JPH11322752A - Crystallization of epsilon-hexanitrohexaazaisowurzitane using seed crystal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process for producing a thermodynamically stable ε- hexanitrohexaazaisowurzitane (HNIW) having a high density in a short time in a high yield. SOLUTION: This process for the production of ε- hexanitrohexaazaisowurzitane comprises the dissolution of HNIW in a mixture of a good solvent and a poor solvent, addition of ε-hexanitrohexaazaisowurzitane as a seed crystal and the evaporation of the good solvent to precipitate the crystal. The amount of ε-hexanitrohexaazaisowurzitane to be added as the seed crystal is 0.1-10%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for producing a low-sensitivity .epsilon.-hexanitrohexaazaisowurtzitane crystal, which is used for improving the performance of a conventional explosive composition, by using a seed crystal in an amount of 90% or more. It relates to a manufacturing method for manufacturing with purity.

[0002]

2. Description of the Related Art Hexanitrohexaazaisosoultitanium (hereinafter referred to as "HNIW") is a high-density and high-energy substance, and is regarded as a promising next-generation high explosive material. HNIW has a plurality of crystal forms, and the existence of at least α-HNIW, β-HNIW, γ-HNIW, and ε-HNIW has been confirmed. Among them, ε-H
Since NIW has a high density and is in a thermodynamically stable state, NIW is a crystal form that has received the most attention as an explosive material. Α-HNIW, β-HNIW, or γ-HNIW is known as a metastable crystal.

Regarding the conversion of a crystal, the following contents are known. There is a report that ε-HNIW could not be obtained from α-HNIW dehydrated with ε-HNIW as seed crystals [Propellants, E
xlossives, Pyrotechnics19,
19-25 (1994)]. However, no specific conditions are described. Further, α-HNIW, β-HNIW, or a mixture of γ-HNIW and ε-HNIW is mixed in a solvent such as xylene, xylene to which 10 to 30% acetophenone is added, bis (2-fluoro-2,2-dinitroethyl) formal, or the like. There is a report that it is converted to ε-HNIW.

Further, γ-HNIW and ε-HN in a solution state
It has been reported that a mixture of IW is recrystallized to ε-HNIW below 64 ° C. Also, γ-HNIW and ε-HN
Conversion of the mixture of IW to ε-HNIW can be achieved by adding a solvent such as ketones having high solubility to HNIW.
There is a report that equilibrium occurs within hours [Propell
Ants, Explosives, Pyrotechn
ics19, 19-25 (1994); Propell
Ants, Explosives, Pyrotechn
ics 19, 63-69 (1994); Propell
Ants, Explosives, Pyrotechn
ics 19, 206-212 (1994)].

However, none of these documents describes specific conditions such as the ratio of HNIW to a solvent. Α-HNIW and ε-HNIW are used in a mixture of α-HNIW and α-HNIW.
When the content of W is increased, α-HNIW may remain even when a large amount of xylene is used. α-HNIW hydrate is 64
It has been reported that the temperature is converted to ε-HNIW below ℃ [P
ropellants, Explosives, Pyr
otechnics 19, 19-25 (1994)].
There is also a report that ε-HNIW was obtained by a two-solvent crystallization method [Int. Annu. Conf. ICT (1
996), 27th (Energy Material)
ials), 27.1-27.10].

There is also a report that ε-HNIW has been obtained. [Int. Annu. Conf. ICT (199
6), 27th (Energy Material)
ls), 39.1-39.12; Int. Annu. C
onf. ICT (1996), 27th (Energy
tic Materials), 23.1-23.1.
3; Chin. Sci. Bull. (1996), 41
(7), 574-576; Proc. Beijing
Int. Symp. Explos. , 3rd (199
5) 520-525; Proc. Beijing I
nt. Symp. Explos. , 3rd (199
5), 312-314; Proc. INT. Pyrot
ech. Semin. (1996), 22nd, 425
-432].

[0007] However, these are all specific ε-H
No description is given of NIW conversion conditions. Also, α
A method for obtaining β-HNIW and a method for obtaining β-HNIW have been reported [U. S Patent 5,693,7
94 (1988)]. However, the conversion of ε-HNIW is not described at all.

[0008]

The HNIW is, for example, WO
It is manufactured by the method described in JP-A-98-05666. In these methods, HNIW is often obtained from a crystal containing meta-stable crystal α-HNIW or β-HNIW of 90% or more, and further converted to ε-HNIW to obtain ε-HNIW. Need to be performed. The crystal precipitation method using a seed crystal can grow a crystal even from a low supersaturation state, and can precipitate a crystal more easily than a case where no seed crystal is used.
The seed crystal referred to here is a small crystal serving as a nucleus for crystal growth. It is widely known that seed crystals and a solvent in which the target substance is not easily dissolved are added to a solution in which the target substance is dissolved to precipitate crystals of the target substance. However, in this method, since a solvent capable of dissolving the target substance remains, it is difficult to obtain crystals of the target substance in a high yield.

An object of the present invention is to provide a method for obtaining thermodynamically stable, high-density substantially ε-HNIW in a short time and with high yield under such circumstances.
The term “substantial ε-HNIW” as used herein refers to a crystal containing 90% or more of ε-HNIW. Also, ε-HNI
Even with W, an acute angle shape such as a rhombus has high sensitivity and cannot be used as an explosive composition. Since the shape of the crystal greatly affects the sensitivity, it is necessary to manufacture ε-HNIW having a shape with low sensitivity.

[0010]

Means for Solving the Problems The present inventors dissolved HNIW using a mixed solvent of a good solvent and a poor solvent as a solvent,
Then, ε-HNIW was added as a seed crystal, a poor solvent was added dropwise to precipitate crystals, and a good solvent was further evaporated, thereby succeeding in efficiently obtaining low-sensitivity substantial ε-HNIW efficiently. completed. The good solvent referred to here is a solvent having a boiling point of 150 ° C. or less under normal pressure and capable of dissolving 20 g or more of HNIW in 100 g of the solvent at normal temperature and normal pressure. The term "poor solvent having a higher boiling point than that of a good solvent" as used herein refers to a solvent that cannot dissolve 1 g or more of HNIW per 100 g of a solvent at normal temperature and normal pressure.

Hereinafter, a method for obtaining substantial ε-HNIW of the present invention will be described. HNIW as starting material of the present invention
May be manufactured by any method. For example, HNIW obtained by the method described in WO98-05666 has high purity of HNIW and is preferable as a starting material of the present invention. HNIW has ε-HNI
There are a plurality of crystal forms other than W, but any crystal may be used as a raw material. The general result is α
-HNIW, β-HNIW, or HNIW containing γ-HNIW as a main component, and these are used as raw materials. Here, the main component refers to a case where 60% or more of the main component is contained.

The method for obtaining substantial ε-HNIW of the present invention has the constitution described in the following section. That is, (1) HNIW is dissolved in a mixed solvent of a good solvent and a poor solvent to obtain an HNIW solution. (2) ε-HNI as a seed crystal in the solution of (1) above
Add W. (3) The poor solvent is dropped into the solution of (2). (4) The solvent is evaporated from the solution of the above (3). The mixed solvent used in the above (1) is used to completely dissolve HNIW. Therefore, it is preferable to first dissolve HNIW in a good solvent and then use a poor solvent.

As the good solvent used in the above (1), it is preferable to use a good solvent having a boiling point of 100 ° C. or less in order to facilitate the evaporation of the solvent in the above (4). As the good solvent, ketones such as acetone and methyl ethyl ketone, ethers of tetrahydrofuran and tetrahydropyran, and esters such as ethyl acetate are used.
Two or more of these good solvents may be used as a mixture.

The poor solvent used in the above (1) and (3) is more difficult to evaporate than the good solvent in the above (3).
A poor solvent having a higher boiling point than a good solvent is used. Usually, it is preferable to use a poor solvent whose boiling point is higher than that of a good solvent by 20 ° C. or more under normal pressure. For example, toluene, xylene, ethylbenzene, butylbenzene, cumene, mesitylene and the like are used. When a mixed solvent is used, the amount of the solvent is usually in the range of 5 to 100 ml, preferably 10 to 50 ml per 1 g of HNIW. 5 solvent
When the amount is less than ml, the solution becomes non-uniform at the time of the addition of the poor solvent in the above (3), and α-HNIW may be obtained as a by-product. On the other hand, when the amount of the solvent exceeds 50 ml, a long time is required until the precipitation, and the required amount of the poor solvent dropped in the above (3) increases. The mixing ratio of the good solvent and the poor solvent is usually 1: 1 to 1: 100, preferably 1: 2 to 1:50, by volume.

Ε used as a seed crystal in the above (2)
-The HNIW may be manufactured by any method. The particle size of ε-HNIW used as seed crystals is usually in the range of 1 to 100 microns, preferably 2 to 50 microns, more preferably 5 to 20 microns. The amount of ε-HNIW used as a seed crystal is usually 0.1% to 10% when the raw material is 100.
%, Preferably in the range of 0.5% to 5%, but at a minimum, an amount that does not dissolve and precipitate the seed crystals must be added.

In the above (3), the dropping rate when the poor solvent is dropped is usually 0.1 ml / mi with respect to 1 g of HNIW.
n to 200 ml / min, preferably 5 ml / min
Used in the range of 100 ml / min to 100 ml / min. When the dropping speed is lower than 0.1 ml / min, it takes time to drop. When the dropping speed is higher than 200 ml / min, α-HNIW or β-HNIW may be obtained as a by-product. The amount of the poor solvent to be dropped is usually HNIW
Usually 1 to 500 ml, preferably 5 to 10 per gram.
Used in the range of 0 ml. When the amount of the solvent to be dropped is less than 1 ml, α-HNI is used as a by-product in the above (4).
W or β-HNIW may be obtained. On the other hand, if the amount of the solvent exceeds 500 ml, a large amount of poor solvent is required, which is not preferable.

In the above (4), by evaporating the good solvent in the mixed solvent, the desired substantial ε-HNIW can be obtained in high yield. Although any method may be used for evaporating the good solvent, it is usually carried out by natural evaporation at normal pressure. Evaporation under reduced pressure may be allowed, but rapid pressure reduction such as foaming is not preferred because β-HNIW may be by-produced. When the evaporation amount of the solvent reaches the amount of the added good solvent or more, the crystals are filtered.

In all the above operations (1) to (4), it is preferable to carry out the stirring operation in order to keep the HNIW concentration in the solution uniform or to uniformly disperse the seed crystals. When performed in a stationary state, α-HNIW or β-HNIW may be obtained as a by-product. Further, when substantially ε-HNIW is precipitated in a stirring state, a rounded agglomerated low-sensitivity substantial ε-HNIW can be easily obtained, which is a preferable method. The stirring speed is usually 50 to 1000 rpm, preferably 100 to 500 rpm.
It is performed in the range of rpm. The temperature of all the operations (1) to (4) is usually 0 to 50 ° C, preferably 10 to 10 ° C.
Performed at 40 ° C. Within this range, the temperature may be changed during the operation.

Substantially ε-HNI produced according to the present invention
W is obtained in the form of small crystals round and aggregated,
It is also characterized by low sensitivity. For example, HNIW
Is completely dissolved in a mixed solvent of a good solvent and a poor solvent and crystallized by evaporating the good solvent without stirring.
-HNIW, β-HNIW, or ε-HN with low purity
Although it is IW, even if substantially ε-HNIW is obtained, it is often a highly sensitive crystal having an acute shape such as a rhombus and cannot be used as an explosive composition.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

Example 1 [Example of using α-HNIW → substantially ε-HNIW with a mixed solvent of acetone and toluene]
In a 00 ml beaker, α-HNIW 5 g, acetone 10
Then, 50 ml of toluene was added, and the mixture was stirred at 200 rpm using a three-one motor. Further, 0.05 g of ε-HNIW was added as seed crystals. Cover the top of the beaker with aluminum foil so that acetone does not evaporate, and add 50 ml of toluene at 1 ml / m
The solution was dropped at a drop rate of in. Next, the aluminum foil was removed, and the mixture was stirred at room temperature for 6 hours while evaporating the acetone. The precipitated crystals were filtered and dried, and substantially ε-HNIW4.9.
7 g (994.0%) were obtained. The obtained crystals were round and aggregated. The security of this ε-HNIW
It was confirmed by SK-4810 that it was a drop hammer sensitivity test of 7th grade and a friction sensitivity test of 6th grade, and safety in handling was confirmed.

The structural analysis of the precipitated crystals was performed as follows. As a result of measuring an infrared absorption (hereinafter, referred to as IR) spectrum by a KBr method at a resolution of 2 cm ^-1 , α-
HNIW characteristic absorption, 1166 cm ^-1 absorption, 90
Absorption of 3 cm ^-1 is erased, 1138cm ^-1 which is the characteristic absorption of an ^{ε-HNIW, 1183cm -1, 1193cm} -1 was confirmed. 739 cm ^-1 , 746 cm ^-1 , 75
2cm ^-1, 759cm ^-1, 4 pieces of absorption having a peak top of, 821cm ^-1, 2 pieces of absorption having a peak top of 833cm ^-1 was also confirmed.

These absorption characteristics are described in the literature [Propel
lants, Explosives, Pyrotech
nics 19, 63-69 (1994)]. From the above, it was confirmed that it was substantially converted to ε-HNIW.

[0023]

Example 2 [Example of using β-HNIW → substantially ε-HNIW using a mixed solvent of acetone and toluene]
In a 00 ml beaker, 5 g of β-HNIW, acetone 10
Then, 50 ml of toluene was added, and the mixture was stirred at 200 rpm using a three-one motor. Further, 0.05 g of ε-HNIW was added as seed crystals. Cover the top of the beaker with aluminum foil so that acetone does not evaporate, and add 50 ml of toluene at 1 ml / m
The solution was dropped at a drop rate of in. Next, the aluminum foil was removed, and the mixture was stirred at room temperature for 6 hours while evaporating the acetone. The precipitated crystals were filtered and dried, and substantially ε-HNIW4.9.
7 g (99.4% yield) was obtained. The obtained crystals were round and aggregated. The security of this ε-HNIW
It was confirmed by SK-4810 that it was a drop hammer sensitivity test of 7th grade and a friction sensitivity test of 6th grade, and safety in handling was confirmed. The precipitated crystals were confirmed to be substantially ε-HNIW in the same manner as in Example 1.

[0024]

Example 3 [Example of using α-HNIW → substantially ε-HNIW with a mixed solvent of tetrahydrofuran and toluene] In a 200 ml beaker at room temperature, 5 g of α-HNIW and 10 ml of tetrahydrofuran were added and completely dissolved.
50 ml of toluene was added, and the mixture was stirred at 200 rpm using a three-one motor. Further, ε-HNIW0.0
5 g were added as seed crystals. Cover the top of the beaker with aluminum foil so that acetone does not evaporate.
0 ml was dropped at a dropping rate of 1 ml / min. Next, the aluminum foil was removed, and the mixture was stirred at room temperature for 8 hours while evaporating tetrahydrofuran.
4.95 g (99.0%) of dried, substantially ε-HNIW
I got The obtained crystals were round and aggregated. When the safety of this ε-HNIW was confirmed by JIS-K-4810, it was found that the hammer sensitivity test was 7th grade and the friction sensitivity test was 6th grade, and the handling safety was confirmed. The precipitated crystals were confirmed to be substantially ε-HNIW in the same manner as in Example 1.

[0025]

Comparative Example 1 [Example of α-HNIW → substantially ε-HNIW using a mixed solvent of acetone and toluene and not evaporating the solvent] α-HNIW5 in a 200 ml beaker at room temperature.
g and acetone (10 ml) were added to completely dissolve, then toluene (50 ml) was added, and the mixture was stirred at 200 rpm using a three-one motor. Further, ε-HNIW 0.05
g was added as seed crystals. Cover the top of the beaker with aluminum foil to prevent acetone from evaporating, and add toluene 50
ml was dropped at a dropping rate of 1 ml / min. The precipitated crystals were filtered and dried, but the substantial ε-HNIW was 2.2.
Only 3 g (44.6%) were obtained. The precipitated crystals were round and aggregated. It was confirmed that it was substantially ε-HNIW in the same manner as in Example 1.

[0026]

According to the present invention, high-density and high-energy ε-hexanitrohexaazaisowurtzitanium can be obtained with a purity of 90% or more in a good yield in a short time. Also,
The crystals obtained according to the present invention have low sensitivity.

Claims (12)

[Claims] 1. A method for producing ε-hexanitrohexaazaisowurtzita using seed crystals, comprising dissolving hexanitrohexaazaisowurtzitanium in a mixed solvent of a good solvent and a poor solvent, A method for producing ε-hexanitrohexaazaisowurtzitanium, which comprises preparing a solution, adding ε-hexanitrohexaazaisowurtzitanium as seed crystals, dropping a poor solvent, and further evaporating the solvent. 2. The hexanitrohexaazaisowurtzitane to be dissolved in a solvent is mainly α-hexanitrohexaazaisowurtzitane, β-hexanitrohexaazaisowurtzitane, or γ-hexanitrohexaazaisowurtzitane 2. The process for producing .epsilon.-hexanitrohexaazaisowurtitanium according to claim 1, wherein the component is hexanitrohexaazaisowurtzitanium. 3. The amount of ε-hexanitrohexaazaisowurtzitanium added as seed crystals is 0.1 to 10%.
The ε according to claim 1 or 2, wherein
-Hexanitrohexaazaisosoul titanium manufacturing method. 4. An ε-hexanitrohexaazaisowurtzitanium crystal added as a seed crystal has an average particle size of 1 to 100.
4. The process for producing .epsilon.-hexanitrohexaazaisowurtzitane according to claim 1, wherein the range is in the micron range. 5. A mixed solvent comprising a good solvent and a poor solvent having a higher boiling point than the good solvent.
4. The method for producing ε-hexanitrohexaazaisoulitanium titanium according to any one of 4. 6. The ε-hexanitrohexa according to claim 1, wherein the poor solvent having a boiling point higher than that of the good solvent has a boiling point higher than that of the good solvent by 20 ° C. or more at normal pressure. Azai Soul Titanium manufacturing method. 7. The process for producing ε-hexanitrohexaazaisowurtitanium according to claim 1, wherein the good solvent is at least one of acetone, methyl ethyl ketone, tetrahydrofuran and ethyl acetate. . 8. The method for producing ε-hexanitrohexaazaisowurtzitane according to claim 6, wherein the good solvent is acetone. 9. The method for producing ε-hexanitrohexaazaisowurtzitane according to claim 6, wherein the good solvent is methyl ethyl ketone. 10. The method for producing ε-hexanitrohexaazaisowurtzitane according to claim 6, wherein the good solvent is tetrahydrofuran. 11. The method of claim 5, wherein the poor solvent having a higher boiling point than the good solvent is toluene and / or xylene. 12. The method of claim 11, wherein the poor solvent having a higher boiling point than the good solvent is toluene.