SU689616A3 - Method of producing amide of aliphatic or aromatic monobasic carboxylic acid - Google Patents

Description

1. Copper powder or copper powder obtained by grinding copper ingots, small pieces or wire.

2. Restored copper, for example, is obtained by reducing a copper compound, such as copper oxide, copper hydroxide, copper chloride, etc., with the aid of hydrogen and / or carbon monoxide at a temperature from

About to 500 ° C;

3. Restored copper, for example, is obtained by reducing a copper compound, such as copper oxide, copper hydroxide, copper chloride (copper chloride), etc., using conventional reducing agents, such as hydrazine, sodium borohydride, etc., in the liquid phase .

4. Restored copper, for example, is obtained by treating a copper compound, such as copper oxide, copper hydroxide, copper chloride, etc., with a metal with a greater degree of ionization than copper, such as zinc, aluminum, iron, tin, and

so on, in the liquid phase.

5. Renee copper, for example, is obtained through the production of a Rene alloy containing copper and aluminum, zinc or magnesium.

6.Medium obtained, for example, by thermal cracking of a copper compound, for example, copper pseudo-acid or copper oxalate at a temperature of 100 to 400 ° C.

7.Mioelement catalyst, obtained, for example, by combining another metal, for example chromium, zinc, nickel, manganese or molybdenum, with one of these copper materials during the preparation of the catalyst.

3. Any of these catalysts on a substrate of inert material, such as alumina, silica, kieselguhr, pumice, diatomaceous earth, etc., obtained by depositing or depositing the catalyst on an inert substrate during the preparation of the catalyst.

One of the relevant methods for producing catalytic René copper is the René method, similar to the method for producing René nickel. Technical or commercial formulations of such catalysts are readily available, for example, an alloy of aluminum and copper. The catalysts are treated or activated by known methods and a copper metal catalyst is obtained that is suitable for use in the proposed method. Typically, such techniques include contacting an alloy with a strong base under conditions that leach aluminum or another metal.

The difference between these catalysts lies not so much in the selectivity of the reaction, as in their effectiveness. For example, when hydrating Acrylonitrile under normal conditions, with an appropriate selection of the catalyst and getting it extremely clean,

the reaction selectivity factor is 97% or more for acrylamide, and it is 2% or less for Eg.

The amount of metallic copper catalyst introduced by the proposed method is 0.01-1000 g per 1 mole of nitrile when used in a suspended layer. Such copper metal catalysts are suitable for use in both batch and continuous processes. In either method, the nitrile and water are contacted with the catalyst under the appropriate reaction conditions, after which the desired product, amide, is extracted.

It is advisable, as a rule, to expose the metallic copper catalyst to the reaction mixture in the liquid phase. It can also be exposed to the reaction mixture in the gaseous phase.

The ratio of nitrile and water in the reaction mixture can vary widely, as any amount of water is allowed, as long as it provides hydration. More important than the ratio of nitrile and water, is the degree of interaction between the reactants and the high degree of contact. With gaseous reactants, nitrile and water are mixed in all ratios. With liquid reagents, however, some measures that provide close contact between the nitrile and water, such as dissolving the nitrile in water or water in the nitrile, are useful. In addition to the limits of solubility of one reagent in another, the reaction mixture can be moved or a suitable compatible solvent can be added, or various other means can be used. Suitable inert compatible solvents include alkanols, for example, methanol, dioxane, dimethylsulfoxane, acetone, dimethyl ether, ethylene glycol, tetrahydrofuran, etc. The recommended ratio of nitrile and water is usually the ratio of water taken from excess to for example, water is 50-90 wt. % by weight of the reaction mixture.

The reaction temperature may vary widely, depending on the nitrile. The reaction is usually carried out at a temperature from 0 to. At a temperature below the specified interval, the reaction proceeds slowly, and at a temperature above the specified interval, the amount of reaction by-products formed increases. The preferred temperature range is 50-300 ° C. However, in reactions with a possible side reaction or polymerization, for example, in the conversion of acrylonitrile to acrplamide, the preferred temperature range is 50-150 ° C.

The resulting aqueous solutions amide derivatives contain trace amounts

used nitrates, and therefore they can be used directly as intermediates without the need for cleaning. Of course, any introduced ions can be removed if needed, for example, by using an ion exchange resin. Further, in the case where the target product is an aqueous solution of acrylamide, it can be directly used to obtain polymers suitable, for example, for use in papermaking or soil strengthening, as well as to obtain crystalline acrylamide. Similarly, in the case where the target product is nicotinamide, it can be effectively used as a material for the production of agricultural chemicals, as well as pharmaceutical preparations.

Another advantage of this method is the significant lengthening of the service life of the metallic copper catalyst during the production of the amide from the nitrile, so that any amide derivative can be obtained on an industrial scale, and in an effective manner.

More specifically, the corresponding combination of a copper metal catalyst and a nitrate promoter in accordance with the present invention, unlike the known combinations of a copper metal catalyst and a promoter in the form of a copper salt, greatly prevents the catalyst from deterioration or aging, as a result of which the consumption of copper can be reduced catalyst, thereby increasing the efficiency of the process.

The following examples illustrate, but do not limit the invention. In the examples, all parts are given in terms of weight, and all weight data imply dry weight, unless otherwise indicated. In all tables, the amount of promoter in rms is given in a weight ratio to the total weight of the liquid feed, including nitrile and water.

Example 1. On site, 150 g of Rene copper in a 1 liter reactor (made of stainless steel SUS-27) equipped with a stirrer and a catalyst separator are prepared in the usual way. Water and acrylonitrile, purified to 90% of the oxygen dissolved in them, by deoxidation

in a deoxidizing apparatus, fed to the reactor in a continuous process at a rate of 700 g / h and, respectively, 300 g / hr are brought into interaction at 120 ° C. Water contains 39 ppm of sodium nitrate, pre-made into it, which corresponds to 20 ppm of the promoter based on the total weight of the liquid raw material containing acrylonitrile and water. The reaction is carried out for 14 days and the reaction liquid is analyzed by the method of gas

chromatography; results are presented as acrylonitrile to acrylamide conversion ratio (Table 1) and conversion factors to impurities, especially acrylic acid, acrylate, ethylene cyainehydrin, and α-oxypropionamide, which together add up to 0.5% or even less. For comparison, the reaction and analyzes are repeated, but a known promoter, copper sulfate, in an amount of 10 ppm of copper ion by the total weight of the liquid raw material, instead of sodium nitrate, is taken as a promoter. The third reaction and analyzes are carried out without a promoter.

The results of the reactions and analyzes are presented in table. one.

Table I

Given in Table. 1, the results confirm the improved results obtained when using the sodium nitrate promoter as compared with the known promoter.

Example 2. The experiment described in Example 1 was repeated for 6 days, but instead of

The sodium nitrate promoter take various amounts of ammonium nitrate in an amount of from 4 to 1000 ppm by weight of the reaction liquid.

The results are shown in Table. 2, and the columns of the "no promoter" are taken from Table. one.

Example 3. The experiment of Example 1 was repeated for 6 days, replacing sodium nitrate with calcium nitrate, zinc nitrate and

Example 4. In a metal tube (reaction) with a volume of 300 cm, 300 g of tableted copper oxide are placed and the hydrogen, diluted with 2% nitrogen, is reduced to copper metal, passing at 200-250 ° C. Water and acrylonitrile, previously purified in 90% of the oxygen dissolved in them, are fed into the reaction tube continuously by passing through a deoxidizing apparatus at a speed of 700 g / h and 300 g / h, respectively.

Similar experiments were carried out using a catalyst obtained by reducing a copper salt with hydrazine, as well as a catalyst from copper oxide — chromium, which was subjected to reduction with the help of hydrogen.

The results are the same as in table. four.

Example 5. Into a reactor (stainless steel SUS-27) with a capacity of 10 liters, equipped with a stirrer and a catalysis separator. Table 2

iron nitrate in the amount of 20 ppm of the promoter in the reaction mixture.

The results are shown in Table. 3

Table 3

Conversion factor,%

the mixture c) in the reaction tube was introduced at 120 ° C. The incoming water initially contains 39 ppm of sodium nitrate, which corresponds to 20 prs of the promoter in the reaction mixture containing acryloyitrile and water.

The results of the reaction over the next 6 days are presented in table. 4. For the experiment, an additional experiment without sodium nitrate was carried out.

Table 4

Conversion factor,%

torus, placed 5 kg of powdered copper. Water and acrylonitrile, purified to 90% of the oxygen contained in the dissolved form, by passing through a deoxidizing apparatus, are fed into the reactor continuously at a rate of 700 and 300 g / hr, respectively, and are reacted at 120 ° C. Water contains 39 ppm of sodium nitrate, which corresponds to 20 ppm of the promoter in the reaction mixture containing acrylonitrile and water.

The results of the reaction are analyzed in the next 6 days; they are presented in table. 5. Conversion factors to impurities, especially to acrylic acid, acrylate, ethylene cyanohydrin and p-hydroxypropionamide Example 6. The experiment from Example 1 is repeated for 6 days, replacing acrylonitrile with methacrylonitrile and benzonitrile. Sodium nitrate was introduced in the amount provided by Example 7. The experiment of example 1 was repeated, replacing acrylonitrile with propionitrile and nicotinonitrile (i.e., 3-cyanopyridine). Sodium nitrate is charged at 0.5% or less. Additional experiments are carried out without the addition of sodium nitrate for comparison. The results are also shown in Table. five.

T a b l II c a .5

containing 20 ppm of the promoter in the reaction mixture. For comparison, the reaction is carried out without a promoter.

The results are presented in table. 6

Table 6

providing a content of 20 ppm in the reaction mixture. For comparison, the experiment was conducted without the addition of a promoter. The results are presented in table. 7

Claims (2)

Table 7 As can be seen from the above data, the degree of conversion of nitrile to amide increases to about 80%, and the activity of the catalyst with the proposed promoter decreases less in time than without the promoter or with a known promoter. Claims 1. A process for preparing an amide of an aliphatic or aromatic monobasic carboxylic acid hydration of nitrile selected from the group comprising acrylonitrile, methacrylonitrile, benzonitrile, propionitrile, nicotinonitrile, in the presence of a copper containing catalyst such as Raney copper, reduced copper and promoter katalnzatora - metal nitrate, wherein In order to increase the degree of conversion of nitrile to amide, 4-1000 ammonium, sodium, calcium, zinc or iron nitrate is used as metal nitrate RR per the reaction mass. 2. The method according to p. 1, from l and h and y i and so that the hydration is carried out at 50-300 ° C. Sources of information taken into account in the examination 1. US patent number 3361104, cl. 260-261, pub. 1971. 2. Japanese patent for application number 1724583 / / 23-04, cl. C 07C 102/08, with conv. priority from 14.12.70 (prototype).