CS209304B1 - Manufacturing process of 1,5-endomethylen-3,7-dinitroso-1,3,5,7-tetraazacyclooctane - Google Patents

Description

(54) A process for the preparation of 1,5-endomethylene-3,7-dinitroso-1,3,5,7-tetraazacolococtane. The present invention relates to a process for the preparation of 1,5-endomethylene-3,7-dinitroso-1,3,5,7-tetraazacyclooctane by nitrosation cleavage of hexamethylenetetramine with mineral acids. and sodium nitrite, whereby a higher yield is achieved by reducing the water content in the reaction mixture. mixtures.

Nitrosation cleavage of hexamethylenetetramine in weakly acid medium ?! is the most widespread method of industrial production of 1,5-endomethylene-3,7-dinitroso-1,3,5,7-tetraazaeyclooktane, also known as N, N-dinitrosopentamethylenetetramine, and referred to as DNPT. In this production process, hexamethylenetetramine in an aqueous medium is treated with a nitrosating agent which is nitrous oxide. From a technical and economic point of view, the most preferred source of nitrous oxide is nitrous acid, obtained by mineral acid from alkali metal nitrite or calcium nitrite.

The rate of major and desired cleavage reactions in the nitroslysis of hexamethylenetetramine, i.e. the rate of formation of N, 3f-dinitrosopentamethylenetetramine, is limited by the rate of nitrous oxide formation from nitrous acid in the sense of the equilibrium schenate (Ridd J .: Quart, Rev. 1961, 15, 418-441f Turney) A., Wright GA Chem Chem. 1959. 59. 497-513):

HN0 '- · .-- * ». N '0, + H' 0 '«<· ^{* 1 2} -..... 2 3 2

This equilibrium clearly shows the negative effect of water on the formation of the nitrosating agent.

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Nitric acid has no nitrosolysis properties (Fridman A. L. et al .: Uspeohl ohimii 1971, 40, 64-94) and provides complexes with hexamethylenetetramine by neutralizing reactions, respectively. ammonium compounds which produce formaldehyde and ammonium nitrite in aqueous media by subsequent hydrolytiocyanic reactions. Nitrous acid is characterized by such an oxidative effect on the organic compounds, in particular one of the byproducts of nitrosolysis of hexamethylenetetramine, which is formaldehyde.

From the above, it is apparent that as the water content of the nitrosation cleavage of hexamethylenetetramine increases, the reaction of the nitrosolysis reaction is suppressed and the reactions of neutralization and hydrolytiocoxidation are increased. '

The primary works from the preparation of 1,5-endomethylene-3,7-dinitroeo-1,3,5,7-tetraazaoyclooktane, still from the last century, were based on the initial water content of the reaction mixture, represented by at least 50 moles of water per 1 mole of hexamethylenetetramine. Later works are based on the molar ratio of water to hexamethylenetetramine usually 41 with 1 to 115: 1.

7.5 to 35 wt.%, With a conoentraoi branch of 20 to 30 wt.

When using a combination of an alkali metal nitrite or calcium nitrite and nitric acid 19 to 22%, the amount of water present together with the nitrite and hexame is used. tylentetramine, ranging from 41 to 43 moles per mole of hexamethylenetetramine (USSR Authorization Nos. 188 471, 189 980, 191 379, 191 380, 176 693 and 198 312), but also a method of displacing the molar ratio of water to hexamethylenetetramine is described. 59,5 ι 1 (Antoš K. et al. Chem. Rumors 1956, 10, 162), even with this ratio of 131.2: 1 (French Patent Specification No. 1,580,636).

When using a combination of hydrochloric acid and an alkali metal nitrite or calcium nitrite as the source of the disintegrating agent, the molar ratios of water to hexamethylenetetramine of at least 41: 1 (USSR Patent Nos. 189,980 and 188,471) are applied, further 53.2: 1 to 59.2 i) Japanese Patent Specification No. 20,068; Antoš K. et al .: Chem. rumors 1956, 10, 162), but also 115.8 (1).

004 618).

The application of sulfuric acid in the nitrosolysis process of hexamethylenetetramine is associated with the difficulty of dropping the inorganic by-product, which is sulfate decahydrate. sodium or potassium sulfate, from the reaction mixture together with s, ϊΤ-dihitrosopentamethylenetetramine. Therefore, many authors prefer the molar ratio of water to hexamethylenetetramine such that the inorganic by-product remains dissolved in the mother liquor, at least 72 moles of water per mole of hexamethylenetetramine (Japanese Patent No. 21,533; Japan. Kokai 76 80,898; Bdurjol G. However, an initial molar ratio to hexamethylenetetramine of 59.5: 1 was used (Antoš K. et al .: Chem. Rumors 1956, 10, 162). However, a process for the production of N, N-dinitrosopentamethylenetetramine using sulfuric acid (CSSR Authentication No. 189 214) is described, starting from a molar ratio of water to hexamethylenetetramine of 38.4% and above; however, together with the product from the reaction mixture, at least 96% of all sodium decahydrate falls out and the isolation of the main product then necessarily requires additional equipment and thermal and electrical energy consumption.

For conducting nitroeolysis of hexaraethylenetetramine in a weakly acidic environment with reduced water content below the preferred molar ratio of water to hexaraethylenetetramine of 41: 1, the combination of nitric acid and alkali metal nitrite or calcium nitrite as the source of the nitrosating agent is most preferred. In view of the solubility of the inorganic by-product, hydrochloric acid is also acceptable for displacing nitrous acid from said nitrite.

SUMMARY OF THE INVENTION The present invention provides a process for the preparation of 1,5-enaomethylene-3,7-dinitroso-1,3,5,7-tetraazaeyclooctane by nitrosation of hexamethylenetetrarain with nitric or hydrochloric acid and sodium nitrite, wherein the molar ratio of water in the reaction mixture to hexamethylenetetrarain is 17 µl to 41: 1, preferably at least 17.14: 1.

Reducing the water content of the nitrosolysis mixture will increase the unit volume yield of the mixture and reduce the volume of the mother liquor that remains (important in terms of further processing of this waste - energy savings may occur).

Smaller amounts of water in the nitrosolysis of hexamethylenetetramine may also lead to an increase in the yield of 1,5-endomethylene-3,7-dinitroso-1,3,5,7-tetraazaoyklooktanuf, but there are also major macro-kinetic factors (see CSSR author's certificate No. 182 625): An increase in product yield over theory is real when the process is conducted in such a way that the inlet of mineral acid is carried out into the stirrer compartment (ie below the level of the mixture) at a temperature below 12 ° C and agitating to such an extent that and the remainder (most) held at the level of the reaction mixture.

The higher effect of the processes for producing the 1,5-endomethylene-3,7-dinitroso-1,3,5,7-tetraazaoyclooctane of the present invention has not been reported in the literature and is documented by the following examples:

Example 1

To a 750 ml sulfonation flask equipped with a mercury, mercury thermometer and jacket cooling was added 28 g of hexamethylenetetramine (0.200 mol) as an aqueous solution of a certain concentration (presented below in the tabular overview) and 112 ml of sodium nitrite containing 339 g of substance / v liter (i.e. 0.549 mol of sodium nitrite). After cooling the solution to 5-6 ° C, a 20.16% nitric acid inlet (132 mL, 0.472 mol) was started with stirring so that the temperature of the mixture did not exceed 10 ° C (cooled) and the total acid inlet time was 9 to 12 minutes. After the acid was supplied, the reaction was carried out for 15 minutes at 10-14 ° C. Then the product was isolated by filtration, the acidic filter cake was washed with 50 ml of cold water, then with 50 ml of ca 0.1% aqueous ammonia and twice with 50 ml of cold water. After drying at a temperature of 30-38 ° C (for 42 hours), the product quality was specified by differential thermal analysis (DTA), weighing about 0.1 sample and a temperature rise rate of 6 ° C per minute. Using the DTA in this embodiment, the content of the by-product of the reaction, i.e. 1,3,5-trinitroso-1,3,5-triazaoyclohexane (R-salts), was determined and the product was thermally decomposed. The results are presented in a tabular overview.

Example 2 /

550 liters of a 3 ° C cooled solution of hexamethylenetetramine containing 380 g of substance per liter (1.49 kmol of hexamethylenetetramine) and 625 liters were charged to a process nitrosator equipped with agitation, snake reporting and bottom outlet. also to a temperature of 3 ° 0 of a chilled sodium nitrite solution containing 450 g of substance (4.07 kmol of sodium nitrite submitted) and 132 g of sodium nitrate per liter (0.97 kmol of sodium nitrate)} roztooíoh was 850 liters, that is 47.20 kmol. Stirring and cooling were initiated with an inflow of 20.8% nitric acid in an amount of 1060 liters (3.5 ° kmol of nitric acid) so that the temperature of the mixture did not exceed 12 ° C. Stirring was performed at a rate such that the excreted product was kept at the mixture level by the gaseous products of the reaction. After delivery

Tabular survey of results for example ls

.Concentration Mol. Yields water ratio product flow water to HMT (%) % (w / w).

47.36 17,148 78.18 37.50 38,760 78.92 31.03 43.083 79.01 26.47 47,407 78.17 15.25 69,024 ' 72.32

Results I) TA

Počátek 9X0- term.iokého decomposition (° C) Content of R-salt in the product 133.1-0.3 0.38% 129.7 * 0.9 0.31% 127.8 * 1.2 0.33% 127.3 * 0.1 0.85% 124.3 * 0.9 1,23%

Notes: HM «hexaaethylenetetramine

The R-salt of 1,3,5-trinitroso-1,3,5-triazaoyclohexane acid and a 15 minute reaction at 11-14 ° C were isolated by filtration, the filter cake was stirred in 1500 liters and 0.2% - of aqueous sodium hydroxide solution and the resulting suspension was then processed on an automatic pressure filter. 270 kg of a product containing 6.1 wt. Thus, the yield, calculated as dry matter, is 91.95% of theory.

EXAMPLE 3 Lithosolysis of a solution of hexamethylenetetramine taken in the same quantity and quality as in Example 2 was carried out under the same reaction conditions as in Example 2, except that 850 liters of sodium nitrite solution containing 330 g of substance and 10 g of nitrate sodium per liter (4.06 kmol sodium nitrite and 0.01 kmol sodium nitrate). The total amount of water in the solution mixture was 1100 liters, i.e. 61.05 kmol of water. The yield was 260 kg of product containing 7.2 wt. water, which is 87.1% of theory, calculated on the dry matter.

Example 4

630 liters of a solution of hexamethylenetetramine containing 330 g of substance per liter (1.48 kmol of hexamethylenetetramine in total) was charged to the process nitrosator as in Example 2. The indicated amount of solution represented 26.22 kmol.wateri A sodium nitrite solution was applied in the same quantity and quality, as in Example 3. Reakoe was conducted in the same manner as in Example 2, but with an initial total amount of water in the present solutions of 1185 liters (65.82 kmol of water). 255 kg of a product having a content of 7.57 wt. water, about 85.8% of theory, calculated on dry weight basis.

Example 5

In a 30 liter nitrosator equipped with jacket cooling and stirring and variable speed, 2000 g of hexamethylenetetramine (14.266 mol) was dissolved in the present 10 466 ml of a technical sodium nitrite solution containing 2570 g of substance (37.241 mol of sodium nitrite), 1000 g of sodium nitrate (11.763 mol) and 9000 ml of water (499.556 mol of water). The solution was cooled to -15 ° C and 2800 ml of 37.27% hydrochloric acid (33-908 moles of hydrogen chloride) were added in one portion while vigorously stirring and vigorously cooling the solid carbon dioxide-methanol mixture. The method of smoothing the reaction mixture ensured that its temperature at the inlet of the acid did not exceed 5 ° C. A 10 minute post-reaction at 5 to 8 ° C was carried out with vigorous agitation. The product was isolated by filtration, washed twice with 1000 ml of water and then with 1000 ml of 0.5% aqueous ammonia and finally twice with 1000 ml of water. After drying, 1460 g of N, N-dinitroso-pentamethylenetetramine resulted in 55.3% of theory.

EXAMPLE 6 Lithosolysis of hexamethylenetetramine was conducted as in Example 5 above, except that 9730 ml of a solution of pure sodium nitrite containing 2580 g of substance (37.386 mol of sodium nitrite) and 9000 ml of water (499.556 mol of water) were applied. The reaction resulted in 1160 g of product, which is 43.9% of theory.

Example 7

Nitroeolysis of hexaraethylenetetramine was conducted as in Example 5, but for dissolution, this substance was applied with a solution of teohnlocal sodium nitrite containing 2570 g of nitrite (37.241 mol of sodium nitrite), 1000 g of sodium nitrate (11.763 mol of sodium nitrate) and 11,000 ml of water (610.568) mol of water). The reaction resulted in 1460 g of product, which is 55.3% of theory.

Example 8

The nitrosolysis of hexamethylenetetramine was conducted as in Example 5 except that the addition of the hydrochloric acid was below the reaction mixture level in the space of the agitator for 9 to 12 minutes; The reaction was carried out with an intensity such that most of the excreted product during the reaction was kept at the level of the reaction mixture by the gaseous reaction products. By cooling, the temperature of the introsolysis mixture was maintained from 4 to 9 ° C from the outset. 2245 g of product resulted, which is 85% of theory.

Example 9

The nitrosolysis of hexamethylenetetramine was conducted as in Example 7, but under the reaction conditions of Example 8. 2210 g of product resulted, resulting in 83.7% of theory.

Claims (1)

OBJECT OF THE INVENTION A process for the preparation of 1,5-eademethylene-3,7-dinitroso-1,3,5,7-tetraazaeyclooctane nitroeate by resolving hexamethylenetetramine with nitric acid or hydrochloric acid and sodium nitrite, wherein the sodium nitrite optionally contains up to 1 mol of sodium nitrate per mole of hexamethylenetetramine, wherein the mole ratio of water in the reaction mixture to hexamethylenetetramine is 17 to 1: 41: 1, preferably at least 17.14 mole of water to hexamethylenetetramine is used. 1.