阅读说明：本技术 多孔空心结构铝热剂及其制备方法 (Porous hollow structure thermite and preparation method thereof ) 是由 黎学明 何苗 谢玉婷 杨文静 何银芳 李安琪 曾旭钟 杨磊 于 2021-09-23 设计创作，主要内容包括：多孔空心结构铝热剂及其制备方法,该方法包括：将葡萄糖水溶液的水热反应产物离心分离并干燥后得到碳球颗粒；将所得碳球颗粒、硝酸铜和氨水在水中超声分散后形成第一悬浮液；将所形成的第一悬浮液进行水浴老化反应；将老化反应产物离心分离并干燥后得到C/Cu前驱体；将所得C/Cu前驱体煅烧后得到空心CuO；再将所得空心CuO、纳米铝粉超声分散于异丙醇和聚乙烯亚胺(PEI)–乙醇混合液后形成第二悬浮液；将所形成的第二悬浮液进行电泳以在阴极沉积得到多孔空心结构的Al/CuO铝热剂。(The porous hollow structure thermite and the preparation method thereof, the method comprises the following steps: centrifugally separating and drying a hydrothermal reaction product of the glucose aqueous solution to obtain carbon sphere particles; ultrasonically dispersing the obtained carbon sphere particles, copper nitrate and ammonia water in water to form a first suspension; carrying out water bath aging reaction on the formed first suspension; centrifugally separating and drying the aging reaction product to obtain a C/Cu precursor; calcining the obtained C/Cu precursor to obtain hollow CuO; ultrasonically dispersing the obtained hollow CuO and nano aluminum powder in a mixed solution of isopropanol and Polyethyleneimine (PEI) -ethanol to form a second suspension; and carrying out electrophoresis on the formed second suspension to deposit the Al/CuO thermite with a porous hollow structure on a cathode.)

1. A preparation method of a thermite comprises the following steps:

preparing a water solution with the concentration of 0.5-1.2 mol/L from glucose, transferring the water solution to a hydrothermal reaction kettle for hydrothermal reaction, wherein the hydrothermal reaction temperature is 160-200 ℃, and the reaction time is 6-10 hours;

centrifugally separating and drying the hydrothermal reaction product to obtain carbon sphere particles;

ultrasonically dispersing the obtained carbon sphere particles, copper nitrate and ammonia water in water to form a first suspension, wherein the mass concentration of the carbon sphere particles is 0.08-0.15 g/mL, the concentration of the copper nitrate is 0.05-0.15 mol/L, and the molar ratio of the copper nitrate to the ammonia water is (2-6): 1;

carrying out water bath aging reaction on the formed first suspension, wherein the water bath temperature is 45-55 ℃, and the aging time is 6-12 h;

centrifugally separating and drying the aging reaction product to obtain a C/Cu precursor;

calcining the obtained C/Cu precursor to obtain hollow CuO, wherein the calcining temperature is 450-600 ℃, and the calcining time is 4-8 h;

ultrasonically dispersing the obtained hollow CuO and nano aluminum powder in a mixed solution of isopropanol and Polyethyleneimine (PEI) -ethanol to form a second suspension, wherein the mass ratio of the nano aluminum powder to the CuO powder is (0.15-0.55) to 1, the total particle concentration of the nano aluminum powder and the CuO powder is 0.8-1.2g/L, the content of polyethyleneimine in a polyethyleneimine-ethanol solution is 8-12% of the total particle mass in the suspension, and the volume ratio of the mixed solution of the isopropanol and Polyethyleneimine (PEI) -ethanol is (90-110) to 1; and

and performing electrophoresis on the formed second suspension to obtain Al/CuO with a porous hollow structure through cathode deposition, wherein the electrophoresis deposition time is 5-15 min, and the applied voltage is 90-110V.

2. The method according to claim 1, wherein the distance between the anode and the cathode during electrophoretic deposition is about 0.8-1.2 cm.

3. The production method according to claim 1, wherein the temperature increase rate at the time of calcination is less than 2 ℃/min.

4. The method according to claim 1, wherein the hollow CuO has an average particle diameter of 300 to 400 nm.

5. A thermite prepared according to the method of any one of claims 1 to 4.

Technical Field

The invention relates to a thermite and a preparation method thereof.

Background

Thermite is a mixture of metal fuel (Al, Mg, etc.) and metal oxide (CuO, Fe)₂O₃NiO, etc.) under certain conditions (light, heat), a large amount of heat is released, and the composite can be widely applied to high-temperature cutting, thermite welding and energetic additives. The performance of thermites is mainly affected by the mass transfer distance between the fuel and oxidant, and researchers have currently regulated the mass transfer distance between reactant components mainly by reducing the oxide particle size. However, when the particle size of the oxide is reduced to a certain degree, agglomeration occurs between particles, and the performance of the thermite is greatly influenced.

The hollow material has good application prospect in thermite, and has the characteristics of small density, large specific surface area and the like. The hollow oxide and the aluminum powder are compounded, so that the contact area among the components can be greatly increased, and the reaction performance of the thermite is improved. At present, the synthesis of hollow materials is mainly a template method, including a soft template method and a hard template method. The hard template method has the characteristics of wider application, controllable appearance, mass production, simple synthesis method and the like.

Disclosure of Invention

The object of the present invention is to provide a process for the preparation of thermite which solves one or some of the above-mentioned drawbacks of the prior art.

According to a first aspect of the present invention, there is provided a method for preparing a thermite, comprising:

preparing a water solution with the concentration of 0.5-1.2 mol/L from glucose, transferring the water solution to a hydrothermal reaction kettle for hydrothermal reaction, wherein the hydrothermal reaction temperature is 160-200 ℃, and the reaction time is 6-10 hours;

centrifugally separating and drying the hydrothermal reaction product to obtain carbon sphere particles;

ultrasonically dispersing the obtained carbon sphere particles, copper nitrate and ammonia water in water to form a first suspension, wherein the mass concentration of the carbon sphere particles is 0.08-0.15 g/mL, the concentration of the copper nitrate is 0.05-0.15 mol/L, and the molar ratio of the copper nitrate to the ammonia water is (2-6): 1;

carrying out water bath aging reaction on the formed first suspension, wherein the water bath temperature is 45-55 ℃, and the aging time is 6-12 h;

centrifugally separating and drying the aging reaction product to obtain a C/Cu precursor;

calcining the obtained C/Cu precursor to obtain hollow CuO, wherein the calcining temperature is 450-600 ℃, and the calcining time is 4-8 h;

ultrasonically dispersing the obtained hollow CuO and nano aluminum powder in a mixed solution of isopropanol and Polyethyleneimine (PEI) -ethanol to form a second suspension, wherein the mass ratio of the nano aluminum powder to the CuO powder is (0.15-0.55) to 1, the total particle concentration of the nano aluminum powder and the CuO powder is 0.8-1.2g/L, the content of polyethyleneimine in a polyethyleneimine-ethanol solution is 8-12% of the total particle mass in the suspension, and the volume ratio of the mixed solution of the isopropanol and Polyethyleneimine (PEI) -ethanol is (90-110) to 1; and

and performing electrophoresis on the formed second suspension to obtain Al/CuO with a porous hollow structure through cathode deposition, wherein the electrophoresis deposition time is 5-15 min, and the applied voltage is 90-110V.

The preferred interval of the cathode and the anode during electrophoretic deposition is about 0.8-1.2 cm.

The rate of temperature rise during calcination is preferably less than 2 ℃/min.

The average particle size of the hollow CuO is preferably 300 to 400 nm.

Copper chloride or copper sulfate may also be used in place of copper nitrate according to the present invention.

According to a second aspect of the present invention, there is provided a thermite prepared according to the above method.

Compared with the prior art, the invention has at least the following advantages:

(1) the preparation process of the used carbon sphere (particle) template is simple and the particle size is controllable;

(2) the prepared porous hollow CuO has no impurity and the size of the CuO can be regulated and controlled by the size of the carbon spheres; and

(3) the porous hollow CuO and the nano Al can be controllably assembled through electrophoretic deposition, the performance of the porous hollow CuO and the nano Al can be adjusted, and the reactivity is high.

Drawings

Fig. 1 is an XRD pattern of a porous hollow CuO prepared according to an embodiment of the present invention;

FIG. 2 is an XRD pattern of Al/CuO having a porous hollow structure prepared in an example according to the present invention;

fig. 3 is an SEM image of porous hollow CuO prepared in an example according to the present invention;

FIG. 4 is a DSC of Al/CuO having a porous hollow structure prepared in an example according to the present invention.

Detailed Description

The invention is further illustrated by the following specific examples.

Examples

Step 1: weighing 7.00g of glucose, dissolving in 40mL of deionized water, transferring to a 100mL hydrothermal reaction kettle, reacting at 170 ℃ for 8h, taking out, washing, centrifuging, drying at 60 ℃ for 24h to obtain carbon spheres, and grinding for later use.

Step 2: weighing 3g of the carbon spheres obtained in the step 1, dissolving the carbon spheres in 25mL of deionized water, and carrying out ultrasonic treatment for 10 min; weighing 0.604g of copper nitrate, dissolving in the solution, dripping 1mL of ammonia water (0.5mol/L), and performing ultrasonic treatment for 30min to obtain a uniform suspension; aging the suspension in a water bath at 50 ℃ for 8h, taking out, washing with water, centrifuging, and drying to obtain a C/Cu precursor; and calcining the precursor at 500 ℃ for 6 hours to obtain the hollow CuO.

And step 3: weighing 0.0184g of nano aluminum powder and 0.0816g of hollow CuO (equivalent ratio is 1), adding 100mL of isopropanol and 1mL of Polyethyleneimine (PEI) -ethanol solution (mass concentration is 10g/L), performing electrophoretic deposition after ultrasonic treatment for 20min, taking a titanium sheet as a cathode and an anode, performing electrophoresis at an electrode spacing of 1cm under 100V of applied voltage, and performing deposition for 10min to obtain the porous hollow structure Al/CuO on the cathode titanium sheet.

The obtained hollow CuO and porous hollow structure Al/CuO were characterized, and the results are shown in FIGS. 1 to 4. FIG. 1 is an XRD pattern of porous hollow CuO prepared according to an example of the present invention, from which it can be seen that a diffraction peak thereof is consistent with PDF cards (#80-1916) of CuO, and the CuO has a high crystallinity. FIG. 2 is an XRD pattern of Al/CuO with a prepared porous hollow structure, wherein diffraction peaks of the Al/CuO correspond to those of Al and CuO, and no other diffraction peaks appear in a sample after compounding, which indicates that Al and CuO do not react in the compounding process. FIG. 3 is an SEM image of the porous hollow CuO, wherein the CuO is in the form of hollow spheres having a particle size of about 300 to 400 nm. FIG. 4 is a DSC chart of the prepared porous hollow structure Al/CuO, from which it can be seen that the initial exothermic temperature of the porous hollow structure Al/CuO was 554 ℃, the solid phase reaction occurred mainly, and the exothermic amount during the whole exothermic process was 1328.5J/g.