阅读说明：本技术 一种双酚a的生产方法及装置 (Bisphenol A production method and device ) 是由 范洪明 彭斌 万荣波 周新 于 2019-08-23 设计创作，主要内容包括：本发明属于双酚A生产技术领域,具体涉及一种双酚A的生产方法及装置。所述双酚A的生产方法包括：步骤A：在酸催化剂作用下,过量的苯酚与丙酮发生缩合反应,得到含有双酚A的反应液；步骤B：所述反应液浓缩,得到浓缩液；步骤C：所述浓缩液进一步结晶,固液分离得到母液I,以及苯酚与4,4-双酚A的加合物滤饼；步骤D：所述母液I经异构化处理,分离,得到母液II,以及苯酚与4,4-双酚A的加合物滤饼；步骤E：所述母液II作为环氧树脂的生产原料与环氧化合物反应,生成副产多元酚环氧树脂。本发明所述生产方法能有效降低装置中杂质含量,减少甚至取消重质残渣的排放,降低原料苯酚、丙酮消耗,提升装置技术水平。(The invention belongs to the technical field of bisphenol A production, and particularly relates to a production method and a device of bisphenol A. The production method of the bisphenol A comprises the following steps: step A: under the action of an acid catalyst, carrying out condensation reaction on excessive phenol and acetone to obtain a reaction solution containing bisphenol A; and B: concentrating the reaction solution to obtain a concentrated solution; and C: further crystallizing the concentrated solution, and carrying out solid-liquid separation to obtain a mother solution I and an adduct filter cake of phenol and 4, 4-bisphenol A; step D: carrying out isomerization treatment and separation on the mother liquor I to obtain a mother liquor II and an adduct filter cake of phenol and 4, 4-bisphenol A; step E: the mother liquor II is used as a production raw material of epoxy resin to react with an epoxy compound to generate a byproduct of polyphenol epoxy resin. The production method can effectively reduce the content of impurities in the device, reduce and even cancel the discharge of heavy residues, reduce the consumption of phenol and acetone as raw materials, and improve the technical level of the device.)

1. A process for producing bisphenol a, comprising:

step A: in the presence of an acid catalyst, carrying out condensation reaction on excessive phenol and acetone to obtain a reaction mixed solution containing bisphenol A;

and B: concentrating the reaction mixed solution obtained in the step A to obtain a concentrated solution;

and C: crystallizing the concentrated solution obtained in the step B, and then carrying out solid-liquid separation to obtain a solid component which is an adduct containing 4, 4-bisphenol A and phenol, and further separating and removing phenol to obtain bisphenol A; the liquid component is mother liquid I;

step D: c, carrying out isomerization treatment on the mother liquor I obtained in the step C, continuously separating and respectively obtaining an adduct filter cake of phenol and 4, 4-bisphenol A and a mother liquor II again;

step E: and D, reacting the mother liquor II obtained in the step D with an epoxy compound to obtain the byproduct of the polyphenol epoxy resin.

2. The production method according to claim 1, wherein the content of phenol in the mother liquor II obtained in step C is controlled to be not more than 7 wt%, preferably less than 6 wt%, more preferably less than 4 wt%;

preferably, when the content of phenol in the mother liquor II is higher than 7 wt%, phenol is removed by concentration.

3. The production method according to claim 1 or 2, wherein in the step D, the isomerization treatment is: isomerizing the mother liquor I to obtain a mixed solution containing 11.3-13 wt% of 4, 4-bisphenol A, 1.9-2.2 wt% of 2, 4-bisphenol A isomer, phenol and other impurities;

preferably, the isomerization is carried out under the action of a catalytic cation exchange resin.

4. The production method according to any one of claims 1 to 3, wherein the reaction in step E specifically comprises: in the presence of a phase transfer catalyst quaternary ammonium salt, the mother liquor II reacts with an epoxy compound to obtain an etherification product, and then reacts with alkali to obtain a by-product polyphenol epoxy resin.

5. The production method according to claim 4, wherein the quaternary ammonium salt of the phase transfer catalyst is benzyltriethylammonium chloride;

and/or the epoxy compound is one or two of epichlorohydrin and beta-methyl-epichlorohydrin;

and/or the base is provided as an aqueous solution of one or more of sodium hydroxide, calcium hydroxide or potassium hydroxide, preferably an aqueous sodium hydroxide solution.

6. The production method according to any one of claims 1 to 5, further comprising step F: and D, carrying out catalytic decomposition treatment on part of the mother liquor II obtained in the step D, recovering phenol and/or 4-isopropenylphenol generated after decomposition, and discharging heavy residues generated by decomposition.

7. The production method according to claim 6, characterized in that the decomposition comprises in particular: catalytically decomposing the polyphenol in the mother liquor II into recoverable phenol and 4-isopropenylphenol under the conditions of catalytic alkali and high temperature;

preferably, the catalytic base is selected from NaOH and NaHCO₃、NaH₂PO₄One or more than one mixture.

8. The production method according to claim 6 or 7, wherein the phenol recovered in the step F is returned to the step A for recycling, or the phenol and 4-isopropenylphenol are subjected to rearrangement reaction to produce and recover 4, 4-bisphenol A.

9. A production apparatus for carrying out the method of any one of claims 1 to 8, comprising: the device comprises a reaction unit, a concentration unit, a crystallization unit, a solid-liquid separation unit, an isomerization unit, a mother liquor evaporation unit and an epoxy resin production unit which are connected in sequence; the isomerization unit comprises isomerization reaction equipment, concentration equipment, crystallization equipment and solid-liquid separation equipment which are connected in sequence.

10. The production plant according to claim 9, characterized in that it further comprises a decomposition unit, a heavy residue removal unit and a raw material recovery unit connected to the decomposition unit.

Technical Field

The invention relates to the technical field of bisphenol A production, in particular to a production method and a device of bisphenol A.

Background

Bisphenol a is an important compound as a raw material for engineering plastics such as polycarbonate resins and polyarylate resins, epoxy resins, and the like, and the demand thereof tends to increase in recent years. As a raw material for producing a high-quality resin, high-quality bisphenol a is required.

For example, CN104379546A discloses a method for producing bisphenol a (whose flow chart is shown in fig. 2), which comprises the following steps (a) to (F):

step (A): generating BPA in a reactor for condensation reaction of excessive phenol and acetone in the presence of an acid catalyst to obtain a reaction mixed solution containing BPA;

a step (B): dehydrating and concentrating the reaction mixed solution to obtain a dehydrated concentrated solution;

step (C): crystallizing the dehydrated concentrated solution, and then carrying out solid-liquid separation to separate the dehydrated concentrated solution into a solid component (adduct filter cake) and a mother solution I;

a step (D): at least one part of the mother liquor I existing in the system is subjected to isomerization treatment;

step (E): concentrating, crystallizing and carrying out solid-liquid separation on the isomerized solution to obtain a filter cake of phenol and 4, 4-bisphenol A adduct and mother liquor II;

a step (F): subjecting the mother liquor obtained in the step (E) to phenol recovery treatment, and subjecting at least a part of the mother liquor present in the system among the mother liquor after phenol recovery treatment to alkali decomposition treatment to decompose bisphenol a, 2, 4' -bisphenol a and triphenol present in the mother liquor; and (b) recovering phenol and/or p-isopropenylphenol, synthesizing bisphenol A from the recovered phenol and/or p-isopropenylphenol by a rearrangement reaction, and supplying the bisphenol A to the reactor in the step (A).

However, in the actual application of the method described in CN104379546A, the method still has the defects of many impurities in the device, large discharge amount of heavy residue, high energy consumption of alkali decomposition operation, and the like; in particular, when heavy residues are discharged, there is a loss of usable substances, which leads to an increase in consumption of phenol and acetone as raw materials and an increase in energy cost.

The invention aims to provide a preparation method of bisphenol A, which effectively reduces the content of impurities such as 2, 4-bisphenol A and the like in a device, greatly reduces the amount of impurities returned to a reaction unit, and reduces or even eliminates the discharge of heavy residues. The method can remarkably reduce the consumption of the raw materials of phenol and acetone and improve the technical level of the device.

Disclosure of Invention

In order to solve the technical problems, the invention provides a bisphenol A production method and a device, which can effectively reduce the content of impurities such as 2, 4-bisphenol A and the like in the device, greatly reduce the amount of impurities returned to a reaction unit, and reduce or even eliminate the discharge of heavy residues.

The production method comprises the following steps:

step A: in the presence of an acid catalyst, carrying out condensation reaction on excessive phenol and acetone to obtain a reaction mixed solution containing bisphenol A;

and B: concentrating the reaction mixed solution obtained in the step A to obtain a concentrated solution;

and C: crystallizing the concentrated solution obtained in the step B, and then carrying out solid-liquid separation to obtain a solid component which is an adduct containing 4, 4-bisphenol A and phenol, and further separating and removing phenol to obtain bisphenol A; the liquid component is mother liquid I;

step D: c, carrying out isomerization treatment on the mother liquor I obtained in the step C, continuously separating to obtain an adduct filter cake of phenol and 4, 4-bisphenol A and a mother liquor II respectively;

step E: and D, reacting the mother liquor II obtained in the step D with an epoxy compound to obtain the byproduct of the polyphenol epoxy resin.

The above steps are further explained below, and in step a, the synthesis of bisphenol a comprises the following reactions: phenol reacts with acetone to generate bisphenol A and also generate byproduct polyphenol impurities such as 2, 4-bisphenol A, triphenol, tetraphenol, chroman and the like.

And the step B aims to concentrate the reaction product in the step A, and materials such as water with low boiling point, acetone and the like are removed in the concentration process. Wherein, the acetone can be recovered, and the recovered acetone can be returned to the step A or used for other purposes.

In step C, the crystallization method may be selected from crystallization processes conventional in the art, such as suspension crystallization, falling film crystallization, vacuum crystallization, static crystallization, evaporative crystallization, and the like, or a combination of two or more crystallization methods. And (3) carrying out solid-liquid separation on the crystallized product to obtain a solid component containing the adduct of bisphenol A and phenol and a mother liquor I. Common methods for the solid-liquid separation step include vacuum filtration, centrifugal separation and the like; meanwhile, in the operation, the purity of the phenol and 4, 4-bisphenol A adduct filter cake can be further improved and the impurity content can be reduced by the washing operation of the washing liquid (phenol or the washing operation of the phenol and the adduct filter cake obtained by the first-stage solid-liquid separation by adopting the mother liquid obtained by the first-stage crystallization and the solid-liquid separation and the washing liquid obtained by the last-stage solid-liquid separation). Alternatively, phenol may be recovered when the solid component is removed, and the recovered phenol may be returned to step a or otherwise utilized.

The application researchers found that the impurities (byproduct polyphenol impurities) in the production process of bisphenol A can be used as raw materials to prepare polyphenol epoxy resin, waste materials are changed into wealth, the discharge of heavy residues can be reduced or cancelled, energy consumption is reduced, the obtained mother liquor is subjected to isomerization treatment before the preparation of the polyphenol epoxy resin, the yield of bisphenol A can be further improved, and the steps D and E are further arranged.

Preferably, said mother liquor II obtained by D has a phenol content of less than 7 wt%, preferably less than 6 wt%, more preferably less than 4 wt%;

as a preferred mode of operation, when the content of phenol in the mother liquor II is higher than 7% by weight, phenol is removed by concentration.

Alternatively, the phenol removed in this step can be recovered and the recovered phenol can be returned to step A or otherwise utilized.

Preferably, in the step D, the isomerization treatment is: the mother liquor I is isomerized to obtain a mixed solution containing 11.3 to 13 weight percent of 4, 4-bisphenol A, 1.9 to 2.2 weight percent of 2, 4-bisphenol A isomer, phenol and other impurities.

In the step D, the mother liquor I mainly comprises the following components: 9.8-10 wt% of 4, 4-bisphenol A, 3.3-3.5 wt% of 2, 4-bisphenol A isomer, phenol and other polyhydric phenol impurities.

As a preferred mode of operation, the isomerization is carried out under the action of a catalytic cation exchange resin.

As a preferable mode of operation, the isomerized compound is further concentrated to obtain a mixed solution containing 4, 4-bisphenol A25-26 wt%, 2, 4-bisphenol A isomer 4.2-4,4 wt%, phenol and other impurities.

As a preferable mode of operation, the concentrated solution is further crystallized, 4, 4-bisphenol A is crystallized by forming an adduct with phenol, and the filtrate cake (or the residue) is washed with a phenol solution by solid-liquid separation to obtain a phenol-4, 4-bisphenol A adduct filtrate cake and a mother liquor II mainly containing polyhydric phenol as a by-product.

Preferably, the reaction in step E specifically comprises: in the presence of a phase transfer catalyst quaternary ammonium salt, the mother liquor II reacts with an epoxy compound to obtain an etherification product, and then reacts with alkali to obtain the epoxy resin.

Preferably, the quaternary ammonium salt of the phase transfer catalyst is benzyltriethylammonium chloride;

preferably, the epoxy compound is epichlorohydrin or beta-methyl-epichlorohydrin;

preferably, the base is an aqueous sodium hydroxide solution.

Preferably, the step D further comprises the steps of washing the obtained crude epoxy resin with water, refining, and removing the solvent to obtain the finished epoxy resin.

If necessary, the process for producing bisphenol A further comprises a step F of subjecting a part of mother liquor II obtained in step D to catalytic decomposition treatment, recovering phenol and/or 4-isopropenylphenol obtained after the decomposition, and discharging a heavy residue produced by the decomposition.

And (3) under the condition that the byproduct polyphenol cannot be completely digested in the epoxy step, transferring the concentrated mother liquor II to a conventional catalytic cracking treatment step, and recovering effective components. The generation and discharge of solid waste, especially heavy residue, are effectively reduced.

The heavy residue typically includes heavy compounds such as chromans that are converted to non-volatile.

Preferably, the decomposing specifically includes: catalytically decomposing the polyphenol in the mother liquor II into recoverable phenol and 4-isopropenylphenol under the conditions of catalytic alkali and high temperature;

preferably, the catalytic base is selected from NaOH and NaHCO₃、NaH₂PO₄One or more than one mixture.

Preferably, the recovered phenol is returned to step A, or the phenol and 4-isopropenylphenol are subjected to a rearrangement reaction to produce 4, 4-bisphenol A, and 4, 4-bisphenol A is recovered.

Preferably, the catalyst for the rearrangement reaction is a cation exchange resin catalyst;

preferably, the cation exchange resin catalyst is prepared by the following method: styrene and divinyl benzene are adopted for crosslinking, and sulfonation reaction is carried out by adding sulfuric acid to prepare the belt-SO₃A base resin of H functional groups; modifying with promoter to obtain partial-SO₃Modifying the H functional group into sulfydryl to obtain the product containing-SO₃H and mercapto bifunctional catalyst.

The accelerator is preferably mercaptoethylamine (mercaptoalkylamines).

The invention also provides a bisphenol A production device for realizing the method, which comprises the following steps: the device comprises a reaction unit, a concentration unit, a crystallization unit, a solid-liquid separation unit, an isomerization unit, a mother liquor evaporation unit and an epoxy resin production unit which are connected in sequence; the isomerization unit comprises isomerization reaction equipment, concentration equipment, crystallization equipment and solid-liquid separation equipment which are connected in sequence.

Optionally, the production plant further comprises a decomposition unit, a heavy residue removal unit, and a feedstock recovery unit connected to the decomposition unit.

The invention has the following beneficial effects:

in the bisphenol A production process of the prior art, as described in CN104379546A, heavy residues are generated, and the discharge amount of the heavy residues reflects the material and energy loss of the process. By adopting the method, the mother liquor II is used as a production raw material for producing the byproduct polyhydric phenol epoxy resin, so that the generation of heavy residues in a decomposition process in a bisphenol A process is eliminated or at least greatly reduced, and the method has great benefits for environmental protection and reduction of energy consumption. In addition, the isomerization process reduces the generation of 2, 4-bisphenol A by-products, thereby reducing the consumption (synergy) of the raw materials of phenol and acetone, reducing the manufacturing cost of products and improving the technical level of devices.

Through calculation, the discharge amount of the polyphenol is about 2955 tons/year, the unit consumption of the phenol is about 842.3kg/t, the unit consumption of the acetone is about 271.6kg/t, and the energy consumption of all aspects is huge; after the method is adopted, the content of the 2, 4-bisphenol A in the device is greatly reduced; meanwhile, the discharge of heavy residues can be completely cancelled or partially reduced, so that the consumption (synergy) of raw materials of phenol and acetone is reduced, the manufacturing cost of the product is reduced, the technical advantages of product manufacturing are reflected, and the technical level of the device is improved.

Drawings

FIG. 1 is a process flow diagram of the process for the production of bisphenol A of the present invention.

FIG. 2 is a process flow diagram of the preparation process of bisphenol A disclosed in CN 104379546A.

Detailed Description

The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.

Wherein:

BPA molecular structural formula:

2,4-BPA molecular structural formula:

c3 phenol having one of the following molecular structural formulas:

the triphenol is triphenol, and one of molecular structural formulas of the triphenol is

The tetraphenol is a quaternary phenol, one of molecular structural formulas of which

Molecular structural formula of chroman

Example 1

This example provides a process for producing bisphenol a, comprising:

step A: in the presence of an acid catalyst, carrying out condensation reaction on excessive phenol and acetone to generate bisphenol A, and obtaining reaction mixed liquid containing the bisphenol A;

and B: b, dehydrating and concentrating the reaction mixed solution obtained in the step A to obtain a dehydrated concentrated solution;

and C: crystallizing the dehydrated concentrated solution obtained in the step B, and then carrying out solid-liquid separation to separate the dehydrated concentrated solution into a solid component containing an adduct of bisphenol A and phenol and a mother solution I;

step D: feeding mother liquor I with the flow rate of 12t/h and containing 10wt percent of 4, 4-bisphenol A, 3.3 percent of 2, 4-bisphenol A isomer, phenol and other impurities into an isomerization reactor, and carrying out isomerization reaction to obtain bisphenol A solution with the flow rate of 12t/h and containing 11.3 percent of 4, 4-bisphenol A, 1.9 percent of 2, 4-bisphenol A isomer, phenol and other impurities;

sending the mixture into a concentration unit to remove phenol to obtain a mixed solution of 25 wt% of 4, 4-bisphenol A, 4.2 wt% of 2, 4-bisphenol A isomer, phenol and other impurities with the flow rate of 5.42 t/h;

crystallizing and cooling, sending the solid-liquid phase mixed solution containing the phenol-4, 4 bisphenol A adduct crystal into a solid-liquid separator for solid-liquid separation, and washing with 1.35t/h phenol liquid with 99.9 wt% of phenol to obtain a filter cake and mother liquor II;

step E: mother liquor II (the flow rate is 5.08t/h, and contains 10 wt% of 4, 4-bisphenol A, 4.15% of 2, 4-bisphenol A isomer, phenol and other impurities, etc.) obtained from solid-liquid separation is fed into a phenol evaporation unit in the bisphenol A production process, and after dephenolization, a mixed solution with the flow rate of 1.19t/h, 5% of phenol, 42.6% of 4, 4-bisphenol A, 17.68% of 2, 4-bisphenol A isomer and other mixed solutions is obtained;

and (3) completely sending the obtained mixed solution into an epoxy resin production line, dissolving the mixed solution into excessive epoxy chloropropane, adding a phase transfer catalyst, heating to about 100 ℃ for etherification reaction, cooling to about 55 ℃, and dropwise adding a 48% NaOH aqueous solution for ring-closure reaction. And after the reaction is finished, recovering excessive epichlorohydrin to obtain crude epoxy resin, adding a toluene solvent and water to perform refining desalting, and finally removing the solvent to obtain the epoxy resin finished product.

By calculation, approximately 1.35 tons of epoxy resin can be produced when 1 ton of mixed liquid is consumed. 12852 tons of epoxy resin are produced annually (1.35 tons of epoxy resin are produced according to 1 ton of mixed solution, and the annual production time is 8000 hours).

And D, heating and melting the filter cake obtained in the step D to obtain a bisphenol A solution with the flow rate of 1.69t/h, the content of 50 wt% of 4, 4-bisphenol A, 1 wt% of 2, 4-bisphenol A isomer and the balance of phenol and trace impurities, and returning the bisphenol A solution to a filter cake tank before a crystallization unit in the bisphenol A production process or after solid-liquid separation in the bisphenol A production process.

Example 2

The same production method as in example 1 was employed except that:

step E: the mother liquor II is sent into a phenol evaporation unit, and after dephenolization, a mixed solution with the flow rate of 1.19t/h, containing 5 wt% of phenol, 42.6 wt% of 4, 4-bisphenol A, 17.68 wt% of 2, 4-bisphenol A isomer and other components is obtained.

A part of the resulting mixed solution was fed into an epoxy resin production line at a flow rate of 0.6t/h, and the specific production method was as described in example 1.

6480 tons of epoxy resin are produced annually (calculated according to the annual production time of 8000 hours for 1.35 tons of epoxy resin produced by 1 ton of mixed solution).

The remaining mixed solution was subjected to catalytic decomposition treatment (i.e., step F) at a flow rate of 0.59t/h, and the method reduced emissions of 1650 tons of heavy residues every year.

Example 3

The same production method as in example 1 was employed except that:

step D: feeding mother liquor I with the flow rate of 14t/h and containing 4, 4-bisphenol A9.8wt%, 2, 4-bisphenol A isomer 3.5 wt%, phenol and other impurities into an isomerization reactor, and carrying out isomerization reaction to obtain bisphenol A solution with the flow rate of 14t/h and containing 4, 4-bisphenol A13 wt%, 2, 4-bisphenol A isomer 2.2 wt%, phenol and other impurities;

sending the mixture into a concentration unit to remove phenol to obtain a mixed solution of 26 wt% of 4, 4-bisphenol A, 4.4 wt% of 2, 4-bisphenol A isomer, phenol and other impurities with the flow rate of 7 t/h;

crystallizing and cooling, sending the solid-liquid phase mixed solution containing the phenol-4, 4 bisphenol A adduct crystal into a solid-liquid separator for separation, and washing with 1.94t/h phenol of 99.9 wt% to obtain a filter cake and a mother liquor II;

step E: mother liquor II (the flow rate of which is 6.51t/h, and contains 10 wt% of 4, 4-bisphenol A, 4.43 wt% of 2, 4-bisphenol A isomer, phenol and other impurities and the like) obtained by solid-liquid separation is sent into a phenol evaporation unit, and after dephenolization, a mixed solution of polyhydric phenols with the flow rate of 1.54t/h, containing 5 wt% of phenol, 4-bisphenol A42.28wt%, 2, 4-bisphenol A isomer 14.3 wt% and other ternary and quaternary phenols is obtained;

the obtained mixed solution is completely sent into an epoxy resin production line, and 16632 tons of epoxy resin can be produced annually (calculated according to the annual production time of 8000 hours for 1.35 tons of epoxy resin produced by 1 ton of mixed solution);

and D, heating and melting the filter cake obtained in the step D to obtain a bisphenol A solution with the flow rate of 2.43t/h, the content of 4, 4-bisphenol A of 48 wt%, the content of 2, 4-bisphenol A isomer of 0.8 wt% and the content of other phenol and trace impurities, and returning the bisphenol A solution to the front of a crystallization unit of the main process flow.

Example 4

An apparatus for carrying out the production of bisphenol A as described in examples 1-3 above (schematically shown in FIG. 1), comprising: the device comprises a reaction unit, a concentration unit (dehydration unit), a crystallization unit, a solid-liquid separation unit I, an isomerization unit, a mother liquor concentration unit and an epoxy resin production unit which are connected in sequence;

the isomerization unit also comprises isomerization reaction equipment, concentration and crystallization equipment and solid-liquid separation equipment II.

The production device also comprises a decomposition unit and a rearrangement unit connected with a discharge port pipeline of the decomposition unit; the feed inlet of the decomposition unit is connected with the discharge outlet pipeline of the mother liquor concentration unit, and the discharge outlet of the rearrangement unit is connected with the feed inlet pipeline of the reaction unit.

Although the invention has been described in detail hereinabove with respect to a general description and specific embodiments thereof, it will be apparent to those skilled in the art that modifications or improvements may be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.