JPH07165662A - Production of glyoxal - Google Patents

Abstract

PURPOSE:To obtain glyoxal useful as a fiber-processing agent, a soil-processing agent, etc., in a long catalyst life, a high selectivity and a high yield by subjecting ethylene glycol to an oxidative dehydrogenation reaction in the presence of a specific catalyst at a specified temperature. CONSTITUTION:Ethylene glycol is oxidatively dehydrogenated in the presence of an element of Pb, Bi, Sn, Sb or one of their compounds and Ag as catalysts at a reaction temperature of 500-700 deg.C to obtain the objective compound. Preferably, the ethylene glycol is oxidatively dehydrogenated in the coexistence of P (compound) in an amount of 0.01-5.0ppm as P on the basis of the ethylene glycol.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel method for producing glyoxal. Specifically, it relates to a method for producing glyoxal.

[0002]

2. Description of the Related Art Various proposals have been made for a method for producing glyoxal, which is a very useful compound as a fiber processing agent, paper processing agent, soil curing agent, and other organic synthetic intermediate by oxidative dehydrogenation of ethylene glycol. is there. For example, a method of performing oxidation in the presence of silver crystals having a constant particle size (0.1 to 2.5 mm) (Japanese Patent Publication No. 61-54011) and a method of contact oxidation with silver crystals in the presence of a vaporizing phosphorus compound ( Tokoku 2
-49292) and the like have also been proposed.

A method for producing a dialdehyde using a silver catalyst supported on a carrier has also been proposed. For example, Izv.
Akad.Nauk.SSSR, Ser.Khim.641 to 643 (1964) uses an alumina-supported silver catalyst (Ag-supported amount 32%) at a reaction temperature of 60.
Although the reaction is carried out at 0 ° C., the yield is 20% and the space-time yield is 23.
Only low results of 8kg-GX / m ³ -cat ・ Hr have been obtained. Further, although there are JP-A-57-203024 and the like, there are drawbacks such as the use of diluted ethylene glycol and a large amount of unreacted ethylene glycol. Thus, a method for producing dialdehyde by oxidative dehydrogenation of ethylene glycol in the presence of a copper catalyst or a silver catalyst is known.

[0004]

SUMMARY OF THE INVENTION For example, a fiber processing agent,
When glyoxal is used as a paper processing agent, it is not preferable because a large amount of impurities such as glycolaldehyde causes a problem such as yellowing, which is not preferable. It is difficult to separate and remove unreacted ethylene glycol in the product glyoxal aqueous solution and glycol aldehyde as a reaction intermediate.Therefore, no raw material ethylene glycol remains in the oxidative dehydrogenation reaction step and glycol aldehyde as a reaction intermediate is produced. You need not to. Therefore, it is necessary to select a strict manufacturing condition and an appropriate catalyst, and conventionally, the yield was sacrificed to reduce impurities.

[0005]

The inventors of the present invention have completed the present invention as a result of extensive studies in order to overcome the drawbacks of the conventional method in the method for producing glyoxal by vapor-phase oxidation of ethylene glycol. is there. That is, in the method for producing glyoxal of the present invention, a reaction temperature of 500 to 700 is used with a catalyst containing silver as a main component and one or more elements or compounds of lead, bismuth, tin and antimony added thereto.
It is characterized by oxidatively dehydrogenating ethylene glycol at ℃. In the catalyst of the present invention, 0.1 to 10 wt% of at least one element or compound selected from lead, bismuth, tin and antimony can be added to silver as an element. Oxidative dehydrogenation of ethylene glycol at a reaction temperature of 500 to 700 ° C. using as a catalyst at least 50 wt% of one or more elements or compounds of silver, lead, bismuth, tin and antimony supported on a carrier. Is characterized by. Further, as phosphorus relative to ethylene glycol, 0.01-5.
This is characterized in that the oxidative dehydrogenation reaction of ethylene glycol is carried out in the presence of 0 ppm of a phosphorus compound.

In the silver catalyst used in the method of the present invention, one or more elements or compounds of lead, bismuth, tin and antimony are added to silver, and an additive metal such as lead, bismuth, tin and antimony is added together with silver. It is possible to use a material obtained by melting and solidifying the melt to form a wire or shavings, or a granular material obtained by spray quenching the melt.
In addition, ordinary silver particles and silver-supported catalysts are impregnated with lead, bismuth, tin, antimony compounds, for example, an aqueous nitrate solution,
It is possible to use a product which is dried and calcined, and reduced if necessary.

In the present invention, pure oxygen or air may be used as the molecular oxygen, but the latter is economically preferable. Further, in order to obtain glyoxal in a high yield, ethylene glycol and molecular oxygen are diluted with an inert gas to carry out the reaction. As the inert gas, a rare gas such as nitrogen, helium or argon, carbon dioxide gas or water vapor is used.

The gas phase oxidation according to the method of the present invention has a reaction temperature of 5
A temperature of 00 to 700 ° C., preferably 550 to 640 ° C. is suitable. Unreacted ethylene glycol and glycol aldehyde increase in the reaction at temperatures lower than 500 ° C.
The reaction at a temperature higher than 0 ° C. is not preferable because the amount of formalin, carbon monoxide and carbon dioxide is increased and the amount of glyoxal is reduced.

In the present invention, the phosphorus compound may be preliminarily mixed with ethylene glycol in a predetermined amount to participate in the reaction, or may be added alone or as a solution to the reaction system separately from ethylene glycol. As the phosphorus compound, first to third phosphine such as mono, di or trimethylphosphine, methyl phosphite, ethyl phosphite,
Various organic phosphorus compounds such as phosphorous acid ester methylphosphonic acid dimethyl ester and ethylphosphonic acid diethyl ester can be effectively used.

However, the phosphorus compound having a high boiling point requires the evaporator temperature to be particularly high, or the phosphorus compound stays in the evaporator and decomposes and accumulates to cause corrosion of the equipment material. The generated iron rust or the like may fly to the reaction layer and adversely affect the reaction, which is not preferable. Therefore, a relatively low boiling point organophosphorus compound,
For example, methyl phosphite, ethyl phosphite, methyl phosphate, ethyl phosphate and the like are more preferably used.

The amount of phosphorus or phosphorus compound added is 0.01-5.
A range of 0 ppm is suitable. The addition of the phosphorus compound significantly suppresses the formation of oxidation products such as carbon monoxide and carbon dioxide and decomposition products such as formaldehyde, as compared with the case where these compounds are not added, and thus the target product glyoxal The yield rate is significantly improved.

[0012]

EXAMPLES The present invention will now be specifically described by way of examples, but the present invention is not limited to these examples.

Comparative Example 1 Silver particles 1.0 to 0.25 mm obtained by the electrolysis method
gr, 0.25 to 0.17 mm is 5 gr, 0.17 to 0.10.
1.5 mm was charged from below into a stainless steel reactor having an inner diameter of 27.4 mm. 150g / Hr of ethylene glycol and 1 steam of steam through this reactor through an evaporator and a preheater
50 g / Hr, 300 liters / hr of air and 590 liters / hr of nitrogen were supplied in a downward flow to react at a reaction temperature of 570 ° C.

Two days after the start of the reaction, the reaction gas was cooled and the product was separated and collected in a water absorption tower. This result shows that the ethylene glycol conversion is 99.7% and the glyoxal selectivity is 4
The selectivity was 6.5%, the selectivity for formalin was 10.8%, and the selectivity for glycolaldehyde was 0.48%.

Further, ethylene glycol 150 g / hr, steam 150 g / hr, air 300 liters / hr and nitrogen 560 liters / hr through the evaporator and preheater in the reactor, ethylene glycol was added with 3 ppm of trimethyl phosphite as phosphorus. The reaction was continued at a reaction temperature of 570 ° C. by adding and feeding in a downward flow. Four days after the start of the reaction, the analysis results of the collected liquid were that the ethylene glycol addition rate was 99.4%, the glyoxal selectivity was 59.5%, the formalin selectivity was 7.6%, and the glycol aldehyde selectivity was 0.87%.

Example 1 100 gr of silver particles having a particle size of 1.0 to 0.07 mm obtained by the electrolysis method was dipped and dried in an aqueous lead nitrate solution corresponding to 1 wt% with respect to silver, and further dried at 480 ° C. Heated for 10 minutes. Particles obtained by crushing and classifying after cooling 1.0-0.25 mm
10 gr, 0.25 to 0.17 mm to 5 gr, 0.17 to
2 gr of 0.10 mm was charged from below into a stainless steel reactor having an inner diameter of 27.4 mm.

150 g / Hr of ethylene glycol, 150 g / Hr of steam, 300 liters / hr of air and 600 liters / hr of nitrogen were fed to the reactor through an evaporator and a preheater at a reaction temperature of 570 ° C. It was made to react. Two days after the start of the reaction, the reaction gas was cooled and the product was separated and collected in a water absorption tower. This result shows that the ethylene glycol conversion is 9
9.9%, glyoxal selectivity 44.5%, formalin selectivity 10.7%, glycol aldehyde selectivity 0.
It was 18%.

Furthermore, ethylene glycol 150 g / hr, steam 150 g / hr, air 300 liter / hr and nitrogen 570 liter / hr were passed through the evaporator and preheater in the reactor, and 3 ppm of trimethyl phosphite as phosphorus was added to ethylene glycol. The reaction was continued at a reaction temperature of 570 ° C. by adding and feeding in a downward flow. Four days after the start of the reaction, the analysis results of the collected liquid were that the ethylene glycol addition rate was 99.8%, glyoxal selectivity was 59.2%, formalin selectivity was 7.6%, and glycolaldehyde selectivity was 0.28%.

Comparative Example 2 A specific surface area of 0.29 m ² / g and 250 to 150 μm of 25
wt%, 150-105 μm 42 wt%, 105-75 μm
50 gr of a silver nitrate solution (200 gr of silver nitrate + 100 gr of water) was impregnated and mixed into 100 gr of silica having various particle sizes of 33 wt% of m 3 and dried at 100 ° C. while mixing. The dried powder was heat-treated in the air at 600 ° C. for 30 minutes, cooled, and pulverized. Further, the same impregnation, drying, heat treatment and pulverization were repeated several times to prepare a catalyst having a silver supported amount of 68 wt%. Inner diameter 27,4
mm to stainless steel reactor 250-150μ
m is 10 gr, 150 to 105 μm is 10 gr, 105 to 7
5 μm was packed with 5 gr of catalyst of various particle sizes.

136 g / Hr of ethylene glycol and 136 g / Hr of steam were passed through this reactor through an evaporator and a preheater.
Air 270 liters / Hr and nitrogen 510 liters /
The reaction was carried out at a reaction temperature of 630 ° C. by supplying Hr downward flow. One day after the start of the reaction, the reaction gas was cooled and the product was separated and collected in a water absorption tower.

This result shows that the ethylene glycol conversion rate is 9
9.7%, glyoxal selectivity 47.6%, formalin selectivity 10.2%, glycol aldehyde selectivity 0.
It was 31%. Furthermore, 2 ppm of triethyl phosphite was added as phosphorus, and the reaction was continued at a reaction temperature of 620 ° C. Three days after the start of the reaction, the results were that the ethylene glycol conversion was 99.5%, glyoxal selectivity was 60.1%, formalin selectivity was 12.4%, and glycolaldehyde selectivity was 0.35%.

Example 2 The silver-supported catalyst prepared in Comparative Example 2 was suspended in an aqueous bismuth nitrate solution, neutralized and hydrolyzed with an aqueous NaOH solution, filtered, washed with water and dried to give 0.5 wt% of bismuth with respect to silver. A catalyst containing was prepared.

This silver-bismuth catalyst was placed in a stainless steel reactor having an inner diameter of 27.4 mm with 250 to 150 μm of 10 gr, 150 to 105 μm of 10 gr, and 105 to 75 μm.
m was charged with 5 gr of catalyst of various particle sizes.

136 g / Hr of ethylene glycol and 136 g / Hr of steam were passed through this reactor through an evaporator and a preheater.
Air 270 liters / Hr and nitrogen 510 liters /
The reaction was carried out at a reaction temperature of 630 ° C. by supplying Hr downward flow. One day after the start of the reaction, the reaction gas was cooled and the product was separated and collected in a water absorption tower.

This result shows that the ethylene glycol conversion rate is 9
9.8%, glyoxal selectivity 45.9%, formalin selectivity 9.8%, glycol aldehyde selectivity 0.2
It was 2%. Furthermore, 2 ppm of triethyl phosphite was added as phosphorus, and the reaction was continued at a reaction temperature of 620 ° C.
3 days after the start of the reaction, the result was an ethylene glycol conversion rate of 9
9.8%, glyoxal selectivity 57.3%, formalin selectivity 10.4%, glycol aldehyde selectivity 0.
It was 25%.

Example 3 The silver-supported catalyst prepared in Comparative Example 2 was suspended in an aqueous solution of antimony chloride corresponding to 1 wt% of antimony with respect to silver, neutralized and hydrolyzed with an aqueous solution of NaOH, filtered, washed with water and dried. Thus, an antimony-containing silver-supported catalyst was prepared. This silver-antimony catalyst was placed in a stainless steel reactor having an inner diameter of 27.4 mm and 250 to 150 μm of 10 gr and 150 to 150 μm.
10 μg of 105 μm and 5 gr of 105-75 μm were charged with catalysts of various particle sizes.

136 g / Hr of ethylene glycol and 136 g / Hr of steam were passed through this reactor through an evaporator and a preheater.
Air 270 liters / Hr and nitrogen 510 liters /
Add 2ppm triethyl phosphite as Hr and phosphorus,
The reaction was carried out at a reaction temperature of 600 ° C. by feeding in a downward flow.
One day after the start of the reaction, the reaction gas was cooled and the product was separated and collected in a water absorption tower.

This result shows that the ethylene glycol conversion rate is 9
9.8%, glyoxal selectivity 56.9%, formalin selectivity 10.3%, glycol aldehyde selectivity 0.
It was 23%.

Example 4 100 gr of silver particles having a particle size of 1.0 to 0.07 mm obtained by the electrolysis method was immersed in an aqueous solution of stannous chloride corresponding to 2 wt% of silver, and neutralized with aqueous ammonia. Post filtration, washing with water, and drying were performed. 10 g of the obtained particles 1.0 to 0.25 mm,
0.25 to 0.17 mm of 5 gr and 0.17 to 0.10 mm of 2 gr were charged from below into a stainless steel reactor having an inner diameter of 27.4 mm.

125 g / Hr of ethylene glycol, 125 g / Hr of steam, 240 liters / hr of air and 500 liters / hr of nitrogen were added to this reactor through an evaporator and a preheater, and 2 ppm of trimethyl phosphite as phosphorus was added to ethylene glycol. The syrup was fed in a downward flow to react at a reaction temperature of 590 ° C.

One day after the start of the reaction, the reaction gas was cooled and the products were separated and collected in a water absorption tower. This result shows that the ethylene glycol conversion is 99.9% and the glyoxal selectivity is 5
The selectivity was 8.5%, the selectivity for formalin was 8.7%, and the selectivity for glycolaldehyde was 0.27%.

[0032]

According to the method of the present invention, in the production of glyoxal from ethylene glycol, unreacted ethylene glycol and glycol aldehyde, which is a reaction intermediate, are less likely to be produced, and the catalyst life can be maintained for a long period of time. The conversion rate and the selectivity of glyoxal can be secured, the production of by-products can be suppressed, and glyoxal can be produced in a high yield, which is extremely advantageous to the industry.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hatsuo Inoue 1-6 Takasago, Takaishi-shi, Osaka Mitsui Toatsu Chemical Co., Ltd. (72) Masato Yamazaki 1-6 Takasago, Takaishi-shi, Osaka Mitsui Toatsu Inside Chemical Co., Ltd.

Claims (4)

[Claims] 1. A reaction temperature of 50 using at least one element or compound of lead, bismuth, tin and antimony and silver as a catalyst.
A method for producing glyoxal, which comprises oxidatively dehydrogenating ethylene glycol at 0 to 700 ° C. 2. The method for producing glyoxal according to claim 1, wherein one or more elements or compounds of lead, bismuth, tin and antimony are added as a 0.1 to 10 wt% element with respect to silver as a catalyst. . 3. At least 50 wt% of at least one element or compound of lead, bismuth, tin and antimony and silver as a carrier.
The method for producing glyoxal according to claim 1, wherein the supported one is a catalyst. 4. The method for producing glyoxal according to claim 1, wherein the ethylene glycol is oxidatively dehydrogenated in the presence of 0.01 to 5.0 ppm of phosphorus or a phosphorus compound as ethylene glycol.