CS235560B1 - Method of 1,3,5-trinitro-1,3,5-triazacyclohexane production - Google Patents

Description

The invention relates to a process for the preparation of 1,3,5-trinitro-1,3,5-trlazacyclohexane by nitrolysis of hexamethylenetetramine in nitric acid in the presence of dicyandiamide in the reaction mixture.

According to the most recent knowledge, the yield and safety of the nitrous cleavage and / or nitration process of amines or amides, respectively, to cyclic nitramines is favorably affected by the presence of urea, urea-formaldehyde condensates, amino-guanidine sulphate or tetrahydroiinidazo [4,5-d] imidazole-2,5 (1 H). dione in the respective reaction mixture (see, e.g., U.S. Patent Nos. 206,382, 213,509, 214,311 and others). The probable mechanism of multiplication of some of the above-mentioned additives has been discussed in several works, e.g. in MS. author's certificate no. 206 382; they are basically third generation catalysts.

According to the present invention, a process for the preparation of 1,3,5-trinitro-1,3,5-triazacyclohexane is carried out in nitrolysis of hexamethylenetetramine with fuming nitric acid in the presence of 0.01 to 15% by weight. % dicyandiamide, preferably in the presence of 0.2 to 14.1 wt. % of the dicyandiamide in the reaction mixture, calculated on the weight of the hexamethylenetetramine portion, wherein the dicyandiamide is added sequentially or simultaneously to the reaction system.

In particular, the advantage of the present invention is to increase the yield of the nitrolysis process, whereby this enabling additive is technically available. A less pronounced higher effect of the invention is to increase the stability of the nitrolysis mixture, which corresponds to an increase in the safety of the production process.

The higher effect achieved in the sense of the present invention has not been described in the literature so far; is illustrated by the following examples, which in no way exclude the possible variability of the production method according to the invention.

Example 1

Up to 710 parts by volume of 96.1% nitric acid with a content of 0.3% by weight. of analytical nitric acid, cooled to a temperature of 9 to 12 degrees Celsius, 100 wt. parts of hexamethylenetetramine to the reaction temperature in this operation was 14 to 17 ^C. After 25 min, the post-reaction at 17 to 19 ° C is nitrolyzačná was poured in a thin stream 3000 volume parts of 55-60 ° C water, the resulting suzpenzia after stirring for 30 minutes, the filter cake is washed 4X to 100 volume with portions of water. The crude 1,3,5-trinitro-1,3,5-triazacyclohexane is then dried for 3 hours. at 90 ° C.

The process is repeated using hexamethylenetetramine containing dicyandiamide; the results are summarized in Table no. First

Using a non-isothermal differential thermal analysis (DTA) operating at a linear temperature rise rate of 5 K. min ^-1 , measuring range of 1 mV per scale scale and weighing 80-90 mg of sample, determine the onset of the melting endotherm and the peak temperature of the melting endotherm (i.e. the onset of exothermic decomposition) by nitrolysis of the crude 1,3,5-trinitro-1,3, 5-triazacyklohexánu. The results are also summarized in Table. First

They are based on the principle of isothermal differential thermal analysis for zero-content and 0.7-pence nitrolysis mixtures. wt. of dicyandiamide to the weight of the weight of hexamethylenetetramine specified by the induction period of decomposition at 51.2 ± 0.6 ° C: in the reaction mixture without the additive, the exothermic decomposition begins after 2011 s, in the nitrolysis mixture with the additive after 2106 seconds.

Table 1

Overview of the results from Example 1

Quantity of dicyandiamide dosed Yields of 1,3,5-trinitro-1,3,5-triazacyclohexane DTA results beginning of melting endotherm ('C) melting endotherm peak (° C) wt. parts % wt. HMT wt. parts % versus theory 0.0 0.0 111.5 70.33 187.7 193.1 0.2 0.2 113.5 71.59 188.2 193.2 0.7 0.7 115.4 72.54 189.2 193.6 1.0 1.0 115.5 72.79 189.9 193.7 3.0 3.0 111.5 70.33 191.7 193.9

Note: HMT = hexamethylenetetramine '235 580

Example 2

Proceeding as in Example 1, only nitric acid is taken into the reaction in an amount of 1500 volumes, parts, and the reaction mixture is poured into 6400 volumes, parts of water. This procedure results in 109.4 wt. parts of 1,3,5-trinitro-1,3,5-triazacyclohexane, which is 69.0 percent yield from theory.

The process is repeated with 14.1 wt.% Dissolved in nitric acid at 8-10 ° C prior to the actual metering of hexamethylenetetramine. parts of dicyandiamide. 114.9 wt. parts of 1,3,5-trinitro-1,3,5-triazacyclohexane, which is 72.2 percent yield over theory.

By using DTA as in Example 1, an onset of nitrolysis product without additive found an onset of melting endotherm of 186.6 ° C and its peak at 191.9 ° C. In the same way, the onset of the reaction product in the presence of dicyandiamide is found to have an endotherm of melting at 189.7 ° C and its peak at 193.6 ° C.

Claims (1)

SUBJECT A process for the preparation of 1,3,5-trinitro-1,3,5-triazacyclohexane by nitrolysis of hexamethylenetetramine in nitric acid, characterized in that in the production process a gradual or simultaneously dicycane * diamide is added in an amount of 0.01 to 0.1 to the reaction system. 15% by weight, preferably in an amount of 0.2 to 14.1% by weight. to the weight of the hexamethylenetetramine.