JP4298438B2 - Method for preparing modified catalyst for production of bisphenol A - Google Patents

Description

  The present invention relates to a method for preparing a catalyst for use in the production of bisphenol A [2,2-bis (4-hydroxyphenyl) propane]. More specifically, the present invention is obtained by partially modifying a strongly acidic ion exchange resin with a sulfur-containing amine compound. The present invention relates to a method for preparing a modified catalyst for producing bisphenol A.

Bisphenol A is known to be an important compound as a raw material for engineering plastics such as polycarbonate resin and polyarylate resin, or epoxy resin, and in recent years its demand has been increasing.
In the production of bisphenol A, a strongly acidic ion exchange resin partially modified with a sulfur-containing amine compound is used as a catalyst. As a method for preparing such a catalyst, a sulfur-containing amine is used in a fixed bed reactor. A method is adopted in which compounds are added all at once to modify the sulfonic acid type ion exchange resin.
Usually, when a sulfur-containing amine compound is added all at once in a fixed bed reactor to modify a sulfonic acid type ion exchange resin, the sulfur-containing amine compound moves the sulfonic acid group in the resin which is a fixed bed by an acid (sulfonic acid). Adsorption to the group, elimination and transfer from the sulfonic acid group) At this time, the sulfur-containing amine compound moves from the inlet to the outlet of the fixed bed reactor, but the sulfonic acid type ion exchange resin is not uniformly modified by only one movement. That is, during the transfer of the sulfur-containing amine compound, the concentration of the sulfur-containing amine compound is high at the outlet of the fixed bed reactor (high denaturation rate with a modification rate of about 30 to 80%) and low at the inlet of the fixed bed reactor. Since the modification rate is a low modification rate of about 5 to 30%, there is a problem that the sulfonic acid ion exchange resin is not uniformly modified by only one movement.
The cation exchange resin fixed bed neutralized with a sulfur-containing amine compound is prepared by various methods. For example, a method for preparing an acidic cation exchange resin fixed bed in which an acidic cation exchange resin is neutralized with a sulfur-containing amine compound ( For example, see Patent Documents 1 to 4). Moreover, although the method (for example, refer patent document 5) which circulates the sulfur-containing amine compound aqueous solution which added hydrochloric acid in the resin fixed bed is disclosed, there exists a possibility that an installation may corrode if a large amount of hydrochloric acid is used.
Further, as a method for preparing a catalyst for producing bisphenols, a method of injecting a dilute solution of a sulfur-containing amine compound while stirring an ion exchange resin in a reaction vessel (see, for example, Patent Document 6), acidic cation exchange in a reactor A method in which an acidic cation exchange resin is uniformly neutralized by charging bubbles from the bottom of the reactor after charging or charging with an aqueous solution of a sulfur-containing amine compound (see, for example, Patent Document 7) Is disclosed. However, in the former case, a large-scale dilute solution storage facility is required, and because batch production is performed by impeller agitation, the ion exchange resin is damaged, and the ion exchange resin is refilled to form a fixed bed. Need. In the latter case, since the preparation is carried out at a pH of 6 or more, it is difficult to homogenize the sulfur-containing amine compound. As a result, there is a problem that the catalyst performance is lowered because it becomes a non-uniform modified catalyst.

Japanese Patent Application Laid-Open No. Hei 6-296871 JP 2001-286770 A JP-A-8-40961 JP 2001-288132 A Japanese Patent Laid-Open No. 53-14680 Japanese Patent Laid-Open No. 9-24279 JP 2000-254523 A

  The present invention has been made in view of the above circumstances, and provides a method for preparing a modified catalyst for producing bisphenol A, in which a strongly acidic ion exchange resin is not damaged, the strongly acidic ion exchange resin is uniformly modified, and has excellent catalytic performance. It is intended to provide.

As a result of intensive studies to solve the above problems, the present inventors filled a fixed bed reactor with a strongly acidic ion exchange resin and contained an acid aqueous solution and a concentration equivalent to the concentration in the acid aqueous solution. It has been found that the above object can be achieved by injecting a sulfuramine compound to modify a strongly acidic ion exchange resin. The present invention has been completed based on such findings.
That is, the present invention is a method for preparing a modified catalyst for producing bisphenol A, which is obtained by partially modifying a strongly acidic ion exchange resin with a sulfur-containing amine compound, and charging the fixed bed reactor with the strongly acidic ion exchange resin, An aqueous solution and a sulfur-containing amine compound having an equilibrium concentration in the aqueous acid solution are injected into this to provide a method for preparing a modified catalyst for producing bisphenol A, which modifies a strongly acidic ion exchange resin. is there.

  According to the present invention, a strongly acidic ion exchange resin is not damaged, the strongly acidic ion exchange resin is uniformly modified, the time for uniform modification is short, and a modified catalyst for producing bisphenol A having excellent catalytic performance is prepared. can do.

Examples of the strongly acidic ion exchange resin used in the present invention include sulfonated ion exchange resins such as sulfonated styrene-divinylbenzene copolymer, sulfonated crosslinked styrene polymer, phenol formaldehyde-sulfonic acid resin, and benzeneformaldehyde-sulfonic acid resin. It is done. The strongly acidic ion exchange resin is packed into a fixed bed reactor. Since the ion-exchange resin is directly packed in the fixed bed, the ion-exchange resin is not damaged in the ion-exchange resin modification step, and there is no transfer from the batch reactor or the modified catalyst preparation tank. It is advantageous.
In the present invention, the sulfur-containing amine compound used for modification of the strongly acidic ion exchange resin includes mercaptopyridines such as 3-mercaptopyridine, mercaptoalkylamines such as 2-mercaptoethylamine, and thiazolidines such as 2,2-dimethylthiazolidine. And aminothiophenols such as 4-aminothiophenol, and pyridine alkanethiols such as 4-pyridineethanethiol. Of these, 4-pyridineethanethiol, 2,2-dimethylthiazolidine and 2-mercaptoethylamine are preferred. These can be used individually by 1 type or in combination of 2 or more types.
The modification rate of the strongly acidic ion exchange resin with the sulfur-containing amine compound is usually about 5-45%, preferably 8-35%, more preferably 10-30%. By setting the upper limit of the modification rate to about 45%, the catalyst activity is not lowered, and by setting the lower limit to about 5%, the catalyst life is shortened or the catalyst activity and selectivity are lowered. There is nothing. Here, the “modification rate” of the strongly acidic ion exchange resin means the molar modification rate of the strongly acidic ion exchange group of the strongly acidic ion exchange resin by the sulfur-containing amine compound.

As the acid, an organic acid or an inorganic acid can be used. Examples of the organic acid include aromatic sulfonic acids such as benzenesulfonic acid, paratoluenesulfonic acid, and xylenesulfonic acid, alkylsulfonic acids such as methanesulfonic acid and ethanesulfonic acid, acetic acid, and formic acid. Of these, aromatic sulfonic acids are preferable, and paratoluenesulfonic acid is more preferable. Moreover, the acidic aqueous solution obtained by the water washing process of a sulfonic acid type ion exchange resin is also suitable. Examples of the inorganic acid include phosphoric acid, boric acid and sulfuric acid, and phosphoric acid is preferred. The use of aromatic sulfonic acids and phosphoric acid has the advantage that there is almost no corrosion of equipment.
The concentration of the acid aqueous solution is usually about 0.01 to 5% by mass, preferably 0.03 to 2% by mass when using strong acids such as aromatic sulfonic acids, alkylsulfonic acids and sulfuric acid. When using weak acids, such as acetic acid, formic acid, and phosphoric acid, it is about 0.01-8 mass% normally, Preferably it is 0.05-3 mass%. By setting the upper limit of the acid concentration to about 5% by mass in the case of a strong acid and about 8% by mass in the case of a weak acid, the concentration of the sulfur-containing amine compound (hereinafter referred to as “containing” "Equilibrium concentration of sulfur amine compound") is not increased, so that the amount of acid used and the loss of sulfur-containing amine compound are small, which is economically preferable. Further, by setting the lower limit of the acid concentration to about 0.01% by mass, the equilibrium concentration of the sulfur-containing amine compound does not become too low, so that the time required for modification does not become too long.
Here, the equilibrium concentration of the sulfur-containing amine compound in the acid aqueous solution is determined as follows. For example, an acid solution is added to a strongly acidic ion exchange resin swollen with water, and stirring and filtration are repeated, water is replaced with an acid solution, and then a 10% by mass aqueous solution of a sulfur-containing amine compound is stirred with the ion exchange resin. Add slowly. In addition, so far, it is catalyst preparation in a batch. Thereafter, a part of the aqueous solution is sampled and subjected to total nitrogen analysis, and the concentration of the sulfur-containing amine compound is determined from the total nitrogen concentration.

In the present invention, prior to denaturation of the strongly acidic ion exchange resin, it is preferable to replace the water contained in the fixed bed (strongly acidic ion exchange resin) of the fixed bed reactor with an acid aqueous solution. This is because the water-swelling type gel-type ion exchange resin that is usually used as a strongly acidic ion exchange resin contains about 50% by mass of water. By performing such substitution, the acid concentration can be kept constant when the acid aqueous solution flowing out from the outlet of the reactor is circulated and recycled.
The temperature for the catalyst preparation (modification of the strongly acidic ion exchange resin with the sulfur-containing amine compound) is usually about 0 to 120 ° C, preferably 20 to 100 ° C. When the upper limit of the catalyst preparation temperature is about 120 ° C., the ion exchange resin does not decompose, and when the lower limit is about 0 ° C., the problem that the acid aqueous solution is solidified does not occur.
The injection of the acid aqueous solution and the sulfur-containing amine compound is usually performed by injecting a preparation solution in which the sulfur-containing amine compound is dissolved in the acid aqueous solution. The amount of the aqueous solution injected is generally about 0.1 to 20 h ⁻¹ , preferably 0.2 to 10 h ⁻¹ , more preferably 0.4 to about LHSV (liquid space velocity) from the viewpoint of acid concentration and preparation time. 5h ^-1 . Moreover, the linear velocity of this preparation liquid is about 0.1-100 m / h normally, Preferably it is 0.2-50 m / h, More preferably, it is 0.5-20 m / h.

The time required for catalyst preparation is determined by the acid concentration and acid type in the acid aqueous solution, the equilibrium concentration of the sulfur-containing amine compound, the modification rate of the strongly acidic ion exchange resin with the sulfur-containing amine compound, LHSV, and the like. The amount of the sulfur-containing amine compound consumed in preparing the catalyst is determined by the modification rate. The concentration of the sulfur-containing amine compound injected into the fixed bed reactor is the equilibrium concentration of the sulfur-containing amine compound.
In catalyst preparation, a fixed amount of a preparation solution in which a sulfur-containing amine compound is dissolved in an acid aqueous solution is injected from the inlet of the fixed bed reactor, and the preparation solution that has passed through the strongly acidic ion exchange resin packed in this reactor is fixed. It flows out from the outlet of the bed reactor. There is a method of disposal of this preparation solution, or recycling and recycling, but there is a method of recycling by recycling because the amount of waste liquid becomes small and the amount of sulfur-containing amine compound and acid used is reduced. preferable. In the case of recycling, the concentration of the sulfur-containing amine compound in the preparation liquid flowing out from the outlet of the fixed bed reactor is measured, and an amount of the sulfur-containing amine compound is added so that the sulfur-containing amine compound has an equilibrium concentration. The concentration of the sulfur-containing amine compound can be determined by measuring the nitrogen concentration in the preparation solution containing the sulfur-containing amine compound and the acid. The measurement interval for the concentration of the sulfur-containing amine compound is generally determined every 2 to 20 hours because the total injection time is roughly determined by the equilibrium concentration of the sulfur-containing amine compound to be injected and the modification rate of the ion exchange resin. In addition, when circulating the preparation liquid containing a sulfur-containing amine compound and an acid, the injection amount (circulation amount) to a fixed bed reactor can be made into LHSV and linear velocity similar to the above.
In catalyst preparation, the flow of the preparation liquid containing the acid and the sulfur-containing amine compound in the fixed bed reactor may be either downflow or upflow. However, in the case of upflow, since the development (floating, flow, etc.) of the ion exchange resin increases as the amount of the preparation liquid injected increases, downflow is preferred in the present invention.

Using the modified catalyst prepared as described above, bisphenol A is produced using phenol and acetone as raw materials. Addition of the modified catalyst to the raw material in the fixed bed reactor can be performed under substantially the same conditions as the conditions (LHSV and linear velocity) when the catalyst was prepared. The ratio of phenol and acetone used is not particularly limited, but it is desirable that the amount of unreacted acetone is as small as possible from the viewpoint of ease of purification of bisphenol A to be produced and economic efficiency. It is advantageous to use in excess of the theoretical amount. Usually, about 3 to 30 mol, preferably 5 to 15 mol of phenol is used per mol of acetone. Moreover, reaction temperature is about 40-150 degreeC normally, Preferably it is the range of 60-110 degreeC.
The condensation reaction of phenol and acetone may be either a batch type or a continuous type. However, there is a fixed bed continuous reaction method in which phenol and acetone are continuously supplied to a reaction tower packed with a modified catalyst and reacted. preferable.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.
Example 1
As reactors, four reactors having an inner diameter of 10 mm and a length of 1200 mm are connected in series, and the outlet side and the inlet side are connected by piping, and the prepared liquid discharged from the reactor outlet is circulated to the inlet side. A reactor was used. This reactor was filled with 300 ml of a water-swelled sulfonic acid type cation exchange resin (manufactured by Mitsubishi Chemical Corporation, trade name: Diaion SK-104), and washed with 1500 ml of distilled water in a down flow. Subsequently, the water in the reactor and the piping was replaced with a 0.3 mass% phosphoric acid aqueous solution. A preparation solution in which 2,2-dimethylthiazolidine was added to a 0.3% by mass phosphoric acid aqueous solution so that the concentration of 2,2-dimethylthiazolidine was 117 ppm by mass was added to the reactor at 300 ml / h (LHSV = 1 h ⁻¹ , linear velocity = 3.8 m / h). The target modification rate with 2,2-dimethylthiazolidine was 23%, and the above prepared solution was continuously injected for 298 hours, and the above ion exchange resin was modified at 25 ° C. The prepared liquid that flowed out from the outlet of the fourth reactor was recycled by circulating it in the first reactor. At this time, the 2,2-dimethylthiazolidine content in the preparation liquid flowing out from the fourth reactor outlet was measured every 20 hours with a total nitrogen analyzer, and 2,2-dimethylthiazolidine was maintained in an amount of 117 mass ppm. Added.
After the injection of the preparation solution in which 2,2-dimethylthiazolidine was added to the phosphoric acid aqueous solution was completed, the modified catalyst was extracted from the reactor, and the phosphoric acid aqueous solution was removed with distilled water. The modified catalyst was dried, and the modification rate was measured by the following method. The results are shown in Table 1.

<Measurement of denaturation rate>
The acid equivalent was measured by a titration method using an aqueous sodium hydroxide solution, the neutralization rate was calculated based on the following formula, and this neutralization rate was taken as the modification rate.
Neutralization rate (%) = 100 × {1- [acid equivalent of modified resin (meq./g)/acid equivalent of unmodified resin (meq./g)]}

Example 2
In Example 1, a preparation liquid containing 440 mass ppm of 2,2-dimethylthiazolidine prepared by using a 1.0 mass% phosphoric acid aqueous solution instead of a 0.3 mass% phosphoric acid aqueous solution was continuously injected for 79 hours. A modified catalyst was obtained in the same manner as in Example 1 except that. Evaluation similar to Example 1 was performed about the obtained modified catalyst. The results are shown in Table 1.
Example 3
In Example 1, instead of 2,2-dimethylthiazolidine, a preparation containing 52 mass ppm of 2-mercaptoethylamine was used, the target modification rate was 15%, and this preparation was continuously injected for 280 hours. A modified catalyst was obtained in the same manner as in Example 1. Evaluation similar to Example 1 was performed about the obtained modified catalyst. The results are shown in Table 1.
Example 4
In Example 1, a preparation liquid containing 131 mass ppm of 2,2-dimethylthiazolidine prepared using a 0.3 mass% paratoluenesulfonic acid aqueous solution instead of a 0.3 mass% phosphoric acid aqueous solution for 266 hours continuously. A modified catalyst was obtained in the same manner as in Example 1 except that it was injected into the catalyst. Evaluation similar to Example 1 was performed about the obtained modified catalyst. The results are shown in Table 1.

Comparative Example 1
In Example 1, 10.1 g of the total amount of 2,2-dimethylthiazolidine used was injected in 0.5 hour, and 0.3 mass% phosphoric acid aqueous solution was recycled for the same time as in Example 1 A modified catalyst was obtained in the same manner as in Example 1. Evaluation similar to Example 1 was performed about the obtained modified catalyst. The results are shown in Table 1.
Comparative Example 2
In Example 2, a total amount of 2,2-dimethylthiazolidine used of 10.1 g was injected in 0.5 hours, and a 1.0 mass% phosphoric acid aqueous solution was recycled for the same time as in Example 2. A modified catalyst was obtained in the same manner as in Example 2. Evaluation similar to Example 1 was performed about the obtained modified catalyst. The results are shown in Table 1.
Comparative Example 3
In Example 3, 4.2 g of the total amount of 2,2-mereptethylamine used was injected in 0.5 hours, and 0.3 mass% phosphoric acid aqueous solution was recycled for the same time as in Example 1. A modified catalyst was obtained in the same manner as in Example 3. Evaluation similar to Example 1 was performed about the obtained modified catalyst. The results are shown in Table 1.
Comparative Example 4
In Example 4, 10.1 g of the total amount of 2,2-dimethylthiazolidine used was injected in 0.5 hour, and 0.3 mass% phosphoric acid aqueous solution was recycled and recycled for the same time as in Example 4. A modified catalyst was obtained in the same manner as in Example 4. Evaluation similar to Example 1 was performed about the obtained modified catalyst. The results are shown in Table 1.

Claims (13)

In a method for preparing a modified catalyst for producing bisphenol A, which is obtained by partially modifying a strongly acidic ion exchange resin with a sulfur-containing amine compound, a strongly acidic ion exchange resin is charged into a fixed bed reactor, and an acid aqueous solution is added thereto. A bisphenol A characterized by injecting a sulfur-containing amine compound in a concentration that is in equilibrium with the sulfur-containing amine compound in the strongly acidic ion-exchange resin having the desired modification rate in the acid aqueous solution to modify the strongly acidic ion-exchange resin. A method for preparing a modified catalyst for production.   The preparation method according to claim 1, wherein the sulfur-containing amine compound is one or more selected from mercaptoalkylamines, thiazolidines and mercaptoalkylpyridines. The preparation method according to claim 1 or 2, wherein the acid used in the acid aqueous solution is one or more organic acids selected from aromatic sulfonic acids, alkylsulfonic acids, acetic acid and formic acid. The preparation method according to claim 3, wherein the aqueous acid solution is a 0.01 to 5% by mass aqueous solution of an aromatic sulfonic acid. The preparation method according to claim 4, wherein the aqueous acid solution is a 0.03 to 2% by mass aqueous solution of aromatic sulfonic acids. The preparation method according to claim 1 or 2, wherein the acid used in the acid aqueous solution is one or more inorganic acids selected from phosphoric acid, boric acid and sulfuric acid. The preparation method according to claim 6, wherein the aqueous acid solution is a 0.01 to 8% by mass aqueous solution of phosphoric acid. The preparation method according to claim 7, wherein the aqueous acid solution is a 0.05 to 3 mass% aqueous solution of phosphoric acid. Acid aqueous solution, preparation method according to claim 1 or 2 is an acidic aqueous solution obtained in the washing process of the sulfonic acid type ion exchange resin.   The preparation method according to any one of claims 1 to 9, wherein the strongly acidic ion exchange resin is modified with a sulfur-containing amine compound at 0 to 120 ° C. The preparation method according to any one of claims 1 to 10, wherein a target modification rate of the strongly acidic ion exchange resin with the sulfur-containing amine compound is 5 to 45%. The injection of the acid aqueous solution and the sulfur-containing amine compound is injection of a preparation solution in which the sulfur-containing amine compound is dissolved in the acid aqueous solution, and the injection amount of the preparation solution is 0.1 to 20 h ⁻¹ in LHSV (liquid space velocity). The preparation method according to claim 1. The preparation method according to claim 12, wherein an injection amount of the preparation liquid in which the sulfur-containing amine compound is dissolved in the acid aqueous solution is 0.2 to 10 h ^-1 in terms of LHSV (liquid space velocity).