CN115724705B - Preparation method of transition metal particle coated pentaaminotetrazole - Google Patents
Preparation method of transition metal particle coated pentaaminotetrazole Download PDFInfo
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- CN115724705B CN115724705B CN202111015184.5A CN202111015184A CN115724705B CN 115724705 B CN115724705 B CN 115724705B CN 202111015184 A CN202111015184 A CN 202111015184A CN 115724705 B CN115724705 B CN 115724705B
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- pentaaminotetrazole
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- WURGAKORBPRKIL-UHFFFAOYSA-N tetrazolidine-1,2,3,4,5-pentamine Chemical compound NC1N(N)N(N)N(N)N1N WURGAKORBPRKIL-UHFFFAOYSA-N 0.000 title claims abstract description 51
- 229910052723 transition metal Inorganic materials 0.000 title claims abstract description 27
- 150000003624 transition metals Chemical class 0.000 title claims abstract description 27
- 239000002923 metal particle Substances 0.000 title claims abstract description 25
- 238000002360 preparation method Methods 0.000 title claims abstract description 9
- 238000000034 method Methods 0.000 claims abstract description 37
- 238000001953 recrystallisation Methods 0.000 claims abstract description 9
- 239000000243 solution Substances 0.000 claims description 19
- 238000003756 stirring Methods 0.000 claims description 16
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 12
- HHVIBTZHLRERCL-UHFFFAOYSA-N sulfonyldimethane Chemical compound CS(C)(=O)=O HHVIBTZHLRERCL-UHFFFAOYSA-N 0.000 claims description 12
- 238000010438 heat treatment Methods 0.000 claims description 9
- 239000011259 mixed solution Substances 0.000 claims description 8
- 239000000725 suspension Substances 0.000 claims description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 6
- 238000001816 cooling Methods 0.000 claims description 5
- 238000001035 drying Methods 0.000 claims description 4
- 238000001914 filtration Methods 0.000 claims description 3
- 239000002245 particle Substances 0.000 claims description 3
- 238000004321 preservation Methods 0.000 claims description 3
- 238000005406 washing Methods 0.000 claims description 3
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims description 2
- 229910052802 copper Inorganic materials 0.000 claims description 2
- 239000010949 copper Substances 0.000 claims description 2
- 238000003760 magnetic stirring Methods 0.000 claims description 2
- 238000001556 precipitation Methods 0.000 claims description 2
- 229910052725 zinc Inorganic materials 0.000 claims description 2
- 239000011701 zinc Substances 0.000 claims description 2
- 238000005979 thermal decomposition reaction Methods 0.000 abstract description 15
- 230000004913 activation Effects 0.000 abstract description 7
- 238000000576 coating method Methods 0.000 abstract description 5
- 239000011248 coating agent Substances 0.000 abstract description 4
- 230000007246 mechanism Effects 0.000 abstract description 3
- 230000001105 regulatory effect Effects 0.000 abstract description 2
- 239000003054 catalyst Substances 0.000 description 15
- 239000000463 material Substances 0.000 description 13
- 230000003197 catalytic effect Effects 0.000 description 6
- 238000000197 pyrolysis Methods 0.000 description 6
- 238000005054 agglomeration Methods 0.000 description 4
- 230000002776 aggregation Effects 0.000 description 4
- XEKOWRVHYACXOJ-UHFFFAOYSA-N Ethyl acetate Chemical compound CCOC(C)=O XEKOWRVHYACXOJ-UHFFFAOYSA-N 0.000 description 3
- 229910052782 aluminium Inorganic materials 0.000 description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 3
- 230000006399 behavior Effects 0.000 description 3
- 239000012153 distilled water Substances 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- IAZDPXIOMUYVGZ-UHFFFAOYSA-N Dimethylsulphoxide Chemical compound CS(C)=O IAZDPXIOMUYVGZ-UHFFFAOYSA-N 0.000 description 2
- 239000000654 additive Substances 0.000 description 2
- 238000006555 catalytic reaction Methods 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000002485 combustion reaction Methods 0.000 description 2
- 239000002105 nanoparticle Substances 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 238000000498 ball milling Methods 0.000 description 1
- 238000005229 chemical vapour deposition Methods 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000002591 computed tomography Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000001755 magnetron sputter deposition Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000002715 modification method Methods 0.000 description 1
- IJGRMHOSHXDMSA-UHFFFAOYSA-N nitrogen Substances N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen group Chemical group [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 238000001878 scanning electron micrograph Methods 0.000 description 1
- 239000007790 solid phase Substances 0.000 description 1
- 229910000314 transition metal oxide Inorganic materials 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
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Abstract
The invention discloses a preparation method of transition metal particle coated pentaamino tetrazole. The method comprises the following steps: and coating transition metal particles on the surface of pentaaminotetrazole by adopting a solution recrystallization method, so as to prepare a modified sample. The transition metal particles are coated on the surface of the pentaaminotetrazole, so that the contact mode of the transition metal particles and the pentaaminotetrazole can be changed, the thermal decomposition of the pentaaminotetrazole can be obviously promoted, the activation energy of the pentaaminotetrazole is reduced, and the thermal decomposition mechanism of the pentaaminotetrazole is regulated.
Description
Technical Field
The invention relates to a preparation method for coating transition metal particles on pentaaminotetrazole, belonging to the technical field of modification of energetic materials.
Background
The transition metal is used as a catalyst, has the advantages of good heat conduction performance, higher heat energy value, easily available raw materials and the like, is commonly used in the field of energetic materials, and can catalyze the thermal decomposition of the energetic materials by mixing the transition metal with the energetic materials, but the nano particles are often agglomerated on the surface of the energetic materials due to the defects of easy agglomeration and the like, so that the catalytic performance of the nano particles is limited.
Changing the contact mode of the catalyst and the energetic material is an effective method for improving the catalytic performance of the catalyst at present. The surface coating is a method commonly used at present, and the catalyst is coated on the surface of the energetic material or the energetic material is coated on the surface of the catalyst by a certain means, so that the contact mode of the catalyst and the energetic material can be effectively changed, the combination of the catalyst and the energetic material is tighter, and the catalytic effect is better.
In the paper of pyrolysis, combustion characteristics and application research of pentaaminotetrazole analogies, cao Chengyang, transition metal oxide and other additives are mixed with pentaaminotetrazole by mechanical ball milling, and the result shows that the contact mode of the additives and the pentaaminotetrazole is not well changed in the mode, and the preparation time of a sample is longer. In the document "preparation of Ditetraethylammonium decahydrodecaborate/nano aluminum composite and its properties", jiang Fan et al dispersed ethyl acetate and dried to prepare a mixture of BHN-10 and nano aluminum, found that a relatively serious agglomeration phenomenon occurred between the surface of BHN-10 and nano aluminum.
In the prior art, other similar coating methods, such as a chemical vapor deposition method, a magnetron sputtering method and the like, however, the prior art method has the characteristics of low efficiency, high cost, complex process and the like, and further application of the prior art method is limited.
Disclosure of Invention
The invention aims to provide a method for preparing transition metal particle coated pentaamino tetrazole by adopting a solution recrystallization method. By the modification method, the contact mode of pentaaminotetrazole and the catalyst can be changed, the catalytic performance of the catalyst can be better improved, the sample preparation time can be shortened, the cost is low, and the process is simple. Under the catalysis of transition metal particles, the thermal decomposition activation energy of pentaaminotetrazole can be effectively reduced, the thermal decomposition mechanism of pentaaminotetrazole is changed, and the pyrolysis performance of pentaaminotetrazole is optimized.
In order to achieve the above object, a method for preparing transition metal particle coated pentaaminotetrazole adopts a solution recrystallization method, mainly comprising the following steps:
(1) Adding penta-aminotetrazole into a mixed solution of dimethyl sulfone (DMSO) and distilled water, heating while stirring, and heating the solution to 45-65 ℃ to completely dissolve penta-aminotetrazole in the mixed solution;
(2) Adding transition metal particles into the mixed solution, and stirring for a period of time until the transition metal particles are uniformly dispersed to form a suspension;
(3) Heating the suspension obtained in the step (2) while stirring, heating the solution to 85-100 ℃, and preserving heat for 0.5-2h;
(4) After heat preservation is finished, cooling the solution obtained in the step (3) while stirring, cooling the solution to room temperature, and preserving heat for 2-4 hours until precipitation is completely separated from the solution;
(5) Filtering, washing and drying to obtain the sample.
Further, the mass ratio of pentaaminotetrazole to the transition metal particles is 99-95%:1-5%.
Further, the pentaaminotetrazole and the transition metal particles are both micron-sized particles.
Further, the transition metal particles are any one of copper and zinc.
Further, in the step (1), the volume ratio of the dimethyl sulfone to the distilled water is 1:2-1:5.
Further, in the step (1), stirring is carried out for 10-20min until the materials are uniformly dispersed, so as to form a suspension.
Further, in the steps (1) to (4), the stirring mode is magnetic stirring, and the stirring speed is 1500-2000r/min.
Further, in the step (5), drying is performed at 50-80 ℃ for 3-4 hours.
Compared with the prior art, the invention has the remarkable advantages that:
(1) The transition metal particles are coated on the surface of the pentaaminotetrazole by adopting a solution recrystallization method, so that the contact mode of the catalyst and the pentaaminotetrazole can be changed, the agglomeration phenomenon is avoided, and the catalytic performance of the catalyst is improved.
(2) The solution recrystallization method is adopted, so that the sample preparation process is simpler, economical and efficient.
(3) The addition of the transition metal particles as the catalyst optimizes the pyrolysis behavior of pentaaminotetrazole, provides feasible theoretical support for the later combustion characteristic research of pentaaminotetrazole, and simultaneously provides reliable reference for modification and optimization of other types of energetic materials.
Drawings
FIG. 1 (a) is an SEM of pentaaminotetrazole; fig. 1 (b) is an SEM image of copper powder coated on the surface of pentaaminotetrazole.
FIG. 2 is a graph of TG-DTG of pentaaminotetrazole coated with copper powder and uncoated with copper powder.
FIG. 3 is a graph of the results of fitting the activation energy calculated by KAS method.
Fig. 4 is a graph showing the fitting result of a model for predicting thermal decomposition by CR method.
Detailed Description
The invention is described in further detail below with reference to the drawings and examples.
Examples
In the embodiment, a solution recrystallization method is adopted to coat copper powder serving as a metal catalyst on the surface of pentaaminotetrazole to prepare a modified sample, a scanning electron microscope is adopted to represent the coating effect, and a TG-DSC technology is adopted to represent the thermal decomposition behavior, and the specific steps are as follows:
(1) Firstly, the mass ratio of pentaaminotetrazole to copper powder is 97 percent: weighing the medicines for standby according to the proportion of 3%;
(2) Then pentaaminotetrazole is added into a mixed solution of dimethyl sulfoxide (DMSO) and distilled water in a volume ratio of 1:2, and the whole system is heated to 45 ℃;
(3) Starting a magnetic stirrer, and regulating the rotating speed to 1500r/min to completely dissolve the pentaaminotetrazole;
(4) Adding the weighed copper powder into the mixed solution obtained in the step (3), stirring for 15min until the copper powder is uniformly dispersed to form suspension, heating to 85 ℃ while stirring, and preserving heat for 0.5h;
(5) After the heat preservation is finished, cooling the solution in the step (4) to room temperature while stirring, and preserving the heat for 2 hours at the room temperature until all the precipitate is separated out;
(6) Filtering by a suction filter, washing with water for three times, and baking the obtained sample for 4 hours at 50 ℃ to obtain the copper powder coated pentaaminotetrazole (modified sample).
(7) The TG-DSC test was performed on unmodified pentaaminotetrazole (unmodified sample) and modified sample. 1-4mg of sample was taken per test and placed on an open alumina crucible using (. Beta. =5, 10, 15, 20℃min -1 ) The temperature rising rates are four, the test temperature ranges from 100 ℃ to 750 ℃, and the test gas atmosphere is nitrogen. Meanwhile, the activation energy is calculated by adopting a KAS (KAS) conversion rate method, and a thermal decomposition model is predicted by a CR (computed tomography) method so as to compare and analyze the thermal decomposition behaviors of an unmodified sample and a modified sample.
The formulas needed to be used are as follows:
KAS method:
CR method:
the thermal decomposition model for solid phase materials is shown below.
As can be seen from fig. 1, after the modification by the solution recrystallization method, the surface of pentaaminotetrazole is tightly covered by copper powder, and the pentaaminotetrazole is tightly distributed without agglomeration phenomenon. As can be seen from fig. 2, the pyrolysis rate of the modified pentaaminotetrazole is accelerated, the copper powder catalyzes the pyrolysis of the pentaaminotetrazole, and fig. 3 is a graph of a fitting result of calculating activation energy by using a KAS method. According to the calculation result of KAS and other conversion methods, the thermal decomposition activation energy is reduced from 185.5kJ/mol to 138.8kJ/mol. Fig. 4 is a graph showing the fitting result of the prediction of the thermal decomposition model by the CR method and the table equation. According to the prediction result of the CR method, the thermal decomposition model of the modified sample is changed from the F4 model of the unmodified sample to the F3 model.
The above description shows that after the penta-amino tetrazole is modified by the solution recrystallization method, the contact mode of the penta-amino tetrazole and the catalyst is changed, and the catalytic performance of the catalyst is better improved. Under the catalysis of transition metal particles, the thermal decomposition activation energy of pentaaminotetrazole can be effectively reduced, the thermal decomposition mechanism of pentaaminotetrazole is changed, and the pyrolysis performance of pentaaminotetrazole is optimized.
Claims (8)
1. The preparation method of the transition metal particle coated pentaaminotetrazole is characterized by adopting a solution recrystallization method and comprising the following steps of:
(1) Adding penta-amino tetrazole into a mixed solution of dimethyl sulfone and water, heating while stirring, and heating the solution to 45-65 ℃ to enable the penta-amino tetrazole to be completely dissolved in the mixed solution;
(2) Adding transition metal particles into the mixed solution, and stirring for a period of time until the transition metal particles are uniformly dispersed to form a suspension;
(3) Heating the suspension obtained in the step (2) while stirring, heating the solution to 85-100 ℃, and preserving heat for 0.5-2h;
(4) After heat preservation is finished, cooling the solution obtained in the step (3) while stirring, cooling the solution to room temperature, and preserving heat for 2-4 hours until precipitation is completely separated from the solution;
(5) Filtering, washing and drying to obtain the transition metal particles coated with pentaaminotetrazole.
2. The method of claim 1, wherein the mass ratio of pentaaminotetrazole to transition metal particles is 99-95%:1-5%.
3. The method of claim 1, wherein the pentaaminotetrazole and the transition metal particles are micron-sized particles.
4. The method of claim 1, wherein the transition metal particles are any one of copper and zinc.
5. The method of claim 1, wherein in step (1), the volume ratio of the dimethylsulfone to the water is from 1:2 to 1:5.
6. The method of claim 1, wherein in step (1), stirring is performed for 10-20 minutes until the particles are uniformly dispersed to form a suspension.
7. The method of claim 1, wherein in step (1) to step (4), the stirring is magnetic stirring at a speed of 1500-2000r/min.
8. The method according to claim 1, wherein in step (5), drying is performed at 50 to 80 ℃ for 3 to 4 hours.
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| CN102267982A (en) * | 2011-06-07 | 2011-12-07 | 西北大学 | BTATz (3,6-bis(1-H-1,2,3,4-tetrazole-5-amino)-1,2,4,5-tetrazine) metal energetic complex and preparation method thereof |
| CN110452075A (en) * | 2019-07-24 | 2019-11-15 | 西北工业大学 | The preparation method of polymer matrix Composite Energetic Materials coating modification nano-metal particle |
| CN110981659A (en) * | 2019-12-11 | 2020-04-10 | 湖北航天化学技术研究所 | Method for coating metal hydride by solvent-nonsolvent method |
| CN112341633A (en) * | 2020-11-30 | 2021-02-09 | 广东石油化工学院 | MOFs material with high gas adsorbability and preparation method and application thereof |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102267982A (en) * | 2011-06-07 | 2011-12-07 | 西北大学 | BTATz (3,6-bis(1-H-1,2,3,4-tetrazole-5-amino)-1,2,4,5-tetrazine) metal energetic complex and preparation method thereof |
| CN110452075A (en) * | 2019-07-24 | 2019-11-15 | 西北工业大学 | The preparation method of polymer matrix Composite Energetic Materials coating modification nano-metal particle |
| CN110981659A (en) * | 2019-12-11 | 2020-04-10 | 湖北航天化学技术研究所 | Method for coating metal hydride by solvent-nonsolvent method |
| CN112341633A (en) * | 2020-11-30 | 2021-02-09 | 广东石油化工学院 | MOFs material with high gas adsorbability and preparation method and application thereof |
Non-Patent Citations (1)
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