Preparation method of uniform-morphology ammonium perchlorate microrod

Abstract

The invention discloses a preparation method of an ammonium perchlorate microrod with a uniform morphology. The preparation method comprises the following steps: firstly, heating a triethylene glycol saturated solution of ammonium perchlorate under a room temperature condition to a preset high temperature; then adding the high-temperature ammonium perchlorate saturated solution into an acetic acid anti-solvent at a certain temperature at a certain feeding rate for recrystallization; and finally, standing, separating, washing and drying the product to obtain the ammonium perchlorate microrod. The obtained ammonium perchlorate microrod is regular in morphology, good in dispersity and uniform in size, the length is 40-60 microns, and the width is about 10 microns. The method has the advantages of being high in operability, good in repeatability, easy to industrialize and the like.

Description

Technical Field

[0001] The present invention relates to a preparation method, and more particularly to a method for preparing ammonium perchlorate micro-rods with uniform morphology. Background Art

[0002] As an important oxidizer in the field of energetic materials, the morphological characteristics of ammonium perchlorate directly affect key parameters such as combustion performance, thermal decomposition characteristics, and charge density. Therefore, the research on morphology control has always been a hot topic in this field.

[0003] Currently, the preparation of ammonium perchlorate oxidizer faces an important challenge, that is, how to find a simple and feasible synthesis process to achieve the controllable synthesis of high-quality ammonium perchlorate with uniform morphology by reasonably regulating process parameters. In response to this problem, scholars at home and abroad have proposed a series of preparation methods to achieve the uniform morphology of ammonium perchlorate oxidizer. Among them, the antisolvent crystallization method shows certain advantages. CN117285008A adds a high-temperature saturated solution of ammonium perchlorate dissolved in N,N-dimethylformamide to a low-temperature ethyl acetate antisolvent for recrystallization to obtain butterfly-shaped micron ammonium perchlorate with uniform morphology. CN117285010A adds a high-temperature saturated solution of ammonium perchlorate dissolved in N,N-dimethylacetamide to a low-temperature ethyl formate antisolvent for recrystallization to obtain monodisperse and uniform-sized ammonium perchlorate micron cubes.

[0004] Currently, it is possible to prepare ammonium perchlorate with uniform morphology such as butterfly shape and cube by using the existing technology; however, in the existing technology, there is still a lack of reports on the preparation of ammonium perchlorate micro-rods with uniform morphology by the antisolvent crystallization method.

[0005] It should be particularly noted that Zhenye Ma (Journal of Crystal Growth 311 (2009) 4575–4580) used the ceramic membrane antisolvent crystallization method, with acetone as the solvent and ethyl acetate as the antisolvent, to prepare ammonium perchlorate micro-rods. Liu Yang (Research on the Preparation of Ultrafine Ammonium Perchlorate in a Mixed Solvent System, Master's Thesis, 2016) used methanol or ethanol as the solvent and ethyl acetate as the antisolvent to prepare ammonium perchlorate micro-rods. However, the reported ammonium perchlorate micro-rods usually have irregular morphology, poor dispersion, and large size differences. Summary of the Invention

[0006] The object of the present invention is to provide a method for preparing ammonium perchlorate micro-rods with uniform morphology. The obtained ammonium perchlorate micro-rods have regular morphology, good dispersion, uniform size, and advantages such as strong operability, good repeatability, and easy industrialization.

[0007] The technical solution of the present invention is as follows: using triethylene glycol as the solvent and acetic acid as the anti-solvent, adding a high-temperature saturated solution of ammonium perchlorate dissolved in triethylene glycol to the acetic acid anti-solvent, and performing recrystallization to obtain ammonium perchlorate micro-rods with a uniform morphology. The specific steps are as follows: (1) Heating a saturated solution of ammonium perchlorate in triethylene glycol at room temperature to a predetermined high temperature; (2) Adding the above-mentioned high-temperature saturated solution of ammonium perchlorate to the acetic acid anti-solvent for recrystallization; (3) Standing and separating the product, washing, and drying to obtain ammonium perchlorate micro-rods.

[0008] In step (1), the predetermined high temperature is 115 - 130 °C.

[0009] In step (2), the adding rate of the high-temperature saturated solution of ammonium perchlorate is 5 - 15 mL / min.

[0010] In step (2), the temperature of the acetic acid anti-solvent is room temperature.

[0011] In step (2), the volume ratio of the ammonium perchlorate saturated solution to acetic acid is controlled at 0.05 - 0.02, and the recrystallization process is carried out under stirring at 400 - 800 revolutions per minute.

[0012] In step (3), wash with acetic acid multiple times and dry at 100 °C.

[0013] Compared with the prior art, the present invention has the following beneficial effects: 1. The ammonium perchlorate micro-rods prepared by the present invention have a regular morphology, good dispersion, uniform size, a length of 40 - 60 microns, and a width of about 10 microns.

[0014] 2. The high-temperature triethylene glycol solvent increases the supersaturation of ammonium perchlorate crystallization, and triethylene glycol has a high viscosity and is adsorbed on specific crystal planes of ammonium perchlorate, promoting the formation of micro-rods with a uniform morphology.

[0015] 3. The product of the present invention has good stability, good repeatability, and a high yield.

[0016] 4. The raw material ammonium perchlorate of the present invention is industrial ammonium perchlorate, with no restrictions on particle size, morphology, or crystal form. Description of the Drawings

[0017] Figure 1 Scanning electron microscope image of ammonium perchlorate micro-rods with a uniform morphology in Example 1; Figure 2 Scanning electron microscope image of ammonium perchlorate micro-rods with a uniform morphology in Example 2; Figure 3 Scanning electron microscope image of ammonium perchlorate micro-rods with a uniform morphology in Example 3; Figure 4 Scanning electron microscope image of ammonium perchlorate obtained in Comparative Example 1; Figure 5 Scanning electron microscope image of ammonium perchlorate obtained in Comparative Example 2; Figure 6 Scanning electron microscope image of ammonium perchlorate obtained in Comparative Example 3. Specific Embodiments

[0018] The following structural embodiments further illustrate the technical solution of the present invention, but should not be construed as a limitation to the technical solution. Adaptative improvements based thereon fall within the protection scope of the present invention.

[0019] Example 1: Prepare ammonium perchlorate micro-rods with uniform morphology according to the following specific steps (1) Heat the saturated solution of ammonium perchlorate in triethylene glycol at room temperature to a high temperature of 120 °C; (2) Add the above-mentioned high-temperature saturated ammonium perchlorate solution to the acetic acid antisolvent at room temperature at a rate of 10 mL / min for recrystallization; wherein, the volume ratio of the saturated ammonium perchlorate solution to acetic acid is controlled at 0.035, and the recrystallization process is carried out under stirring at 600 revolutions per minute; (3) Let the product stand for separation, wash it with acetic acid multiple times, and dry it at 100 °C to obtain ammonium perchlorate micro-rods.

[0020] Comparative Example 1: The parameters are the same as those in Example 1, wherein the saturated solution of ammonium perchlorate in triethylene glycol is at 25 °C.

[0021] Example 2: Prepare ammonium perchlorate micro-rods with uniform morphology according to the following specific steps (1) Heat the saturated solution of ammonium perchlorate in triethylene glycol at room temperature to a high temperature of 115 °C; (2) Add the above-mentioned high-temperature saturated ammonium perchlorate solution to the acetic acid antisolvent at room temperature at a rate of 5 mL / min for recrystallization; wherein, the volume ratio of the saturated ammonium perchlorate solution to acetic acid is controlled at 0.02, and the recrystallization process is carried out under stirring at 800 revolutions per minute; (3) Let the product stand for separation, wash it with acetic acid multiple times, and dry it at 100 °C to obtain ammonium perchlorate micro-rods.

[0022] Comparative Example 2: The parameters are the same as those in Example 2, wherein the saturated solution of ammonium perchlorate in triethylene glycol is at 60 °C.

[0023] Example 3: Prepare ammonium perchlorate micro-rods with uniform morphology according to the following specific steps (1) Heat the saturated solution of ammonium perchlorate in triethylene glycol at room temperature to a high temperature of 130 °C; (2) Add the above-mentioned saturated ammonium perchlorate solution at a rate of 15 mL / min to the acetic acid antisolvent at room temperature for recrystallization; wherein, the volume ratio of the saturated ammonium perchlorate solution to acetic acid is controlled at 0.05, and the recrystallization process is carried out under stirring at 400 revolutions per minute; (3) Let the product stand for separation, wash it with acetic acid multiple times, and dry it at 100 °C to obtain ammonium perchlorate micro-rods.

[0024] Comparative Example 2: The parameters are the same as in Example 3, wherein the saturated triethylene glycol solution of ammonium perchlorate is at 90 °C.

[0025] Provided by Examples 1-3 Figures 1-3 It can be seen that the ammonium perchlorate micro-rods obtained by the present invention have regular morphology, good dispersibility, uniform size, a length of 40-60 microns, and a width of about 10 microns. Provided by Comparative Examples 1-3 Figures 4-6 It can be seen that when the solvent temperatures in Examples 1-3 of the present invention are changed to room temperature, 60 °C and 90 °C respectively, and other conditions remain unchanged, the morphologies of the obtained products are all mixtures of cubes, cuboids and rod-like bodies, and the particle size differences are large. It can be seen that using triethylene glycol as the solvent and acetic acid as the antisolvent, the temperature of the triethylene glycol solvent needs to be increased to 115-130 °C of the process of the present invention to obtain ammonium perchlorate micro-rods with a uniform morphology.

Claims

1. Preparation method of ammonium perchlorate micro-rods with uniform morphology, characterized in that: Using triethylene glycol as the solvent and acetic acid as the anti-solvent, add the high-temperature solution of ammonium perchlorate dissolved in triethylene glycol to the acetic acid anti-solvent for recrystallization to obtain ammonium perchlorate micro-rods with a uniform morphology. The specific steps are as follows: (1) Heat the saturated solution of ammonium perchlorate in triethylene glycol at room temperature to a predetermined high temperature; (2) Add the above high-temperature saturated solution of ammonium perchlorate to the acetic acid anti-solvent for recrystallization; (3) Let the product stand for separation, wash, and dry to obtain ammonium perchlorate micro-rods.

2. The preparation method of the ammonium perchlorate micro-rods with uniform morphology according to claim 1, characterized in that: In step (1), the predetermined high temperature is 115-130 °C.

3. The preparation method of the ammonium perchlorate micro-rods with uniform morphology according to claim 1, characterized in that: In step (2), the addition rate of the high-temperature saturated solution of ammonium perchlorate is 5-15 mL / min.

4. The preparation method of the ammonium perchlorate micro-rods with uniform morphology according to claim 1, characterized in that: In step (2), the temperature of the acetic acid anti-solvent is room temperature.

5. The preparation method of the ammonium perchlorate micro-rods with uniform morphology according to claim 1, characterized in that: In step (2), the volume ratio of the saturated solution of ammonium perchlorate to acetic acid is controlled at 0.05-0.02, and the recrystallization process is carried out under stirring at 400-800 revolutions per minute.

6. The preparation method of the ammonium perchlorate micro-rods with uniform morphology according to claim 1, characterized in that: In step (3), wash with acetic acid multiple times and dry at 100 °C.

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