JPH11240855A - Reaction method and reaction apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reaction method in which a liquid raw material is reacted under pressure in the presence of a suspension catalyst, and a suspension catalyst and a reaction mixture are separated by cross-flow filtration. And a loop-type reactor used for the method. SOLUTION: A reaction vessel having a liquid material supply port and a reaction mixture outlet, a circulation pump for circulating the reaction mixture, and a loop-type reaction apparatus constituted by a filter are used. The suspension is circulated through the system at a linear speed of 2 seconds, and the suspended catalyst is filtered from the reaction mixture containing the suspended catalyst by a cross flow method using a filter having a pore size of 0.01 to 1.0 μm. In addition, by giving a pulsation to the filter that has been operated for a long time, the filter can be easily regenerated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a reaction method and a reaction apparatus. More specifically, at least a reaction vessel equipped with a liquid material supply port and a reaction mixture outlet, a circulation type pump for circulating the reaction mixture and a loop type reaction apparatus including a filter, and using the reaction apparatus, The present invention relates to a reaction method in which a liquid raw material is reacted under pressure in the presence of a suspension catalyst, and a reaction mixture is separated from the suspension catalyst and a reaction product by cross-flow filtration while circulating the reaction mixture in a reactor at a specific linear velocity.

[0002]

2. Description of the Related Art Conventionally, a liquid which performs a reaction using a solid catalyst is used.
Many solid reactions or gas-liquid-solid reactions are known. In these reactions, the reaction mixture and the catalyst are usually separated by a filter or a centrifuge, and the separated catalyst is washed or adjusted with a solvent and reused by circulation. However, such an operation is extremely complicated, and in particular, when the reaction system is performed at a high pressure, when the catalyst is to be separated by the existing separation device as described above, the system is set to normal pressure or normal pressure before separation. It needs to be carried out in the vicinity, and a special supply device is required to return the separated catalyst to the high-pressure reaction vessel.

[0003]

The construction of a rational process that does not require complicated operations is an indispensable technical problem when performing production on an industrial scale. JP-A-5-76779 discloses that
A catalyst separation method is disclosed in which a filter is pretreated with a carboxylic acid, and the ether carboxylic acid and the suspended catalyst are separated by cross-flow filtration. According to this method, unlike the conventional method, the solid catalyst is continuously separated from the reaction mixture containing the solid catalyst without using a batch type separation means such as a filter or a centrifuge to separate the catalyst. It can be said that this is a rational method because the separated catalyst can be reused as it is.

However, it has been found that, when the reaction is carried out under pressure by the method disclosed herein, depending on the reaction conditions, the filter immediately becomes clogged and may not endure a continuous reaction. Usually, chemical reactions on an industrial scale are often performed continuously under pressure, and it is not an exaggeration to say that clogging of a filter limits the life of industrialization. Further, when a noble metal is used as a suspended catalyst, how to increase the recovery rate of the catalyst is often a turning point of industrialization. Accordingly, an object of the present invention is to provide a reaction method in which a liquid raw material is reacted under pressure in the presence of a suspended catalyst, and the suspended catalyst and the reaction mixture are separated by filtration. And a reactor.

[0005]

Means for Solving the Problems The present inventors have conducted intensive studies, and when performing a pressurized reaction in the presence of a suspended catalyst using a liquid raw material, a linear mixture of the liquid mixture circulating in the reactor is required. The inventors have found that the above problems can be solved by selecting the speed and the pore size of the filter, and have completed the present invention.

That is, the present invention uses a loop-type reaction apparatus comprising at least a reaction vessel provided with a liquid material supply port and a reaction mixture outlet, a circulation pump for circulating the reaction mixture, and a filter. In a reaction method in which a liquid raw material is reacted under pressure in the presence of a suspension catalyst, a reaction mixture is circulated at a linear velocity of 1 to 10 m / sec, and a reaction is generated by a filter having a pore diameter of 0.01 to 1.0 μm. This is a reaction method characterized in that a product and a suspended catalyst are separated by a cross-flow filtration, and a reaction product is extracted out of the system.

Another aspect of the present invention is to provide a loop type reaction system comprising at least a reaction vessel having a liquid material supply port and a reaction mixture outlet, a circulation pump for circulating the reaction mixture, and a filter. Device.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The reaction vessel used in the present invention may have any shape as long as it has a liquid material supply port and a reaction mixture outlet, and uses a gas such as a hydrogenation reaction or a reductive amination reaction. In the case of performing the reaction, a gas supply port may be separately provided.

It is preferable to install a stirrer equipped with paddle blades or turbine blades in the reaction vessel so that the gas is well dissolved with the liquid raw material and in order to improve the mixing state. Further, it is preferable to provide an ejector in a reaction vessel provided with a liquid material supply port, since the gas can be dispersed well. Both a stirrer and an ejector may be provided. The shape of the reaction vessel is not particularly limited, but an annular one is preferable because it is easy to manufacture and has excellent pressure resistance.

In the present invention, the reaction mixture and the suspended catalyst are separated by a filter. If the pore size of the filter is too small, the reaction product is difficult to escape. In the present invention, it is necessary to use a filter having a pore diameter of 0.1 to 1.0 μm. As a material of the filter, it is needless to say that a material having excellent corrosion resistance is preferable, but it is necessary to have excellent pressure resistance.
From such a viewpoint, a cylindrical filter is preferable, and as a material, a filter made of ceramic and a filter made of sintered metal such as zirconium oxide are preferable. In particular, a ceramic filter is preferable in terms of abrasion resistance.

The reaction to be carried out in the reaction method and the reaction apparatus of the present invention includes, for example, hydrogenation reaction, amination reaction,
The present invention can be applied to an alkylation reaction, a nitrile reaction, an oxidation reaction, a chlorination reaction, a carbonylation reaction, and the like. Liquid raw materials used in the reaction include medicines, pesticides, flavors,
Organic compounds used for chemical reactions such as dyes are exemplified. For example, hexene, butadiene, acetone, methyl ethyl ketone, benzene, dichlorobenzene, toluidine, phenol, aniline, nitrobenzene, nitrobenzenesulfonic acid, nitro T acid, p-aminodiphenylamine, p-nitrophenol, geraniol, fatty acid, fatty acid nitrile , Lauryl alcohol,
p-xylene, isopropanol, butanol, 2,3
Butylene glycol, 1,9-nonandial, 2-methyl-1,8-octanedial, or a mixture thereof can be exemplified.

Among them, dialdehydes such as 1,9-nonandial, 2-methyl-1,8-octanedial or a mixture thereof are unstable, and it is desirable to carry out the reaction in a closed system, and a noble metal catalyst is used. Therefore, it is suitable for the reaction method of the present invention.

The catalyst used in the present invention is a solid catalyst which becomes a suspension when mixed with a liquid raw material. Illustrative of such solid catalysts are nickel, cobalt, copper, silver,
At least one metal catalyst such as platinum, chromium, palladium, manganese, iron, titanium, thorium, magnesium, zinc, tungsten, molybdenum, rhenium and zirconium, or a modification catalyst thereof, a Raney catalyst and silica, alumina, diatomaceous Soil, magnesium,
A catalyst supported on zinc oxide or the like can be given.

In carrying out the reaction, a solvent may be appropriately used. The solvent is generally a solvent generally used for various reactions. Examples of such a solvent include methano-
Alcohols such as toluene, ethanol, propanol, butanol, amyl alcohol, hexanole, 2-ethylhexanol, octanol and ethylene glycol;
Examples thereof include aliphatic hydrocarbons such as hexane, octane, decane, liquid paraffin, and cyclohexane. It is needless to say that the solvent used for preparing the catalyst and the solvent used for the reaction are preferably of the same type. In particular, in the case of a condensation reaction in which water is generated, it is desirable that the solvent does not dissolve in water. In this regard, it is preferable to use isoamyl alcohol and butanol. In the case of a condensation reaction for producing an alcohol, a lower alcohol is preferably used.

The present invention is a loop type reactor comprising at least a reaction vessel provided with a liquid material supply port and a reaction mixture outlet, a circulation pump for circulating the reaction mixture, and a filter. Is a reaction method in which a reaction is carried out under predetermined operating conditions using The reaction mixture withdrawn from the reaction vessel is circulated at a predetermined linear velocity in the reactor, and the reaction product and the suspended catalyst are cross-filtered by a filter having a pore diameter of 0.1 to 1.0 μm. And the reaction product is extracted out of the reaction system. The reaction system may be a continuous system or a batch system, but the effect of the present invention is particularly well exhibited in the case of a continuous system.

In the present invention, the reaction is carried out under pressure, and the pressure is selected from 10 to 200 kg / cm ² · G. The reaction temperature is determined by the solvent and pressure used. The reaction product forms a reaction mixture with the suspended catalyst and unreacted materials, and the reaction mixture is circulated in the reaction system by a circulation pump. In the present invention, the linear velocity is important in relation to the pore size of the filter. It is. If the linear velocity is too low, the filter will be clogged, and if the linear velocity is too high, a load will be applied to the circulation pump, cooler, etc.
/ S, preferably 1.5 to 6 m / s. The liquid level in the reaction vessel may be adjusted as appropriate, but usually it is often carried out at 60% to 80% of the vessel.

In the present invention, a cross-flow filtration is performed to separate the suspended catalyst from the reaction mixture containing the suspended catalyst. Thus, the reaction mixture containing the suspended catalyst flows along the membrane surface and is approximately at right angles to the flow of the catalyst-free reaction mixture flowing through the filter, so that the suspended catalyst settles to the filter contact surface. In addition, catalyst particles smaller than the surface pore size of the filter are deposited in the pores of the filter, and the filtration effect due to the substantially reduced pore size of the filter is doubled.

According to the above-described reaction method of the present invention in which a liquid raw material is reacted in the presence of a suspension catalyst, and the suspension catalyst and the reaction mixture are separated by cross-flow filtration, the reaction with less clogging of the filter is performed. Although a method can be provided, in the case of continuous operation for a long time, the filter is not clogged at all. As a guide for the regeneration time of the filter, the time at which the amount of the reaction mixture taken out slightly decreases may be used. Alternatively, regeneration may be performed after detecting a pressure difference between before and after the filter and reaching a predetermined value.

In order to regenerate a filter, it is common to prepare a plurality of filters, switch to another filter, and perform backwashing and cleaning of the filter that is inactive with gas or liquid. ,
As in the present invention, a suspension catalyst is used and the pore size is 0.0
When the catalyst and the reaction mixture are separated under pressure using a filter of 1 to 1.0 μm, it is very difficult to eliminate clogging of the filter by backwashing with gas or liquid. However,
In such a case, clogging of the filter can be easily eliminated by pulsating the filter.

For example, ultrasonic waves can be used to pulsate the filter, but if the filter is switched and the solvent used in the reaction system is supplied to the filter at rest by a plunger pump. It is preferable because pulsation can be easily given to the filter. Since the plunger pump can use a pump for supplying a liquid material, such a point is also preferable. The type of the plunger pump is not limited, and the pulsation cycle is not particularly limited.

Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a flowchart showing an example of a reaction apparatus used in the reaction method of the present invention. 1 is a pump for supplying a liquid material, and 2 is a liquid material supply line. 3 is a reaction vessel, 4 is an ejector, 5 is a gas disperser. First, as a primary charge, a suspended solid catalyst dissolved in a liquid raw material and a solvent from 2 is charged into the reaction vessel 3 to a predetermined liquid level. After reaching the predetermined pressure and temperature, the circulation pump 6 is operated to circulate the liquid material composed of the liquid raw material and the slurry-like solid catalyst through the cooler 7 at a predetermined linear velocity.

When the steady state is reached, a gas such as hydrogen is charged from the gas supply line 5 to start the reaction. When an ejector is provided in the reaction vessel, gas can be blown into the reaction vessel at an increased speed of the circulated liquid reaction mixture, thereby further improving the flow state in the reaction vessel together with the supplied gas, and dispersing the gas. This is preferable because it improves the gas absorption efficiency. The cooler may be provided outside the reaction vessel as shown in FIG. 1 or FIG. 2, or may be provided directly in the reaction vessel in a jacket form. The cooler 7 is also used as a heater if necessary. It is thermally advantageous and efficient for the cooler or heater to exchange heat with another medium. FIG. 2 shows an example in which a stirrer 10 is provided in the reaction vessel 3.

After reaching the predetermined reaction rate, while continuously supplying the liquid raw material and the gas, the valve of the filter 8 on the side where the filtrate flows out is opened, and the suspended catalyst is filtered in a cross-flow manner. The reaction mixture is drawn out of the system. As mentioned above,
In the present invention, since the suspension catalyst is filtered by the cross-flow method, the suspension catalyst can be prevented from settling on the contact surface of the filter, and the effect is doubled. The separated catalyst is circulated to the reaction vessel 3 as it is. The separated reaction mixture may contain a small amount of a solid catalyst in addition to a reaction product and an unreacted product, and is supplied to the next step through the filter 9 as necessary. A slight loss of the catalyst may be appropriately replenished by checking the state of the reaction solution.

In FIG. 1 or FIG. 2, reference numeral 11 denotes a solvent supply line for regenerating the filter 8. When regenerating a filter, the filter is switched to another filter, and a solvent is supplied from the withdrawal side of the reaction mixture of the filter to the inside of the reaction system by using a liquid material supply pump (plunger pump) for the inactive filter. Supply. At this time, a pulsation can be given from the plunger pump to the filter at the same time, and the filter in which the suspended catalyst is clogged is regenerated by 50% or more.

[0025]

The present invention will be described more specifically with reference to the following examples. Example 1 A reaction vessel equipped with an ejector was used, a loop reactor was configured as shown in FIG. 1, and a nickel-diatomaceous earth catalyst was used as a solid catalyst.
A continuous reductive amination reaction of 1-methyl-1,8-octanedial was performed. As reaction raw materials, 8 of 1,9-nonandial and 2-methyl-1,8-octanedial:
The mixture of No. 2 and isoamyl alcohol as a solvent and the above solid catalyst were charged into a reaction vessel.
Atm, a temperature of 150 ° C., a mixture of 1,9-nonandial and 2-methyl-1,8-octanedial at 217 kg / hr and isoamyl alcohol at 61 ° C.
The reaction was carried out by continuously supplying 6 kg / hr, liquid ammonia at 355 kg / hr and hydrogen at 63 Nm ³ / hr, and the reaction mixture was circulated through a cooler set at 140 ° C. at a linear velocity of 5 m / sec.

As a filter, inner diameter 1 cm, height 10 c
m, a ceramic cylinder with a pore diameter of 0.5 μm
Zero and ten parallel installations were used. From the filter, isoamyl alcohol 52 wt%, ammonia 2
1,9-nonanediamine and 2-methyl-1,8-containing 6 wt%, H ₂ O ₄ wt% and 0.05 wt% catalyst
A clear liquid consisting of 17 wt% of the octanediamine mixture was obtained at 20 kg / min. After continuous operation for 30 days, stable operation was possible and no clogging of the filter was observed. The clarified liquid contains 1,9-nonangial and 2
-Methyl-1,8-octanedial was not detected. The clarified solution was passed through a 2 m ² filter to further separate the catalyst, but very little catalyst flowed out of the reaction system.

Example 2 The solvent was changed to butanol, and the linear velocity of the reaction mixture was 2 m /
As a result of carrying out in the same manner as in Example 1 except that the time was changed to seconds, almost the same results as in Example 1 were obtained.

Example 2 Using a reaction vessel equipped with paddle blades, a loop-type reactor was constructed as shown in FIG. 2, and a nickel-diatomaceous earth catalyst was used as a solid catalyst.
A continuous reductive amination reaction of 1-methyl-1,8-octanedial was performed. As reaction raw materials, 8 of 1,9-nonandial and 2-methyl-1,8-octanedial:
2 and methanol as the solvent and the above solid catalyst were charged into a reaction vessel, and the liquid mixture 12
A mixture of 1,9-nonandial and 2-methyl-1,8-octanedial was added to 21 kg so as to obtain 00 kg, a catalyst concentration of 1 wt%, a reaction pressure of 60 atm, and a temperature of 150 ° C.
7 kg / hr, isoamyl alcohol 616 kg / h
r, 355 kg / hr of liquid ammonia and 63 of hydrogen
The reaction was carried out by continuously feeding at Nm ³ / hr, and the reaction mixture was circulated through a cooler set at 140 ° C. at a linear velocity of 5 m / sec.

As a filter, inner diameter 1 cm, height 10 c
A SUS316 sintered metal having a diameter of 0.5 μm and a pore size of 0.5 μm was used in which 10 pieces were placed in series and 10 pieces were placed in parallel. From the filter, methanol 52 wt%, ammonia 26 w
t%, and H ₂ O4wt%, clear liquid consisting of containing 0.05 wt% of the catalyst 1,9-nonanediamine and 2-methyl-1,8-octane diamine mixture 17 wt% 20
kg / min. After continuous operation for 30 days, stable operation was possible and no clogging of the filter was observed. 1,9-Nonandial and 2-methyl-1,8-octanediol were not detected in the clarified liquid.
The clarified solution was passed through a 2 m ² filter to further separate the catalyst, but very little catalyst flowed out of the reaction system.

Example 4 A stirring vessel having two paddle blades shown in FIG. 2 was used as a reaction vessel, and a reactor was used as a filter by a reactor configured as shown in FIG. 2 to have an inner diameter of 1 cm, a height of 10 cm, and a pore size of 0 .5 μm SUS316 sintered metal in 10 pieces in series and 10 pieces in parallel
Using this one, set the linear velocity of the reaction mixture to 2 m /
The same operation was performed as in Example 1 except that the operation time was changed to seconds. As a result, stable operation was possible. 0.01 wt% from the filter
A clear liquid containing the catalyst was obtained.

Example 5 The operation was continued for 240 hours under the conditions of Example 1, and the filter was switched when the amount of the reaction mixture withdrawn decreased to 30% of the value at the start of the operation. A plunger pump (I
Isoamyl alcohol was supplied at a rate of 0.1 m ³ / m ² · hr by CHEMED PUMP manufactured by WAKI. 1
After 5 minutes, when the filter was reused in the reaction system, the output of the reaction mixture recovered to 60% or more of the output at the start of operation. FIG. 3 shows the relationship between the filtration time and the recovery rate of the permeation rate.

Comparative Example 1 The operation was performed in the same manner as in Example 1 except that the linear velocity was changed to 0.5 m / sec. As a result, the filter was clogged in a short time.

[0033]

According to the present invention, when performing a pressurized reaction of a liquid raw material in the presence of a suspended catalyst, the linear velocity of the liquid mixture circulating in the reactor and the pore size of the filter are selected, and the cross-flow filtration is performed. By doing, it is possible to reduce the clogging of the filter, without the need for complicated catalyst separation and recovery operation,
The reaction can be continuously and efficiently performed. Also,
By pulsating the filter, the filter can be easily regenerated.

[Brief description of the drawings]

FIG. 1 is a flowchart showing an example of the reaction method of the present invention.

FIG. 2 is a flowchart showing another example of the reaction method of the present invention.

FIG. 3 is an operation progress chart showing a relationship between a filtration time and a recovery rate of a permeation speed.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 liquid material supply pump 2 liquid material supply line 3 reaction vessel 4 ejector 5 gas supply line 6 circulation pump 7 heater or cooler 8 filter 9 filter 10 stirrer 11 regeneration solvent supply line

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI B01J 23/755 B01D 29/30 520Z C07C 209/16 29/38 510C // C07B 61/00 300 520D B01J 23/74 321X

Claims (8)

[Claims] At least a reaction vessel having a liquid material supply port and a reaction mixture outlet, a circulation pump for circulating the reaction mixture, and a loop type reaction apparatus comprising a filter are used to suspend the liquid material. In a reaction method in which a reaction is performed under pressure in the presence of a turbid catalyst, the reaction mixture is subjected to a linear velocity of 1
While circulating at a rate of 10 to 10 m / sec, the pore diameter is 0.01 to 1.
A reaction method wherein a reaction product and a suspended catalyst are separated by a cross-flow filtration with a 0 μm filter, and the reaction product is extracted outside the system. 2. The reaction method according to claim 1, wherein the filter is a filter regenerated by applying pulsation. 3. The reaction method according to claim 1, wherein the reaction vessel is an annular reaction vessel. 4. The reaction method according to claim 1, wherein said filter is a cylindrical filter. 5. The reaction method according to claim 1, wherein said filter is a ceramic filter. 6. The reaction method according to claim 1, wherein the liquid raw material is 1,9-nonandial and / or 2-methyl-1,8-octanedial. 7. The method according to claim 1, wherein said suspension catalyst is a noble metal catalyst.
Any one of the reaction methods of any one of (1) to (6). 8. A loop reactor comprising at least a reaction vessel having a liquid material supply port and a reaction mixture outlet, a circulation pump for circulating the reaction mixture, and a filter.