TW201542509A - Method of producing a high purity bisphenol F - Google Patents

Abstract

This invention provides a method of producing a high purity bisphenol F, in which a distillation process is used to separate crude bisphenol F and/or crude novolac resin as the distillate to obtain the high purity bisphenol F, is characterized by using a vertical rotary thin film evaporator, wherein the evaporator used in the distillation process is provided externally with a heating mechanism, a liquid supply opening and a steam outlet are disposed on the top part, and a sludge outlet is disposed at the bottom part. The main body of the evaporator has a cylindrical evaporator body and an internal rotary body with a wing. The internal rotary body is disposed in the body and moves circumferentially on the inner wall of the evaporator body, wherein the internal rotary body with a wing has a groove-containing wiper-like member which is in direct contact with the heating evaporation surface of the inner circumference of the body girth and, in addition to the part that supports the groove-containing wiper-like member, there is a space used for steam passage. A condenser is disposed outside the thin film evaporator.

Description

Method for producing high-purity bisphenol F

The present invention relates to a process for producing high-purity bisphenol F which is capable of efficiently obtaining high-purity bisphenol F by distillation.

In general, the general bisphenol F is a bisphenol F containing 85 to 93% by weight of a dinuclear body, preferably containing about 90 to 93% by weight, and is used as a raw material for a low-viscosity epoxy resin. The general bisphenol F is obtained by reacting phenol and formaldehyde with a molar ratio (P/F) of 20 to 50 to obtain bisphenol F which is useful as a raw material of an epoxy resin. In this regard, the high-purity bisphenol F is a bisphenol F having more dinuclear than the general bisphenol F, and is used as a raw material for an epoxy resin for coatings. For example, an epoxy resin obtained from bisphenol F containing 95% by weight or more of a dinuclear body is used as a constituent component as compared with a coating material containing an epoxy resin obtained from bisphenol F containing 92% by weight of a dinuclear body as a constituent component. The coating is excellent in corrosion resistance and chemical resistance of the coating film. Further, in the method of producing a high molecular weight bifunctional epoxy resin from a bifunctional epoxy resin and a divalent phenol compound, the dinuclear purity of the divalent phenol compound must be 95% by weight or more, and if it is below the purity, An epoxy resin for insolubilization (gelation) in the production of a high molecular weight body cannot be obtained. The high-purity bisphenol F having a dinuclear content of 98% by weight or more by the reaction of phenol and formaldehyde can not be achieved even if the reaction molar ratio P/F is 100 or more, which is industrially impossible. Then, as a method for producing high-purity bisphenol F, a method has been proposed in which high-purity bisphenol F is obtained by two-stage or more multi-stage distillation, or a mixture mainly composed of a dinuclear body is recrystallized to obtain high purity. Degree bisphenol F. In addition, an evaporation apparatus in which a multi-stage distillation structure is provided inside the evaporator has been proposed (JP-A-3-238001). In addition, there is no particular example of a distillation apparatus used in the production method of the high-purity bisphenol F which obtains high-purity bisphenol F by distillation (JP-A-6-1-218183).

The present invention provides a method for producing high-purity bisphenol F which is stable in a high yield in single distillation, and a vertical rotary thin film evaporator for producing high-purity bisphenol F.

In order to obtain high-purity bisphenol F at a high yield by distillation recovery from crude bisphenol F and crude novolak resin as a dinuclear component, the present inventors have specified the most efficient distillation apparatus and found distillation conditions thereof. The present invention has been found to have a method for producing high-purity bisphenol F which has a small environmental load and is advantageous for cost reduction.

That is, in the method for producing high-purity bisphenol F of the present invention, crude bisphenol F and/or crude novolak resin are separated by a distillation step to obtain high-purity bisphenol F as a distillation component, wherein the coarse double The phenol F and/or the crude novolac resin are obtained by reacting phenol with formaldehyde in the presence of a catalyst, removing the acid catalyst, water, and unreacted phenol from the obtained reaction product, characterized in that vertical rotation is used. In a vertical thin film evaporator, the evaporator used in the distillation step has a heating mechanism on the outer surface, a liquid supply port and a vapor discharge port on the upper portion, and a residue discharge port on the lower portion, and the main body of the evaporator The portion has a cylindrical evaporator body and an inner rotating body with a wing disposed inside the body and moving circumferentially along an inner wall surface of the evaporator body, wherein the inner rotation of the wing The body has a grooved wiper-like member in direct contact with the heated evaporation surface of the inner peripheral surface of the body crotch portion, and in addition to the portion supporting the grooved wiper-like member , But also has a space with a vapor passage, a condenser disposed outside the thin-film evaporator.

In the above-described distillation step, it is preferable to continuously supply the evaporator having a pressure of 1 to 10 mmHg and a heat medium temperature of 250 to 320 ° C in accordance with a supply amount of 30 to ²⁰⁰ kg/h per 1 m ² of the heat transfer area of the evaporator. The crude bisphenol F or the crude novolac resin is obtained by continuously extracting the evaporation component and the bottom component from the evaporator to obtain high-purity bisphenol F.

Further, the above production method is a high-purity bisphenol F having a dinuclear content of 95% by area or more as measured by gel permeation chromatography (GPC).

Further, the vertical rotary thin film evaporator used in the above-described production method includes a heating mechanism on the outer surface of the evaporator used in the distillation step, a liquid supply port and a vapor discharge port on the upper portion, and a residue discharge port on the lower portion. The main body portion of the evaporator has a cylindrical evaporator body and a winged inner rotating body disposed inside the body and moving in the circumferential direction along the inner wall surface of the evaporator body, wherein The inner rotating body of the wing has a grooved wiper-like member that is in direct contact with the heated evaporation surface of the inner peripheral surface of the body flange portion, and has a vapor in addition to a portion supporting the grooved wiper-like member. The space for the passage, the condenser is disposed outside the thin film evaporator.

The production method of the present invention can obtain high-purity bisphenol F at a high yield, and overall, it is advantageous in terms of environmental load and reduction in cost.

1‧‧‧heating jacket

2‧‧‧ Main body

3‧‧‧Internal rotating body

4‧‧‧Electric motor

5‧‧‧Rotary axis

6‧‧‧Agitator wing

7‧‧‧Liquid supply port

8‧‧‧Evaporation component discharge

9‧‧‧ bottom of the tower

10‧‧‧ Residue discharge

11‧‧‧ wiper body

12‧‧‧Wiper body installation

13‧‧‧ Spring

Fig. 1 is a longitudinal sectional view showing an example of a thin film evaporator of the present invention.

Fig. 2 is a longitudinal sectional view showing another example of the thin film evaporator of the present invention.

Fig. 3 is a schematic view showing an example of a wiper body attached to the inner rotating body of the wing of Fig. 1.

Fig. 4 is a schematic view showing an example of a wiper body attached to the inner rotating body of the wing of Fig. 2;

Embodiments of the present invention will be described in detail below.

The high-purity bisphenol F of the present invention is 95% by weight or more, preferably 98% by weight or more, and more preferably 99% by weight or more as the dinuclear body of the formula (1). Further, the crude bisphenol F and the general bisphenol F supplied to the distillation basically have the general formula (1) as a main component, and contain 7 to 15% by weight of the general formula (2) as an impurity to lower the raw material phenol, the reaction catalyst or the reaction. By-products to an almost negligible extent.

Therefore, the process of obtaining highly purified bisphenol F by distillation is merely an act of separating the trinuclear component of the general formula (2) from the general bisphenol F. Since the vapor pressure of the general formula (1) and the general formula (2) is greatly different and does not azeotrope, sufficient separation can be performed even by performing so-called single distillation. However, it has the necessary separation ability in the existing distiller. Further, in order to achieve distillation at a low temperature, it is necessary to have a low vacuum condition or more.

In addition, there are various types in the vertical rotary thin film evaporator, such as a type in which the condenser is internally or externally disposed, a type in which the agitating blade has a wiper body or a wiper body, and a void ratio in the inner rotating portion. Many types, types of stirring wing tilt settings, etc.

In the present invention, a vertical rotary thin film evaporator in which high-purity bisphenol F is obtained by a single distillation with sufficient separation is a type in which a condenser is provided outside, and a type of wiper body is attached to the stirring blade, and the inside is The rotating body has a high void ratio.

In the present invention, an external condenser is a necessary condition. In the case of the internal condenser type, even if a mist separator is provided, the general bisphenol F, crude bisphenol F or crude novolac resin (hereinafter referred to as a supply liquid) supplied to the distillation step is accompanied by a large amount of droplets in the distillation component. As a result, the distilled component could not be made into high-purity bisphenol F. Although it is also possible to improve the distillation conditions to reduce the amount of droplets, in this case, the supply rate of the supply liquid supplied to the evaporator is extremely slowed down, and the productivity is deteriorated, resulting in a comprehensive cost. The main reason for the rise.

Further, in the external condenser type, although the classification ratio is set and the distillation is performed more finely, it is not necessary in the distillation of bisphenol F, and generally it is an excessive quality, which causes an increase in cost.

Further, it is necessary for the inner rotating body to have a wiper body, and it is preferably a grooved wiper body. Although the wiper body is attached in an arbitrary manner, it is necessary to make the wiper body adhere to the inner wall surface of the cylinder. Therefore, it is more preferably a movable type with a spring or a movable type by a centrifugal force than a fixed wiper body. In the case of the fixed wiper body, the distance between the inner wall surface of the cylinder and the wiper body needs to be 1 mm or less. However, if the wiper body and the inner wall surface of the cylinder are grounded, the wiper body is reduced, which is not preferable. Further, the grooved wiper body is preferable because it can quickly thin the supply liquid and uniformize the heating portion.

Further, the material of the wiper body is preferably a material that does not damage the inner wall surface of the thin film evaporator, and more preferably a mixed carbon or a carbon that can be used even when the resin or the metal is vacuum-impregnated with carbon to increase the mechanical strength. A fluororesin or the like which is highly corrosive is more preferably a mixed carbon which is excellent in long-term shape stability and can be used even at a high temperature.

Further, the inner rotating body may be of a type in which a rotating blade is attached to the rotating shaft, or may be a cylindrical skeleton type. However, the void ratio when the inner rotating body is regarded as a cylinder is preferably 70% by volume or more, and more preferably 85. More than % capacity. The larger the void ratio of the inner rotating body, the easier the outflow of the distilled component is, which is preferable. On the other hand, the strength of the inner rotating body is also likely to be lowered, and from the balance of the two, the void ratio is preferably about 85 vol%.

Further, since the upper portion of the inner rotating body is a passage for the evaporation component to the evaporation component discharge port, it is preferable to maintain a sufficient strength to maintain the flow, and to have a hole for passage or a lattice shape.

1 and 3 show an example of a rotating body 3 in which four agitating blades 6 are attached to a rotating shaft 5, and is an example of a structure in which a wiper body 11 is attached to all ends or a part of the stirring blade, and a heating clamp is attached. The inner wall of the sleeve 1 is in close contact with the wiper body by a spring. The number of the stirring wings does not need to be four pieces, and may be arbitrarily 3 to 12 pieces depending on the size. In addition, the arrangement of the wiper body does not need to be on the entire end face of the agitating blade. 2 and 4 show an example of a cylindrical rotating body in which the upper and lower discs are connected by four columns, and the number of the columns does not need to be four, and may be arbitrarily 3 to 24 depending on the size. The column is not only used to connect the top and bottom, but also to set the wiper body. This example is an example of a structure in which a wiper body is provided inside a grooved column, and the wiper body is adhered to the inner wall of the heating jacket by centrifugal force. In the case where the adhesion is insufficient, a forced contact can be performed using a spring or the like. In addition, in order to make the upper part a passage for the evaporation component, Since the lower portion eliminates the supply of the supply liquid, it is necessary to provide a hole as shown in FIG. Moreover, if there is strength, it may be a perforated disc or a lattice shape.

Although FIGS. 1 to 2 show longitudinal cross-sectional schematic views of an example of the vertical rotary thin film evaporator of the present invention, the present invention is not limited to this example as long as the present invention does not exceed the gist. This device is a thin film evaporator having a cylindrical main body portion 2 having a heating jacket 1 on the outside, and has an internal rotating body 3 and a motor 4 that rotates. The inner rotating body may be of a type in which the agitating blades 6 are attached to the rotating shaft 5. The wiper body 11 attached to the inner rotating body rotates in contact with the wall surface of the main body portion. The liquid to be treated supplied from the liquid supply port 7 in the upper portion of the thin film evaporator is pressed and developed in a film shape along the inner wall of the main body portion by the rotating wiper body, and flows down according to the gravity. In the course of this flow, the component of the above formula (1) in the supply liquid evaporates by the heat from the heating jacket. The evaporated component of the formula (1) is recirculated out of the system from the evaporation component discharge port 8 located at the upper portion of the thin film evaporator, and most of the evaporated component is removed, and the evaporation residue having poor fluidity is guided to the bottom of the column. 9. It is discharged from the residue discharge port 10 located at the lower portion of the thin film evaporator. Since the component of the formula (1) evaporates during the flow down process, the void ratio of the inner rotating body is important, and it is important to set the structure which does not affect evaporation.

Further, the installation position of the external condenser is preferably a region where the vapor outlet is small and distant. If it is close to the vapor outlet, it is less likely to be affected by the droplets of the supply liquid as in the internal condenser, which is not preferable. In the design, when the external condenser is placed near the vapor outlet, it is necessary to provide a mist separator between the two. In order to prevent the occurrence of droplets, it is preferable that the installation area of the external condenser is about twice the length of the evaporator, and it is preferable that the diameter of the piping connected to the external condenser is 1/2 to 3/5 of the inside of the evaporator.

The distillation condition for obtaining high-purity bisphenol F according to the present invention is preferably 30 to ²⁰⁰ kg/h per 1 m ² of the evaporator in which the pressure is 1 to 10 mmHg and the heat medium temperature is 250 to 320 °C. The supply amount is continuously supplied to the supply liquid.

The pressure of the distillation conditions is more preferably 3 to 8 mmHg, still more preferably 4 to 7 mmHg, and most preferably 5 to 6 mmHg. When the pressure is low, if the temperature of the heat medium is high, the amount of evaporation will increase, and the accompanying supply liquid may be accompanied by droplets, which is not preferable. When the temperature of the heat medium is lowered according to the amount of evaporation, the amount of evaporation of the above-mentioned general formula (1) as a target product is reduced as compared with the case where the temperature of the heat medium is high and the pressure is high, which is not preferable.

The heat medium temperature is more preferably 260 to 300 ° C, still more preferably 270 to 290 ° C. In the case of a low temperature, particularly if it is lower than 250 ° C, the amount of evaporation cannot be maintained without greatly reducing the pressure, and in this case, the amount of the accompanying droplets is increased, and as a result, high-purity bisphenol F may not be obtained. In addition, if it is high temperature, decomposition and coloring of the supply liquid may occur, and the physical properties of the high-purity bisphenol F as a target may be deteriorated.

More preferably, the amount of the supply liquid supplied to the evaporator is 30 to 150 kg/h per 1 m ² of the evaporator, more preferably 50 to 120 kg/h, and most preferably 70 to 100 kg/h. When the amount of supply is large, the separation of the above formula (1) and the feed liquid as a target product is insufficient, and high-purity bisphenol F may not be obtained.

[Examples]

Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited thereto. In the examples, "parts" means parts by mass, and "%"' means % by mass unless otherwise specified. Further, the purity of the dinuclear bodies in the examples and the comparative examples was measured by the following method.

Dinuclear purity: The area % measured by GPC was determined. The measurement conditions of GPC are as follows.

Column: G4000 _HXL + G2500 _HXL + G2000 _HXL X 2 (Tosoh Corporation)

Column temperature: 40 degrees

Eluent: tetrahydrofuran

Flow rate: 1mL/min

Sample concentration: 0.1g/10mL tetrahydrofuran

Detector: RI detection

Example 1

Using the thin film evaporator of the present invention (heating conductive surface 0.21 m ² , outer condenser conductive surface 1.3 m ² , wiper body with spring fluororesin), a heat medium flowing through 280 ° C in the heating jacket is externally The heated water of 120 ° C was passed through the condenser, and the number of revolutions of the rotor was set to 250 rpm. The film evaporator was continuously supplied at 21 kg/h for 1 hour in a state of operation at a vacuum of 5 to 6 mmHg, and the evaporation component and the bottom component were continuously discharged. , bisphenol F and novolak resin were obtained, respectively.

Example 2

Using the thin film evaporator of the present invention (heating conductive surface 0.21 m ² , external condenser conductive surface 1.3 m ² , wiper body with spring fluororesin), a heat medium flowing through 260 ° C in the heating jacket is externally The heated water of 120 ° C was passed through the condenser, and the number of revolutions of the rotor was set to 250 rpm. The film evaporator was continuously supplied at 8 kg/h for 1 hour in a state of operation at a vacuum of 3 to 4 mmHg, and the evaporation component and the bottom component were continuously discharged. , bisphenol F and novolak resin were obtained, respectively.

Example 3

Using the thin film evaporator of the present invention (heating conductive surface 0.21 m ² , external condenser conductive surface 1.3 m ² , wiper body with spring fluororesin), a heat medium flowing through 300 ° C in the heating jacket is externally The heated water of 120 ° C was passed through the condenser, and the number of revolutions of the rotor was set to 250 rpm. The film evaporator was continuously supplied at 30 kg/h for 1 hour in a state of operation at a vacuum of 6 to 7 mmHg, and the evaporation component and the bottom component were continuously discharged. , bisphenol F and novolak resin were obtained, respectively.

Comparative example 1

Using a thin film evaporator different from the present invention (heating conductive surface 0.40 m ² , inner condenser conductive surface 1.3 m ² , wiper body with spring fluororesin), a heat medium flowing through 280 ° C in the heating jacket is used. The heating water of 120 ° C was passed through the external condenser, the number of revolutions of the rotor was set to 250 rpm, and the film evaporator was continuously supplied at 40 kg/h for 1 hour in a state of operation at a vacuum of 5 to 6 mmHg, and the evaporation component and the tower were continuously discharged. The bottom component gives bisphenol F and novolak resin, respectively.

Comparative example 2

Using a thin film evaporator different from the present invention (heating conduction surface 0.30 m ² , external condenser conduction surface 1.3 m ² , no wiper body, 1.5 mm gap between the main body and the inner rotating body), flowing through the heating jacket through 280 ° C The heat medium was passed through a heated water of 120 ° C in an external condenser, and the number of revolutions of the rotor was set to 1470 rpm, and the film evaporator was continuously supplied at 30 kg/h for 1 hour in a state of operation at a vacuum of 5 to 6 mmHg, and was continuously discharged. The component and the bottom component were evaporated to obtain bisphenol F and a novolak resin, respectively.

The binuclear purities of bisphenol F obtained in Examples 1 to 3 and Comparative Examples 1 and 2 are shown in Table 1.

In the thin film evaporator of the present invention, that is, a vertical rotary thin film evaporator with a winged inner rotating body that moves in the circumferential direction along the inner wall surface of the evaporator body disposed inside, the inner rotation of the wing is provided The body has a grooved wiper-like member that is in direct contact with the heated evaporation surface of the inner peripheral surface of the body portion, and has a space for the vapor passage other than the portion supporting the grooved wiper-like member, condensing The apparatus is disposed outside the thin film evaporator, and if it is the above thin film evaporator, high purity bisphenol F can be obtained by single distillation even if the distillation conditions are changed. On the other hand, in the comparative example using the thin film evaporator different from the present invention, the purity of the dinuclear body was low, and high-purity bisphenol F could not be obtained.

1‧‧‧heating jacket

2‧‧‧ Main body

3‧‧‧Internal rotating body

4‧‧‧Electric motor

5‧‧‧Rotary axis

6‧‧‧Agitator wing

7‧‧‧Liquid supply port

8‧‧‧Evaporation component discharge

9‧‧‧ bottom of the tower

10‧‧‧ Residue discharge

Claims (4)

A method for producing high-purity bisphenol F, which is obtained by separating a crude bisphenol F and/or a crude novolac resin by a distillation step to obtain a high-purity bisphenol F, wherein the crude bisphenol F and/or coarse A novolak resin is obtained by reacting phenol with formaldehyde in the presence of a catalyst, removing an acid catalyst, water, and unreacted phenol from the obtained reaction product, characterized in that a vertical rotary thin film evaporator is used, which In the vertical rotary thin film evaporator, the evaporator used in the distillation step has a heating mechanism on the outer surface, a liquid supply port and a vapor discharge port on the upper portion, and a residue discharge port on the lower portion, and the main body portion of the evaporator has a cylindrical shape. An evaporator body and an inner rotating body with a wing disposed inside the body and moving in a circumferential direction along an inner wall surface of the evaporator body, wherein the inner rotating body with the wing has a body and a body a grooved wiper-like member that is in direct contact with the heated evaporation surface of the inner peripheral surface, and has a portion other than the portion supporting the grooved wiper-like member A gas passage space, a condenser disposed outside the thin-film evaporator. The method for producing high-purity bisphenol F according to claim 1, wherein in the evaporation step, the evaporator is maintained at a pressure of 1 to 10 mmHg and a heat medium temperature of 250 to 320 °C. When the heat transfer area is supplied in an amount of 30 to ²⁰⁰ kg/h per 1 m ² , the crude bisphenol F or the crude novolac resin is continuously supplied, and the evaporation component and the bottom component are continuously taken out from the evaporator while being high. Purity bisphenol F. A high-purity bisphenol F obtained by the production method according to claim 1 or 2, wherein the dinuclear content measured by gel permeation chromatography is 95% by area or more. A vertical rotary thin film evaporator for producing high-purity bisphenol F, which is used in the production method according to claim 1 or 2, wherein the evaporator outside the evaporator has a heating mechanism The upper portion has a liquid supply port and a vapor discharge port, and the lower portion has a residue discharge port. The main body portion of the evaporator has a cylindrical evaporator body and a winged inner rotating body, and the inner rotating body is disposed inside the body And moving circumferentially along the inner wall surface of the evaporator body, wherein the inner rotating body with the wings has a grooved wiper-like member that is in direct contact with the heated evaporation surface of the inner peripheral surface of the body crotch portion, and In addition to the portion supporting the grooved wiper-like member, there is a space for the vapor passage, and the condenser is disposed outside the thin film evaporator.