JPH0532576A - Production of bisphenol a - Google Patents

Abstract

PURPOSE:To obtain 2,2-bis(4-hydroxyphenyl)propane in high yield and selectivity without using a highly corrosive catalyst such as hydrogen chloride and also with little influence of the water produced. CONSTITUTION:The objective 2,2-bis(4-hydroxyphenyl)propane(bisphenol A) can be obtained by reaction of acetone with phenol in the presence of a heteropolyacid or its salt and a mercapto group-contg. organic compound.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to the reaction of acetone with phenol (hereinafter abbreviated as PL) to give bisphenol A (2,2-bis (4-hydroxyphenyl) propane, hereinafter 4,4'-BPA. Abbreviated). 4,4′-BPA is a compound useful as an intermediate raw material for polycarbonate, polyester, epoxy resin, and a developer for thermal paper.

[0002]

2. Description of the Related Art 4,4'-BPA is usually synthesized by reacting PL and acetone in the presence of an acidic condensing agent, and a sulfur compound such as methyl mercaptan may be added as a cocatalyst. Hydrogen chloride is usually used as the acidic catalyst, but since it is highly corrosive, it requires a reactor using an expensive material in the actual production, and further purification for removing the catalyst from the reaction mixture. There were problems such as the need for a process.

Further, the method of using an acidic ion exchange resin as a catalyst (Japanese Patent Laid-Open No. 36-23334) has a drawback that the activity is lowered by water produced in the reaction,
Although a method of carrying out the reaction while removing water has been studied (Japanese Patent Laid-Open No. 61-78741), the ion exchange resin has a problem that the life of the resin is short and the cost is high.

On the other hand, Japanese Patent Laid-Open No. 2-45439 discloses that
A method for producing a bisphenol using PL and ketone as a heteropoly acid as an acidic condensing agent has been disclosed. For example, in the reaction of PL and acetone, when a large amount of water of crystallization is contained in the hetero poly acid, 60 ° C. There was a defect that the reaction was extremely slow with an acetone conversion rate of 2.5% and a yield of 2.0% in 4 hours, and it was hard to say that this reaction produced water produces an industrially produced catalyst.

[0005]

DISCLOSURE OF THE INVENTION The present invention, when producing 4,4'-BPA from PL and acetone, does not use a special material for a reactor and can achieve high selectivity and high yield in a short time. It is an object of the present invention to provide a method for producing 4,4'-BPA.

[0006]

The present inventors have made it possible to react acetone and PL in the presence of a heteropolyacid and an organic compound having a mercapto group without using corrosive hydrogen chloride. Less susceptible to the water generated in the reaction, good regioselectivity in a short time and high yield 4,4 '
-I have found a way to make BPA. Further, when a heteropolyacid salt is used, the surface area becomes larger and the activity is higher than that of a normal heteropolyacid, and it was found that the reaction proceeds in a shorter time, and the present invention was completed.

That is, the present invention is characterized in that in a method for producing 4,4'-BPA by reacting acetone with PL, the reaction is carried out in the presence of a heteropolyacid or a salt thereof and an organic compound having a mercapto group. Yes 4,4 '
-A method of manufacturing BPA. (Acetone) The acetone used in the present invention is not limited to that purified by distillation, and crude acetone obtained from the bottom liquid of the distillation column in the cumene phenol process can also be used. (Heteropoly Acid or Heteropoly Acid Salt) The heteropoly acid used in the present invention is at least one oxide selected from molybdenum, tungsten and vanadium and phosphorus,
It has a structure in which an oxy acid selected from silicon, arsenic and germanium is condensed, and the former atomic ratio to the latter is 2.5-
Twelve. Examples of these heteropolyacids include phosphotungstic acid, phosphomolybdic acid, phosphomolybdotungstic acid, phosphomolybdovanadic acid, phosphomolybdotungstovanadic acid, phosphotungstovanadic acid, phosphomolybdniobic acid, silicotungstic acid, Examples thereof include silicomolybdic acid, silicomolybdotungstic acid, silicomolybdo tungstovanadic acid, germanium tungstic acid, arsenic molybdic acid, and arsenic tungstic acid.

Also, sodium of these heteropolyacids,
Alkali metal salts such as potassium and cesium and ammonium salts can also be used, and among them, cesium salts are particularly effective. Although these heteropolyacids or heteropolyacid salts can be used as they are, activated carbon, alumina,
Those supported on a carrier such as silica-alumina or diatomaceous earth may be used.

The amount of heteropolyacid or heteropolyacid salt used is preferably 0.01 to 0.
The amount is 5 mol, particularly preferably 0.05 to 0.3 mol. (Organic compound having a mercapto group) Specific examples of the organic compound having a mercapto group include ethyl mercaptan, propyl mercaptan, butyl mercaptan and other alkyl mercaptans; mercapto carboxylic acids such as mercapto propionic acid and mercapto acetic acid; mercapto ethanol, Mercaptoalcohols such as mercaptobutanol; mercaptopyridines such as mercaptopyridine, mercaptonicotinic acid, mercaptopyridinooxide, and mercaptopyridinol; thiophenols such as thiophenol and thiocresol. Alkyl mercaptans and Mercaptocarboxylic acids are particularly preferred.

The amount of the organic compound having a mercapto group used is preferably 0.1 to 50% by weight, particularly preferably 0.5 to 30% by weight, based on acetone. (Reaction condition) The amount of PL used is 2 with respect to 1 mol of acetone.
The amount is at least mol, but is preferably 3 to 20 mol. P
When the amount of L used is 2 mol or less, the reaction is slow and, in addition to the desired 4,4′-BPA, 2- (2-hydroxyphenyl) -2- (4-hydroxyphenyl) propane (hereinafter referred to as 2 , 4′-BPA) is not preferable because the amount of by-products such as 1) and 4′-BPA) increases, and when 20 mol or more is used, the reaction rate is improved, but the recovery amount of unreacted PL is increased and the productivity is reduced. Not.

The reaction temperature is 30 to 150 ° C., preferably 4
It is 0-120 degreeC. Although the reaction time depends on the amount of catalyst and the reaction temperature, it is usually 2 to 12 hours.

[0012]

According to the method of the present invention, 4,4'-BPA can be increased in a short time without using a highly corrosive catalyst such as hydrogen chloride and with almost no influence of generated water. It can be manufactured with high yield and high selectivity.

[0013]

EXAMPLES The present invention will be described more specifically with reference to Examples and Comparative Examples below. The conversion, yield and selectivity in the text are defined by the following formulas, and quantification of 4,4'-BPA and the like was carried out by high performance liquid chromatography, and quantification of acetone and phenol was carried out by gas chromatography.

[0014]

## EQU1 ## Acetone conversion rate (%) = (amount of reacted acetone (mol) / amount of charged acetone (mol)) × 100

[0015]

## EQU00002 ## 4,4'-BPA yield (%) = (amount of 4,4'-BPA produced (mol) / amount of charged acetone (mol)). Times.100

[0016]

## EQU3 ## 4,4'-BPA selectivity (%) = (4,4'-BPA yield (%) ÷ acetone conversion (%)) × 100

[0017]

## EQU4 ## 4,4'-BPA position selectivity (%) = {4,4'-BPA (mol) ÷ (4,4'-BPA + 2,4'-BPA (mol))} × 100 (Example) 1) equipped with thermometer, reflux condenser and stirrer 1
In a 00 ml three-necked flask, 30.1 g of phenol (3
20 mmol), 1.85 g of acetone (32.0 mmo)
1) and 0.14 g of butyl mercaptan were charged, and 10
8. Dried under reduced pressure at 0 ° C. to make 6 molecules of crystal water per molecule of silicotungstic acid (H ₄ SiW ₁₂ O ₄₀ · 6H ₂ O)
2 g (3.2 mmol) was added and reacted at 60 ° C. for 6 hours. As a result, the conversion of acetone was 94.7%,
The yield of 4'-BPA is 93.1%, the selectivity of 4,4'-BPA is 98.3%, and the selectivity of 4,4'-BPA position is 9.
It was 8.5%. (Example 2) As a heteropolyacid, one proton was replaced with cesium, and the mixture was dried under reduced pressure at 100 ° C to give 7 molecules of water of crystallization per one molecule of heteropolyacid. 9.6 g (3.2 mmol) of cesium phosphotungstate The reaction was performed in exactly the same manner as in Example 1 except that As a result, the conversion of acetone was 100%, the yield of 4,4'-BPA was 97.2%, and the selectivity of 4,4'-BPA was 97.2.
%, 4,4′-BPA position selectivity was 97.3%. Example 3 The reaction was carried out in the same manner as in Example 1 except that 9.0 g (2.7 mmol) of commercially available silicotungstic acid was used as it was as a heteropolyacid without being dried under reduced pressure. As a result, the conversion rate of acetone was 98.8.
%, 4,4′-BPA yield is 86.0%, 4,4′-
The BPA selectivity was 87.0% and the 4,4'-BPA position selectivity was 95.7%. (Comparative Example 1) The reaction was carried out under the same conditions as in Example 1 except that butyl mercaptan was not added and the catalyst was not dried under reduced pressure. As a result, the conversion of acetone was 65.8.
%, 4,4'-BPA yield 36.4%, 4,4'-
The BPA selectivity was 55.3% and the 4,4′-BPA position selectivity was 89.5%. Comparative Example 2 The reaction was carried out under the same conditions as in Example 1 except that the reaction was carried out for 4 hours without adding butyl mercaptan. Acetone conversion is 11.2%, 4,4'-B
PA yield is 9.5%, 4,4'-BPA selectivity is 8
The 4.8% and 4,4′-BPA position selectivity were 85.7%. (Comparative Example 3) Instead of the heteropolyacid, a strongly acidic cation exchange resin (Amberlyst 1) was vacuum dried at 80 ° C for 5 hours.
5, manufactured by Rohm & Haas Co., Ltd.) was used, and the reaction was carried out under the same conditions as in Example 1. The conversion rate of acetone was 47.9%, and the yield of 4,4'-BPA was 46.
2%, 4,4'-BPA selectivity is 96.5%, 4,4 '
-BPA position selectivity was 98.9%.

Claims (1)

Claim: What is claimed is: 1. A method for producing bisphenol A by reacting acetone and phenol, wherein the reaction is carried out in the presence of a heteropolyacid or a heteropolyacid salt and an organic compound having a mercapto group. A method for producing bisphenol A.