JPS5848548B2 - Method for producing 4,4'-diaminostilbene-2,2'-disulfonic acid or its salts - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is based on the presence of a Raney nickel catalyst in which 4,l-dinitrostilbene-2,2'disulfonic acid or its salt (hereinafter abbreviated as DNS) is poisoned with an acidic sulfite. 4. by performing catalytic reduction under hydrogen pressure.
The present invention relates to a method for producing 4'-diaminostilbene-2 goudisulfonic acid or a salt thereof (hereinafter abbreviated as DAS).

Among DNS and DAS, salt refers to sodium salt, potassium salt, or ammonium salt.

DAS manufactures dyes, especially fluorescent whitening dyes. It is an important compound as an intermediate for , and requires high purity.

Conventionally, DAS has been produced by reducing DNS with iron powder and acid, but the process of separating the reduced DAS from the iron powder used for reduction is complicated and the iron powder residue is There were problems such as difficulty in processing.

Catalytic reduction is known as a method that does not have these drawbacks and is suitable for continuous mass production. However, in DNS catalytic reduction, nitro groups are reduced to amino groups, and ethylene bonds are also converted to hydrogen. 4,4'-dianodibenzyl-2,2-disulfonic acid or its salt (hereinafter referred to as DAB)
It is abbreviated as S.

) is produced as a by-product, and colored products are produced, which tends to result in low-purity DAS.

Up until now, the methods for producing DAS by catalytic reduction have been as follows: (1) Oil absorption rate of 50~
A method for catalytic reduction of DNS using a palladium or platinum catalyst supported on 190 carbon black.

(2) DN described in JP-A-49-127955
A method of catalytically reducing S in the presence of a palladium-based catalyst and iodine, bromine, or these ions.

(3) DNS described in JP-A-50-12059
is hydrogenated in the presence of a metal from group 8 of the periodic table of elements under a certain range of reaction temperature, pH value of the liquid, and hydrogen pressure to obtain D.
How to get AS.

(4) DNS described in Japanese Patent Application Laid-Open No. 50-84551
A method in which catalytic reduction is carried out in an aqueous solution with a pH of 5 to 10 under a nickel catalyst.

(5) DNS described in Japanese Patent Application Laid-Open No. 50-84550
When catalytically reduced with a nickel catalyst in an alcohol solvent,
A method in which the water content of the system at the start of the reaction is 3% or less.

(6) C- described in JP-A No. 50-93927
An aromatic nitro compound also having a C multiple bond was used as a catalyst with the formula MeSx (wherein X is a number from 1 to 4, and M
e represents a metal atom of Group 8 of the Periodic Table of Elements or rhenium.

) in the presence of metal sulfide.

(7) DNS described in Japanese Patent Application Laid-Open No. 50-93953
There are methods such as catalytic reduction of the cobalt using a cobalt catalyst.

However, Japanese Patent Publication No. 48-815, Japanese Patent Publication No. 4912795
No. 5, JP-A-50-93952, and other methods all use precious metal catalysts, which are much more expensive than the Raney nickel catalyst used in the present invention, and require efficient recovery operations and reuse. It is difficult and uneconomical to do so.

In comparison, Raney nickel used in the present invention is inexpensive and can be easily recovered and reused, so it is very advantageous compared to noble metal catalysts when used industrially.

JP-A-50-12059 discloses a method for obtaining DAS by catalytic reduction in the presence of a metal from group 8 of the periodic table, but Raney nickel is not listed as a specific example of a catalyst. In Example 19 (for comparison), when Raney nickel was used, L.
It is stated that DABS is produced as a by-product and is not desirable.

In the methods of JP-A-50-84550 and JP-A-50-84551, DAS is obtained by catalytic reduction of DNS using a nickel catalyst, but the former uses alcohols with a water content of 3% or less as a solvent. In the latter case, the PH of the reaction solution needs to be recovered after the reaction.
In order to keep the DAS between 5 and 10, a buffer is added, and when DAS is precipitated and collected, the buffer is mixed in and the DAS is collected.
There is a problem of lowering the purity of AS.

In addition, buffering agents will also be present in the sap, contaminating the wastewater.

Example 15 of JP-A-50-93927 describes the use of a nickel sulfide catalyst, but the reaction is carried out at a pressure as high as 150 bar.

This is disadvantageous as it requires a high pressure reactor.

On the other hand, the present inventors have found that if catalytic reduction of DNS is performed using poisoned Rane 41 nickel, DAB
It has been found that the by-product of S is significantly suppressed and DAS of excellent quality can be easily obtained.

The poisoned Raney nickel used to carry out the present invention can be obtained by the following method.

Weigh a predetermined amount of the developed Raney nickel aqueous paste, suspend it in a predetermined amount of distilled water (ion-exchanged water may be used as long as it does not contain harmful heavy metal ions or sulfides), and add the predetermined amount while stirring. Acidic sulfite is added little by little and treated at a predetermined temperature for a predetermined time.

After treatment, remove the supernatant, add fresh distilled water (same as above), stir and wash.

This washing operation is repeated several times and the supernatant liquid is removed by decanting to obtain a poisoned "Raney nickel aqueous paste".

The poisoned Raney nickel aqueous paste thus prepared is used to catalytically reduce DNS under hydrogen pressure.

Catalytic reduction of DNS is 4,4l-dinitrostilbene-2
It can also be carried out by catalytic reduction of a salt of -2'-cissulfonic acid or haso under pressure of hydrogen in the presence of an acidic sulfite and a Raney nickel catalyst.

That is, a predetermined amount of the developed Raney nickel aqueous paste was weighed, this and a portion of the water used for the reduction reaction were transferred into a reactor, a predetermined amount of acidic sulfite was added, stirred, and DNS was contacted under hydrogen pressure. A similar effect can be obtained by reduction.

The acidic sulfite used in the present invention may be any industrially easily available salt, such as acidic sodium sulfite, acidic ammonium sulfite, acidic potassium sulfite, and the like.

1. The amount of acidic sulfite that causes poisoning ranges from 1/100 mole to 1/3 mole per 1 mole of nickel metal in Raney nickel. You can choose.

The appropriate conditions under which to use a poisoned catalyst depend on the reaction conditions (reaction temperature, reaction pressure, amount of catalyst banded, etc.) when reducing DNS, depending on the conditions that are industrially advantageous. You can select and decide within the range.

Regarding the method of poisoning developed Raney nickel,
The amount of water used during poisoning, the method of adding acidic sulfites,
If the treatment temperature, treatment time, number of times of washing after treatment, etc. are kept constant, there will be no noticeable difference in the poisoning effect, so the reproducibility of the poisoning effect is high.

The relationship between the treatment conditions during poisoning and the degree of poisoning is as follows.

First, the amount of water used is related to the concentration of acidic sulfite, which is a poisoning agent, relative to the catalyst metal. However, the poisoning effect becomes thicker.

Any amount of water can be determined to suit the purpose of the present invention within an industrially manageable range.

The method of adding the acidic sulfite is, but is not limited to, adding the acidic sulfite as it is little by little or adding its concentrated aqueous solution to the aqueous suspension of the catalyst while stirring.

The temperature at which poisoning occurs is usually room temperature or under mild heating, e.g. 10°C.
Although it is carried out at a temperature of ~40°C, it is not necessarily limited thereto.

Washing with water after poisoning treatment is not performed when the reactor is poisoned by acidic sulfites.

Surprisingly, the poisoning effect of the poisoned catalyst does not actually decrease at all even after washing with recycled water, and even if the hydrogenation reaction is repeated with the same catalyst, the poisoning effect remains at least sufficient. Experiments have shown that it lasts for more than a few times.

The method of catalytically reducing DNS using a poisoned catalyst in the method of the present invention is as follows, but the method of the present invention is not limited to this method.

Pour the specified amount of poisoned Raney nickel catalyst aqueous paste and water into an autoclave equipped with a stirrer, close the lid, and
Replace the inside with hydrogen.

Alternatively, a predetermined amount of expanded Raney nickel paste, a portion of the water used for the reduction reaction, and a predetermined amount of acidic sulfite may be placed in an autoclave and the interior may be replaced with hydrogen.

The pressure and temperature are increased by 1 L· to, for example, 10 kg/rst and a gauge pressure of 80°C.

Next, while maintaining this pressure and temperature, catalytic reduction is performed while gradually pressurizing the DNS aqueous solution into the autoclave using a metering pump.

In this way, the reaction will proceed easily.

However, if the rate of DNS preparation is faster than the rate of conversion of DNS to DAS and a large amount of DNS remains in the reaction solution,
It is difficult for the reaction to proceed unless strict conditions are provided, so if you really want the reaction to proceed, you must conduct the reaction under strict conditions.

If the reaction is carried out under such conditions, the proportion of hydrogenation occurring in the ethylene bonds of stilbene will increase, making it impossible to obtain desired results.

(For example, according to Example 19 of JP-A-5012059, 15
During the main reduction, hydrogen is constantly replenished and the pressure is kept constant.

Immediately after DNS injection is completed, hydrogen absorption stops.

The autoclave is then cooled until the temperature of the contents is approximately 45.
When the temperature drops to ℃, stop stirring and reduce the pressure.

The catalyst is recovered by sedimentation and filtration and used for the next reduction.

The liquid from which the catalyst has been recovered and separated can be used as it is in the production of fluorescent whitening dyes using DAS as a raw material.

Further, by acidifying the mixture to precipitate DAS crystals and filtering it, a press cake can be obtained, which can also be used in the production of fluorescent whitening dyes and the like.

Even if catalytic reduction is carried out under similar conditions using an unpoisoned Raney nickel catalyst, the reaction proceeds.

However, in this case, a large amount of DABS is produced as a by-product, and a red color is also produced.

The details of the present invention will be explained below with reference to Examples, but the present invention is not limited thereto.

Example 1 Raney nickel4. Of (metal) and 100 ml of distilled water.
Weigh the amount of sodium sulfite (manufactured by Kanto Kagaku Co., Ltd.) and add it to a beaker with a stirring bar, while stirring.
00/Q was added little by little and stirred at room temperature for 30 minutes.

Thereafter, the supernatant water was discarded by tilting, 1001 liters of fresh water was added, and the mixture was stirred for 5 minutes.

I tilted it again and dumped the water. This operation was repeated three times.

Finally, wash off the catalyst attached to the stirrer, drain the water thoroughly by tilting it, put it in a 500ml stainless steel autoclave with a stirrer together with 100,771L of water, close the lid, replace it with hydrogen, and produce 2kg/crri. Pressure was applied to the gauge and the temperature was raised to 76° C. while stirring slowly.

When the temperature reached 76℃, increase the stirring speed and increase the internal pressure to 10kg/cr.
Using an RI gauge, autoclave 11.2% DNS (4,4'-sinitrostilbene 2,2' cisulfonic acid disodium salt) aqueous solution 941 using a metering pump at a constant flow rate for 65 minutes. Catalytic reduction was carried out while press-fitting the material.

During the reaction, the temperature was maintained at 76°C to 80°C, and the pressure was maintained at 9 to 10 kg/h while replenishing hydrogen according to hydrogen absorption.
I kept it at c♂ gauge.

After the injection of DNS was completed, the autoclave was kept at the same temperature as the reaction temperature for 12 minutes, then stirring was stopped, and the autoclave was cooled from the outside.

The pressure was reduced, the lid was opened, the contents were extracted, and the catalyst was separated.

As a result of analyzing the product liquid thus obtained by liquid chromatography, the content of DABS was 0.13%, and the rest was DAS.

According to diazotization analysis, the yield of DAS obtained by acid precipitation of the product solution was 98.0% versus theory.

Example 2 Raney Nickel 4.0'i! (metal), distilled water 100M
, sodium acid sulfite 250In9 proportions Example 1
The catalyst poisoned in the same manner as above was placed in the autoclave used in Example 1 along with 1001 liters of water, and the lid was closed.
After purging with hydrogen and pressurizing to 2 kg/crrt, stirring was started.
The temperature was raised to 7°C.

Catalytic reduction was performed while an 11.2% aqueous solution of DNS was injected into an autoclave using a metering pump (174 minutes) at a constant flow rate.

During the reaction, the temperature was maintained at 77°C to 79°C, and the pressure was increased to 9 to 10 ky/c4 while replenishing hydrogen according to hydrogen absorption.
I kept it on the gauge.

After the DNS pressure was completed, stirring was continued for 10 minutes at the same temperature, and then the autoclave was cooled from the outside to bring the contents to 45°C.

After reducing the pressure, the lid was opened, the contents were taken out, and the catalyst was separated.

Analysis of the raw liquid thus obtained by liquid chromatography revealed that the content of DABS was 0.83%, and the rest was D.
It was AS.

Example 3 Raney Nickel 4.0? (metal), distilled water 100ml,
A catalyst poisoned in the same manner as in Example 1 at a ratio of 500 μl of sodium acid sulfite was placed in an autoclave together with 1 QQ ml of water, and a DNS of 15.0 μl was added in the same manner as in Example 1.
Catalytic reduction was carried out while charging a 1512% aqueous solution for 128 minutes.

During the reaction, the temperature was maintained at 78 to 82° C., and the pressure was maintained at 6 to 7 kg/crA gauge without replenishing hydrogen according to hydrogen absorption.

After the completion of the preparation, stirring was continued for 10 minutes, and then the autoclave was cooled.

The analysis result of the produced liquid was 0.73% DABS and the rest was DAS.

Example 4 Raney nickel4. OS' (metal), distilled water 100ml
, acidic sodium sulfite} A catalyst poisoned in the same manner as in Example 1 at a ratio of 1,000 μl of sodium sulfite was placed in an autoclave with 100,771 liters of water and treated in the same manner as in Example 1.
Catalytic reduction was carried out while charging an 11.2% S aqueous solution 1041 for 90 minutes.

During the reaction, the temperature was maintained at 96 to 100°C, and the pressure was maintained at 9 to 10 kg/cw, with hydrogen being replenished according to hydrogen absorption.
I kept it on the gauge.

After the completion of the preparation, stirring was continued for 10 minutes, and then the autoclave was cooled.

The analysis result of the produced liquid was 80.55% DAB and the rest was DAS.

Example 5 Raney nickel 2.0P (metal), distilled water 100ml,
A catalyst poisoned in the same manner as in Example 1 with a proportion of 500 Iv of sodium acid sulfite was placed in an autoclave together with 100 rfLl of water, and 1v of DNS was added in the same manner as in Example 1.
Catalytic reduction was carried out while charging a 1.2% aqueous solution 1041 for 85 minutes.

During the reaction, the temperature was maintained at 119°C to 120°C, and the pressure was increased from 9 to IO kg/cr while replenishing hydrogen according to hydrogen absorption.
I kept it in A gauge.

After the preparation was completed, stirring was continued for 10 minutes, and then the autoclave was cooled.

The analysis result of raw liquid is DAB80.61%, the rest is DAS
Met.

Example 6 Raney nickel4. A catalyst poisoned in the same manner as in Example 1 with the proportions of Of (metal), distilled water 100 -, and acidic sodium sulfite 500 Iv was placed in an autoclave with 10 OrI'll of water and treated with DNS 11 in the same manner as in Example 1.
．． Catalytic reduction was carried out while charging a 2% aqueous solution of 104P for 7 minutes.

During the reaction, the temperature was maintained at 48° C. to 52° C., and the pressure was maintained at 2 to 3 kg/crA gauge without replenishing hydrogen according to hydrogen absorption.

After the completion of the preparation, stirring was continued for 10 minutes, and then the autoclave was cooled.

The analysis result of the product liquid was 0.60% DABS and the rest was DAS.

Example 7 Raney Nickel2. Of (metal), distilled water 100TLl
A catalyst poisoned in the same manner as in Example 1 at a ratio of 500 μl of sodium acid sulfite was placed in an autoclave with 100 ml of water, and the same method as in Example 1 was used to prepare 11.2 μl of DNS.
% aqueous solution 104. Catalytic reduction was carried out while charging P for 73 minutes.

During the reaction, the temperature was maintained at 78-80° C. and the pressure was maintained at 9-10 kg/crA gauge depending on hydrogen absorption.

After the completion of the preparation, stirring was continued for 10 minutes, and then the autoclave was cooled.

The analysis results of the raw liquid were 0.11% DABS and the rest was DAS.

Example 8 A catalyst poisoned in the same manner as in Example 1 with 4.0P (metal) of Raney nickel, 100 parts of distilled water, and 2000 m of sodium acid sulfite was placed in an autoclave together with 100,771 liters of water, and the same method as in Example 2 was carried out. and DNS 1
Catalytic reduction was carried out while charging a 1.2% aqueous solution 102i for 62 minutes.

During the reaction, the temperature was maintained at 97 to 100°C, and the pressure was maintained at 9 to 10 kg/cr while replenishing hydrogen according to hydrogen absorption.
I kept it in A gauge.

After the completion of the preparation, stirring was continued for 10 minutes, and then the autoclave was cooled.

The analysis result of the produced liquid was 80.01% DAB and the rest was DAS.

Example 9 Raney Nickel4. (1 (metal), 100ml of distilled water,
A catalyst poisoned in the same manner as in Example 1 with a proportion of 1000 In9 acidic ammonium sulfite was placed in an autoclave with 100 ml of water, and a 11.2% aqueous solution of DNS 1021 in the same manner as in Example 1 was added for 62 minutes. Contact reduction was performed during preparation.

During the reaction, the temperature was maintained at 79° C. to 80° C., and the pressure was maintained at 9 to 10 kg/c4 gauge without replenishing hydrogen according to hydrogen absorption.

After the completion of the preparation, stirring was continued for 10 minutes, and then the autoclave was cooled.

The analysis result of the raw liquid was 80.26% DAB and the rest was DAS.

Example 10 Put Raney nickel catalyst aqueous paste 4P (metal), 100 ml of water, and 1500 μl of acidic sodium sulfite into a 5001 rL autoclave equipped with a stirrer, close the lid, replace the hydrogen with hydrogen, raise the temperature to 76°C while stirring very slowly, and then reduce the hydrogen pressure. Use a 10 kg/cm gauge and speed up the stirring to 4.4'.
-Dinitrostilbene-2.2'-monodisulfonic acid 11
．． Catalytic reduction was carried out while charging 96 tons of a 2% aqueous solution over 60 minutes.

The temperature during the reaction was kept at 95-1. Maintain the temperature at 0.0°C and replenish the pressure according to the hydrogen absorption.9 to 10 kg.
/crtt gauge.

After the injection of DNS was completed, the autoclave was stirred at the same temperature for 10 minutes, the autoclave was cooled, the pressure was reduced, the lid was opened, the contents were extracted, and the catalyst was separated.

Analysis of the product liquid thus obtained by liquid chromatography revealed that the content of DABS was 0.25% and the rest was DAS.

Comparative Example 1 Raney nickel 0.5P (metal) was placed in a stainless steel 500 1111 autoclave equipped with a stirrer with 100 m#) water, the lid was closed, hydrogen was replaced, the pressure was increased to 2 kg/cvi gauge, and the temperature was heated to 77°C while stirring slowly. The temperature rose to .

When the temperature reaches 76°C, increase the stirring speed and reduce the internal pressure to OK.
/crA gauge, 11.2% DNS aqueous solution 102f
? Catalytic reduction was performed while pressurizing the sample into an autoclave using a metering pump at a constant flow rate for 90 minutes.

During the reaction, the temperature was maintained at 76°C to 78°C, and the pressure was maintained at 9 to 10 kg/cr while replenishing hydrogen according to hydrogen absorption.
j. I kept it on the gauge.

After the completion of the preparation, stirring was continued for 10 minutes, and then the autoclave was cooled.

The analysis result of the produced liquid was 83.13% DAB and the rest was DAS.
Met.

Comparative example 2 Raney nickel 4. o? (metal) with 100 ml of water into the autoclave used in Comparative Example 1, and in the same manner as Comparative Example 1, add 1 5 Cl of 11.2% aqueous solution of DNS to 10
Catalytic reduction was carried out during preparation for 0 minutes.

During the reaction, the reaction temperature was maintained at 76°C to 82°C, and the pressure was maintained at 9 to 10 kg/h while replenishing hydrogen according to hydrogen absorption.
The crA gauge was maintained.

After the completion of the preparation, stirring was continued for 16 minutes, and then the autoclave was cooled.

The analysis result of the produced liquid is DAB864.03% and the rest is DAS.
Met.

Comparative Example 3 Raney nickel 0.6r (metal) was placed in the autoclave used in Comparative Example 1 with 100 ml of water.
In the same manner as above, add 15M' of 11.2% aqueous solution of DNS to 90%
The catalytic reduction was carried out during preparation, which took several minutes.

During the reaction, the reaction temperature was maintained at 55°C to 61°C, and the pressure was maintained at 4 to 5 kg/cy depending on hydrogen absorption.
I kept it at yl gauge.

After the completion of the preparation, stirring was continued for 16 minutes, and then the autoclave was cooled.

The analysis result of the raw liquid was 32.10% DAB and the rest was DAS.

As mentioned above, when Raney nickel catalyst is used for catalytic reduction of DNS without treatment with acidic sulfite, more than half of DABS is produced as a by-product, especially when a large amount of catalyst is used.
It became ABS.

Claims (1)

[Claims] 1 Catalytic reduction of 4,4'-dinitrostilbene-2,2'-cisulfonic acid or its salt under hydrogen pressure in the presence of a Raney nickel catalyst poisoned with an acidic sulfite or an acidic sulfite and a Raney nickel catalyst. A method for producing 4,4'-diaminostilbene-2,2'-disulfonic acid or a salt thereof, characterized by: