A method for detecting components in CG-K(2) explosive

Abstract

The present invention belongs to the technical field of explosive component analysis, and in particular to a method for detecting components in CG-K (2) explosives. The present invention dissolves 2,6-dipicrylamino-3,5-dinitropyridine and a binder in a sample to be tested by dimethylformamide, separates graphite, and obtains the mass of graphite. Acetonitrile is used to extract 2,6-dipicrylamino-3,5-dinitropyridine in the sample to be tested, and the obtained extract is detected by liquid chromatography to obtain the content of 2,6-dipicrylamino-3,5-dinitropyridine. At the same time, the content of fluororubber can be obtained by calculation. The detection method provided by the present invention has simple steps and high accuracy.

Description

Technical Field

[0001] The invention belongs to the technical field of explosive component analysis, and in particular relates to a method for detecting components in CG-K(2) explosive. Background Art

[0002] With the development of modern industry, the performance requirements of explosives are getting higher and higher, and the analysis and detection of various components in explosives are also put forward better requirements. CG-K(2) is an explosive developed by Shanxi Beihua Guan Aluminum Chemical Co., Ltd. with 2,6-dipicrylamino-3,5-dinitropyridine (PYX) as the main component. 2,6-dipicrylamino-3,5-dinitropyridine is mixed with a certain proportion of water and stirred evenly, and then fluororubber and solvent ethyl acetate are slowly added. The resulting mixture is stirred, granulated, filtered, washed, screened and dried to obtain a primary explosive. The obtained primary explosive is mixed with graphite and passivated to obtain CG-K(2) explosive.

[0003] When analyzing the graphite content in CG-K(2), acetone is used to dissolve the binder multiple times and separate the graphite. During this process, some undissolved fluororubber and PYX are easily mixed into the graphite, causing the analysis result to be biased and the graphite content cannot be accurately analyzed.

[0004] However, there is no report on the detection of PYX in CG-K(2) in the prior art. Summary of the invention

[0005] In view of this, the object of the present invention is to provide a method for detecting components in CG-K(2) explosive. The present invention provides a method for determining the content of each component in CG-K(2) explosive.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0007] Take two samples of the same mass to be tested;

[0008] Dissolve a portion of the sample to be tested in dimethylformamide and mix to obtain a solid-liquid mixed system;

[0009] The mixed liquid is separated into solid and liquid, and the obtained solid is dried to obtain a graphite component;

[0010] Dissolve another portion of the sample to be tested in acetonitrile to obtain a test solution;

[0011] The liquid to be tested is subjected to liquid chromatography to obtain a chromatogram to be tested, and the mass of 2,6-dipicrylamino-3,5-dinitropyridine in the mixed explosive is calculated according to the peak area of ​​2,6-dipicrylamino-3,5-dinitropyridine in the chromatogram to be tested and a predetermined standard curve; the standard curve is a standard curve between the peak area and mass concentration of 2,6-dipicrylamino-3,5-dinitropyridine;

[0012] The liquid chromatography detection conditions include: the chromatographic column is C 18 Chromatographic column; mobile phase includes acetonitrile and phosphoric acid aqueous solution; the volume ratio of acetonitrile and phosphoric acid aqueous solution is 60:40; elution mode is isocratic elution; detector is ultraviolet detector; detection wavelength is 365nm;

[0013] The components of the sample to be tested are composed of 2,6-dipicrylamino-3,5-dinitropyridine, fluororubber and graphite;

[0014] The content of fluororubber in the CG-K(2) explosive = the mass of the sample to be tested - the mass of the graphite component - 2,6-dipicrylamino-3,5-dinitropyridine.

[0015] Preferably, the mobile phase flow rate of the liquid chromatography detection is 1 mL / min.

[0016] Preferably, the column temperature of the liquid chromatography detection is 30°C.

[0017] Preferably, the pH value of the phosphoric acid aqueous solution is 3-4.

[0018] Preferably, the volume ratio of the mass of the sample to be tested to dimethylformamide in the solid-liquid mixed system is 1 g: 14-16 mL.

[0019] Preferably, the volume ratio of the mass of the sample to be tested and acetonitrile in the test solution is 0.48-0.52 g:100 mL.

[0020] The invention provides a method for detecting components in CG-K(2) explosive, comprising the following steps: taking two samples of the same mass; dissolving one sample in dimethylformamide to obtain a solid-liquid mixed system; separating the mixed liquid from the solid and the liquid, and drying the obtained solid to obtain a graphite component; dissolving the other sample in acetonitrile to obtain a liquid to be tested; performing liquid chromatography detection on the liquid to be tested to obtain a chromatogram to be tested, and calculating the mass of 2,6-dipicrylamino-3,5-dinitropyridine in the mixed explosive according to the peak area of ​​2,6-dipicrylamino-3,5-dinitropyridine in the chromatogram to be tested and a predetermined standard curve; the standard curve is a standard curve between the peak area and mass concentration of 2,6-dipicrylamino-3,5-dinitropyridine; the liquid chromatography detection conditions include: a chromatographic column of C 18Chromatographic column; mobile phase includes acetonitrile and phosphoric acid aqueous solution; the volume ratio of the acetonitrile and phosphoric acid aqueous solution is 60:40; the elution mode is isocratic elution; the detector is an ultraviolet detector; the detection wavelength is 365nm; the components of the sample to be tested are composed of 2,6-dipicrylamino-3,5-dinitropyridine, fluororubber and graphite; the content of fluororubber in the CG-K (2) explosive = the mass of the sample to be tested - the mass of the graphite component - 2,6-dipicrylamino-3,5-dinitropyridine. The present invention dissolves 2,6-dipicrylamino-3,5-dinitropyridine and a binder in the sample to be tested by dimethylformamide, separates graphite, and obtains the mass of graphite. Acetonitrile is used to extract 2,6-dipicrylamino-3,5-dinitropyridine in the sample to be tested, and the obtained extract is detected by liquid chromatography to obtain the content of 2,6-dipicrylamino-3,5-dinitropyridine. At the same time, the content of fluororubber can be obtained by calculation. The detection method provided by the invention has simple steps and high accuracy. DETAILED DESCRIPTION

[0021] The present invention provides a method for detecting components in CG-K(2) explosive, comprising the following steps:

[0022] Take two samples of the same mass to be tested;

[0023] Dissolve a portion of the sample to be tested in dimethylformamide and mix to obtain a solid-liquid mixed system;

[0024] The mixed liquid is separated into solid and liquid, and the obtained solid is dried to obtain a graphite component;

[0025] Dissolve another portion of the sample to be tested in acetonitrile to obtain a test solution;

[0026] The liquid to be tested is subjected to liquid chromatography to obtain a chromatogram to be tested, and the mass of 2,6-dipicrylamino-3,5-dinitropyridine in the mixed explosive is calculated according to the peak area of ​​2,6-dipicrylamino-3,5-dinitropyridine in the chromatogram to be tested and a predetermined standard curve; the standard curve is a standard curve between the peak area and mass concentration of 2,6-dipicrylamino-3,5-dinitropyridine;

[0027] The liquid chromatography detection conditions include: the chromatographic column is C 18 Chromatographic column; mobile phase includes acetonitrile and phosphoric acid aqueous solution; the volume ratio of acetonitrile and phosphoric acid aqueous solution is 60:40; elution mode is isocratic elution; detector is ultraviolet detector; detection wavelength is 365nm;

[0028] The components of the sample to be tested are composed of 2,6-dipicrylamino-3,5-dinitropyridine, fluororubber and graphite;

[0029] The content of fluororubber in the CG-K(2) explosive = the mass of the sample to be tested - the mass of the graphite component - 2,6-dipicrylamino-3,5-dinitropyridine.

[0030] The present invention dissolves a sample to be tested in dimethylformamide and mixes them to obtain a mixed solution.

[0031] In the present invention, the CG-K(2) explosive is preferably provided by Shanxi Beihua Guan Aluminum Chemical Co., Ltd. In the present invention, the components of the CG-K(2) explosive are composed of 2,6-dipicrylamino-3,5-dinitropyridine, fluororubber and graphite.

[0032] In the present invention, the volume ratio of the mass of the sample to be tested to dimethylformamide in the solid-liquid mixed system is preferably 1 g:14-16 mL, more preferably 1 g:15 mL.

[0033] In the present invention, the mixing method is preferably stirring, and the stirring is preferably manual stirring. In the present invention, the stirring time is preferably 4 to 10 minutes, more preferably 5 to 8 minutes. In the present invention, the stirring is preferably stirred using a stirring rod. In the present invention, during the mixing process, PYX and fluororubber in the sample to be tested will dissolve in dimethylformamide, while graphite will not.

[0034] In the present invention, after the mixing, it is preferred to further include washing the stirring rod with dimethylformamide, and the obtained washing liquid is incorporated into the mixed liquid obtained by mixing.

[0035] After obtaining the mixed liquid, the present invention separates the mixed liquid into solid and liquid, and dries the obtained solid to obtain the graphite component.

[0036] In the present invention, the solid-liquid separation method is preferably centrifugation, the centrifugation speed is preferably 2000 rpm, and the time is preferably 8 minutes. In the present invention, the number of solid-liquid separations is preferably ≥6.

[0037] In the present invention, the drying temperature is preferably 98 to 102° C., more preferably 100° C., and the drying time is preferably 30 to 40 min, more preferably 35 min.

[0038] In the present invention, after the drying, the dried solid is preferably cooled. The present invention does not specifically limit the cooling, and cooling to room temperature is sufficient.

[0039] The present invention dissolves another sample to be tested in acetonitrile to obtain a solution to be tested.

[0040] In the present invention, the purity of the acetonitrile is preferably chromatographically pure. In the present invention, the volume ratio of the mass of the sample to be tested to acetonitrile in the test solution is preferably 0.48-0.52 g:100 mL, more preferably 0.5 g:100 mL.

[0041] After obtaining the test liquid, the invention performs liquid chromatography detection on the test liquid to obtain a test chromatogram, and calculates the content of 2,6-dipicrylamino-3,5-dinitropyridine in the mixed explosive according to the peak area of ​​2,6-dipicrylamino-3,5-dinitropyridine in the test chromatogram and a predetermined standard curve.

[0042] In the present invention, the liquid chromatography detection column is C 18 Chromatographic column, preferably Agilent HC C 18 Column. In the present invention, the length of the chromatographic column is preferably 150 mm, the inner diameter is preferably 4.6 mm, and the filler particle size of the chromatographic column is preferably 5 μm. In the present invention, the mobile phase for liquid chromatography detection comprises acetonitrile and phosphoric acid aqueous solution; the pH value of the phosphoric acid aqueous solution is preferably 3 to 4, more preferably 3; the volume ratio of acetonitrile and phosphoric acid aqueous solution is 60:40; the flow rate of the mobile phase is preferably 1 mL / min. In the present invention, the elution mode of the liquid chromatography detection is isocratic elution; in the present invention, the detector for the liquid chromatography detection is an ultraviolet detector; the detection wavelength is 365 nm. In the present invention, the column temperature for liquid chromatography detection is preferably 30°C.

[0043] In the present invention, the acquisition of the predetermined standard curve preferably comprises the following steps:

[0044] The 2,6-dipicrylamino-3,5-dinitropyridine standard was prepared into a series of concentration standard working solutions using chromatographic grade acetonitrile;

[0045] The standard working solution is tested according to the liquid chromatography test strip, with the peak area of ​​the 2,6-dipicrinyl-3,5-dinitropyridine standard as the horizontal coordinate and the mass of the 2,6-dipicrinyl-3,5-dinitropyridine as the vertical coordinate to obtain the predetermined standard curve; the liquid chromatography detection conditions are preferably the conditions for the liquid chromatography detection described above.

[0046] In the present invention, the concentration of the 2,6-diamidino-3,5-dinitropyridine standard in the standard working solution of the series of concentrations is preferably 30 μg / mL, 40 μg / mL, and 50 μg / mL.

[0047] The technical solutions in the present invention will be described clearly and completely below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0048] Example 1

[0049] 1.1. Preparation of standard solution

[0050] The 2,6-dipicrylamino-3,5-dinitropyridine standard was diluted with the mobile phase to a concentration of 30 μg / mL, 40 μg / mL, and 50 μg / mL, respectively, to obtain a series of concentration standard working solutions.

[0051] 1.2 Linear regression equation

[0052] According to the above-mentioned liquid chromatography detection conditions, the above-mentioned series of concentration standard working solutions were tested, and the chromatographic peak area of ​​2,6-dipicrinyl-3,5-dinitropyridine obtained was used as the ordinate, and the mass of the 2,6-dipicrinyl-3,5-dinitropyridine standard was used as the abscissa to draw a standard curve to obtain a standard curve regression equation. The standard curve regression equation is: y=3874.5996x+2090, the linear range of the standard curve is (30-50) μg / mL, and the correlation coefficient is r=0.9987.

[0053] Example 2

[0054] Weigh 0.5 g (accurate to 0.0002 g) of CG-K(2) explosive sample and place it in a test tube (mass is recorded as m1) with constant weight. Use a pipette to transfer about 7 mL of dimethylformamide to mix with the CG-K(2) explosive sample. Stir with a stirring rod for 5 minutes to dissolve the sample in the dimethylformamide. Then, use about 2 mL of dimethylformamide to wash the stirring rod, and add the washing liquid into the centrifuge test tube to obtain a mixed solution.

[0055] The obtained mixed liquid is centrifuged and the supernatant is poured off. The above operation is repeated 6 times. Then the centrifugal test tube is placed in a constant temperature drying oven at 100°C and dried for 30 minutes. Then, it is taken out and placed in a dryer to cool to room temperature and weighed. The mass obtained by weighing is m2.

[0056] Dissolve 0.5 g of the sample to be tested in 100 mL of acetonitrile to obtain a test solution;

[0057] The liquid to be tested is subjected to liquid chromatography to obtain a chromatogram to be tested. The conditions for liquid chromatography testing are: the chromatographic column is Agilent HC C 18A chromatographic column (inner diameter 4.6 mm, length 150 mm, stationary phase particle size 5 μm); the mobile phase is acetonitrile and phosphoric acid aqueous solution; the volume ratio of the acetonitrile and phosphoric acid aqueous solution is 60:40; the pH value of the phosphoric acid aqueous solution is 3, and the elution mode is isocratic elution; the detector is an ultraviolet detector; the detection wavelength is 365 nm; the flow rate of the mobile phase is 1 mL / min, and the column temperature is 30°C.

[0058] The peak area of ​​the 2,6-dipicrylamino-3,5-dinitropyridine is substituted into the standard curve equation of the 2,6-dipicrylamino-3,5-dinitropyridine, and the mass of the 2,6-dipicrylamino-3,5-dinitropyridine is calculated to be m3.

[0059] The mass concentration of graphite in the sample to be tested = (m2-m1) / 0.5*100% = 10.61%;

[0060] The mass concentration of fluororubber in the sample to be tested = [0.5-(m2-m1)-m3] / 0.5*100% = 9.5%;

[0061] The mass concentration of 2,6-dipicrylamino-3,5-dinitropyridine in the sample to be tested = m3 / 0.5*100% = 79.89%.

[0062] Example 3

[0063] In 0.5743 g of a sample with known content (fluororubber content 0.42%, 2,6-dipicrinyl-3,5-dinitropyridine content 97.53%, graphite content 2.05%), a certain amount of fluororubber 0.1 g, 2,6-dipicrinyl-3,5-dinitropyridine 0.3 g, and graphite 0.1 g were added. Then, the test was performed according to the method of Example 2. The measured fluororubber content was 9.50%, the 2,6-dipicrinyl-3,5-dinitropyridine content was 79.89%, and the graphite content was 10.61%. The measured recoveries were 99.6%, 99.4%, and 99.8%, respectively.

[0064] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for detecting components in CG-K(2) explosive, characterized in that: The following steps are involved: Take two samples of the same mass to be tested; Dissolve a portion of the sample to be tested in dimethylformamide and mix to obtain a solid-liquid mixed system; The solid-liquid mixed system is separated into solid and liquid, and the obtained solid is dried to obtain a graphite component; Dissolve another portion of the sample to be tested in acetonitrile to obtain a test solution; The liquid to be tested is subjected to liquid chromatography detection to obtain a chromatogram to be tested, and the mass of 2,6-dipicrylamino-3,5-dinitropyridine in the mixed explosive is calculated based on the peak area of ​​2,6-dipicrylamino-3,5-dinitropyridine in the chromatogram to be tested and a predetermined standard curve; the standard curve is a standard curve between the peak area and mass concentration of 2,6-dipicrylamino-3,5-dinitropyridine; The liquid chromatography detection conditions include: the chromatographic column is a C18 chromatographic column; the mobile phase includes acetonitrile and phosphoric acid aqueous solution; the volume ratio of acetonitrile and phosphoric acid aqueous solution is 60:40; the elution method is isocratic elution; the detector is an ultraviolet detector; the detection wavelength is 365nm; The components of the sample to be tested are composed of 2,6-dipicrylamino-3,5-dinitropyridine, fluororubber and graphite; The content of fluororubber in the CG-K(2) explosive = the mass of the sample to be tested - the mass of the graphite component - 2,6-dipicrylamino-3,5-dinitropyridine.

2. The detection method according to claim 1, characterized in that: The mobile phase flow rate of the liquid chromatography detection is 1 mL / min.

3. The detection method according to claim 1, characterized in that: The column temperature of the liquid chromatography detection is 30°C.

4. The detection method according to claim 1, characterized in that: The pH value of the phosphoric acid aqueous solution is 3-4.

5. The detection method according to claim 1, characterized in that: The mass ratio of the sample to be tested to the volume ratio of dimethylformamide in the solid-liquid mixed system is 1 g:14-16 mL.

6. The detection method according to claim 1, characterized in that: The mass ratio of the sample to be tested in the test solution to the volume ratio of acetonitrile is 0.48-0.52 g:100 mL.