or the like. The substitution element is not limited to these, and it is also possible to use a wide variety of elements substituted with transition metal elements and the like. Similarly, heteropolyacids in which some of the protons are replaced with various nitrogen-containing compounds can also be used.

Depending on the amount of water coexisting in the system, the heteropolyacid exists as a solid catalyst insoluble in the reaction solution or as a soluble catalyst, and the reaction can occur in either state. When the amount of water is small, it is used as a slurry solid catalyst, but as another form of solid catalyst, it may be used in the form of being supported on a carrier.

The amount of heteropolyacid used is not particularly limited, but the amount of heteropolyacid present in the reactor is small.

Reaction rate is low. The heteropolyacid is used in an amount of o, ot-t mol, preferably in the range of 0.05 to 0.5 mol, per 1 mol of ketone.

The phenol used as a raw material in the method of the present invention must not have a substituent at the para position to the human myxyl group, but must have a substituent such as an alkyl group or halogen at the ortho or meta position. You can leave it there. Specifically, phenol, 0-cresol, -1-cresol,
0-chlorophenol, II-chlorophenol, o-
t-butylphenol, 2.6-xylenol, 2.6
Examples include -di-t-butylphenol and 0-phenylphenol. As the ketone, acetone, ethyl methyl ketone, isobutyl methyl ketone, acetophenone, cyclohexanone, 1,3-dichloroacetone, etc. are used.

The amount of phenol used per 1 mole of ketone is 2 to 50
mol, preferably within the range of 5 to 25 mol.

Since the reaction is usually carried out in the presence of an excess of phenol, the use of a solvent is not particularly required, but an inert solvent may be added to the reaction.

The reaction of phenols and ketones according to the present invention usually involves
It is carried out at 30 to 150° C. in an inert gas atmosphere under a pressure of about 5 atm to normal pressure. Preferably 60-120
It is carried out under temperature conditions of ℃. If the reaction temperature is too low, the reaction activity of the catalyst will not be sufficiently exhibited, and the reaction rate will be greatly reduced by reaction product water, resulting in an extremely slow reaction rate as the reaction progresses. Also,
If the reaction temperature is too high, for example when using phenol and acetone, the desired 2,2-bis(4-
In addition to hydroxyphenyl)propane (hereinafter abbreviated as p and p'), 2-(4-hydroxyphenyl)-2-(2-
This is not preferable because it increases the production of by-products such as hydroxyphenyl)propane (hereinafter abbreviated as o, P').

The reaction time varies depending on the amount of catalyst and reaction temperature, but for example, in the case of a batch reaction using a stirred tank reactor,
Usually it takes about 0.1 to 20 hours. In the case of a piston flow type continuous reaction using a fixed bed of catalyst, it is usually preferable to adjust the space velocity (S, V,) to about 0.1 to 10 h-''. It is also possible to further shorten the reaction time by performing the reaction while removing .

As for the reaction format, commonly used ones such as seed type and base type are used. Both batch and continuous methods are possible.

After removing the catalyst from the reaction mixture.

Bisphenol is obtained according to a conventional method. For example, crude bisphenol crystals can be recovered by distilling and separating water, low-boiling point by-products, and phenols, and then pure bisphenol can be obtained by performing known purification operations such as distillation and crystallization.

[Example] Example 1 30.08 g (320, Ommol) of phenol was placed in a 100-volume four-eye glass round-bottomed flask purged with nitrogen.
1.86 g (32,0 mmol) of acetone was charged, and phosphotungstic acid (H3P) was heated in an electric furnace at a temperature of 150 to 320°C for 3 hours to adjust the crystallization water to a constant level.
3.20 mmol of W, 204o・nH2O) was added (
For HaPWt204o/40H20, water was added to adjust the amount of crystallization water). Thereafter, the reactor was placed in an oil bath at 60° C., stirring was started, and the condensation reaction was carried out for 4 hours.

After the reaction was completed, bisphenol A and unreacted acetone in the reaction mixture were analyzed to determine the acetone conversion zone and bisphenol A selectivity, and the results shown in Table H1 were obtained.

Table 1 Comparative Example 1 The reaction was carried out in the same manner as in Example 1 except that 4.80 mmol of concentrated sulfuric acid (ratio: 11.84) was added instead of the phosphotungstic acid in Example 1. The results are shown in Table 1.

Example 2 The reaction was carried out in the same manner as in Example 1, except that the reaction temperature was 100°C. However, HaPW, 204o40HzO was used as a condensing agent. 48.3% of acetone has reacted, and 41.1% of bisphenol A has reacted as Py P' form.
%, 0*P' form was obtained in a yield of 6.1x.

Comparative Example 2 Phenol 3 in a 100 resistant glass round bottom flask
0.08 g (320, Ommol) and 7.33 g of sulfonic acid type cation exchange resin (Mitsubishi Chemical Industries, Ltd., trade name Diaion 5K-IB) were heated to 80°C and maintained at ffa for 5 hours. , 146g of acetone
(32, Ommol), and further water was added so that the amount of water in the reaction system was exactly the same as in Example 2. Then, the reactor was purged with nitrogen, placed in an oil bath at 100°C, stirring was started, and the condensation reaction was carried out for 4 hours.

After the reaction was completed, 6.0% of acetone had reacted, and 5.4% of bisphenol A was obtained as a PeP' form with a yield of 0.5% of sO*P' form.

Example 3 H45iV1204g 0H20 was used as a condensing agent in 6.
40 mmol was used, the reaction temperature was 120°C, the reaction time was 1
The reaction was carried out in the same manner as in Example 1, except that a pressure-resistant glass container was used as the reactor and the pressure was increased to 1 kg/cm2 with nitrogen gas. Bisphenol A is PyP'
The OyP' form was obtained in a yield of 80.2% and 12.8%.

Example 4 HaPMo]z04o・0H20 as a condensing agent,
Using 20 mmol, the reaction temperature was 100°C, and the reaction time was 2.
The reaction was carried out in the same manner as in Example 3 except for changing the time. Bisphenol A as PDP' form 65.2% + o,
The p' form was obtained in a yield of 11.4%.

Example 5 A reaction was carried out in the same manner as in Example 4 except that H4SiMo1z04o.0H20 was used as the condensing agent. Bisphenol A has 68.9% as PeP' form and 1 as O*P' form.
Obtained with a yield of 1.8%.

Example 6 The reaction was carried out in the same manner as in Example 4 except that HaP21'11aOe2.0H20 was used as the condensing agent.

After the reaction was completed, 93.3% of acetone had reacted.

Bisphenol A is 79.1% as FDP' form, Ot
P' form was obtained in a yield of 11.6%.

Example 7 3.2 H4GeWtz04o・0H20 as a condensing agent
Using 0 mmol, phenol 45.12 g (480,0
Example 1 except that the reaction temperature was 80°C.
The reaction was carried out in the same manner.

After the reaction was completed, 95.4% of acetone had reacted.

Bisphenol A is 81.8% as Pw P' form, O
The tP' form was obtained in a yield of 12.6%.

Examples 8 to 10 The reaction was carried out in the same manner as in Example 7 except that the condensing agents shown in Table 2 were used and the reaction temperature was 110°C. The reaction results are shown in Table H2.

1 [Table 2 [Effects] According to the method of the present invention, (1) the reduction in reaction rate due to reaction product water is small, so it is possible to improve the ketone conversion rate and to produce bisphenol with a simple post-processing step. I can provide a method. (2.) Heteropolyacid is less corrosive under these reaction conditions, stainless steel or the like is sufficient, and it is easy to use industrially. (3) In addition, heteropolyacids have a small decrease in activity under the reaction conditions, and are economically advantageous when carried out industrially.

Claims (1)

[Claims] When producing bisphenols by reacting phenols and ketones, heteropolyacids are used as acidic condensing agents,
The heteropolyacid is at least one oxide selected from molybdenum, tungsten, vanadium, phosphorus, silicon,
A method for producing bisphenol, which has a structure in which oxyacids selected from arsenic and germanium are condensed, and the atomic ratio of the former to the latter is 2.5 to 12.