KR20060117905A - Method of preparing modified catalyst for bisphenol a production - Google Patents

Abstract

A method of preparing a modified catalyst for bisphenol A production by partially modifying a strongly acid ion-exchange resin with a sulfurized amine compound. It comprises packing a strongly acid ion- exchange resin into a fixed-bed reactor, introducing therein an aqueous acid solution, and further introducing a sulfurized amine compound in such an amount that its concentration in the aqueous acid solution reaches equilibrium to thereby modify the strongly acid ion-exchange resin. By the method, the strongly acid ion-exchange resin is evenly modified without breaking, and a modified catalyst for bisphenol A production which has excellent catalytic performance can be prepared.

Description

METHODS OF PREPARING MODIFIED CATALYST FOR BISPHENOL A PRODUCTION

The present invention relates to a method for preparing a catalyst for use in the preparation of bisphenol A [2,2-bis (4-hydroxyphenyl) propane], in particular, a strongly acidic ion exchange resin is partially modified with a sulfur-containing amine compound. It 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 resins, polyarylate resins, or epoxy resins, and in recent years, the demand tends to increase.

In preparing this bisphenol A, a strongly acidic ion exchange resin partially modified with a sulfur-containing amine compound is used as a catalyst, and as a preparation method of such a catalyst, a sulfur-containing amine compound is added in a fixed bed reactor to modify the sulfonic acid type ion exchange resin. The method is adopted.

Usually, when a sulfur-containing amine compound is added in batch in a fixed bed reactor to modify a sulfonic acid type ion exchange resin, the sulfur-containing amine compound is moved by an acid to transfer sulfonic acid groups in the fixed phase resin (adsorption to sulfonic acid groups and sulfonic acid groups). Escape and move). 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, in the movement 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 of about 30 to 80%), and low at the inlet of the fixed bed reactor (modification rate is 5). To about 30% low modification rate), there is a problem that the sulfonic acid type ion exchange resin is not uniformly modified by only one movement.

The cation exchange resin fixed phase neutralized with the sulfur-containing amine compound is prepared by various methods. For example, a method for preparing an acidic cation exchange resin fixed phase in which the acidic cation exchange resin has been neutralized with the sulfur-containing amine compound (e.g. 296871, Japanese Patent Application Laid-Open No. 2001-286770, Japanese Patent Application Laid-Open No. 1996-40961, and Japanese Patent Application Laid-Open No. 2001-288132. In addition, a method of circulating an aqueous solution containing a sulfur-containing amine compound containing hydrochloric acid in a resin stationary phase is disclosed (see, for example, Japanese Patent Application Laid-Open No. 1978-14680). However, using a large amount of hydrochloric acid may cause corrosion of the equipment. .

In addition, as a method for preparing a catalyst for producing bisphenols, a method of injecting a lean solution of a sulfur-containing amine compound while stirring an ion exchange resin in a reaction vessel (see, for example, Japanese Unexamined Patent Publication No. 1997-24279), an acidic cation in a reactor A method of uniformly neutralizing an acidic cation exchange resin by filling an exchange resin, charging or charging an aqueous solution of a sulfur-containing amine compound, and then flowing bubbles from the bottom of the reactor (see, for example, Japanese Patent Application Laid-Open No. 2000-254523). ) Is disclosed. However, in the former case, a large-scale lean solution storage facility is required, and since it is a batch production by impeller stirring, breakage of an ion exchange resin occurs, and refilling of an ion exchange resin is required for formation of a stationary phase. In the latter case, since the preparation is carried out at pH 6 or higher, it is difficult to homogenize the sulfur-containing amine compound, which causes a problem that the catalyst performance is lowered because it becomes a heterogeneous modified catalyst.

Disclosure of the Invention

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is to provide a method for preparing a modified catalyst for producing bisphenol A, in which no strong acidic ion exchange resin is damaged, the strong acidic ion exchange resin is uniformly modified, and excellent in catalytic performance. .

MEANS TO SOLVE THE PROBLEM As a result of earnestly researching in order to solve the said subject, as a result, it filled with a strong acidic ion exchange resin to the fixed-bed reactor, inject | poured the acid aqueous solution and the sulfur containing amine compound of the concentration which becomes equilibrium in this acid aqueous solution, It has been found that the above object is achieved by performing modification of the exchange resin. The present invention has been completed based on this finding.

That is, the present invention provides 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, wherein a fixed acid reactor is filled with a strongly acidic ion exchange resin, the aqueous solution and the It is to provide a method for preparing a modified catalyst for producing bisphenol A, characterized in that a strong acidic ion exchange resin is modified by injecting a sulfur-containing amine compound at an equilibrium concentration in an acid solution.

As the strongly acidic ion exchange resin used in the present invention, sulfonic acid type ion exchange resins such as sulfonated styrene-divinylbenzene copolymer, sulfonated crosslinked styrene polymer, phenol formaldehyde-sulfonic acid resin, and benzene formaldehyde-sulfonic acid resin Etc. can be mentioned. Strongly acidic ion exchange resin is charged to the fixed bed reactor. Since the ion exchange resin is directly charged to the stationary phase, the ion exchange resin is not damaged in the modification step of the ion exchange resin and there is no movement from the batch reactor or the modified catalyst preparation container, which is advantageous in terms of production cost.

In the present invention, examples of the sulfur-containing amine compound used for modifying the strongly acidic ion exchange resin include mercaptopyridines such as 3-mercaptopyridine, mercaptoalkylamines such as 2-mercaptoethylamine, and 2,2-dimethyl. Thiazolidines such as thiazolidine, aminothiophenols such as 4-aminothiophenol, and pyridine alkanine thiols such as 4-pyridine ethanethiol. Of these, 4-pyridine ethanethiol, 2,2-dimethylthiazolidine and 2-mercaptoethylamine are preferable. These can be used individually by 1 type or in combination of 2 or more type.

The modification rate of the strongly acidic ion exchange resin by the sulfur-containing amine compound is usually about 5 to 45%, preferably 8 to 35%, more preferably 10 to 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 not shortened or the catalyst activity or selectivity is not lowered. Here, the "modification rate" of the strongly acidic ion exchange resin means the molar modification rate by the sulfur-containing amine compound of the strongly acidic ion exchange group of the strongly acidic ion exchange resin.

As the acid, organic acids and inorganic acids can be used. Examples of the acid of the organic acid include aromatic sulfonic acids such as benzene sulfonic acid, paratoluene sulfonic acid and xylene sulfonic acid, alkyl sulfonic acids such as methanesulfonic acid and ethanesulfonic acid, acetic acid and formic acid. Among these, aromatic sulfonic acids are preferable, and paratoluene sulfonic acid is more preferable. Moreover, the acidic aqueous solution obtained by the water washing process of sulfonic-acid type ion exchange resin is also suitable. Examples of the acid of the inorganic acid include phosphoric acid, boric acid, sulfuric acid, and the like, and phosphoric acid is preferable. The use of aromatic sulfonic acids or phosphoric acid has the advantage of little corrosion of the 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, alkyl sulfonic acids and sulfuric acid. When using weak acids, such as an acetic acid, formic acid, and phosphoric acid, it is about 0.01-8 mass% normally, Preferably it is 0.05-3 mass%. When the upper limit of the concentration of the acid is set 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 to be balanced in the acid aqueous solution (hereinafter referred to as "equilibrium concentration of the sulfur-containing amine compound" Since the amount of the acid used and the loss of the sulfur-containing amine compound are small, it is economically preferable. Moreover, since the equilibrium concentration of a sulfur containing amine compound does not become low too much by making the minimum of acid concentration into about 0.01 mass%, the time required for denaturation does not become too long.

Here, the equilibrium concentration of the sulfur-containing amine compound in the acid aqueous solution is calculated as follows. For example, an acid solution is added to the water-swelled strongly acidic ion exchange resin, stirring and filtration are repeated, water is replaced with an acid solution, and then a 10% by mass aqueous solution of the sulfur-containing amine compound is slowly added while stirring the ion exchange resin. . On the other hand, heretofore, it is a batch catalyst preparation. A portion of this aqueous solution is then sampled and a total nitrogen analysis is performed to determine the concentration of the sulfur containing amine compound from the total nitrogen concentration.

In this invention, it is preferable to replace the water contained in the fixed phase (strongly acidic ion exchange resin) of a fixed-bed reactor with an acid aqueous solution before modification of strong acidic ion exchange resin. This is because the water-swelling type of the gel ion exchange resin usually used as a strongly acidic ion exchange resin contains water of about 50% by mass. By carrying out such substitution, the effect of keeping the acid concentration constant when circulating and recycling the aqueous acid solution flowing out of the outlet of the reactor is obtained.

The temperature of the catalyst aid (modification of the strongly acidic ion exchange resin by the sulfur-containing amine compound) is usually about 0 to 120 ° C, preferably 20 to 100 ° C. By setting the upper limit of the catalyst preparation temperature to about 120 ° C, decomposition of the ion exchange resin does not occur, and by setting the lower limit to about 0 ° C, there is no problem that the acid aqueous solution is solidified.

Injection of an acid aqueous solution and a sulfur containing amine compound is normally performed by injecting the preparation liquid which melt | dissolved the sulfur containing amine compound in the acid aqueous solution. Injection amount of the aqueous solution is usually in terms of acid concentration and the time to prepare a LHSV (liquid space velocity) of 0.1 to 20h ^-1, preferably about 0.2 to about 10h ^-1, more preferably from 0.4 to 5h ^-1. Moreover, the line speed 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 the preparation of the catalyst is determined by the acid concentration or acid type in the aqueous acid solution, the equilibrium concentration of the sulfur-containing amine compound, the modification rate of the strongly acidic ion exchange resin by the sulfur-containing amine compound, and LHSV. The amount of sulfur-containing amine compound consumed in the catalyst preparation is determined by the rate of modification. 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 the catalyst preparation, a certain amount of the preparation liquid in which the sulfur-containing amine compound is dissolved in an aqueous acid solution is injected from the inlet of the fixed bed reactor, and the preparation liquid passed through the strongly acidic ion exchange resin packed in the reactor flows out from the outlet of the fixed bed reactor. . As the treatment of the preparation liquid, there is a method of discarding or circulating and recycling. However, the method of circulating and recycling is preferable since the amount of the waste liquid is small and the amount of the sulfur-containing amine compound and acid is reduced. In the case of circulating 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 the sulfur-containing amine compound is added in an amount such that the sulfur-containing amine compound becomes an equilibrium concentration. The concentration of the sulfur-containing amine compound can be determined by measuring the nitrogen concentration in the preparation liquid containing the sulfur-containing amine compound and an acid. Since the total injection time is roughly determined by the equilibrium concentration of the sulfur-containing amine compound to be injected or the modification rate of the ion-exchange resin, the measurement interval of the sulfur-containing amine compound concentration can be usually every 2 to 20 hours. On the other hand, when the preparation liquid containing a sulfur containing amine compound and an acid is circulated, the injection amount (circulation amount) to a fixed bed reactor can be LHSV and ship speed as mentioned above.

In the catalyst preparation, the flow of the preparation liquid comprising the acid and the sulfur containing amine compound in the fixed bed reactor may be any of downflow and upflow. However, in the case of upflow, since the amount of preparation of the preparation liquid is increased, the development (float, flow, etc.) of the ion exchange resin increases, so in the present invention, downflow is preferable.

Bisphenol A is produced using a modified catalyst prepared as described above and using phenol and acetone as raw materials. The addition of the modified catalyst to the raw material in the fixed bed reactor can be added under almost the same conditions as those for preparing the catalyst (LHSV and vessel speed). Although there is no restriction | limiting in particular about the usage ratio of a phenol and acetone, The quantity of unreacted acetone is preferable as much as possible from a viewpoint of the ease of purification and economical efficiency of the bisphenol A produced | generated, Therefore, it is preferable to use phenol more than stoichiometric amount. It is advantageous. 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 any of batch and continuous, but a fixed bed continuous reaction method in which phenol and acetone are continuously supplied to a reaction column filled with a modified catalyst and reacted is preferable.

According to the present invention, it is possible to prepare a modified catalyst for producing bisphenol A, in which there is no breakage of the strongly acidic ion exchange resin, the strongly acidic ion exchange resin is uniformly modified, the time for uniform modification is short, and the catalyst performance is excellent.

Next, although an Example demonstrates this invention further more concretely, this invention is not limited at all by these.

Example 1

As the reactor, four reactors each having an inner diameter of 10 mm and a length of 1200 mm were connected in series, further connected with an outlet side and an inlet side by a pipe, and a reactor in which the preparation liquid discharged from the reactor outlet was circulated to the inlet side was used. This reactor was filled with 300 milliliters of sulfonic acid type cation exchange resin (manufactured by Mitsubishi Chemical Industries Co., Ltd., trade name Diaion SK-104) in a water-swelled state, and then downflowed to 1500 milliliters of distilled water. Washed. Subsequently, the water in the reactor and the piping were replaced with a 0.3 mass% phosphoric acid aqueous solution. 300 milliliters / h (LHSV = 1h ⁻⁾ of the preparation solution in which 2,2-dimethylthiazolidine was added to a 0.3 mass% phosphoric acid aqueous solution so that the concentration of 2,2-dimethylthiazolidine was 117 mass ppm. ¹ , line speed = 3.8 m / h). The target denaturation rate by 2,2-dimethylthiazolidine was 23%, and the preparation was continuously injected for 298 hours to modify the ion exchange resin at 25 ° C. The preparation liquid discharged from the fourth reactor outlet was recycled by circulating in the first reactor. At this time, 2,2-dimethylthiazolidine content in the preparation liquid which flowed out from the 4th reactor outlet is measured every 20 hours by a total nitrogen analyzer, and 2,2-die of the quantity which maintains 117 mass ppm is carried out. Methylthiazolidine was added.

After the injection of the preparation liquid which added 2, 2-dimethyl thiazolidine to the aqueous solution of phosphoric acid was complete | finished, the modified catalyst was taken out from the reactor and the aqueous solution of phosphoric acid was removed with distilled water. This 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 the titration method using the sodium hydroxide aqueous solution, the neutralization rate was computed based on the following formula, and this neutralization rate was made into the denaturation rate.

Neutralization rate (%) = 100 x {1- [acid equivalent of modified resin (meq./g) / acid equivalent of unmodified resin (meq./g)]}

Example 2

In Example 1, the preparation liquid containing 440 mass ppm of 440 mass ppm of 2, 2- dimethyl thiazolidines prepared using 1.0 mass% phosphoric acid aqueous solution instead of 0.3 mass% phosphoric acid aqueous solution was injected continuously for 79 hours. Was modified in the same manner as in Example 1 to obtain a modified catalyst. Evaluation similar to Example 1 was performed about the obtained modified catalyst. The results are shown in Table 1.

Example 3

In Example 1, using the preparation liquid containing 52 mass ppm of 2-mercaptoethylamine instead of 2, 2- dimethyl thiazolidine, the target modification rate is 15%, and this preparation liquid is 280 hours. A modified catalyst was obtained in the same manner as in Example 1 except that the compound was injected continuously. Evaluation similar to Example 1 was performed about the obtained modified catalyst. The results are shown in Table 1.

Example 4

The preparation liquid which contains 131 mass ppm of 2, 2- dimethyl thiazolidines prepared in 0.3 mass% paratoluene sulfonic acid aqueous solution instead of 0.3 mass% phosphoric acid aqueous solution in Example 1 was continuously injected for 266 hours. A modified catalyst was obtained in the same manner as in Example 1 except for this. Evaluation similar to Example 1 was performed about the obtained modified catalyst. The results are shown in Table 1.

Comparative Example 1

Example 1, except that 10.1 g of the total amount of 2,2-dimethylthiazolidine was injected for 0.5 hour, and 0.3 mass% phosphoric acid aqueous solution was cyclically recycled for the same time as in Example 1, except that In the same manner as in the modified catalyst was obtained. Evaluation similar to Example 1 was performed about the obtained modified catalyst. The results are shown in Table 1.

Comparative Example 2

Example 2, except that 10.1 g of the total amount of 2,2-dimethylthiazolidine was injected for 0.5 hour, and 1.0 mass% aqueous phosphoric acid solution was circulated and recycled for the same time as in Example 2. In the same manner as in the modified catalyst was obtained. 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 used amount of 2,2-mercaptoethylamine was injected in 0.5 hour, and 0.3 mass% phosphoric acid aqueous solution was cyclically recycled for the same time as in Example 1, except that The modified catalyst was obtained. Evaluation similar to Example 1 was performed about the obtained modified catalyst. The results are shown in Table 1.

Comparative Example 4

Example 4, except that 10.1 g of the total amount of 2,2-dimethylthiazolidine was used for 0.5 hour, and 0.3 mass% phosphoric acid aqueous solution was cyclically recycled for the same time as that of Example 4. In the same manner as in the modified catalyst was obtained. Evaluation similar to Example 1 was performed about the obtained modified catalyst. The results are shown in Table 1.

According to the present invention, a modified catalyst for producing bisphenol A having excellent catalyst performance can be provided.

Claims (13)

In the method for preparing a modified catalyst for producing bisphenol A, which is formed by partially modifying a strong acidic ion exchange resin with a sulfur-containing amine compound, a fixed acid reactor is filled with a strong acidic ion exchange resin, and equilibrated in an acid aqueous solution and the acid aqueous solution. A method of preparing a modified catalyst for producing bisphenol A, characterized by injecting a sulfur-containing amine compound at a concentration to be used to modify a strongly acidic ion exchange resin. The method of claim 1, A sulfur-containing amine compound is at least one selected from mercaptoalkylamines, thiazolidines and mercaptoalkylpyridines. The method of claim 1, The acid is an organic acid selected from aromatic sulfonic acids, alkylsulfonic acids, acetic acid and formic acid. The method of claim 3, wherein An acid is 0.01-5 mass% aqueous solution of aromatic sulfonic acid, The manufacturing method characterized by the above-mentioned. The method of claim 4, wherein An acid is a 0.03-2 mass% aqueous solution of aromatic sulfonic acids, The manufacturing method characterized by the above-mentioned. The method of claim 1, The preparation method characterized in that the acid is an inorganic acid selected from phosphoric acid, boric acid and sulfuric acid. The method of claim 6, The acid is 0.01-8 mass% aqueous solution of phosphoric acid, The manufacturing method characterized by the above-mentioned. The method of claim 7, wherein The preparation method characterized by the above-mentioned acid being 0.05-3 mass% aqueous solution of phosphoric acid. The method of claim 1, An acid is an acidic aqueous solution obtained by the water washing process of sulfonic-acid type ion exchange resin. The method of claim 1, A preparation method characterized in that modification of the strongly acidic ion exchange resin with a sulfur-containing amine compound is carried out at 0 to 120 ° C. The method of claim 1, A preparation method characterized in that the modification rate of the strongly acidic ion exchange resin by the sulfur-containing amine compound is 5 to 45%. The method according to any one of claims 1 to 11, The injection of the aqueous acid solution and the sulfur-containing amine compound is the injection of a preparation solution in which the sulfur-containing amine compound is dissolved in the aqueous acid solution, and the injection amount of the preparation solution is 0.1 to 20 h ⁻¹ at LHSV (liquid space velocity). Preparation method. The method of claim 12, The sulfur-containing amine compound to the acid aqueous solution injection amount of the liquid preparation was dissolved LHSV (liquid space velocity) in the preparation characterized in that from 0.2 to 10h ^-1.