CN105859730A - Method for preparing granular smooth epsilon-HNIW crystal through counter solvent dilution method - Google Patents
Method for preparing granular smooth epsilon-HNIW crystal through counter solvent dilution method Download PDFInfo
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- CN105859730A CN105859730A CN201610293585.XA CN201610293585A CN105859730A CN 105859730 A CN105859730 A CN 105859730A CN 201610293585 A CN201610293585 A CN 201610293585A CN 105859730 A CN105859730 A CN 105859730A
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- hniw
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D487/00—Heterocyclic compounds containing nitrogen atoms as the only ring hetero atoms in the condensed system, not provided for by groups C07D451/00 - C07D477/00
- C07D487/22—Heterocyclic compounds containing nitrogen atoms as the only ring hetero atoms in the condensed system, not provided for by groups C07D451/00 - C07D477/00 in which the condensed system contains four or more hetero rings
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07B—GENERAL METHODS OF ORGANIC CHEMISTRY; APPARATUS THEREFOR
- C07B2200/00—Indexing scheme relating to specific properties of organic compounds
- C07B2200/13—Crystalline forms, e.g. polymorphs
Abstract
The invention relates to a method for preparing a granular smooth epsilon-HNIW crystal through a counter solvent dilution method. The method includes the steps that HNIW is completely dissolved in a crystallization solvent, filtering is conducted, and filtrate is obtained for use; a crystallization kettle is washed with the crystallization solvent firstly, after the crystallization kettle is flushed with a counter solvent, the counter solvent is injected into the crystallization kettle, the water temperature in a jacket of the crystallization kettle is adjusted to range from 25 DEG C to 45 DEG C, heat preservation is conducted for 5-15 min at the stirring speed of 50-100 r/min, the stirring speed is adjusted to range from 450 r/min to 600 r/min, the filtrate is added into the counter solvent dropwise, a crystal starts to be precipitated, and after all the filtrate is added dropwise, stirring continues to be conducted; after the crystal is completely precipitated, filtering is conducted, a crystal and mother liquid are obtained, the crystal is washed and dried, and the HNIW crystal with the epsilon-HNIW content larger than or equal to 95.0% is obtained, the mother liquor is distilled, a distilled crystallization solvent is collected, fractions are filtered, and gamma-HNIW and the counter solvent are obtained. The method has the advantages that operation is easy, the use quantity of the counter solvent is small, the counter solvent can be recycled, reaction conditions are mild, safety and reliability are achieved, environment friendliness and high efficiency are achieved, and industrialization is easily achieved.
Description
Technical field
The present invention relates to a kind of method that anti-solvent dilution method prepares little particle round and smooth ε-HNIW crystal, belong to
In energetic material field.
Background technology
HNIW (Hexanitrohexaazaisowurtzitane, CL-20) is second generation high-explosives, as
The explosive that energy is the highest at present, is expected to, at following alternate application RDX and HMX widely, become high energy
Amount composite explosives or preferably containing of propellant can components.It has been generally acknowledged that HNIW has four kinds at normal temperatures and pressures
Crystal formation, i.e. α, beta, gamma and ε.Contrasting four kinds of crystal formations, ε-HNIW has the highest crystalline density, and
And the most stable, therefore it becomes high explosive and the crystalline substance favored the most applied by propellant
Type.But, presently commercially available common HNIW crystal comes with some shortcomings, and is mainly manifested in crystal morphology
Difference, with sharp corners, the problems such as mechanical sensitivity is high, limiting it should in composite explosives and propellant
With.Therefore HNIW is recrystallized significant, and prepare pattern by recrystallization method
Preferably, the HNIW product of narrower particle size distribution is primary goal, therefore designs correct crystallization processes non-
The most important.
At present, the recrystallization method of explosive mainly has evaporative crystallization method, crystallisation by cooling method, solvent-the most molten
Agent crystallisation, jet crystallization method, crystalization in supercritical fluid.Jet crystallization method and supercritical fluid method are usual
It is used for preparing nano-scale particle, and evaporative crystallization method and crystallisation by cooling method are used for preparing solubility with temperature and become
Change bigger solid.Due to HNIW in various solvents solubility with temperature change be not it is obvious that
Preparing micron order HNIW the most at present it is preferred that both solvent-anti-solvent method, the method technological operation is simple,
Yield is higher, and process is easily controlled, safe and reliable.
M.Ghosh et al. utilizes solvent-anti-solvent method to prepare ε-HNIW.Anti-solvent is normal heptane, institute
Use raw material be α-HNIW, HNIW, ethyl acetate, normal heptane ratio for being 1:2:5, process
Many experiments, recrystallization has reached 500g magnitude, but obtained ε-HNIW pattern be pair centrum or
Person's rhombus, size distribution is in 150-300 μm.
United States Patent (USP) (U.S.5874574) describes the method for a kind of solvent-anti-solvent recrystallization, the most molten
What agent was selected is the alkane of aromatic hydrocarbon and short chain, it is thus achieved that ε-HNIW crystal, but the sample shape obtained
Looks are poor, have sharp corners, broad particle distribution.
Summary of the invention
The technical problem to be solved is to provide a kind of anti-solvent dilution method, and to prepare little particle round and smooth
The method of ε-HNIW crystal, it is contemplated that provide raw material to support for composite explosives grain composition, for
The application study of ε-HNIW provides raw material support, and this method is in crystallization process, it is not necessary to add crystal seed
And additive.
The technical scheme is that a kind of anti-solvent dilution method prepares little
The method of the round and smooth ε-HNIW crystal of grain, including:
1) being dissolved completely in recrystallisation solvent by HNIW, the concentration making HNIW is 0.27-0.40g/mL,
Filtering, filtrate is stand-by；
2) crystallization kettle first washs with recrystallisation solvent, then with after anti-solvent flushing, anti-solvent is injected crystallization kettle
In, in regulation crystallization kettle chuck, water temperature is 25-45 DEG C, is incubated under stir speed (S.S.) 50-100 rev/min
5-15min, then stir speed (S.S.) is adjusted to 450-600 rev/min, drips 1 in anti-solvent) filter that obtains
Liquid, crystal starts to separate out, and after treating all to drip, continues stirring 2-4h,
Above-mentioned two anti-solvent is industry normal octane, industry normal heptane, industry dichloromethane, industry three
The mixture of one or more in chloromethanes, industry carbon tetrachloride, toluene, benzene and industry petroleum ether；
Wherein, the anti-solvent volume injected in crystallization kettle is 1) used by 1-3 times of recrystallisation solvent volume；
3) after crystal separates out completely, filtering, obtain crystal and mother liquor, crystal washs, is dried, and obtains ε-HNIW
The HNIW crystal of content >=95.0%, mother liquor distills, and collects the recrystallisation solvent steamed, and filters cut,
γ-HNIW and anti-solvent, anti-solvent reclaims and is continuing with, and γ-HNIW feeds intake use as raw material.
On the basis of technique scheme, the present invention can also do following improvement.
Further, 1) and 2) in, described recrystallisation solvent is respectively industrial ethyl acetate, industry third
The mixture of one or more in ketone, industrial acetic propyl ester, industrial acetic methyl esters, is preferably industry second
Acetoacetic ester, 1) recrystallisation solvent and 2 used by) used by recrystallisation solvent identical or different.
Further, 1) in, the concentration of described HNIW is 0.30-0.35g/mL.
Further, 2) in, two anti-solvent are industry normal octane.
Further, 2) in, in described crystallization kettle chuck, water temperature is 20-40 DEG C.
Further, 2) in, in anti-solvent, dripping 1) drop rate of filtrate that obtains is 30-50
Ml/min (mL/min).
Further, 3) in, described distillation is that mother liquor distills at 80 DEG C.
Further, 3) in, described be dried in 50 DEG C of baking ovens be dried 8-15h.
Further, 3) in, HNIW content >=99.9% in described HNIW crystal, HNIW crystal
Density >=2.033g/cm3, the observation of HNIW crystal outward appearance is without sharp corners, crystal face flawless, and intergranular is without bag
Folder thing, crystal axial ratio≤1.5.
The invention has the beneficial effects as follows:
1) present invention uses anti-solvent dilution method to prepare little particle ε-HNIW crystal, by regulation technique,
Can obtain the particle that size distribution is 50-180 μm, median is more than 120 μm.This technique has:
Simple to operate, anti-solvent consumption is few, can reclaim, and reaction condition is gentle, safe and reliable, green high-efficient,
And easily realize the advantages such as industrialization.
2) the inventive method is first incubated 10min under low stir speed (S.S.), then heightens stir speed (S.S.), to instead
Solvent drips filtrate, uses two kinds of stir speed (S.S.)s to be because in HNIW solution injects anti-solvent, stir
Mixing speed the highest, HNIW solution mixes evenly with anti-solvent, the crystal grain particle size range separated out
The narrowest, plane of crystal is the most smooth.
3) recrystallisation solvent that mother liquor distills is not entered in air by the present invention, free from environmental pollution.
Accompanying drawing explanation
Fig. 1 is the method stream that the present invention a kind of anti-solvent dilution method prepares little particle round and smooth ε-HNIW crystal
Cheng Tu；
Fig. 2 is raw material ε-HNIW crystal stereoscan photograph；
Fig. 3 is the little particle ε-HNIW crystal stereoscan photograph of embodiment 4 preparation；
Fig. 4 is the little particle ε-HNIW Lens capsule figure of embodiment 4 preparation.
Detailed description of the invention
Principle and feature to the present invention are described below, and example is served only for explaining the present invention, and
Non-for limiting the scope of the present invention.
Embodiment 1
20gHNIW is dissolved in 50mL industrial ethyl acetate, solution is filled in 250mL beaker,
There-necked flask first uses industrial ethyl acetate washes clean, then rinses well with industry normal octane, then to
500mL there-necked flask adds 125ml industry normal octane, there-necked flask is in 40 DEG C of waters bath with thermostatic control；
Turn on agitator, preheats 10min under the 100rpm slow-speed of revolution, before dropping HNIW solution, and agitator
Speed of agitator is transferred to 550rpm, opens constant flow pump and drips the HNIW solution of filtration in there-necked flask,
Drop rate is 35mL/min；After treating all to drip, continue stirring 3h, by crystal and mother liquor mistake
Filter separates, and uses the abundant washing crystal of industrial alcohol 2 times, again filters, and is dried in 50 DEG C of baking ovens
10h, weighs.Crystal weight is 19.1g, and yield is 95.5%.Through measuring, HNIW content >=99.9%；
ε-HNIW content >=95.0%；Density >=2.033g/cm3；Outward appearance is without sharp corners, crystal face flawless, crystalline substance
Between without sandwich thing；Crystal axial ratio≤1.5, projected area girth ratio >=0.80；The granularity separating out crystal is divided
Cloth content between 50-180 μm, accounts for precipitation crystal total amount more than 70%.
Mother liquor distills at 80 DEG C, steams industrial ethyl acetate, collects pending, filters cut,
γ-HNIW and industry normal octane, γ-HNIW and industry normal octane reclaim and are continuing with.
Embodiment 2
40gHNIW is dissolved in 120mL industrial acetic methyl esters, solution is filled into 250mL beaker
In, there-necked flask first uses industrial ethyl acetate washes clean, then rinses well, then with industry normal octane
In 500mL there-necked flask add 200mL reclaim normal octane (for after embodiment 1 many experiments by mother
Liquid unified distillation gained), there-necked flask is in 35 DEG C of waters bath with thermostatic control；Turn on agitator, 100rpm is low
Preheating 10min under rotating speed, before dropping HNIW solution, agitator speed of agitator is transferred to 500rpm,
Opening constant flow pump and drip the HNIW solution of filtration in there-necked flask, drop rate is 40mL/min；
After treating all to drip, continue stirring 3h, crystal is filtered with mother liquor and separates, use industrial alcohol to fill
Divide washing crystal 2 times, again filter, 50 DEG C of baking ovens are dried 10h, weigh.Crystal weight is
37.3g, yield is 93.25%.Through measuring, HNIW content >=99.9%；ε-HNIW content >=95.0%；
Density >=2.033g/cm3；Outward appearance is without sharp corners, crystal face flawless, and intergranular is without sandwiching thing；Crystal length
Axle ratio≤1.5, projected area girth ratio >=0.80；Separate out the size distribution of crystal between 50-180 μm
Content, accounts for precipitation crystal total amount more than 50%.
Mother liquor distills at 80 DEG C, steams industrial acetic methyl esters, collects pending, filters cut,
γ-HNIW and normal octane, γ-HNIW and normal octane reclaim and are continuing with.
Embodiment 3
1kg HNIW is dissolved in 3L industrial ethyl acetate, after being filtered by solution, pours 10L stainless steel into
In Tong, 20L crystallization kettle first uses industrial ethyl acetate washes clean, then rinses well with industry normal octane,
Then in crystallization kettle, add 3L reclaim normal octane (for steaming unified for mother liquor after embodiment 1 many experiments
Evaporate gained), water temperature 35 DEG C in regulation chuck；Turn on agitator, preheats 10min under the 50rpm slow-speed of revolution,
Before dropping HNIW solution, agitator speed of agitator is transferred to 450rpm, opens constant flow pump to crystallization kettle
The HNIW solution that middle dropping is filtered, drop rate is 35mL/min；After treating all to drip, continue
Continuous stirring 3h, filters crystal with mother liquor and separates, use the abundant washing crystal of industrial alcohol 2 times, again
Filter, 50 DEG C of baking ovens are dried 10h, weigh.Crystal weight is 920g, and yield is 92%.Warp
Measuring, HNIW content >=99.9%；ε-HNIW content >=95.0%；Density >=2.033g/cm3；Outward
Seeing without sharp corners, crystal face flawless, intergranular is without sandwiching thing；Crystal axial ratio≤1.5, projected area
Girth ratio >=0.80；The size distribution of precipitation crystal content between 50-180 μm, accounts for precipitation crystal total
Amount more than 60%.
Mother liquor distills at 80 DEG C, steams industrial ethyl acetate, collects pending, filters cut,
γ-HNIW and normal octane, γ-HNIW and normal octane reclaim and are continuing with.
Embodiment 4
4kgHNIW is dissolved in 10.0L industrial ethyl acetate, pours 10L into after being filtered by solution stainless
In steel drum, 50L crystallization kettle first uses industrial ethyl acetate washes clean, then rinses well with industry normal octane,
Then in crystallization kettle, add 20.0L industry normal octane, water temperature 37 DEG C in regulation chuck；Turn on agitator,
Preheating 10min under the 50rpm slow-speed of revolution, before dropping HNIW solution, agitator speed of agitator is transferred to
450rpm, opens constant flow pump and drips the HNIW solution of filtration in crystallization kettle, and drop rate is
40mL/min；After treating all to drip, continue stirring 3h, crystal is filtered with mother liquor and separates, make
With the abundant washing crystal of industrial alcohol 2 times, again filter, 50 DEG C of baking ovens are dried 10h, weigh.
Crystal weight is 3805g, and yield is 95.12%.Through measuring, HNIW content >=99.9%；ε-HNIW
Content >=95.0%；Density >=2.033g/cm3；As it is shown on figure 3, ε-HNIW outward appearance prepared by the present embodiment
Without sharp corners, crystal face flawless, intergranular is without sandwiching thing, and existing raw material ε-HNIW crystal morphology is poor,
With sharp corners, mechanical sensitivity is high, and crystal face has crackle, intergranular to have double team thing, sees Fig. 2；Crystal is long
Short axle ratio≤1.5, projected area girth ratio >=0.80；As shown in Figure 4, the size distribution separating out crystal exists
Content between 50-180 μm, accounts for precipitation crystal total amount more than 65%.
Mother liquor distills at 80 DEG C, steams industrial ethyl acetate, collects pending, filters cut,
γ-HNIW and industry normal octane, γ-HNIW and industry normal octane reclaim and are continuing with.
In above-described embodiment 1 and 2, flask used is crystallization kettle, because dosage is different, and crystallization kettle title
Difference, when dosage is few, is flask；When dosage is big, being crystallization kettle, simply volume is had any different, because of
This, used by embodiment 1 and 2, flask is without departing from the scope of claim.
The foregoing is only presently preferred embodiments of the present invention, not in order to limit the present invention, all in the present invention
Spirit and principle within, any modification, equivalent substitution and improvement etc. made, should be included in this
Within bright protection domain.
Claims (9)
1. the method that anti-solvent dilution method prepares little particle round and smooth ε-HNIW crystal, its feature exists
In, including:
1) being dissolved completely in recrystallisation solvent by HNIW, the concentration making HNIW is 0.27-0.40g/mL,
Filtering, filtrate is stand-by；
2) crystallization kettle first washs with recrystallisation solvent, then with after anti-solvent flushing, anti-solvent is injected crystallization kettle
In, in regulation crystallization kettle chuck, water temperature is 25-45 DEG C, is incubated under stir speed (S.S.) 50-100 rev/min
5-15min, then stir speed (S.S.) is adjusted to 450-600 rev/min, drips 1 in anti-solvent) filter that obtains
Liquid, crystal starts to separate out, and after treating all to drip, continues stirring 2-4h,
Above-mentioned two anti-solvent is industry normal octane, industry normal heptane, industry dichloromethane, industry three
The mixture of one or more in chloromethanes, industry carbon tetrachloride, toluene, benzene and industry petroleum ether；
Wherein, the anti-solvent volume injected in crystallization kettle is 1) used by 1-3 times of recrystallisation solvent volume；
3) after crystal separates out completely, filtering, obtain crystal and mother liquor, crystal washs, is dried, and obtains ε-HNIW
The HNIW crystal of content >=95.0%, mother liquor distills, and collects the recrystallisation solvent steamed, and filters cut,
γ-HNIW and anti-solvent, anti-solvent reclaims and is continuing with, and γ-HNIW feeds intake use as raw material.
Method the most according to claim 1, it is characterised in that 1) and 2) in, described knot
Brilliant solvent is respectively in industrial ethyl acetate, industrial acetone, industrial acetic propyl ester, industrial acetic methyl esters
The mixture of one or more, 1) recrystallisation solvent and 2 used by) used by recrystallisation solvent identical or different.
Method the most according to claim 2, it is characterised in that described recrystallisation solvent is industry second
Acetoacetic ester.
Method the most according to claim 1, it is characterised in that 1) in, described HNIW
Concentration be 0.30-0.35g/mL.
Method the most according to claim 1, it is characterised in that 2) in, two anti-solvent are equal
For industry normal octane.
Method the most according to claim 1, it is characterised in that 2) in, described crystallization kettle presss from both sides
In set, water temperature is 20-40 DEG C.
Method the most according to claim 1, it is characterised in that 2) in, drip in anti-solvent
Adding 1) drop rate of filtrate that obtains is 30-50 ml/min.
Method the most according to claim 1, it is characterised in that 3) in, described distillation is female
Liquid distills at 80 DEG C, described be dried in 50 DEG C of baking ovens be dried 8-15h.
Method the most according to claim 1, it is characterised in that 3) in, described HNIW
HNIW content >=99.9% in crystal, HNIW crystalline density >=2.033g/cm3, HNIW crystal outward appearance
Observing without sharp corners, crystal face flawless, intergranular is without sandwiching thing, crystal axial ratio≤1.5.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106117229A (en) * | 2016-08-31 | 2016-11-16 | 山西北化关铝化工有限公司 | A kind of preparation method of speciality Hexanitrohexaazaisowurtzitane |
| CN106317061A (en) * | 2016-08-22 | 2017-01-11 | 北京理工大学 | Method for preparing large-grain smooth epsilon-HNIW crystals by different-concentration process |
| KR20210088879A (en) * | 2020-01-07 | 2021-07-15 | 국방과학연구소 | Hniw recrystallization method |
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| US5973149A (en) * | 1997-10-29 | 1999-10-26 | Snpe | Process for producing the epsilon polymorphic form of hexanitrohexaazaisowurtzitane |
| US20030130503A1 (en) * | 2002-01-09 | 2003-07-10 | Hamilton R. Scott | Crystallization of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazatetracyclo[5.5.0.05,903,11]-dodecane |
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| US5973149A (en) * | 1997-10-29 | 1999-10-26 | Snpe | Process for producing the epsilon polymorphic form of hexanitrohexaazaisowurtzitane |
| US20030130503A1 (en) * | 2002-01-09 | 2003-07-10 | Hamilton R. Scott | Crystallization of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazatetracyclo[5.5.0.05,903,11]-dodecane |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106317061A (en) * | 2016-08-22 | 2017-01-11 | 北京理工大学 | Method for preparing large-grain smooth epsilon-HNIW crystals by different-concentration process |
| CN106317061B (en) * | 2016-08-22 | 2019-02-12 | 北京理工大学 | A kind of method that various concentration method prepares the round and smooth ε-HNIW crystal of bulky grain |
| CN106117229A (en) * | 2016-08-31 | 2016-11-16 | 山西北化关铝化工有限公司 | A kind of preparation method of speciality Hexanitrohexaazaisowurtzitane |
| KR20210088879A (en) * | 2020-01-07 | 2021-07-15 | 국방과학연구소 | Hniw recrystallization method |
| KR102336825B1 (en) | 2020-01-07 | 2021-12-09 | 국방과학연구소 | Hniw recrystallization method |
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