JP7196438B2 - Method for producing bisphenol and method for producing polycarbonate resin - Google Patents

Description

The present invention is a method for producing bisphenol for producing bisphenol. It also relates to a method for producing a polycarbonate resin using the obtained bisphenol.
The bisphenol produced by the method of the present invention contains resin raw materials such as polycarbonate resins, epoxy resins, and aromatic polyester resins, and additives such as curing agents, color developers, anti-fading agents, and other bactericidal agents and antibacterial and antifungal agents. useful as an agent.

Bisphenol is useful as a raw material for polymeric materials such as polycarbonate resins, epoxy resins, and aromatic polyester resins. As representative bisphenols, for example, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(4-hydroxy-3-methylphenyl)propane and the like are known (Patent Document 1). Moreover, bisphenol with specified metal ion concentration and dissolved oxygen concentration and a method for producing the same are known (Patent Document 2). Furthermore, in the method of adjusting the basicity of bisphenol by adding an alkali metal compound and/or an alkaline earth metal compound, it is determined from the transesterification reaction rate when the bisphenol and the carbonic acid diester are transesterified. A method for producing bisphenol characterized by this is also known (Patent Document 3).

JP 2008-214248 A JP 2015-209490 A JP-A-11-152240

However, the bisphenols produced by the methods described in Patent Documents 1 to 3 are not always sufficient as raw materials for producing polycarbonate resins and the like by melt polymerization.
Bisphenol is also used as an optical material in some fields, such as optical polycarbonate resin, and in recent years, there is a demand for transparent bisphenol with better color tone, and it is possible to efficiently remove components that deteriorate the color tone of bisphenol. I needed a way.
In addition, as raw materials for polycarbonate resins and the like produced by melt polymerization reaction, it is important to have excellent color tone even at high temperatures, and conventional bisphenols have room for improvement.
Under such circumstances, it is an object of the present invention to provide a method for producing bisphenol that can efficiently remove components that deteriorate the color tone of bisphenol and obtain bisphenol with good color tone. Another object of the present invention is to provide a method for producing a polycarbonate resin by a melt polymerization reaction using bisphenol with improved color tone.

As a result of intensive studies to solve the above problems, the present inventors found a method for efficiently removing components that deteriorate the color tone of bisphenol, and completed the invention of a method for producing bisphenol having good color tone. reached.

（式中、Ｒ¹～Ｒ⁴は、それぞれ独立に、水素原子、ハロゲン原子、アルキル基、アルコキシ基またはアリール基を表し、Ｒ¹～Ｒ⁴の少なくとも１つは、ハロゲン原子、アルキル基、アルコキシ基またはアリール基であり、Ｒ⁵とＲ⁶は、それぞれに独立に水素原子、アルキル基、アルコキシ基、または、アリール基を表すか、あるいは、Ｒ⁵とＲ⁶とが隣接する炭素原子と一緒に結合してシクロアルキリデン基を形成してもよい。）
［３］ 前記第１の炭酸塩水溶液中の炭酸塩の含有量が、前記ビスフェノールを含有する溶液中のビスフェノール１ｇに対して０．０００１ｇ以上、０．１以下ｇであり、前記第２の炭酸塩水溶液中の炭酸塩の含有量が、前記第１の有機相中のビスフェノール１ｇに対して０．０００１ｇ以上、０．１ｇ以下である［１］または［２］に記載のビスフェノールの製造法。
［４］ 前記第１の炭酸塩水溶液及び前記第２の炭酸塩水溶液が、炭酸水素ナトリウム水溶液である［１］から［３］のいずれかに記載のビスフェノールの製造法。
［５］ 前記第１工程の前に、酸触媒の存在下、ケトン又はアルデヒドと、芳香族アルコールとを縮合させることによりビスフェノールを生成させ、前記ビスフェノールが分散したスラリーを得るビスフェノール生成工程（１Ａ）と、前記スラリーと塩基性水溶液とを加熱混合し、前記ビスフェノールを溶解させ、前記ビスフェノールを含有する混合液（ｍ１）を得る溶解工程（１Ｂ）と、前記混合液（ｍ１）を、ビスフェノールを含有する有機相（ｏ１）と水相（ｗ１）とに相分離させた後、前記水相（ｗ１）を除去し、前記有機相（ｏ１）であるビスフェノールを含有する溶液を得る相分離工程（１Ｃ）とを有する［１］から［４］のいずれかに記載のビスフェノールの製造法。
［６］ 前記酸触媒が、硫酸、塩酸、及び、塩化水素ガスからなる群より選ばれるいずれか１つである［５］に記載のビスフェノールの製造法。
［７］ 前記第１工程の前に、硫酸触媒の存在下、ケトン又はアルデヒドと、芳香族アルコールとを縮合させることによりビスフェノールを生成させ、前記ビスフェノールが分散したスラリーを得るビスフェノールの生成工程（２Ａ）と、混合後の混合液（ｍ２）が酸性となるように、前記スラリーと塩基性水溶液とを加熱混合し、前記ビスフェノールを溶解させ、前記ビスフェノールを含有する混合液（ｍ２）を得る溶解工程（２Ｂ）と、前記混合液（ｍ２）を、ビスフェノールを含有する有機相（ｏ２ａ）と水相（ｗ２ａ）とに相分離させた後、前記水相（ｗ２ａ）を除去し、前記有機相（ｏ２ａ）を得る相分離工程（２Ｃ）と、前記有機相（ｏ２ａ）と水とを混合した後、ビスフェノールを含有する有機相（ｏ２ｂ）と水相（ｗ２ｂ）とに相分離させ、前記水相（ｗ２ｂ）を除去し、前記有機相（ｏ２ｂ）であるビスフェノールを含有する溶液を得る相分離工程（２Ｄ）とを有する［１］から［６］のいずれかに記載のビスフェノールの製造法。
［８］ ［１］から［７］のいずれかに記載のビスフェノールの製造法により得られたビスフェノールを用いてポリカーボネート樹脂を製造するポリカーボネート樹脂の製造法。 That is, the gist of the present invention resides in the following [1] to [8].
[1] A solution containing bisphenol and a first aqueous carbonate solution are mixed, and then phase-separated into a first organic phase containing bisphenol and a first aqueous phase containing carbonate; After mixing the first organic phase and the second carbonate aqueous solution, the second organic phase containing bisphenol and carbonate A second step of phase separation into a second aqueous phase containing a salt, removing the second aqueous phase to obtain the second organic phase, and crystallizing the second organic phase to obtain a bisphenol A method for producing bisphenol, comprising a third step of obtaining
[2] The method for producing bisphenol according to [1], wherein the bisphenol is a compound represented by the following general formula (1).

(wherein R ¹ to R ⁴ each independently represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group or an aryl group, and at least one of R ¹ to R ⁴ is a halogen atom, an alkyl group or an alkoxy or an aryl group, wherein R ⁵ and R ⁶ each independently represent a hydrogen atom, an alkyl group, an alkoxy group, or an aryl group, or R ⁵ and R ⁶ together with the adjacent carbon atoms to form a cycloalkylidene group.)
[3] The content of carbonate in the first carbonate aqueous solution is 0.0001 g or more and 0.1 g or less per 1 g of bisphenol in the solution containing bisphenol, and the second carbonate The method for producing bisphenol according to [1] or [2], wherein the content of carbonate in the salt solution is 0.0001 g or more and 0.1 g or less per 1 g of bisphenol in the first organic phase.
[4] The method for producing bisphenol according to any one of [1] to [3], wherein the first carbonate aqueous solution and the second carbonate aqueous solution are sodium hydrogencarbonate aqueous solutions.
[5] Before the first step, bisphenol is produced by condensing a ketone or aldehyde and an aromatic alcohol in the presence of an acid catalyst to obtain a bisphenol-dispersed slurry (1A). and a dissolving step (1B) of heating and mixing the slurry and the basic aqueous solution to dissolve the bisphenol to obtain a mixed liquid (m1) containing the bisphenol; Phase separation step (1C ), the method for producing bisphenol according to any one of [1] to [4].
[6] The method for producing bisphenol according to [5], wherein the acid catalyst is any one selected from the group consisting of sulfuric acid, hydrochloric acid, and hydrogen chloride gas.
[7] Before the first step, a bisphenol production step (2A) in which a bisphenol is produced by condensing a ketone or aldehyde and an aromatic alcohol in the presence of a sulfuric acid catalyst to obtain a slurry in which the bisphenol is dispersed. ) and a dissolving step of heating and mixing the slurry and the basic aqueous solution so that the mixed solution (m2) after mixing becomes acidic, dissolving the bisphenol, and obtaining the mixed solution (m2) containing the bisphenol. (2B) and the mixed liquid (m2) are phase-separated into an organic phase (o2a) containing bisphenol and an aqueous phase (w2a), then the aqueous phase (w2a) is removed, and the organic phase ( After the phase separation step (2C) for obtaining o2a), the organic phase (o2a) and water are mixed, phase separation is performed into an organic phase (o2b) containing bisphenol and an aqueous phase (w2b), and the aqueous phase is The method for producing bisphenol according to any one of [1] to [6], further comprising a phase separation step (2D) in which (w2b) is removed to obtain a solution containing bisphenol as the organic phase (o2b).
[8] A method for producing a polycarbonate resin, wherein the bisphenol obtained by the method for producing bisphenol according to any one of [1] to [7] is used to produce a polycarbonate resin.

ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of bisphenol which can remove the component which deteriorates the color tone of bisphenol efficiently can be provided, and it is possible to manufacture bisphenol which has favorable color tone. Further, using the obtained bisphenol, a method for producing a polycarbonate resin is provided in which a melt polymerization reaction proceeds easily and a polycarbonate resin having a good color tone can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS It is a flowchart which shows the manufacturing method of the bisphenol of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a flowchart which shows an example of the suitable aspect of the manufacturing method of the bisphenol of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a flowchart which shows an example of the suitable aspect of the manufacturing method of the bisphenol of this invention.

The embodiments of the present invention will be described in detail below, but the description of the constituent elements described below is an example of the embodiments of the present invention, and the present invention does not exceed the gist thereof. is not limited to
In addition, when the expression "~" is used in this specification, it is used as an expression including numerical values or physical property values before and after it.

[Method for producing bisphenol]
In the present invention, after mixing a solution containing bisphenol and a first aqueous carbonate solution, phase separation is performed into a first organic phase containing bisphenol and a first aqueous phase containing carbonate, and a first step of removing the aqueous phase of 1 to obtain the first organic phase; mixing the first organic phase with a second aqueous carbonate solution; A second step of phase separation into a second aqueous phase containing a carbonate, removing the second aqueous phase to obtain the second organic phase, and crystallizing the second organic phase and a third step of obtaining bisphenol (see Figure 1).

A feature of the method for producing bisphenol of the present invention is that steps 1 and 2 are carried out, a solution containing bisphenol is treated with an aqueous carbonate solution twice in succession, and then crystallization is carried out in the third step, to obtain bisphenol. Since the coloring component contained in the solution containing bisphenol is presumed to be a ketone and/or aldehyde condensate, the ketone or aldehyde condensate is converted into a salt by mixing with an aqueous carbonate solution, It is assumed that it can be removed in the aqueous phase. Further, by treating the first organic phase obtained in the first step again with the second aqueous carbonate solution, the residual coloring component can be significantly reduced. This can also be seen from the fact that the color tone of the bisphenol obtained by the method for producing bisphenol of the present invention is greatly improved under high-temperature conditions (for example, 175° C.) that tend to cause coloration.

[First step]
In the first step, a solution containing bisphenol and a first aqueous carbonate solution are mixed, and then phase-separated into a first organic phase containing bisphenol and a first aqueous phase containing carbonate; It is a step of removing the first aqueous phase to obtain the first organic phase.

(Solution containing bisphenol)
A solution containing bisphenol is a solution in which bisphenol is dissolved in an organic solvent.
Bisphenol is usually a compound represented by the following general formula (1).

R ¹ to R ⁴ each independently include a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryl group and the like. Alkyl groups, alkoxy groups, and aryl groups may be substituted or unsubstituted. For example, hydrogen atom, fluoro group, chloro group, bromo group, iodo group, methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, t-butyl group, n- pentyl group, i-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, methoxy group, ethoxy group, n -propoxy group, i-propoxy group, n-butoxy group, i-butoxy group, t-butoxy group, n-pentyloxy group, i-pentyloxy group, n-hexyloxy group, n-heptyloxy group, n- octyloxy group, n-nonyloxy group, n-decyloxy group, n-undecyloxy group, n-dodecyloxy group, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group , cyclododecyl group, benzyl group, phenyl group, tolyl group, 2,6-dimethylphenyl group and the like.

Among these, at least one of R ¹ to R ⁴ is preferably a halogen atom, an alkyl group, an alkoxy group or an aryl group. In addition, if R ² and R ³ among these are sterically bulky, the condensation reaction is difficult to proceed, so at least one of R ¹ and R ⁴ is a halogen atom, an alkyl group, an alkoxy group or an aryl group. , R ² and R ³ are preferably hydrogen atoms. At least one of R ¹ and R ⁴ is an alkyl group, R ² and R ³ are more preferably hydrogen atoms, R ¹ is an alkyl group, and R ² to R ⁴ are hydrogen atoms. It is even more preferable to have

^R5 and ^R6 each independently include a hydrogen atom, an alkyl group, an alkoxy group, an aryl group, and the like. Alkyl groups, alkoxy groups, and aryl groups may be substituted or unsubstituted. For example, hydrogen atom, methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, t-butyl group, n-pentyl group, i-pentyl group, n-hexyl group , n-heptyl group, n-octyl group, 2-ethylhexyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, methoxy group, ethoxy group, n-propoxy group, i -propoxy group, n-butoxy group, i-butoxy group, t-butoxy group, n-pentyloxy group, i-pentyloxy group, n-hexyloxy group, n-heptyloxy group, n-octyloxy group, n -nonyloxy group, n-decyloxy group, n-undecyloxy group, n-dodecyloxy group, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclododecyl group, benzyl group, phenyl group, tolyl group, 2,6-dimethylphenyl group and the like.

R ⁵ and R ⁶ may be linked or bridged with each other between the two groups, and R ⁵ and R ⁶ may be linked together with adjacent carbon atoms to form a cycloalkylidene group. The cycloalkylidene group is a divalent group obtained by removing two hydrogen atoms from one carbon atom of cycloalkane. Cycloalkylidene groups in which R ⁵ and R ⁶ are bonded together with adjacent carbon atoms include, for example, cyclopropylidene, cyclobutylidene, cyclopentylidene, cyclohexylidene, 3,3,5-trimethylcyclohexylidene. , cycloheptylidene, cyclooctylidene, cyclononylidene, cyclodecylidene, cycloundecylidene, cyclododecylidene, fluorenylidene, xanthonylidene, thioxantonylidene, and the like.

Among them, as the bisphenol used in the bisphenol production method of the present invention, in the general formula (1), R ¹ to R ⁴ are each independently a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group or an aryl group, and R At least one of ¹ to R ⁴ is a halogen atom, an alkyl group, an alkoxy group or an aryl group, and each of R ⁵ and R ⁶ is independently a hydrogen atom, an alkyl group, an alkoxy group or an aryl group, or , R ⁵ and R ⁶ are preferably compounds in which the adjacent carbon atoms are joined together to form a cycloalkylidene group. More preferably, in general formula (1), R ¹ to R ⁴ are each independently a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group or an aryl group, and at least one of R ¹ and R ⁴ is a halogen an atom, an alkyl group, an alkoxy group or an aryl group, R ² and R ³ are hydrogen atoms, R ⁵ and R ⁶ are each independently a hydrogen atom, an alkyl group, an alkoxy group or an aryl group, or , R ⁵ and R ⁶ are joined together with adjacent carbon atoms to form a cycloalkylidene group. More preferably, in general formula (1), R ¹ to R ⁴ are each independently a hydrogen atom or an alkyl group, at least one of R ¹ and R ⁴ is an alkyl group, R ² and R ³ is a hydrogen atom, R ⁵ and R ⁶ are each independently a hydrogen atom, an alkyl group, an alkoxy group, or an aryl group, or R ⁵ and R ⁶ are bonded together with adjacent carbon atoms It is a compound in which a cycloalkylidene group is formed by

When the isolated bisphenol is dissolved in an organic solvent to prepare a bisphenol-containing solution, the bisphenol-containing solution is prepared so that the bisphenol content in the bisphenol-containing solution is 5% by mass or more. is preferred, and it is preferred to prepare so as to be 10% by mass or more. Also, the content of bisphenol in the solution containing bisphenol is preferably 70% by mass or less, more preferably 60% by mass or less. By adjusting the concentration within such a range, it is possible to efficiently precipitate bisphenol while suppressing the contamination of impurities during crystallization in the third step.

The organic solvent is not particularly limited as long as it can dissolve bisphenol and phase-separate from the first carbonate aqueous solution. Examples thereof include aromatic hydrocarbons, aliphatic alcohols, aliphatic hydrocarbons and esters. They can be used singly or in combination.
The organic solvent is preferably an aromatic hydrocarbon because the difference in solubility of bisphenol due to temperature is large and bisphenol is easily precipitated by utilizing the temperature difference. Aromatic hydrocarbons include toluene, xylene, and the like.
Moreover, the solution in the purification process after the production of bisphenol can also be used as the solution containing bisphenol.

(First carbonate aqueous solution)
The first carbonate aqueous solution is an aqueous solution in which carbonate is dissolved in water. Carbonates include lithium carbonate, sodium carbonate, potassium carbonate, cesium carbonate, magnesium carbonate, calcium carbonate, ammonium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate and ammonium hydrogen carbonate. Sodium carbonate or sodium hydrogen carbonate is preferred, and sodium hydrogen carbonate is more preferred, because it is industrially available at low cost.

The first carbonate aqueous solution may have a saturated concentration, a high concentration, or a low concentration. When saturated or high-concentration carbonate aqueous solution is mixed, carbonate remains in the resulting bisphenol, which may affect the polymerization reaction. Therefore, a low-concentration carbonate aqueous solution of 5% by mass or less is preferable. , is more preferably 3% by mass or less, and even more preferably 2% by mass or less. Further, if the concentration of the first carbonate aqueous solution is too low, the condensation compounds of ketones and/or aldehydes, which are coloring components contained in the bisphenol-containing solution, may not be sufficiently removed as salts. is preferably 0.1% by mass or more, more preferably 0.5% by mass or more.

The amount of the first aqueous carbonate solution used is appropriately adjusted depending on the type and concentration of the carbonate in the first aqueous carbonate solution. may not be possible. Moreover, if the amount of the first carbonate aqueous solution used is too large, it may remain in the resulting bisphenol to deteriorate the quality of the bisphenol. Therefore, the content of carbonate in the first carbonate aqueous solution is preferably 0.0001 g or more, more preferably 0.001 g or more, relative to 1 g of bisphenol contained in the bisphenol-containing solution in the first step. , more preferably 0.01 g or more. Also, the content of carbonate in the carbonate aqueous solution is preferably 0.1 g or less, more preferably 0.05 g or less, relative to 1 g of bisphenol contained in the bisphenol-containing solution in the first step.

When the solution in the purification process after bisphenol production is a solution containing bisphenol, for example, a part of the solution containing bisphenol is sampled and the bisphenol content is measured using high performance liquid chromatography. , the content of bisphenol in a solution containing bisphenol can be calculated.

In the first step, the bisphenol-containing solution is mixed with the first carbonate aqueous solution, and then allowed to stand, so that the bisphenol-containing first organic phase and the carbonate-containing first aqueous phase are mixed. Allow phase separation. Further, in order to efficiently react the coloring component and the like in the bisphenol-containing solution with the carbonate to form a salt, the first carbonate aqueous solution is added to the bisphenol-containing solution, and then the mixture is appropriately stirred. In addition, by performing the first step while the bisphenol-containing solution is heated, precipitation of bisphenol can be suppressed, and coloring components and the like in the bisphenol-containing solution can be removed more efficiently.

For example, after adding the first carbonate aqueous solution to the solution containing bisphenol, the bisphenol is removed by stirring at 50 to 90° C. for about 0.1 to 1 hour and allowing to stand for about 0.3 to 2 hours. It can phase separate into a first organic phase containing and a first aqueous phase containing carbonate. In addition, coloring components are removed in the aqueous phase, and the purity of bisphenol in the organic phase is improved.

[Second step]
In the second step, after mixing the first organic phase containing bisphenol obtained in the first step and the second aqueous carbonate solution, the second organic phase containing bisphenol and the carbonate are added. It is a step of separating into a second aqueous phase, removing the second aqueous phase, and obtaining the second organic phase.
The second step can be performed in the same manner as the first step, except that the first organic phase obtained in the first step is used instead of the bisphenol-containing solution in the first step.

As in the first step, the content of carbonate in the second carbonate aqueous solution is preferably 0.0001 g or more, more preferably 0.001 g or more, relative to 1 g of bisphenol contained in the first organic phase. More preferably 0.01 g or more. Also, the content of carbonate in the second carbonate aqueous solution is preferably 0.1 g or less, more preferably 0.05 g or less, relative to 1 g of bisphenol contained in the first organic phase.
The content of bisphenol contained in the first organic phase can be calculated, for example, based on the content of bisphenol measured by sampling a portion of the first organic phase and using high performance liquid chromatography. can.

The second aqueous carbonate solution used in the second step can be the same as the first aqueous carbonate solution used in the first step. The second aqueous carbonate solution may be the same as or different from the first aqueous carbonate solution. On the other hand, if a solution different from the first carbonate aqueous solution is used, the number of impurities that can be mixed in increases and the management becomes complicated. Therefore, the first carbonate aqueous solution and the second carbonate aqueous solution are preferably the same, more preferably the same sodium carbonate aqueous solution or the same sodium hydrogencarbonate aqueous solution, and the same sodium hydrogencarbonate solution. More preferably, an aqueous solution is used.

The second step is preferably performed once, but may be performed multiple times. That is, the step of mixing an organic phase containing bisphenol and an aqueous carbonate solution, causing phase separation, and then removing the aqueous phase may be repeated multiple times. Specifically, when the second step is performed twice, the second organic phase corresponds to the first organic phase, and after mixing the same aqueous carbonate solution as the second aqueous carbonate solution, the aqueous phase can be removed to obtain a third organic phase. This third organic phase may be used in the third step. When the second step is performed n times, the n-th organic phase obtained after the (n-1)th second step should correspond to the first organic phase. After mixing the n-th organic phase and the aqueous carbonate solution, the (n+1)-th organic phase obtained by removing the aqueous phase corresponds to the second organic phase, and the third step is n+1) may be a step of crystallizing the organic phase to obtain bisphenol.

[Third step]
The third step is a step of crystallizing the second organic phase containing bisphenol obtained in the second step to obtain bisphenol. Crystallization can be performed by a conventional method, and for example, a method using a solubility difference due to a temperature difference of bisphenol and a method of precipitating a solid by supplying a poor solvent can be applied. Since the purity of the resulting bisphenol composition decreases when a poor solvent is supplied to the second organic phase, the method using the solubility difference due to the temperature difference of bisphenol is preferred.
Examples of poor solvents include aliphatic hydrocarbons having 5 or more carbon atoms such as pentane, hexane, heptane and octane, and aromatic hydrocarbons such as benzene, toluene, ethylbenzene and xylene.

For example, the second organic phase heated to 60 to 90°C is cooled to -10 to 30°C to precipitate bisphenol. The precipitated bisphenol can be recovered by solid-liquid separation and drying or the like.

Moreover, the bisphenol obtained in the third step may be further subjected to purification such as washing with sprinkling, washing with water, crystallization, etc., depending on its use. When washing with water, after dissolving the bisphenol obtained in the third step in a solvent such as an aromatic hydrocarbon, this solution may be mixed with water and washed. For example, the bisphenol obtained in the third step may be washed with water, and the washed solution may be crystallized.

[Preferred embodiment of the method for producing bisphenol of the present invention]
The method for producing bisphenol of the present invention comprises a step of condensing a ketone or aldehyde with an aromatic alcohol to produce bisphenol, and then purifying the produced bisphenol without isolating the bisphenol. By performing the 2nd step and the 3rd step, it is possible to obtain a bisphenol with an improved color tone more easily.

Bisphenol can be obtained by condensing a ketone or aldehyde with an aromatic alcohol using an acid catalyst such as sulfuric acid as a catalyst. In order to further suppress decomposition of the bisphenol produced, bisphenol is preferably produced so as to obtain a slurry in which bisphenol is dispersed at the end of the reaction. , the second step, and the third step.
The slurry in which bisphenol is dispersed can be prepared by appropriately adjusting the type of acid catalyst, the type and amount of solvent, the reaction time, etc., so as not to completely dissolve the generated bisphenol in the reaction solution. .

[Preferred embodiment (1) of the method for producing bisphenol of the present invention]
One of the preferred embodiments of the method for producing bisphenol of the present invention is, as shown in FIG. 2, by condensing a ketone or aldehyde with an aromatic alcohol in the presence of an acid catalyst before the first step to produce bisphenol. and a bisphenol generating step (1A) of obtaining a slurry in which the bisphenol is dispersed, and heating and mixing the slurry and a basic aqueous solution to dissolve the bisphenol to obtain a mixed solution (m1) containing the bisphenol. After the dissolving step (1B) and the mixed liquid (m1) are phase-separated into an organic phase (o1) containing bisphenol and an aqueous phase (w1), the aqueous phase (w1) is removed, and the organic It is a method for producing bisphenol having a phase separation step (1C) for obtaining a solution containing bisphenol as phase (o1). That is, one of the preferred embodiments of the method for producing bisphenol of the present invention is that in the purification step after the bisphenol production step (1A), the dissolution step (1B) and the phase separation step (1C) are performed, followed by ~ A method for performing the third step, bisphenol having a bisphenol production step (1A), a dissolution step (1B), a phase separation step (1C), a first step, a second step, and a third step is the manufacturing method.

The bisphenol production step (1A), dissolution step (1B), and phase separation step (1C) are described below.

[Bisphenol production step (1A)]
The bisphenol production step (1A) is a step of producing a bisphenol by condensing a ketone or aldehyde and an aromatic alcohol in the presence of an acid catalyst to obtain a slurry in which the bisphenol is dispersed. The reaction of bisphenol is generally carried out according to Reaction Formula (2) shown below.

（式中、Ｒ¹～Ｒ⁶は、一般式（１）におけるＲ¹～Ｒ⁶と同義である。）

(In the formula, R ¹ to R ⁶ have the same definitions as R ¹ to R ⁶ in general formula (1).)

(aromatic alcohol)
The aromatic alcohol used in the bisphenol production step (1A) is usually a compound represented by general formula (3) below.

In general formula (3), R ¹ to R ⁴ are each independently a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, or an aryl group. Alkyl groups, alkoxy groups, and aryl groups may be substituted or unsubstituted. For example, hydrogen atom, fluoro group, chloro group, bromo group, iodo group, methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, t-butyl group, n- pentyl group, i-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, methoxy group, ethoxy group, n -propoxy group, i-propoxy group, n-butoxy group, i-butoxy group, t-butoxy group, n-pentyloxy group, i-pentyloxy group, n-hexyloxy group, n-heptyloxy group, n- octyloxy group, n-nonyloxy group, n-decyloxy group, n-undecyloxy group, n-dodecyloxy group, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group , cyclododecyl group, benzyl group, phenyl group, tolyl group, 2,6-dimethylphenyl group and the like.

Among these, at least one of R ¹ to R ⁴ in general formula (3) is more preferably a halogen atom, an alkyl group, an alkoxy group or an aryl group. In addition, if R ² and R ³ among these are sterically bulky, the condensation reaction is difficult to proceed, so at least one of R ¹ and R ⁴ is a halogen atom, an alkyl group, an alkoxy group or an aryl group. , R ² and R ³ are preferably hydrogen atoms. Also, R ¹ and R ⁴ are each independently a hydrogen atom or an alkyl group, at least one of R ¹ and R ⁴ is an alkyl group, and R ² and R ³ are hydrogen atoms. More preferably, R ¹ is an alkyl group and R ² to R ⁴ are hydrogen atoms.

Specifically, the aromatic alcohol is preferably cresol (a compound in which R ¹ is a methyl group and R ² to R ⁴ are hydrogen atoms in the general formula (3)) or xylenol (a compound in the general formula (3) , R ¹ and R ⁴ are methyl groups, and R ² and R ³ are hydrogen atoms), particularly preferably cresol.

(ketone or aldehyde)
The ketone or aldehyde used in the bisphenol production step (1A) is usually a compound represented by the following general formula (4).

In general formula (4), R ⁵ and R ⁶ each independently include a hydrogen atom, an alkyl group, an alkoxy group, an aryl group, or the like. Alkyl groups, alkoxy groups, and aryl groups may be substituted or unsubstituted. For example, hydrogen atom, methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, t-butyl group, n-pentyl group, i-pentyl group, n-hexyl group , n-heptyl group, n-octyl group, 2-ethylhexyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, methoxy group, ethoxy group, n-propoxy group, i -propoxy group, n-butoxy group, i-butoxy group, t-butoxy group, n-pentyloxy group, i-pentyloxy group, n-hexyloxy group, n-heptyloxy group, n-octyloxy group, n -nonyloxy group, n-decyloxy group, n-undecyloxy group, n-dodecyloxy group, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclododecyl group, benzyl group, phenyl group, tolyl group, 2,6-dimethylphenyl group and the like.

R ⁵ and R ⁶ may be linked or bridged with each other between the two groups, and R ⁵ and R ⁶ may be linked together with adjacent carbon atoms to form a cycloalkylidene group. Examples of such structures include cyclopropylidene, cyclobutylidene, cyclopentylidene, cyclohexylidene, 3,3,5-trimethylcyclohexylidene, cycloheptylidene, cyclooctylidene, cyclononylidene, and cyclodecylidene. , cycloundecylidene, cyclododecylidene, fluorenylidene, xanthonylidene, thioxantonylidene, and the like.

Specific examples of the compound represented by the general formula (4) include formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, pentanaldehyde, hexanaldehyde, heptanaldehyde, octanaldehyde, nonanaldehyde, decanealdehyde, undecanealdehyde, and dodecane. Aldehydes such as aldehydes, ketones such as acetone, butanone, pentanone, hexanone, heptanone, octanone, nonanone, decanone, undecanone, dodecanone, benzaldehyde, phenylmethylketone, phenylethylketone, phenylpropylketone, cresylmethylketone, cresylmethylketone arylalkylketones such as dilethylketone, cresylpropylketone, xylylmethylketone, xylylethylketone, xylylpropylketone; cyclopropanone, cyclobutanone, cyclopentanone, cyclohexanone, cycloheptanone, cyclooctanone; cyclic alkane ketones such as cyclononanone, cyclodecanone, cycloundecanone, cyclododecanone, and the like;

In the reaction of condensing a ketone or aldehyde with an aromatic alcohol, the molar ratio of the aromatic alcohol to the ketone or aldehyde ((moles of aromatic alcohol/moles of ketone) or (moles of aromatic alcohol/moles of aldehyde When the number of moles)) is small, ketones or aldehydes tend to be multimerized. For these reasons, the molar ratio of aromatic alcohol to ketone or aldehyde is preferably 1.5 or higher, more preferably 1.6 or higher, and even more preferably 1.7 or higher. Moreover, the upper limit is preferably 15 or less, more preferably 10 or less, and still more preferably 8 or less.

Condensation of a ketone or aldehyde with an aromatic alcohol under an acid catalyst is usually carried out by supplying a mixed solution of the aromatic alcohol and an acid catalyst with the ketone or aldehyde and allowing them to react for a certain period of time. As a method for supplying the ketone or aldehyde to the mixed solution of the aromatic alcohol and the acid catalyst, a method of supplying them all at once or a method of supplying them separately can be used. Since the reaction that produces bisphenol is an exothermic reaction, the ketone or aldehyde is preferably supplied by dividing the supply by dropping little by little.

(acid catalyst)
Examples of the acid catalyst of the present invention include sulfuric acid, hydrochloric acid, hydrogen chloride gas, phosphoric acid, aromatic sulfonic acids such as p-toluenesulfonic acid, and aliphatic sulfonic acids such as methanesulfonic acid. The acid catalyst is preferably any one selected from the group consisting of sulfuric acid, hydrochloric acid and hydrogen chloride gas. Sulfuric acid is more preferable as the acid catalyst from the viewpoints of excellent reaction efficiency, low volatility of the catalyst, and low burden on equipment.
When sulfuric acid is used, it is preferable to use sulfuric acid and an aliphatic alcohol in combination and coexist with a monoalkyl sulfate produced by the reaction of the sulfuric acid and the aliphatic alcohol because of its high acidity. As a result, the acid strength of the catalyst can be controlled, and the condensation (multimerization) and coloration of the starting ketone or aldehyde can be suppressed. Therefore, it is possible to suppress the excessive production of aromatic alcohol sulfonic acid and to easily and efficiently produce bisphenol in which the coloring of the product is reduced.

Aliphatic alcohols used in combination with sulfuric acid include, for example, methanol, ethanol, n-propanol, i-propanol, n-butanol, i-butanol, t-butanol, n-pentanol, i-pentanol, n-hexanol, Examples include alkyl alcohols having 1 to 12 carbon atoms such as n-heptanol, n-octanol, n-nonanol, n-decanol, n-undecanol, n-dodecanol, ethylene glycol, diethylene glycol and triethylene glycol. can. As the number of carbon atoms increases, the aliphatic alcohol increases in lipophilicity and becomes difficult to mix with sulfuric acid, making it difficult to obtain monoalkyl sulfate. Therefore, alkyl alcohols having 8 or less carbon atoms are preferable.

If the molar ratio of the fatty alcohol to the sulfuric acid (number of moles of fatty alcohol/number of moles of sulfuric acid) is small, the amount of monoalkyl sulfate generated will be small and the reaction will take a long time. Also, if the amount is large, the concentration of sulfuric acid will decrease, and the reaction will take a long time. For these reasons, the lower limit of the molar ratio of aliphatic alcohol to sulfuric acid is preferably 0.01 or more, more preferably 0.05 or more, and still more preferably 0.1 or more. Moreover, the upper limit is preferably 10 or less, more preferably 5 or less, and still more preferably 3 or less.

Also, when sulfuric acid is used, if the concentration of sulfuric acid used (concentration of sulfuric acid aqueous solution) is high, the self-condensation reaction of ketones or aldehydes tends to proceed, which may cause deterioration of the color tone of bisphenol and a decrease in the reaction selectivity of bisphenol. . Further, if the concentration of sulfuric acid used is low, the sulfonation of the aromatic alcohol cannot proceed, and the reaction time for producing bisphenol becomes long, making it difficult to produce bisphenol efficiently. Therefore, the concentration of sulfuric acid used is preferably 70% by mass or more, more preferably 75% by mass or more. Also, the concentration of sulfuric acid used is preferably 98% by mass or less, more preferably 90% by mass or less, and even more preferably 85% by mass or less.

(thiol)
A thiol is preferably added as a co-catalyst in the bisphenol production step (1A). Thiols to be used include, for example, mercaptocarboxylic acids such as mercaptoacetic acid, thioglycolic acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid, and 4-mercaptobutyric acid, methylmercaptan, ethylmercaptan, propylmercaptan, butylmercaptan, and pentylmercaptan. , hexyl mercaptan, heptyl mercaptan, octyl mercaptan, nonyl mercaptan, decyl mercaptan, undecyl mercaptan, dodecyl mercaptan.

In the present invention, when the molar ratio of thiol to ketone or aldehyde ((number of moles of thiol/number of moles of ketone) or (number of moles of thiol/number of moles of aldehyde)) is small, the effect of improving reaction selectivity is obtained. hard to get Moreover, when there is much, thiol may be mixed in the bisphenol obtained and quality may deteriorate. For these reasons, the molar ratio of thiol to ketone or aldehyde is preferably 0.001 or more, more preferably 0.005 or more, and still more preferably 0.01 or more. Moreover, the upper limit thereof is preferably 1 or less, more preferably 0.5 or less, and still more preferably 0.1 or less.

(solvent)
In the bisphenol production step (1A), the reaction for producing bisphenol may be carried out in the presence of a solvent such as toluene or xylene. Alternatively, an aliphatic alcohol such as methanol, ethanol, or propanol may be added to a reaction solution containing an aromatic alcohol and a ketone or aldehyde to carry out the reaction. In particular, when sulfuric acid is used as an acid catalyst as described above, the addition of an aliphatic alcohol is preferable because the addition of an aliphatic alcohol reacts with sulfuric acid to produce monoalkyl sulfate and exhibits a catalytic action.
The solvent used for the production of bisphenol can be recovered and purified by distillation or the like and reused.
Also, instead of using a solvent, a large amount of aromatic alcohol may be used instead of the solvent. Although unreacted aromatic alcohol is lost, it can be recovered and purified by distillation or the like and reused.

In the bisphenol production step (1A), the bisphenol production reaction is a condensation reaction between a ketone or aldehyde and an aromatic alcohol. When the reaction temperature of the condensation reaction is high, the multimerization of ketones or aldehydes tends to proceed. Moreover, when the reaction temperature is low, the time required for the reaction is prolonged. For these reasons, the reaction temperature is preferably -30°C or higher, more preferably -20°C or higher, and still more preferably -15°C or higher. Also, the upper limit of the reaction temperature is preferably 100° C. or lower, more preferably 80° C. or lower, and even more preferably 70° C. or lower.

In the present invention, the reaction time of the condensation reaction is preferably 30 hours or less, more preferably 25 hours or less, still more preferably 20 hours or less, because the bisphenol produced tends to decompose when the reaction time is long. The lower limit of the reaction time is usually 2 hours or more, preferably 5 hours or more, more preferably 15 hours or more.
The reaction time also includes the mixing time of the ketone or aldehyde and the aromatic alcohol. For example, when a ketone or aldehyde is supplied to a mixed solution of an aromatic alcohol and an acid catalyst over 1 hour and then reacted for 1 hour, the reaction time is 2 hours.

[Dissolving step (1B)]
In the dissolution step (1B), the bisphenol-dispersed slurry obtained in the bisphenol production step (1A) and the basic aqueous solution are heated and mixed to dissolve the bisphenol, thereby producing a mixed solution (m1) containing the bisphenol. get The mixing of the bisphenol-dispersed slurry and the basic aqueous solution is for stopping the bisphenol production reaction, and the dissolution of the bisphenol by heating is for increasing the cleaning efficiency. By heating, the bisphenol dispersed in the slurry dissolves in the solvent, unreacted aromatic alcohol, etc. in the slurry.

A basic aqueous solution is an aqueous solution in which a basic substance is dissolved in water. Basic substances include, for example, strongly basic substances such as sodium hydroxide, potassium hydroxide, and lithium hydroxide. Sodium hydroxide is preferred because it is industrially available at low cost.
The concentration of the basic aqueous solution is preferably 50% by mass or less, preferably 40% by mass or less, because if the concentration is high, the concentration of the salt produced by the reaction with the acid catalyst increases and may precipitate. In addition, when the concentration of the basic aqueous solution is low, the amount of the basic aqueous solution supplied to stop the bisphenol production reaction increases, and the volume increases and the efficiency deteriorates. is 10% by mass or more.
The amount of the basic aqueous solution is appropriately adjusted according to the amount of the acid catalyst and the concentration of the basic aqueous solution. By adjusting the amount of the basic aqueous solution, the pH of the mixed liquid (m1) obtained by mixing the slurry and the basic aqueous solution can be adjusted.

Heating and mixing of the slurry and the basic aqueous solution may be performed simultaneously or separately. For example, the slurry may be mixed with the basic aqueous solution while being heated, or the slurry and the basic aqueous solution may be mixed and then heated. On the other hand, if the slurry is heated while the acid concentration is high, the generated bisphenol is likely to be decomposed.
Further, depending on the solvent in the slurry, the amount of unreacted aromatic alcohol, the concentration of bisphenol, etc., a solvent may be added when mixing the slurry and the basic aqueous solution in order to increase the solubility of bisphenol.

The heating temperature is preferably 60 to 90°C. If the heating temperature is too high, the bisphenol tends to decompose. On the other hand, if the heating temperature is too low, the dissolution of bisphenol will be insufficient, or an excessive amount of solvent will be required to dissolve the bisphenol.

[Phase separation step (1C)]
In the phase separation step (1C), the mixed liquid (m1) obtained in the dissolution step (1B) is phase-separated into an organic phase (o1) containing bisphenol and an aqueous phase (w1), and then the water is Phase (w1) is removed to obtain a solution containing bisphenol, the organic phase (o1).
In addition, the phase separation step (1C) is performed while maintaining the temperature at the heating temperature of the dissolving step (1B) so that the bisphenol dissolved in the mixed liquid (m1) does not precipitate.
The liquid mixture (m1) can be allowed to stand for an arbitrary period of time to cause phase separation. The bisphenol produced in the bisphenol production step (1A) is dissolved in the organic phase (o1). By removing the aqueous phase (w1) and isolating the organic phase (o1), the organic phase ( o1) can be the bisphenol-containing solution of the first step.

By using the organic phase (o1) obtained in the phase separation step (1C) as a solution containing bisphenol and performing the first step and subsequent steps in the same manner as described above, bisphenol with improved color tone can be obtained more easily. be able to.

[Preferred embodiment (2) of the method for producing bisphenol of the present invention]
Also, when sulfuric acid is used as the acid catalyst in the reaction of condensing a ketone or aldehyde with an aromatic alcohol to obtain a bisphenol, an aromatic alcohol sulfonic acid is produced as a by-product. The present inventors have found that this aromatic alcohol sulfonic acid is a component that inhibits the melt polymerization reaction during the production of the polycarbonate resin. When the acid catalyst is sulfuric acid, the removal of the aromatic alcohol sulfonic acid, which is a by-product, in addition to the coloring component, not only improves the color tone, but also promotes melt polymerization during the production of the polycarbonate resin. It is easy to make, and it can be made suitable as a raw material for polycarbonate resin.

In the method for producing bisphenol of the present invention, as shown in FIG. 3, sulfuric acid is used as an acid catalyst, and a ketone or aldehyde and an aromatic alcohol are condensed to produce bisphenol. (2B) is a method in which the first step, the second step and the third step are performed after performing the phase separation step (2C) and the phase separation step (2D). By adopting such a production method, a simple production method can be achieved that can efficiently remove the aromatic alcohol sulfonic acid, which is a by-product, in addition to the coloring component.

In the method for producing bisphenol shown in FIG. 3, before the first step, bisphenol is produced by condensing a ketone or aldehyde and an aromatic alcohol in the presence of a sulfuric acid catalyst, and a slurry in which the bisphenol is dispersed is prepared. In step (2A) of producing bisphenol to be obtained, the slurry and the basic aqueous solution are heated and mixed so that the mixed solution (m2) after mixing becomes acidic, the bisphenol is dissolved, and the mixed solution containing the bisphenol is obtained. A dissolution step (2B) for obtaining (m2), and phase separation of the mixed liquid (m2) into an organic phase (o2a) containing bisphenol and an aqueous phase (w2a), and then separating the aqueous phase (w2a). is removed to obtain the organic phase (o2a), and after mixing the organic phase (o2a) and water, the organic phase (o2b) containing bisphenol and the aqueous phase (w2b) and a phase separation step (2D) of phase separation, removing the aqueous phase (w2b), and obtaining a solution containing bisphenol as the organic phase (o2b).

The bisphenol production step (2A), the dissolution step (2B), the phase separation step (2C), and the phase separation step (2D) are described below.

(Bisphenol production step (2A))
The bisphenol production step (2A) can be carried out in the same manner as the bisphenol production step (1A) using sulfuric acid as the acid catalyst.

(Dissolving step (2B))
In the dissolution step (2B), the bisphenol-dispersed slurry obtained in the bisphenol generation step (2A) and the basic aqueous solution are heated and mixed to dissolve the bisphenol, thereby producing a mixed solution (m2) containing the bisphenol. get The mixing of the bisphenol-dispersed slurry and the basic aqueous solution is for stopping the bisphenol production reaction, and the dissolution of the bisphenol by heating is for increasing the cleaning efficiency. By heating, the bisphenol dispersed in the slurry dissolves in the solvent, unreacted aromatic alcohol, etc. in the slurry.
The basic aqueous solution, mixing method, heating temperature, etc. can be performed in the same manner as in the dissolving step (1B).

Further, in the dissolving step (2B), the basic aqueous solution is mixed so that the mixed liquid (m2) after mixing becomes acidic (pH 4 or less). Specifically, the concentration and amount of the basic aqueous solution are adjusted so that the mixed solution (m2) has a pH of 4 or less.
The pH of the mixed liquid (m2) may be obtained by measuring the pH of the mixed liquid (m2) using a pH meter, or the aqueous phase removed in the next step, the phase separation step (2C). may be determined by measuring the pH of When determining the pH of the mixed liquid (m2) from the pH of the aqueous phase removed in the phase separation step (2C), which is the next step, the pH of the aqueous phase removed in the phase separation step (2C), which is the next step is 4 or less, it can be determined that the mixed liquid (m2) has a pH of 4 or less.

(Phase separation step (2C))
In the phase separation step (2C), the mixed liquid (m2) obtained in the dissolution step (2B) is phase-separated into an organic phase (o2a) containing bisphenol and an aqueous phase (w2a), and then the aqueous phase (w2a) is removed to obtain the organic phase (o2a).
In addition, the phase separation step (2C) is performed while maintaining the temperature at the heating temperature of the dissolving step (2B) so that the bisphenol dissolved in the mixed liquid (m2) does not precipitate.

Similar to the phase separation step (1C), the liquid mixture (m2) can be allowed to stand for an arbitrary period of time to cause phase separation. After phase separation, the bisphenol produced in the bisphenol producing step (2A) dissolves in the organic phase (o2a). Further, the aromatic alcohol sulfonic acid represented by the general formula (5) produced as a by-product in the bisphenol production step (2A) dissolves in the aqueous phase (w2a) because it is readily soluble in acidic water. Therefore, by removing the aqueous phase (w2a), the aromatic alcohol sulfonic acid represented by general formula (5) is efficiently removed.

（式中、Ｒ¹～Ｒ³は、一般式（３）におけるＲ¹～Ｒ³と同義である。また、Ｘは、ナトリウム原子または水素原子を表す。）

(In the formula, R ¹ to R ³ have the same definitions as R ¹ to R ³ in general formula (3). X represents a sodium atom or a hydrogen atom.)

For example, when cresol is used as the aromatic alcohol, cresol sulfonic acid represented by general formula (6) is produced as a by-product. Since the cresol sulfonic acid represented by the general formula (6) is easily dissolved in acidic water, it is removed into the aqueous phase in the phase separation step (2C).

（式中、Ｘはナトリウム原子又は水素原子を表す。）

(Wherein, X represents a sodium atom or a hydrogen atom.)

(Phase separation step (2D))
In the phase separation step (2D), after the organic phase (o2a) obtained in the phase separation step (2C) and water are mixed, phase separation is performed into an organic phase (o2b) containing bisphenol and an aqueous phase (w2b). and remove the aqueous phase (w2b) to obtain a solution containing bisphenol, which is the organic phase (o2b). That is, it is a step of washing the organic phase (o2a) with water.
In addition, the phase separation step (2D) is performed while maintaining the temperature of the phase separation step (2C) so that the bisphenol dissolved in the organic phase (o2b) does not precipitate.

After mixing water with the organic phase (o2a), the mixture can be stirred for an arbitrary period of time and allowed to stand still for phase separation. After phase separation the bisphenol dissolves in the organic phase (o2b). In addition, neutralized salts such as sulfuric acid and sodium sulfate are dissolved in the aqueous phase (w2b). Therefore, neutralizing salts such as sulfuric acid and sodium sulfate are efficiently removed by removing the aqueous phase (w2b).

By using the organic phase (o2b) obtained in the phase separation step (2D) as a solution containing bisphenol and performing the first step and subsequent steps in the same manner as described above, bisphenol with improved color tone can be obtained more easily. be able to.
Generally, in the first step, the organic phase (o2b) and the first carbonate aqueous solution are mixed so that the first organic phase becomes basic, for example, the pH of the first organic phase is 9 or more. It can be a step of mixing the organic phase (o2b) and the first carbonate aqueous solution so that the

In addition, since the aromatic alcohol sulfonic acid represented by the general formula (7) is easily dissolved in basic water, by performing the first step and the second step using the organic phase (o2b), the general The aromatic alcohol sulfonic acid represented by formula (7) can be efficiently removed. The organic phase (o2b) is made basic by mixing an aqueous carbonate solution such as sodium hydrogencarbonate, and the aqueous phase is removed under basic conditions to remove the aromatic alcohol sulfonic acid together with the coloring component.

（式中、Ｒ¹～Ｒ⁴は、一般式（３）におけるＲ¹～Ｒ⁴と同義である。また、Ｘは、ナトリウム原子または水素原子を表す。）

(In the formula, R ¹ to R ⁴ have the same definitions as R ¹ to R ⁴ in general formula (3). X represents a sodium atom or a hydrogen atom.)

For example, when cresol is used as the aromatic alcohol, cresol sulfonic acid represented by general formula (8) is produced as a by-product. Since the cresol sulfonic acid represented by the general formula (8) is easily dissolved in basic water, it is removed by the aqueous phase in the first step and the second step.

（式中、Ｘはナトリウム原子又は水素原子を表す。）

(Wherein, X represents a sodium atom or a hydrogen atom.)

As described above, when sulfuric acid is used as the acid catalyst, aromatic alcohol sulfonic acids represented by general formulas (5) and (7) are produced as by-products, but general formula (5 ) and the aromatic alcohol sulfonic acid represented by general formula (7) differ in the acidity of water in which they are easily dissolved. As in the method for producing bisphenol shown in FIG. 3, the phase separation step (2C), the phase separation step (2D), the first step and the second step are performed, and by performing purification under conditions with different acidity, the by-product Aromatic alcohol sulfonic acid, which is a substance, and sulfuric acid, which is an acid catalyst, can be efficiently removed. become a thing.

<Uses of bisphenol>
Bisphenol produced by the method for producing bisphenol of the present invention (hereinafter sometimes referred to as "the bisphenol of the present invention") can be used as optical materials, recording materials, insulating materials, transparent materials, electronic materials, adhesive materials, heat-resistant materials, Various thermoplastic resins such as polyether resins, polyester resins, polyarylate resins, polycarbonate resins, polyurethane resins, acrylic resins, epoxy resins, unsaturated polyester resins, phenolic resins, and polybenzoxazine resins. , cyanate resin, etc., as a constituent component of various thermosetting resins, a curing agent, an additive, or a precursor thereof. It is also useful as an additive such as a color developer for heat-sensitive recording materials, an anti-fading agent, a bactericide, and an antibacterial and antifungal agent.

Among these, it is preferable to use it as a raw material (monomer) for thermoplastic resins and thermosetting resins, and more preferably as a raw material for polycarbonate resins and epoxy resins, because it can impart good mechanical properties. It is also preferably used as a developer, and more preferably used in combination with a leuco dye and a discoloration temperature regulator.

[Method for producing polycarbonate resin]
In the method for producing a polycarbonate resin using the bisphenol of the present invention as a raw material, the bisphenol of the present invention and a carbonic acid diester such as diphenyl carbonate are transesterified in the presence of, for example, an alkali metal compound and/or an alkaline earth metal compound. It is a method of manufacturing by a method of making The transesterification reaction can be carried out by appropriately selecting a known method, and an example using the bisphenol and diphenyl carbonate of the present invention as raw materials will be described below.

In the above method for producing a polycarbonate resin, it is preferable to use an excess amount of diphenyl carbonate relative to the bisphenol of the present invention. The amount of diphenyl carbonate to be used relative to bisphenol is preferably large from the viewpoint that the produced polycarbonate resin has few terminal hydroxyl groups and the polymer has excellent thermal stability. In addition, it is preferable that the transesterification reaction rate is high and that the polycarbonate resin having the desired molecular weight is easily produced. For these reasons, the amount of diphenyl carbonate used per 1 mol of bisphenol is usually 1.001 mol or more, preferably 1.002 mol or more. Also, it is usually 1.3 mol or less, preferably 1.2 mol or less.

As a raw material supply method, the bisphenol and diphenyl carbonate of the present invention can be supplied in solid form, but it is preferable to melt one or both of them and supply them in a liquid state.

A catalyst is usually used when producing a polycarbonate resin by the transesterification reaction between diphenyl carbonate and bisphenol. In the above method for producing a polycarbonate resin, it is preferable to use an alkali metal compound and/or an alkaline earth metal compound as the transesterification catalyst. These may be used alone, or two or more of them may be used in any combination and ratio. Practically, it is desirable to use an alkali metal compound.

The amount of catalyst used per 1 mol of bisphenol or diphenyl carbonate is usually 0.05 μmol or more, preferably 0.08 μmol or more, more preferably 0.10 μmol or more. Also, it is usually 100 μmol or less, preferably 50 μmol or less, more preferably 20 μmol or less.

When the amount of the catalyst used is within the above range, it is easy to obtain the polymerization activity necessary for producing a polycarbonate resin having a desired molecular weight, and the polymer hue is excellent, and excessive branching of the polymer does not proceed, It is easy to obtain a polycarbonate resin with excellent fluidity during molding.

In order to produce a polycarbonate resin by the above method, it is preferable to continuously supply both the above raw materials to a raw material mixing tank, and continuously supply the resulting mixture and a transesterification catalyst to a polymerization tank.
In the production of a polycarbonate resin by the transesterification method, both raw materials supplied to a raw material mixing tank are generally stirred uniformly and then fed to a polymerization tank in which a catalyst is added to produce a polymer.

The bisphenol of the present invention does not contain a component that inhibits the melt polymerization reaction and has a good color tone, so that a polycarbonate resin with a good color tone can be produced.

EXAMPLES The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited by the following examples as long as the gist thereof is not exceeded.

[Raw materials and reagents]
Orthocresol, toluene, sodium hydroxide, sulfuric acid, dodecanethiol, methanol, acetone, sodium bicarbonate (sodium bicarbonate), bisphenol C, and cesium carbonate were reagents manufactured by Wako Pure Chemical Industries, Ltd.
A product manufactured by Mitsubishi Chemical Corporation was used as diphenyl carbonate.

[analysis]
<Composition of solution (organic phase) during production of bisphenol C and analysis of cresol sulfonic acid>
Composition analysis and cresol sulfonic acid analysis of the solution (organic phase) during the production of bisphenol C were performed by high performance liquid chromatography under the following procedures and conditions.
・ Apparatus: LC-2010A manufactured by Shimadzu Corporation, Imtakt Scherzo SM-C18 3 μm 150 mm × 4.6 mm ID
・Low pressure gradient method ・Analysis temperature 40℃
・Eluent composition:
A solution: ammonium acetate: acetic acid: demineralized water = 3.000 g: 1 mL: 1 L solution B solution: ammonium acetate: acetic acid: acetonitrile = 1.500 g: 1 mL: 900 mL solution ・Analysis time 0 minutes: solution A: solution B = 60 : 40 (volume ratio, hereinafter the same.)
Analysis time 0 to 25 minutes gradually change the eluent composition to A solution: B solution = 90: 10,
Analysis time 25 to 30 minutes is maintained at A solution: B solution = 90: 10,
Analysis was performed at a flow rate of 0.8 mL/min and a detection wavelength of 280 nm.

<Sodium atom concentration and chlorine atom concentration contained in bisphenol C>
The concentration of sodium atoms contained in bisphenol C was determined by the following procedure. Nitric acid was added to bisphenol C, and pressure-sealed decomposition was performed using a microwave decomposition apparatus. The resulting decomposed solution was diluted with pure water, and the concentration of sodium atoms contained in bisphenol C was measured using ELEMENT 2 manufactured by Thermo Fisher Scientific.

The chlorine atom concentration contained in bisphenol C was determined by the following procedure. Bisphenol C is burned using a Mitsubishi Chemical fixed-bed semi-batch combustion apparatus (QF-02), the combustion gas is absorbed by the absorbing liquid, and the ions in the absorbing liquid are removed by Thermo Fisher Scientific's DX-500. The chlorine atom concentration contained in bisphenol C was measured using a Dionex column (Ion Pac AS12A) and an eluent (sodium carbonate 2.7 mmol/L + sodium hydrogen carbonate 0.3 mmol/L).

<Measurement of Hazen color number>
The Hazen color number of bisphenol C when melted was measured using a color difference meter under the following procedures and conditions.
A test tube (24 mm×200 m/m P-24) manufactured by Nippon Rika Glass Co., Ltd. was used as the test tube for the spectral color difference meter.
As an apparatus, "SE-6000" manufactured by Nippon Denshoku Industries Co., Ltd. was used.
The Hazen color number was measured by heating a spectrocolorimeter test tube containing bisphenol C at a predetermined temperature with an aluminum block heater, and performing the measurement within 30 seconds at the predetermined time.
Further, the Hazen color number of the solution (organic phase) during the production of bisphenol C was measured using a color difference meter under the following procedures and conditions.
A test tube (24 mm×200 m/m P-24) manufactured by Nippon Rika Glass Co., Ltd. was used as the test tube for the spectral color difference meter.
As an apparatus, "SE-6000" manufactured by Nippon Denshoku Industries Co., Ltd. was used.
The Hazen color number was measured within 1 minute after the obtained organic phase was placed in a test tube for spectrocolorimeter.

<Viscosity average molecular weight>
Viscosity average molecular weight (Mv) is obtained by dissolving polycarbonate resin in methylene chloride (concentration 6.0 g / L), measuring specific viscosity (ηsp) at 20 ° C. using Ubbelohde viscosity tube, viscosity average molecular weight according to the following formula (Mv) was calculated.
ηsp/C=[η](1+0.28ηsp)
[η]=1.23×10 ⁻⁴ Mv ^0.83

<Terminal hydroxyl group concentration of polycarbonate resin>
The terminal hydroxyl group concentration (OH) concentration of the polycarbonate resin was measured by colorimetry according to the titanium tetrachloride/acetic acid method (see Makromol. Chem. 88, 215 (1965)).

<Pellet YI>
The pellet YI (transparency of polycarbonate resin) was evaluated by measuring the YI value (yellowness index value) of polycarbonate resin pellets in reflected light according to ASTM D1925. A spectrophotometer CM-5 manufactured by Konica Minolta Co., Ltd. was used as an apparatus, and a measurement diameter of 30 mm and SCE were selected as measurement conditions. A calibration glass CM-A212 for petri dish measurement was fitted into the measurement part, and a zero calibration box CM-A124 was placed over it to perform zero calibration, followed by white calibration using a built-in white calibration plate. Next, measurement was performed using a white calibration plate CM-A210, L * was 99.40 ± 0.05, a * was 0.03 ± 0.01, b * was -0.43 ± 0.01, YI was -0.58±0.01. The pellets were measured by packing them into a cylindrical glass container having an inner diameter of 30 mm and a height of 50 mm to a depth of about 40 mm. The operation of taking out the pellets from the glass container and measuring again was repeated twice, and the average value of the measured values of a total of three times was used.

<Production Example 1>
92 g (0.85 mol) of orthocresol, 36 g (0.62 mol) of acetone, 12 g of toluene, and 4 g of 3-mercaptopropionic acid were placed in a jacketed separable flask equipped with a dropping funnel, thermometer, stirrer and condenser. The internal temperature was adjusted to 20°C. 94 g of 35% by mass hydrochloric acid was added to the dropping funnel and slowly added dropwise while stirring so that the internal temperature did not exceed 25°C. Next, 20 g of 98% by mass sulfuric acid was slowly added dropwise while stirring so that the internal temperature did not exceed 25°C. After that, the mixture was stirred for 5 hours while maintaining the temperature at 25°C.

After that, 80 g of desalted water and 170 g of toluene were added, and the mixture was stirred until it became a slurry, and then the internal temperature was raised to 80°C. After reaching 80° C., the mixture was allowed to stand and the lower aqueous phase was removed.
Further, a saturated sodium bicarbonate aqueous solution was added and stirred, and after allowing to stand still, the lower aqueous phase was removed. Demineralized water was added to the obtained organic phase, and the mixture was stirred until the internal temperature reached 80° C., left to stand, and then the lower aqueous phase was removed. The resulting organic phase was a yellow-green solution. After cooling the organic phase from 80° C. to 5° C., solid-liquid separation was performed by vacuum filtration. The obtained cake was washed with toluene and dried to obtain 82 g of bisphenol C(i).

20 g of the obtained bisphenol C(i) was placed in a test tube for a spectrocolorimeter and placed in an aluminum block heater set at 175° C. to prepare a melt. Five minutes after confirming the complete melting, the melt was measured with a color difference meter and found to have a Hazen color number (APHA) of 65.

<Production Example 2>
92 g (0.85 mol) of orthocresol, 36 g (0.62 mol) of acetone, 12 g of toluene, and 4 g of 3-mercaptopropionic acid were placed in a jacketed separable flask equipped with a dropping funnel, thermometer, stirrer and condenser. The internal temperature was adjusted to 20°C. 104 g of 35% by mass hydrochloric acid was added to the dropping funnel, and slowly added dropwise while stirring so that the internal temperature did not exceed 25°C. After that, the mixture was stirred for 5 hours while maintaining the temperature at 25°C.

After that, 80 g of desalted water and 170 g of toluene were added, and the mixture was stirred until it became a slurry, and then the internal temperature was raised to 80°C. After reaching 80° C., the mixture was allowed to stand and the lower aqueous phase was removed.
Further, a saturated sodium bicarbonate aqueous solution was added and stirred, and after allowing to stand still, the lower aqueous phase was removed. Demineralized water was added to the obtained organic phase, and the mixture was stirred until the internal temperature reached 80° C., left to stand, and then the lower aqueous phase was removed. The resulting organic phase was a yellow-green solution. After cooling the organic phase from 80° C. to 5° C., solid-liquid separation was performed by vacuum filtration. The obtained cake was washed with toluene and dried to obtain 87 g of bisphenol C(ii).

20 g of the obtained bisphenol C(ii) was placed in a test tube for a spectrocolorimeter and placed in an aluminum block heater set at 175° C. to prepare a melt. Five minutes after confirming complete melting, the melt was measured with a color difference meter to find that the Hazen color number (APHA) was 55.

<Production Example 3>
92 g (0.85 mol) of orthocresol, 36 g (0.62 mol) of acetone, 12 g of toluene, and 4 g of 3-mercaptopropionic acid were placed in a jacketed separable flask equipped with a dropping funnel, thermometer, stirrer and condenser. The internal temperature was adjusted to 20°C. 104 g of 98% by mass sulfuric acid was slowly added dropwise to the dropping funnel while stirring so that the internal temperature did not exceed 25°C. After that, the mixture was stirred for 5 hours while maintaining the temperature at 25°C.

After that, 80 g of desalted water and 170 g of toluene were added, and the mixture was stirred until it became a slurry, and then the internal temperature was raised to 80°C. After reaching 80° C., the mixture was allowed to stand and the lower aqueous phase was removed.
Further, a saturated sodium bicarbonate aqueous solution was added and stirred, and after allowing to stand still, the lower aqueous phase was removed. Demineralized water was added to the obtained organic phase, and the mixture was stirred until the internal temperature reached 80° C., left to stand, and then the lower aqueous phase was removed. The resulting organic phase was a yellow-green solution. After cooling the organic phase from 80° C. to 5° C., solid-liquid separation was performed by vacuum filtration. The obtained cake was washed with toluene and dried to obtain 9 g of bisphenol C (iii).

81 g of bisphenol C (iii) was obtained by repeating the same process 9 times.

[Color tone when melted]
20 g of the obtained bisphenol C (iii) was placed in a test tube for a spectral colorimeter, and placed in an aluminum block heater set at 175° C. to prepare a melt. Five minutes after confirming the complete melting, the melt was measured with a color difference meter to find a Hazen color number (APHA) of 80.

<Production Example 4>
[Preparation of solution containing bisphenol]
30 g of bisphenol C(i) obtained in Production Example 1 and 270 g of toluene were placed in a jacketed separable flask equipped with a dropping funnel, a thermometer, a stirrer and a condenser, and the temperature was raised to 80° C. to obtain bisphenol. C(i) was dissolved to obtain a toluene solution (1A) containing bisphenol.

[Production of bisphenol]
(First step)
To the obtained toluene solution (1A), 100 mL of 1.5% by mass aqueous sodium hydrogen carbonate solution was added, and while the temperature was maintained at 80°C, the mixture was stirred for 30 minutes and allowed to stand still for 30 minutes to separate the organic phase and the aqueous phase. Phase separated. The aqueous phase was then removed to obtain a toluene solution (1B) containing bisphenol (first organic phase).

(Second step)
To the obtained toluene solution (1B), 100 mL of 1.5% by mass aqueous sodium bicarbonate solution was added, and the mixture was stirred for 30 minutes while maintaining the temperature at 80° C., and allowed to stand still for 30 minutes to separate into an organic phase and an aqueous phase. let me The aqueous phase was then removed to give a toluene solution (1C) containing bisphenol (second organic phase).

(Third step)
The obtained toluene solution (1C) was cooled from 80° C. to 10° C. to precipitate bisphenol, followed by solid-liquid separation by filtration under reduced pressure.
The resulting cake was washed with toluene and dried to obtain 25 g of bisphenol C (IA).

[Color tone when melted]
20 g of the obtained bisphenol C (IA) was placed in a test tube for a spectral colorimeter, and placed in an aluminum block heater set at 175° C. to prepare a melt. Five minutes after confirming the complete melting, the melt was measured with a color difference meter and found to have a Hazen color number (APHA) of 20.

<Production Example 5>
In Production Example 5, crystallization from the bisphenol-containing toluene solution (1B) (first organic phase) obtained in the first step (“the third step”) was carried out without performing the second step of Production Example 4. ”) to obtain bisphenol.

[Preparation of solution containing bisphenol]
A toluene solution (1A) containing bisphenol was prepared in the same manner as in Production Example 4 using bisphenol C(i).

[Production of bisphenol]
(First step)
To the obtained toluene solution (1A), 100 mL of 1.5% by mass aqueous sodium bicarbonate solution was added, and the mixture was stirred for 30 minutes while maintaining the temperature at 80°C, allowed to stand still for 30 minutes, and separated into an organic phase and an aqueous phase. rice field. The aqueous phase was then removed to obtain a toluene solution (1B) containing bisphenol (first organic phase).

(3rd' process)
The obtained toluene solution (1B) was cooled from 80° C. to 10° C. to precipitate bisphenol, followed by solid-liquid separation by filtration under reduced pressure.
The resulting cake was washed with toluene and dried to obtain 25 g of bisphenol C (Ia).

[Color tone when melted]
20 g of the obtained bisphenol C (Ia) was placed in a test tube for a spectrocolorimeter and placed in an aluminum block heater set at 175° C. to prepare a melt. Five minutes after confirming the complete melting, the melt was measured with a color difference meter and found to have a Hazen color number (APHA) of 60.

<Production Example 6>
[Preparation of solution containing bisphenol]
A toluene solution (2A) containing bisphenol was obtained in the same manner as in Production Example 4, except that 30 g of bisphenol C(ii) obtained in Production Example 2 was used instead of 30 g of bisphenol C(i). .

[Production of bisphenol]
Bisphenol C (IIA) was obtained in the same manner as in Production Example 4, except that the toluene solution (2A) was used instead of the toluene solution (1A).

[Color tone when melted]
20 g of the obtained bisphenol C (IIA) was placed in a test tube for a spectrocolorimeter and placed in an aluminum block heater set at 175° C. to prepare a melt. Five minutes after confirming the complete melting, the melt was measured with a color difference meter and found to have a Hazen color number (APHA) of 20.

<Production Example 7>
[Preparation of solution containing bisphenol]
A toluene solution (2A) containing bisphenol was prepared in the same manner as in Production Example 6 using bisphenol C(ii).

[Production of bisphenol]
Bisphenol C (IIa) was obtained in the same manner as in Production Example 5, except that the toluene solution (2A) was used instead of the toluene solution (1A).

[Color tone when melted]
20 g of the obtained bisphenol C (IIa) was placed in a test tube for a spectrocolorimeter and placed in an aluminum block heater set at 175° C. to prepare a melt. Five minutes after confirming the complete melting, the melt was measured with a color difference meter, and the Hazen color number (APHA) was 50.

<Production Example 8>
[Preparation of solution containing bisphenol]
A toluene solution (3A) containing bisphenol was obtained in the same manner as in Production Example 4, except that 27 g of bisphenol C (iii) obtained in Production Example 3 was used instead of 30 g of bisphenol C (i). .

[Production of bisphenol]
Bisphenol C (IIIA) was obtained in the same manner as in Production Example 4, except that the toluene solution (3A) was used instead of the toluene solution (1A).

[Color tone when melted]
20 g of the obtained bisphenol C (IIIA) was placed in a test tube for a spectral colorimeter, and placed in an aluminum block heater set at 175°C to prepare a melt. Five minutes after confirming complete melting, the melt was measured with a color difference meter to find that the Hazen color number (APHA) was 30.

<Production Example 9>
[Preparation of solution containing bisphenol]
A toluene solution (3A) containing bisphenol was prepared in the same manner as in Production Example 8 using bisphenol C (iii).

[Production of bisphenol]
Bisphenol C (IIIa) was obtained in the same manner as in Production Example 5, except that the toluene solution (3A) was used instead of the toluene solution (1A).

[Color tone when melted]
20 g of the obtained bisphenol C (IIIa) was placed in a test tube for a spectrocolorimeter and placed in an aluminum block heater set at 175° C. to prepare a melt. Five minutes after confirming the complete melting, the melt was measured with a color difference meter and found to have a Hazen color number (APHA) of 70.

[Production Example 10]
[Preparation of solution containing bisphenol]
A toluene solution (4A) containing bisphenol was obtained in the same manner as in Production Example 4, except that commercially available bisphenol C was used instead of 30 g of bisphenol C(i).
The Hazen (APHA) of the commercial bisphenol C used was 50 when the color tone at the time of melting was measured in the same manner as described above.

[Production of bisphenol]
Bisphenol C (IV) was obtained in the same manner as in Production Example 4, except that the toluene solution (4A) was used instead of the toluene solution (1A).

[Color tone when melted]
20 g of the obtained bisphenol C(IV) was placed in a test tube for a spectrocolorimeter and placed in an aluminum block heater set at 175° C. to prepare a melt. Five minutes after confirming the complete melting, the melt was measured with a color difference meter and found to have a Hazen color number (APHA) of 20.

Table 2 shows a summary of the type of bisphenol C used as a raw material, the color tone of bisphenol C used as a raw material, the presence or absence of the first to third steps, and the color tone of the obtained bisphenol C in Production Examples 4 to 10. .

As can be seen from Table 1, by adopting the method for producing bisphenol of the present invention in which the first to third steps are performed, the color tone of the obtained bisphenol C is improved regardless of the type of bisphenol C used as a raw material. Understand.

<Production Example 11>
(Bisphenol production step (1A))
A coolant of −10° C. was passed through the jacket of a full-jacketed 1 L separable flask equipped with a thermometer, a stirrer and a 100 mL dropping funnel. Under a nitrogen atmosphere, 240 g of toluene, 9 g of methanol, and 172.5 g (1.60 mol) of orthocresol were added thereto, and the internal temperature was cooled to -5°C. After that, 67.5 g of 98% by weight sulfuric acid was added. A mixture of 4.1 g dodecanethiol and 45.8 g (0.79 mol) acetone was added to the dropping funnel. When the internal temperature of the separable flask reached -5°C, the mixture was slowly added dropwise over 1 hour. After dropping, the mixture was stirred at 10° C. for 1 hour, then heated to 45° C. and stirred at 45° C. for 1 hour to obtain a slurry (1) in which the generated bisphenol was dispersed.

(Dissolving step (1B))
128 g of a 28% by mass sodium hydroxide aqueous solution was added to the resulting slurry (1). Furthermore, while raising the temperature to 80° C., a 28 mass % sodium hydroxide aqueous solution was added so that the pH would be between 5 and 8, and the bisphenol in the slurry was dissolved in toluene.

(Phase separation step (1C)) (Preparation of solution containing bisphenol)
After the internal temperature reaches 80° C., the mixture is allowed to stand still for phase separation, and after confirming that the bisphenol precipitated during the reaction has dissolved in the organic phase, the lower aqueous phase is extracted, and the organic phase (5A) is separated. Obtained.

(First step)
While maintaining the temperature at 80° C., 1.5% by mass aqueous sodium hydrogencarbonate solution was added to the organic phase (5A), mixed and washed, and then the aqueous phase was removed to obtain an organic phase (5B). In addition, coloration was observed in the aqueous phase obtained by visual observation.

(Second step)
While maintaining the temperature at 80° C., a 1.5% by mass aqueous sodium hydrogen carbonate solution was further added to the organic phase (5B), mixed, washed, and then the aqueous phase was removed to obtain an organic phase (5C). . No coloration was observed in the aqueous phase.

(Third step)
Crystallization was performed by lowering the internal temperature of the organic phase (5C) from 80°C to 10°C, followed by solid-liquid separation using a centrifuge.

The whole amount of the obtained cake and 280 g of toluene were placed in a full-jacket 1 L separable flask equipped with a thermometer and a stirrer, and the temperature was raised to 80° C. to dissolve. The resulting solution was washed with water, the internal temperature was lowered to 10°C, and after crystallization, solid-liquid separation was performed using a centrifuge. 150 g of bisphenol C(V) was obtained by drying for hours.

[Color tone when melted]
20 g of the obtained bisphenol C(V) was placed in a test tube for a spectrocolorimeter and placed in an aluminum block heater set at 175° C. to prepare a melt. Five minutes after confirming the complete melting, the melt was measured with a color difference meter and found to have a Hazen color number (APHA) of 25.

(Manufacture of polycarbonate resin)
100 g (0.39 mol) of the obtained bisphenol C(V), 86.5 g (0.4 mol) of diphenyl carbonate and 400 mass ppm 479 μL of an aqueous cesium carbonate solution was added. The reaction vessel made of glass was evacuated to about 100 Pa, and then the operation of restoring the pressure to atmospheric pressure with nitrogen was repeated three times to replace the inside of the reaction vessel with nitrogen. After that, the reactor was immersed in an oil bath at 200° C. to dissolve the contents.

The rotation speed of the stirrer was set to 100 times per minute, and the pressure in the reaction vessel was increased to absolute pressure over 40 minutes while distilling off the phenol by-product of the oligomerization reaction of bisphenol C and diphenyl carbonate in the reaction vessel. The pressure was reduced from 101.3 kPa to 13.3 kPa. Subsequently, the pressure in the reactor was maintained at 13.3 kPa, and transesterification was carried out for 80 minutes while further distilling off phenol. Thereafter, the external temperature of the reaction vessel was raised to 250° C., and the internal pressure of the reaction vessel was reduced from 13.3 kPa to 399 Pa in absolute pressure over 40 minutes to remove distilled phenol out of the system.

Thereafter, the external temperature of the reaction vessel was raised to 280° C., the absolute pressure of the reaction vessel was reduced to 30 Pa, and a polycondensation reaction was carried out. The polycondensation reaction was terminated when the agitator in the reaction tank reached a predetermined stirring power.

Next, the pressure in the reactor was restored to 101.3 kPa in terms of absolute pressure with nitrogen, and then increased to 0.2 MPa in terms of gauge pressure.

After that, the strand was pelletized using a rotary cutter to obtain a polycarbonate resin in the form of pellets.

The viscosity average molecular weight (Mv) of the polycarbonate resin was 25,000. The pellet YI was 12.0.

<Production Example 12>
(Bisphenol production step (1A))
A separable flask equipped with a thermometer, a dropping funnel, a jacket and an anchor-type stirring blade was charged with 5 g of methanol and 235 g (2.2 mol) of orthocresol under a nitrogen atmosphere, and then 250 g of 80% by mass sulfuric acid was slowly added, The mixture was stirred for 1 hour while maintaining the temperature at 30°C. No coloring was observed in the resulting mixture of methanol, orthocresol and sulfuric acid. 250 g of toluene, 7.5 g of dodecanethiol, and 61 g (1.1 mol) of acetone were added to the dropping funnel to prepare an acetone mixture, and the acetone mixture was slowly dropped into the separable flask over 1 hour using the dropping funnel. supplied. After the acetone mixture was added dropwise, it was allowed to mix for an additional 30 minutes. After that, the reaction temperature was raised to 45° C. over 30 minutes.

(Dissolving step (1B))
After completion of the reaction, 60.0 g of toluene and 540 g of a 28% sodium hydroxide aqueous solution were supplied, and the temperature was raised to 80°C. After reaching 80°C, the mixture was allowed to stand still for phase separation, and after confirming that the bisphenol precipitated during the reaction had dissolved in the organic phase, stirring was resumed, and the pH was adjusted while adding a 28% aqueous sodium hydroxide solution. 10.5.

(Phase separation step (1C)) (Preparation of solution containing bisphenol)
Thereafter, the mixture was allowed to stand while maintaining the temperature at 80° C. for phase separation, and the lower aqueous phase was removed to obtain an organic phase (6A).

(First step)
While maintaining the temperature at 80° C., 120 g of a 1.5% by mass sodium hydrogen carbonate solution is added to the obtained organic phase (6A), mixed and allowed to stand, the lower aqueous phase is extracted, and the organic phase (6B) got

(Second step)
While maintaining the temperature at 80° C., 120 g of a 1.5% by mass sodium hydrogencarbonate solution was added to the obtained organic phase (6B), stirred, and allowed to stand, the aqueous phase was extracted, and the organic phase (6C) got

A part of the obtained organic phase (6C) was taken out and the composition of the organic phase was confirmed by high performance liquid chromatography. area %.

(Third step)
The organic phase (6C) was cooled to 80-30° C. and when 30° C. was reached, 1 g of seed crystal bisphenol C was added to confirm precipitation. After that, by cooling to 10° C., bisphenol was further precipitated.

After reaching 10°C, solid-liquid separation was performed using a centrifuge to obtain bisphenol (VI') as a wet cake.

The whole amount of bisphenol (VI') and 373 g of toluene were placed in a 1 L full-jacketed separable flask equipped with a thermometer and a stirrer, and the temperature was raised to 80°C. After confirming that a homogeneous solution was obtained, the organic phase was thoroughly washed with 600 g of desalted water three times, and the aqueous phase was removed. The resulting organic phase was cooled from 80°C to 10°C. Thereafter, filtration was performed using a centrifuge (3000 rpm for 10 minutes) to obtain wet bisphenol C. Using an evaporator equipped with an oil bath, 179 g of white bisphenol C (VI) was obtained by distilling off the low-boiling components under reduced pressure at an oil bath temperature of 100°C.

The resulting bisphenol C (VI) contained 30 mass ppm of cresol sulfonic acid and 28 mass ppm of sodium atoms.

[Color tone when melted]
20 g of the obtained bisphenol C (VI) was placed in a test tube for a spectral colorimeter, and placed in an aluminum block heater set at 175°C to prepare a melt. Five minutes after confirming the complete melting, the melt was measured with a color difference meter and found to have a Hazen color number (APHA) of 20.

<Production Example 13>
(Bisphenol production step (2A))
A separable flask equipped with a thermometer, a dropping funnel, a jacket and an anchor-type stirring blade was charged with 5 g of methanol and 235 g (2.2 mol) of orthocresol under a nitrogen atmosphere, and then 250 g of 80% by mass sulfuric acid was slowly added, The mixture was stirred for 1 hour while maintaining the temperature at 30°C. No coloring was observed in the resulting mixture of methanol, orthocresol and sulfuric acid. 250 g of toluene, 7.5 g of dodecanethiol, and 61 g (1.1 mol) of acetone were added to the dropping funnel to prepare an acetone mixture, and the acetone mixture was slowly dropped into the separable flask over 1 hour using the dropping funnel. supplied. After the acetone mixture was added dropwise, it was allowed to mix for an additional 30 minutes. After that, the reaction temperature was raised to 45° C. over 30 minutes.

(Dissolving step (2B))
After completion of the reaction, 60.0 g of toluene and 350 g of a 28% sodium hydroxide aqueous solution were supplied, and the temperature was raised to 80° C. to dissolve the bisphenol dispersed in the slurry. The pH of the aqueous phase was <1.

(Phase separation step (2C))
After reaching 80°C, the mixture was allowed to stand still for phase separation, and after confirming that the bisphenol precipitated during the reaction was dissolved in the organic phase, the lower aqueous phase was extracted to obtain an organic phase (7A).
A portion of the organic phase (7A) was taken out into a test tube for a spectral color difference meter, and the Hazen color number was measured with a spectral color difference meter.

(Phase separation step (2D)) (Preparation of solution containing bisphenol)
While maintaining the temperature at 80° C., 400 g of demineralized water was added to the resulting organic phase (7A), mixed for 30 minutes and allowed to stand, the aqueous phase was removed, and an organic phase (7B) was obtained.
A part of the organic phase (7B) was taken out into a test tube for a spectral color difference meter, and the Hazen color number was measured with a spectral color difference meter.

(First step)
While maintaining the temperature at 80° C., 120 g of a 1.5% by mass sodium hydrogen carbonate solution was added to the obtained organic phase (7B), and it was confirmed that the pH of the aqueous phase of the lower phase was 9 or higher. The aqueous phase was withdrawn to give an organic phase (7C).
A part of the organic phase (7C) was taken out into a test tube for a spectral color difference meter, and the Hazen color number was measured with a spectral color difference meter.

(Second step)
While maintaining the temperature at 80° C., 120 g of a 1.5% by mass sodium bicarbonate solution was further added to the obtained organic phase (7C), and after stirring, the mixture was allowed to stand, the aqueous phase was extracted, and the organic phase (7D) got
A part of the organic phase (7D) was taken out into a test tube for a spectral color difference meter, and the Hazen color number was measured with a spectral color difference meter.

A part of the obtained organic phase (7D) was taken out and the composition of the organic phase was confirmed by high performance liquid chromatography. area %.

(Third step)
The organic phase (7D) was cooled to 80-30°C and when 30°C was reached, 1 g of seed bisphenol C was added to check for precipitation. After that, by cooling to 10°C, bisphenol was further precipitated.

After reaching 10°C, solid-liquid separation was performed using a centrifuge to obtain bisphenol (VII') as a wet cake.

The whole amount of bisphenol (VII') and 373 g of toluene were placed in a full-jacketed 1 L separable flask equipped with a thermometer and a stirrer, and the temperature was raised to 80°C. After confirming that a homogeneous solution was obtained, the organic phase was thoroughly washed with 600 g of desalted water three times, and the aqueous phase was removed. The resulting organic phase was cooled from 80°C to 10°C. Thereafter, filtration was performed using a centrifuge (3000 rpm for 10 minutes) to obtain wet bisphenol C. Using an evaporator equipped with an oil bath, 179 g of white bisphenol C (VII) was obtained by distilling off the low-boiling components under reduced pressure at an oil bath temperature of 100°C.

The resulting bisphenol C(VII) had a sulfate ion of less than 1 mass ppm, a cresol sulfonic acid of less than 30 mass ppm, a sodium atom of less than 1 mass ppm, and a chlorine atom of less than 1 mass ppm.

[Color tone when melted]
20 g of the obtained bisphenol C (VII) was placed in a test tube for a spectrocolorimeter and placed in an aluminum block heater set at 175° C. to prepare a melt. Five minutes after confirming the complete melting, the melt was measured with a color difference meter and found to have a Hazen color number (APHA) of 15.

(Manufacture of polycarbonate resin)
100.00 g (0.39 mol) of bisphenol C (VII), 86.49 g (0.4 mol) of diphenyl carbonate and 400 mass ppm of 479 μL of cesium carbonate aqueous solution was added. The reaction vessel made of glass was evacuated to about 100 Pa, and then the operation of restoring the pressure to atmospheric pressure with nitrogen was repeated three times to replace the inside of the reaction vessel with nitrogen. After that, the reactor was immersed in an oil bath at 200° C. to dissolve the contents.

The rotation speed of the stirrer was set to 100 times per minute, and the pressure in the reaction vessel was increased to absolute pressure over 40 minutes while distilling off the phenol by-product of the oligomerization reaction of bisphenol C and diphenyl carbonate in the reaction vessel. The pressure was reduced from 101.3 kPa to 13.3 kPa. Subsequently, the pressure in the reactor was maintained at 13.3 kPa, and transesterification was carried out for 80 minutes while further distilling off phenol. Thereafter, the external temperature of the reaction vessel was raised to 250° C., and the internal pressure of the reaction vessel was reduced from 13.3 kPa to 399 Pa in absolute pressure over 40 minutes to remove distilled phenol out of the system.

Thereafter, the external temperature of the reaction vessel was raised to 280° C., the absolute pressure of the reaction vessel was reduced to 30 Pa, and a polycondensation reaction was carried out. The polycondensation reaction was terminated when the agitator in the reaction tank reached a predetermined stirring power.

Next, the pressure in the reactor was restored to 101.3 kPa in terms of absolute pressure with nitrogen, and then increased to 0.2 MPa in terms of gauge pressure.

After that, the strand was pelletized using a rotary cutter to obtain a polycarbonate resin in the form of pellets.

The polycarbonate resin had a viscosity-average molecular weight (Mv) of 24,200 and a terminal hydroxyl group (OH) concentration of 719 mass ppm. The pellet YI was 8.5.

Table 2 summarizes the procedures of the purification steps in Production Examples 12 and 13 and the amounts of ions contained in the obtained bisphenol C. As a result of Table 2, by using a production method having phase separation step 2C and phase separation step 2D, which removes the aqueous phase under acidic conditions, cresol sulfonic acid is less than 0.03 mass ppm and sodium atom is 1 mass ppm. It can be seen that it is possible to remove up to less than The phrases "less than 0.03 ppm by mass of cresol sulfonic acid" and "less than 1 ppm by mass of sodium atom" indicate that the amount of cresol sulfonic acid and sodium atom is below the lower limit of determination. Moreover, it can be seen that the ion component can also be efficiently removed by the method of Production Example 13.

ADVANTAGE OF THE INVENTION According to this invention, the bisphenol which has a favorable color tone can be manufactured. The produced bisphenol can be suitably used as a raw material for producing a polycarbonate resin.

Claims (7)

After mixing the bisphenol-containing solution and the first carbonate aqueous solution, phase separation is performed into a bisphenol-containing first organic phase and a carbonate-containing first aqueous phase, and the first aqueous phase is a first step of removing to obtain the first organic phase;
After mixing the first organic phase and the second aqueous carbonate solution, phase separation is performed into a second organic phase containing bisphenol and a second aqueous phase containing carbonate, and the second aqueous phase is a second step of removing to obtain the second organic phase;
and a third step of crystallizing the second organic phase to obtain bisphenol ,
Before the first step,
A bisphenol production step (1A) of producing a bisphenol by condensing a ketone or aldehyde and an aromatic alcohol in the presence of an acid catalyst to obtain a slurry in which the bisphenol is dispersed;
The slurry is heated and mixed with a basic aqueous solution in which any one selected from the group consisting of sodium hydroxide, potassium hydroxide and lithium hydroxide is dissolved in water to dissolve the bisphenol, and the mixture containing the bisphenol. a dissolving step (1B) for obtaining a liquid (m1);
After phase separation of the mixed liquid (m1) into an organic phase (o1) containing bisphenol and an aqueous phase (w1), the aqueous phase (w1) is removed, and the organic phase (o1) is and a phase separation step (1C) for obtaining a solution containing bisphenol. 2. The method for producing bisphenol according to claim 1 , wherein said acid catalyst is any one selected from the group consisting of sulfuric acid, hydrochloric acid and hydrogen chloride gas. After mixing the bisphenol-containing solution and the first carbonate aqueous solution, phase separation is performed into a bisphenol-containing first organic phase and a carbonate-containing first aqueous phase, and the first aqueous phase is a first step of removing to obtain the first organic phase;
After mixing the first organic phase and the second aqueous carbonate solution, phase separation is performed into a second organic phase containing bisphenol and a second aqueous phase containing carbonate, and the second aqueous phase is a second step of removing to obtain the second organic phase;
and a third step of crystallizing the second organic phase to obtain bisphenol ,
Before the first step,
A bisphenol production step (2A) of producing a bisphenol by condensing a ketone or aldehyde and an aromatic alcohol in the presence of a sulfuric acid catalyst to obtain a slurry in which the bisphenol is dispersed;
The slurry and a basic aqueous solution in which any one selected from the group consisting of sodium hydroxide, potassium hydroxide and lithium hydroxide is dissolved in water so that the mixed solution (m2) after mixing has a pH of 4 or less. a dissolving step (2B) of heating and mixing to dissolve the bisphenol to obtain a mixed liquid (m2) containing the bisphenol;
After phase separation of the mixed liquid (m2) into an organic phase (o2a) containing bisphenol and an aqueous phase (w2a), the aqueous phase (w2a) is removed to obtain the organic phase (o2a). a separation step (2C);
After mixing the organic phase (o2a) and water, phase separation is performed into an organic phase (o2b) containing bisphenol and an aqueous phase (w2b), the aqueous phase (w2b) is removed, and the organic phase (o2b ) and a phase separation step (2D) for obtaining the bisphenol-containing solution. The method for producing bisphenol according to any one of claims 1 to 3, wherein the bisphenol is a compound represented by the following general formula (1).

(In the formula,
R ¹ to R ⁴ each independently represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group or an aryl group;
at least one of R ¹ to R ⁴ is a halogen atom, an alkyl group, an alkoxy group or an aryl group;
R ⁵ and R ⁶ each independently represent a hydrogen atom, an alkyl group, an alkoxy group, or an aryl group, or R ⁵ and R ⁶ are combined together with the adjacent carbon atoms to form a cycloalkylidene group may be formed. ) The content of carbonate in the first carbonate aqueous solution is 0.0001 g or more and 0.1 g or less per 1 g of bisphenol in the solution containing bisphenol,
5. Any one of claims 1 to 4 , wherein the content of carbonate in said second carbonate aqueous solution is 0.0001 g or more and 0.1 g or less per 1 g of bisphenol in said first organic phase. The method for producing bisphenol described in . 6. The method for producing bisphenol according to any one of claims 1 to 5 , wherein the first carbonate aqueous solution and the second carbonate aqueous solution are sodium bicarbonate aqueous solutions. A step of obtaining bisphenol by the method for producing bisphenol according to any one of claims 1 to 6 ;
and a step of producing a polycarbonate resin using the obtained bisphenol.

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