CN1125215A

CN1125215A - Process for making high explosive microgranula by using supercritical fluid devitrification method

Info

Publication number: CN1125215A
Application number: CN95111643A
Authority: CN
Inventors: 周展云; 蔡建国; 杨忠文
Original assignee: East China University of Science and Technology
Current assignee: East China University of Science and Technology
Priority date: 1995-05-30
Filing date: 1995-05-30
Publication date: 1996-06-26
Anticipated expiration: 2015-05-30
Also published as: CN1036194C

Abstract

The prepn. process of high explosive particles by using supercritical fluid devitrification method mainly includes such processes of using acetone-cyclohexanone as solvent, using supercritical CO2 fluid as devitrification agent, making HMX dissolve in solvent to form a transparent solution and place said solution in a high-pressure crystallization still, then introducing the supercritical CO2 fluid into said still to make the HMX separate out in the microcrystalline form so as to obtain the invented product.

Description

The technology of making high explosive microgranula by using supercritical fluid devitrification method

The present invention relates to a kind of preparation method of microparticle, particularly a kind of preparation method of explosive microparticle.

As everyone knows, the explosive of microparticle attitude has the high characteristic of detonating rate, so very pays attention to the research of microparticle explosive on the engineering.The seventies ring tetramethylene four ammonium nitrates (being called for short HMX) that grow up are a kind of high explosives of excellent property, but its production technique only can be prepared the thicker product of granularity, its median size is between 150～350 μ m, and can not be with general machining process refinement, thereby have limited the performance of its performance.So thirsting for relevant scientific worker, branch of industry provides a kind of simple and easy to do safe and reliable fine HMX particulate method of producing, to satisfy on the engineering demand to microparticle.

The objective of the invention is to overcome the above-mentioned shortcoming of prior art, a kind of quick, easy, safe and reliable method of producing the HMX microparticle is provided, can satisfy the needs of branch of industry microparticle attitude explosive.

Design of the present invention is such: the contriver is according to the thin Principle of Process of supercritical fluid devitrification system, characteristic with HMX itself, select a class not only solubilized HMX, but also the solvent that can dissolve each other fully with supercutical fluid (being called for short SCF), HMX is then insoluble or be insoluble among the SCF, by the crystallization operation of supercutical fluid, realize the thin process of system of HMX high explosive then.

The present invention also is achieved in that invention on the basis of lot of experiments, selects acetone or the pimelinketone solvent as HMX, and HMX has good solubility therein; Select a kind of supercutical fluid CO ₂(be called for short to become Ashamed crystallization agent, because Can dissolve each other fully with acetone, pimelinketone, HMX then is insoluble in

In, therefore can carefully operate by the system of the thin principle realization of the system of supercritical fluid devitrification HMX, detailed process is summarized as follows:

At first HMX is dissolved in formation one clear solution in acetone or the pimelinketone, the concentration of its adaptation is 1～5g/100ml, then solution is placed one to have the high pressure crystal still that chuck heats, and temperature in the kettle should be controlled at 35～50 ℃, then opens steel cylinder, CO ₂Gas feeds in the high piezocrystal still after regulating flow by compressor boost and control valve.The big I of compressor delivery pressure is regulated and control by pressure-regulator according to the requirement of crystallization technology, and suitable pressure range is 6～15MPa, enters in the still The big I of flow regulate by control valve, its suitable flow is 3～NL/min.Along with

Feeding, the still internal pressure can increase automatically in 6～15MPa, simultaneously solution begins to become muddy, the small product grain that shows HMX generates, till HMX was fully separated out, whole crystallization process only need 2～5 minutes.Stop then feeding

Closed control valve, discharge valve at the bottom of the unlatching still, solvent (acetone or pimelinketone) is discharged from by strainer immediately, the HMX crystal grain of separating out then is trapped within on the screen plate of strainer, unload strainer, the microparticle of HMX is taken off from screen plate, be product of the present invention, detect with scanning electronic microscope: the median size of HMX is 1.0～10 μ m.

When being solvent with acetone, the concentration of HMX is preferably 1.0～2.0g/100ml; When being solvent with the pimelinketone, the concentration of HMX is preferably 3.0～5.0g/100ml.

HMX concentration is low to be helped making averageparticle and is HMX crystal about 1 μ m, is HMX crystal about 10 μ m otherwise then can make mean particle size.Select the concentration of regulation and control HMX, can obtain to specify yardstick HMX crystal product.

Further illustrate content of the present invention below in conjunction with drawings and Examples, but they do not limit protection scope of the present invention.

Fig. 1 is for getting the process flow diagram of HMX microparticle with the supercritical fluid devitrification legal system:

Wherein:

1---steel cylinder, CO ₂Gas;

2---compressor makes CO ₂Gas boosting;

3---pressure-regulator, regulate the pressure of compressor outlet automatically;

4---control valve, regulation and control fluidic flow;

5---interchanger will enter the CO of high pressure crystal still ₂Be warming up to 30～50 ℃;

6---the high pressure crystal still;

7,9---discharge valve, be loaded on the high pressure crystal still below, lay respectively on the strainer upper/lower terminal;

8---strainer, place the below of high pressure crystal still, can load and unload fast, its top and bottom are connected with discharge valve 7,9 respectively.

The solution that at first will be dissolved with HMK places high pressure crystal still (6), opens successively then steel cylinder (1), and compressor (2), pressure regulator (3), control valve (4) make the CO in the steel cylinder (1)₂Gas Enter in the high pressure crystal still after (2) supercharging of the compressed machine of body and control valve (4) the adjust flux size. Press The size of contracting machine (2) outlet pressure is regulated and control by pressure regulator (3) according to technological requirement; Enter height Flow in the piezocrystallization still is regulated and control by control valve (4). Overcritical through heat exchanger (5) heat temperature raising The CO of attitude₂Fluid is imported in the high crystallization kettle, and it can dissolve each other with solvent fully as the crystallization agent, and solute HMK just separates out, and is suspended in (solvent that contains the supercritical fluid devitrification agent) in the solvent with the crystallite attitude. Temperature in the high pressure crystal still is regulated and control by the hot water jacket of peripheral hardware, and optimum range is 30～50 ℃, high pressure The crystallization kettle internal pressure depends on crystallization technology, can be regulated and control by pressure regulator (3), suitable pressure limit Be 6～15MPa, the operating time of Crystallization Process only needed to finish in 2～5 minutes, then closing control Valve (4) is opened discharge valve 7,9, and solvent is discharged (for prepare HMK next time through filter (8) is rear Solution is used), the HMK microparticle of separating out then is trapped within on the filter of filter (18), unloads Filter (8) takes out solid HMK, is the said product of the present invention. So again and again operation.

Embodiment 1

To be dissolved with the acetone soln of HMK 1.41g/100ml, place a high pressure crystal still that has visor and a chuck heating unit,, open steel cylinder (1) then and emit CO by chuck heat temperature raising to 37～39 ℃ ₂Compressed machine (2) supercharging, by the pressure-regulator pressure regulation to 10MPa, after interchanger (5) is warming up to 37～39 ℃, feed in the high pressure crystal still (6), can see rapidly from visor that solution becomes is mixed, be that fine HMK crystal grain generates, after 4 minutes, closed control valve (4), open discharge valve 7,9, be discharged from (using) behind the solvent process filter (8) for prepare HMK solution next time, the HMK that separates out then is trapped within on the screen plate of strainer (8), unload strainer (8) and take out solid HMK, be the said product of the present invention, detect through scanning electronic microscope, its median size is about 8 μ m.

Embodiment 2

To be dissolved with the pimelinketone solution of HMK 4.431g/100ml, place the high pressure crystal still (6) that has visor and chuck heating unit,, open steel cylinder (1) then and emit CO by chuck heat temperature raising to 34～36 ℃ ₂Compressed machine (2) supercharging, by the pressure-regulator pressure regulation to 12MPa, after interchanger (5) is warming up to 34～36 ℃, feed in the high pressure crystal still (6), from visor, can observe the generation of HMK fine-grain rapidly, after 5 minutes, closed control valve (4) is opened discharge valve 7,9, be discharged from (using) behind the solvent process filter (8) for prepare HMK solution next time, the fine HMK that separates out then is trapped within on the screen plate of strainer (8), unload strainer (8), take out solid HMK, be the said product of the present invention, detect through scanning electronic microscope, its median size is about 10 μ m.

By the foregoing description 1～2 as seen, the thin process of the system of HMK of the present invention has quick, easy, safe and reliable advantage.

Obviously, produce the crystal of finer HMX if desired, then can further reduce the concentration of Solution H MX, but the output of the microparticle of HMX is less relatively at this moment.

Claims

1. the technology of a making high explosive microgranula by using supercritical fluid devitrification method is characterized in that:

(1) be solvent with acetone or pimelinketone, with postcritical CO ₂Fluid is the crystallization agent, HMX is dissolved in forms a clear solution in the solvent, and place the high pressure crystal still, then will

Feed in the still, HMX is separated out from solvent with crystallite attitude form;

(2) operating pressure of high pressure crystal still is 6～15MPa, and working temperature is 35～50 ℃;

(3) concentration of HMX is 1～59/100ml.

2. the method for claim 1, when it is characterized in that making solvent with acetone, the concentration of HMX is 1.0～2.0g/100ml.

3. the method for claim 1, when it is characterized in that making solvent with pimelinketone, the concentration of HMX is 3.2～5.0g/100ml.

4. as the described method of one of claim 1～3, it is characterized in that making mean particle size is 1.0～10 μ m HMX products.