JPS6383031A - Production of dehydrogenation reaction product or hydrogenation reaction product - Google Patents

Abstract

PURPOSE:To circulate a catalyst dispersion through a reaction system for use, by carrying out dehydrogenation or hydrogenation reaction using a Pd based solid catalyst, introducing a reaction solution into a filtering machine capable of automatically discharging filter cakes in a hermetically sealed system to separate the catalyst and washing the catalyst with a reaction solvent. CONSTITUTION:Dehydrogenation reaction e.g. cycloalkene ring aromatic ring, or hydrogenation reaction, e.g. acetylene alcohol olefin alcohol, is carried out in the liquid phase in the presence of a Pd based solid catalyst and the resultant reaction solution is introduced into a filtering machine capable of automatically discharging filter cakes in a hermetically sealed system to separate the catalyst, which is then washed with a reaction solvent and prepare a catalyst dispersion. The resultant catalyst dispersion is then circulated through the reaction system for use. A recovered reaction solvent by distilling the filtrate is economically used as the reaction solvent. Catalyst loss, danger of ignition, deterioration in reaction yield in repeated use, etc., can be suppressed and handling of the sludgelike filter cakes can be avoided. The catalyst life is prolonged at the same time.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a method for producing a dehydrogenation reactant or a hydrogenation reactant, and more specifically, to a method for producing a dehydrogenation reaction product or a hydrogenation reaction product, and more specifically, a method for producing a dehydrogenation reaction product or a hydrogenation reaction product in the presence of a palladium-based solid catalyst. This invention relates to a method for carrying out a hydrogenation reaction.

(Prior Art) A method of carrying out a dehydrogenation reaction or a hydrogenation reaction of a raw material compound in the presence of a palladium-based solid catalyst is conventionally known. As a dehydrogenation reaction, for example, a method of converting a cycloalkene ring into an aromatic ring (JP-A No. 54-19971, No. 56
-105160, etc.), and examples of the hydrogenation reaction include, for example, a method of partially hydrogenating acetylene alcohol or alkynyl alcohol to produce the corresponding olefin alcohol (Japanese Patent Publication No. 1280/1983,
No. 326, No. 51-110507, No. 60-9793
7 etc.) and a method of converting a cycloalkenone into a cycloalkanone (Japanese Patent Publication No. 55-12883 etc.).

In order to reuse a catalyst that has been used once in these reactions, a method is generally used in which the catalyst is removed from the reaction system by an operation such as filtration and then reinjected into the reactor.

However, in this method, (1) a loss of about 5% occurs in the step of removing the catalyst by filtration and introducing it into the reactor;
2) It is necessary to handle the sludge-like filter slag, (3)
) Since the catalyst is taken out, there is a risk of ignition due to contact with the atmosphere. (4) The life of the catalyst will be shortened. (5)
There were problems such as a decrease in reaction yield upon repeated use.

(Problems to be Solved by the Invention) Therefore, the inventors of the present invention have attempted to solve these problems (as a result of extensive efforts, we have conducted a dehydrogenation or hydrogenation reaction using a palladium-based solid catalyst, and recovered and reused the catalyst. It has been discovered that the above-mentioned drawbacks (1) to (5) can be solved by carrying out the steps in a closed system, and based on this knowledge, the present invention has been completed.

(Means for Solving the Problems) Thus, according to the present invention, after the dehydrogenation reaction or hydrogenation reaction of the raw material compound is carried out in the liquid phase in the presence of a palladium-based solid catalyst, the filter cake is automatically removed in a closed system. The reaction solution is introduced in a filtration-like manner that can be discharged, the catalyst is separated as a filtrate, and the filtrate is then washed with a reaction solvent to prepare a catalyst dispersion, which is then recycled to the reaction system. A method for producing a dehydrogenation reactant or a hydrogenation reactant is provided.

The dehydrogenation reaction or hydrogenation reaction using a palladium-based solid catalyst in the present invention is not limited to any conventional reaction.

Specific examples of dehydrogenation include, for example, a method of synthesizing 4-hydroxyquinoline in the presence of a palladium-carbon catalyst (US Pat. No. 2,558,211), a method of synthesizing 4-oxo-4,5, Method for converting 6,7-titrahydroindole to 4-hydroxyindole (JP-A-54-19971, JP-A-56-1031)
No. 50), etc. In addition, as a hydrogenation reaction, a method of converting acetylene alcohol or its derivatives to allyl alcohol or olefin alcohol in the presence of a palladium-calcium carbonate catalyst (% Kosho 27-1280
No., JP-A-56-12326, Hino 151-11050
7, No. 60-97957, etc.), a method for converting a cyclobentenone rust conductor into a cyclopentanone derivative in the presence of a palladium-carbon catalyst (Japanese Patent Publication No. 12883/1983)
etc.

The palladium-based solid catalyst used in the present invention contains palladium as a catalytically active component, and specific examples include palladium-carbon, palladium black,
Examples include colloidal palladium, palladium-calcium carbonate, palladium-barium sulfate, palladium-silica gel, palladium-aluminum oxide, and the like.

The reaction solvent of the present invention is not particularly limited as long as it is inert to the reaction product, and any solvent that is normally used in dehydrogenation or hydrogenation reactions may be used.

Further, various conditions related to the reaction, such as reaction time, reaction temperature, pressure, amount of catalyst added, etc., differ for each reaction and are appropriately selected.

In the present invention, the dehydrogenation or hydrogenation reaction and the catalyst recovery and reuse steps are performed in a closed system.

After the reaction is completed, the reaction product liquid containing the solid catalyst is introduced into a filter, and the catalyst is separated as a filtrate. The filtration machine used is a closed system capable of automatically discharging the filtrate. For example, the filtration dregs are scraped off by a scraping device, and the filter dregs are also scraped off by a suction IJ installed inside the filtration machine.

- A type that can be discharged to the outside of the filtration facility using a conveyor, and specifically, Miura Chemical Equipment Type A ultra filter, concave type ultra filter, type ■ type ultra filter, etc. are used.

After filtering the catalyst, the reaction bath agent is recovered by distilling the F solution.Also, the reaction product in the nonvolatile fraction can be obtained by performing operations such as distillation and crystallization. .

The catalyst recovered as a filtrate is washed with a reaction M agent and prepared into a catalyst dispersion. In this case, it is preferable to use a recovered bath agent as a reaction solvent from the viewpoint of economy. The catalyst dispersion prepared in this manner is reintroduced into the reaction system and recycled.

A specific example of the present invention will be explained below with reference to the drawings.

In FIG. 1, a raw material is supplied from a tube 1 provided in a reactor 2, and a catalyst dispersion liquid is supplied from a tube 11, respectively, to the reactor 2, where a dehydrogenation reaction or a hydrogenation reaction is carried out. The reaction product liquid is introduced into a filter 4 through a pipe 3, and the catalyst is separated as a filtrate. The liquid is transferred from tube 5 to distiller B, and the solvent is recovered from tube 7 by distillation. After solvent distillation, the non-volatile fraction is fed to a purification process where the desired product is obtained through tube 10 by techniques such as crystallization and distillation.

The recovered solvent is introduced into the filter 4 through a pipe 7, and the catalyst remaining as slag is washed away to prepare a catalyst dispersion liquid, which is then introduced into the reactor 2 through a pipe 11.

(Effects of the Invention) According to the present invention, compared to the prior art, (1) catalyst loss can be suppressed, (2) handling of sludge-like filter slag can be avoided, and (3) catalyst (4) The life of the catalyst is extended (5) The reduction in reaction yield during repeated use can be suppressed.

(Examples) The present invention will be described in more detail with reference to Examples below. Parts and percentages in Examples and Comparative Examples are based on weight unless otherwise specified.

Example 1 60 parts of 4-oxoindole, 12 parts of 10% palladium-carbon catalyst, 1000 butyl cellosolve as solvent
A dehydrogenation reaction was carried out at 170°C for 8 hours.
-Hydroxyindole was synthesized. Next, the reaction product liquid was introduced into a pressurized leaf filter (manufactured by Miura Chemical Equipment, Model I (Type Ultra Filter HOR8)) and filtered. It was scraped off by a collecting device and deposited on the screw conveyor at the bottom of the filter.The p liquid was transferred to a distiller, and after recovering butyl cellosolve by distillation, the non-volatile fraction was transferred to another container and crystallized. , the product was obtained with a yield of 8o%.

On the other hand, butyl cellosolve recovered by distillation was supplied to a filter, and the catalyst deposited on the conveyor was washed to prepare a catalyst liquid, which was poured into the reactor.

At this time, by rotating the screw conveyor in the opposite direction to the discharge direction, the catalyst was dispersed in the solvent and the transfer line was prevented from closing.

Next, 4-oxoindole was introduced into the reactor containing the recovered catalyst preparation liquid, and a dehydrogenation reaction was carried out in the same manner as above. The yield of the 4-hydroxyindole obtained was 80%.

This operation was repeated for 30 batches, but there was no decrease in reaction yield or reaction rate due to deterioration of the catalyst.

Example 2 100 parts of 3-bekifun-1-ol, Lindlar catalyst (
5% pa/cacO3) 2 parts, hexa7 as solvent
100 parts were charged and a partial hydrogenation reaction was carried out for 10 hours at 20'O under normal pressure and stirring while supplying hydrogen gas,
Cis-3-hexen-1-ol was synthesized. After the reaction was completed, the hydrogen was replaced with nitrogen, and the mixture was introduced into a pressurized leaf filter (Miura Chemical Equipment, H-type Ultrafilter HOR8 model) and filtered.

The catalyst collected as slag on the surface of the filter inside the filter is scraped off by a scum scraping device, and the OF liquid deposited on the screw conveyor at the bottom of the filter is transferred to a distiller, where hexane is recovered and distilled. The non-volatile fraction was transferred to another distiller and distillation of cis-3-hexen-1-ol was carried out with a yield of 97.
% product was obtained.

The catalyst deposited on the conveyor was washed with hexane recovered by distillation to prepare a catalyst liquid, which was poured into the reactor. The transfer method was the same as in Example 1.

Next, 3-hexyn-1-ol was introduced into the reactor containing the recovered catalyst preparation liquid, and a partial hydrogenation reaction was carried out in the same manner as above. The yield of 3-hexyn-1-ol obtained was 97%. This operation was repeated and 30 batches of operation were performed, but there was no decrease in the reaction yield or reaction rate due to deterioration of the catalyst.

Comparative Example 1 The same operation as in Example 1 was carried out except that the filtered catalyst was taken out of the reaction system and the recovered catalyst was reintroduced into the reactor together with the solvent. As a result, the reaction yield was 75% in the second patch, 67 in the third patch, and 50% in the fourth patch.
As the operation cooled down, the catalyst's lifespan was shortened. In addition, in the process of taking the catalyst out of the system and putting it into the reactor, the catalyst is in the form of sludge, which requires a lot of effort to handle, and some of the catalyst sticks to the inside of the reactor, resulting in a recovery rate of about 5%. In addition, since the recovered catalyst has been reduced by hydrogen, there is a risk of ignition if it is dried in the air, so it was necessary to immediately immerse it in water.

[Brief explanation of the drawing]

FIG. 1 is a flow sheet showing one embodiment of the present invention. 2... Reactor 4... Filter machine 6.
...Evaporator 9 ...Purifier patent applicant Nippon Zeon Co., Ltd. Figure 1

Claims (1)

[Claims] 1. After carrying out the dehydrogenation reaction or hydrogenation reaction of the raw material compound in the liquid phase in the presence of a palladium-based solid catalyst, the reaction solution is introduced into a closed system filter that can automatically discharge the filtrate to remove the catalyst. A method for producing a dehydrogenation reactant or a hydrogenation reactant, which comprises separating the filtrate as a filtrate, washing the filtrate with a reaction solvent to prepare a catalyst dispersion, and recycling it to a reaction system.