An oxygen candle with delayed start-up and stable oxygen release and its preparation method

Abstract

The present invention discloses an oxygen candle with delayed start and stable oxygen release and a preparation method thereof, which specifically relates to the technical field of chemical oxygen generation. The oxygen candle consists of an ignition layer and an oxygen generation layer. The ignition layer is composed of, by mass parts, 24-31 parts of composite fuel, 54-62 parts of oxidant, 0-8 parts of burning rate regulator, and 6-8 parts of binder; the oxygen generation layer is composed of, by mass parts, 90-94 parts of chlorate, 2-4 parts of catalyst, 0-3 parts of heat conduction material, and 1-2 parts of binder; the ignition layer can adjust the start-up time by changing the formula to achieve stable start-up, and the oxygen generation layer does not add fuel and can adjust the formula according to actual conditions to control the oxygen generation rate; the ignition layer of the oxygen candle of the present invention has high ignition reliability and good storage stability; the oxygen generation layer releases oxygen stably and has a high effective oxygen content.

Description

Technical Field

[0001] The invention belongs to the technical field of chemical oxygen generation, and in particular relates to an oxygen candle capable of delayed start and stable oxygen release and a preparation method thereof. Background Art

[0002] Oxygen candles are oxygen-generating devices that use chlorate or perchlorate as the main oxygen generator. They have the characteristics of small size, large oxygen storage capacity, and oxygen release rate and amount that are not affected by environmental conditions such as temperature, humidity and pressure. They are widely used in the initial oxygen generation devices of isolated chemical oxygen self-rescuers.

[0003] The oxygen generated by the isolated chemical oxygen self-rescuer in the initial reaction cannot meet the wearing needs, and an additional oxygen generator is needed to solve the problem of insufficient oxygen in the initial stage. At present, chemical oxygen self-rescuers widely use oxygen candle starters, but during use, fires or explosions of self-rescuers caused by oxygen candles often occur.

[0004] According to research and analysis by relevant personnel, the main reasons for the fire of chemical oxygen self-rescuer caused by oxygen candles are: ① Since a large amount of heat will be released after the oxygen candle is started, if too much fuel is added, the combustion will be extremely violent, which may cause the high-temperature burning oxygen candle powder particles to burn through the shell and cause fire; ② The combustion of oxygen generator and fuel particles in the oxygen candle is oscillating combustion. If the fuel particle size is too large or the particle size distribution is uneven, it will cause the fuel particles to aggregate and intensify the local oscillating combustion, causing the burning particles to splash and causing the self-rescuer to catch fire; ③ The oxygen candle powder block is dry-pressed or wet-pressed under a certain pressure. If the molding process is not designed properly and the oxygen candle is not strong enough, powder will be produced due to repeated wear, and the powder will be ignited by the high-temperature airflow generated by the oxygen candle and, driven by the oxygen flow, enter the rubber air pipe or airbag, causing the self-rescuer to catch fire. Summary of the invention

[0005] The invention solves the problem of insufficient safety of oxygen candle starters in chemical oxygen self-rescuer applications by providing an oxygen candle with delayed start and stable oxygen release and a preparation method thereof.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] The invention provides an oxygen candle with delayed start and stable oxygen release, comprising: an ignition layer and an oxygen generating layer located below the ignition layer; the ignition layer is formed by mixing and pressing a composite fuel, an oxidant, a burning rate regulator and a binder, and the oxygen generating layer is formed by mixing and pressing a chlorate, a catalyst, a heat conductor and a binder.

[0008] Specifically, the mass fractions of the components in the ignition layer are as follows: 24-31 parts of composite fuel, 54-62 parts of oxidant, 0-8 parts of burning rate regulator, and 6-8 parts of binder; the mass fractions of the components in the oxygen generating layer are as follows: 90-94 parts of chlorate, 2-4 parts of catalyst, 0-3 parts of thermal conductive material, and 1-2 parts of binder.

[0009] Specifically, the mass ratio of the oxidant to the composite fuel is (24-32):(13-17).

[0010] Specifically, the mass ratio of the chlorate to the catalyst is (90.5-95):(3.5-2.5).

[0011] Specifically, the particle size of the composite fuel is 300-400 mesh, the particle size of the oxidant is 200-300 mesh, the particle size of the combustion rate regulator is 300-500 mesh, and the particle size of the binder is 300-400 mesh; the particle size of the chlorate is 40-200 mesh, the laser particle size of the catalyst is 10-15 μm, and the particle size of the thermal conductive material is 300-500 mesh.

[0012] Specifically, the composite fuel is compounded from three metal powders, namely iron powder, manganese powder and cobalt powder; the oxidizer is a mixture of one or more of potassium permanganate, calcium permanganate and sodium permanganate; the burning rate regulator is one or two of calcium fluoride and boron nitride; the binder is one or more of diatomaceous earth, kaolin and clay.

[0013] Specifically, in the composite fuel, the mass ratio of manganese powder: iron powder: cobalt powder is (4-8): (6-10): (1-4).

[0014] Specifically, the chlorate is one or more of sodium chlorate, potassium chlorate, potassium perchlorate or sodium perchlorate; the catalyst is one or two of nickel-cobalt-manganese ternary composite hydroxide and nickel-cobalt-aluminum ternary composite hydroxide; the thermal conductive material is one or more of aluminum nitride, silicon carbide and boron nitride.

[0015] Furthermore, the preparation method of the oxygen candle specifically comprises the following steps:

[0016] 1) Prepare raw materials: weigh 24-31 parts of composite fuel, 54-62 parts of oxidant, 0-8 parts of burning rate regulator, 6-8 parts of binder and mix them evenly as the ignition layer raw material; weigh 90-94 parts of chlorate, 2-4 parts of catalyst, 0-3 parts of thermal conductive material, 1-2 parts of binder and mix them evenly as the oxygen generation layer raw material;

[0017] 2) Pressing and molding: First, press the oxygen-generating layer material into shape, and then add the ignition layer material to the formed oxygen-generating layer and press it into shape; the oxygen-generating layer molding pressure is 6-7T / cm3 The holding time is 2-4s; the ignition layer molding pressure is 2-4.5T / cm 3 , the holding time is 3-8s.

[0018] Furthermore, in the preparation method of the oxygen candle, the start-up time of the oxygen candle is 1-7s, and the burning speed is 0.25-0.9mm / s.

[0019] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0020] The ignition layer of the present invention adopts a time-delay design, and it takes 1 to 7 seconds from ignition to complete combustion; the ignition formula can be adjusted to control the actual start time;

[0021] The ignition layer adopts an oxygen-deficient design, and the amount of gas released at the initial stage of ignition is small; when used in an isolated chemical oxygen self-rescuer, the impact force on the self-rescuer tank and air bag is small;

[0022] The ignition layer uses composite fuel with moderate temperature. It can be normally ignited (fire cap triggered) in an environment of -10±1℃ to 60±2℃, and will not ignite when in short-term contact with open flames.

[0023] The oxygen-generating layer does not contain any fuel, is safe and reliable, and has a high effective oxygen content of 43-47w%;

[0024] The oxygen generation layer releases oxygen steadily, and the oxygen generation rate can be controlled by adjusting the formula of oxygen candles according to actual needs.

[0025] The molding process can ensure that the oxygen candle powder block has sufficient strength, eliminate or reduce the generation of powder due to repeated wear in a state of vibration and impact, and avoid danger during use. DETAILED DESCRIPTION

[0026] The present embodiment provides an oxygen candle with delayed start and smooth oxygen release and a preparation method thereof, comprising: an ignition layer and an oxygen generating layer located below the ignition layer; the ignition layer is formed by mixing and pressing a composite fuel, an oxidant, a burning rate regulator, and a binder, and the oxygen generating layer is formed by mixing and pressing a chlorate, a catalyst, a thermal conductor, and a binder.

[0027] Specifically, the mass fractions of the components in the ignition layer are as follows: 24-31 parts of composite fuel, 54-62 parts of oxidant, 0-8 parts of burning rate regulator, and 6-8 parts of binder; the mass fractions of the components in the oxygen generating layer are as follows: 90-94 parts of chlorate, 2-4 parts of catalyst, 0-3 parts of thermal conductive material, and 1-2 parts of binder.

[0028] Specifically, the mass ratio of the oxidant to the composite fuel is (24-32):(13-17).

[0029] Specifically, the mass ratio of the chlorate to the catalyst is (90.5-95):(3.5-2.5).

[0030] Specifically, the particle size of the composite fuel is 300-400 mesh, the particle size of the oxidant is 200-300 mesh, the particle size of the combustion rate regulator is 300-500 mesh, and the particle size of the binder is 300-400 mesh; the particle size of the chlorate is 40-200 mesh, the laser particle size of the catalyst is 10-15 μm, and the particle size of the thermal conductive material is 300-500 mesh.

[0031] Specifically, the composite fuel is compounded from three metal powders of iron powder, manganese powder and cobalt powder; the oxidant is a mixture of one or more of potassium permanganate, calcium permanganate and sodium permanganate; the burning rate regulator is one or two of calcium fluoride and boron nitride; the binder is one or more of diatomaceous earth, kaolin and clay;

[0032] The amount of cobalt powder added to the ignition layer can effectively adjust its combustion speed, making it release heat evenly and stably;

[0033] The permanganate in the oxidant has a low effective oxygen content, which can control the heat release of the entire ignition layer;

[0034] The calcium fluoride has poor thermal conductivity but good thermal insulation performance, while boron nitride has very high thermal conductivity, and thus adjusting the amount of calcium fluoride or boron nitride can adjust the combustion speed of the ignition layer.

[0035] Specifically, in the composite fuel, the mass ratio of manganese powder: iron powder: cobalt powder is (4-8): (6-10): (1-4).

[0036] Specifically, the chlorate is one or more of sodium chlorate, potassium chlorate, potassium perchlorate or sodium perchlorate; the catalyst is one or two of nickel-cobalt-manganese ternary composite hydroxide and nickel-cobalt-aluminum ternary composite hydroxide; the thermal conductive material is one or more of aluminum nitride, silicon carbide and boron nitride;

[0037] The application of the catalyst nickel-cobalt-manganese three-element composite hydroxide or nickel-cobalt-aluminum three-element composite hydroxide can make the oxygen generation performance of the oxygen candle equal to that of the oxygen candle with added fuel without the participation of fuel, and the oxygen release is more stable;

[0038] The heat-conducting material is an inorganic non-metallic material with high thermal conductivity. Adding it to the oxygen candle can make the heat distribution of the system more uniform to avoid excessive local temperature, and can make up for the problem of insufficient thermal conductivity of the system caused by not adding metal fuel, thereby better adjusting the combustion speed of the oxygen candle and making it burn more smoothly.

[0039] Furthermore, the preparation method of the oxygen candle specifically comprises the following steps:

[0040] 1) Prepare raw materials: weigh 24-31 parts of composite fuel, 54-62 parts of oxidant, 0-8 parts of burning rate regulator, 6-8 parts of binder and mix them evenly as the ignition layer raw material; weigh 90-94 parts of chlorate, 2-4 parts of catalyst, 0-3 parts of thermal conductive material, 1-2 parts of binder and mix them evenly as the oxygen generation layer raw material;

[0041] 2) Pressing and molding: First, press the oxygen-generating layer material into shape, and then add the ignition layer material to the formed oxygen-generating layer and press it into shape; the oxygen-generating layer molding pressure is 6-7T / cm 3 The holding time is 2-4s; the ignition layer molding pressure is 2-4.5T / cm 3 , the holding time is 3-8s.

[0042] Furthermore, in the preparation method of the oxygen candle, the start-up time of the oxygen candle is 1-7s, and the burning speed is 0.25-0.9mm / s;

[0043] Furthermore, in the preparation method of the oxygen candle, the height of the oxygen candle body after pressing and forming is 23-27 mm;

[0044] Furthermore, in the preparation method of the oxygen candle, the effective oxygen content of the oxygen candle is 43-47w%.

[0045] Here, exemplary embodiments will be described in detail. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are only examples of methods consistent with some aspects of the present invention as detailed in the appended claims.

[0046] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with embodiments.

[0047] Example 1

[0048] The present embodiment provides an oxygen candle with delayed start and smooth oxygen release, comprising: an ignition layer and an oxygen generating layer located below the ignition layer; the ignition layer is formed by mixing and pressing a composite fuel, an oxidant, a burning rate regulator, and a binder, and the oxygen generating layer is formed by mixing and pressing a chlorate, a catalyst, a thermal conductor, and a binder.

[0049] The ignition layer is 1.5 g, and the material ratio (mass fraction) is 59.5% potassium permanganate, 8.5% manganese powder, 14% iron powder, 3.5% cobalt powder, 5% boron nitride, and 7.5% kaolin.

[0050] Particle size of potassium permanganate: 200 mesh; particle size of manganese powder: 300 mesh; particle size of iron powder: 300 mesh; particle size of cobalt powder: 300 mesh; particle size of boron nitride: 400 mesh; particle size of kaolin: 300 mesh.

[0051] The oxygen-generating layer is 16.0 g, and the material ratio (mass fraction) is 83.6% sodium chlorate, 8.9% potassium perchlorate, 2% aluminum nitride, 4% nickel-cobalt-manganese composite hydroxide, and 1.5% kaolin.

[0052] Sodium chlorate particle size: 60 mesh; potassium perchlorate particle size: 200 mesh; aluminum nitride particle size: 300 mesh; nickel-cobalt-manganese ternary composite hydroxide laser particle size (D50): 13 μm; kaolin particle size: 300 mesh.

[0053] After the materials of the ignition layer and the oxygen-generating layer were dried at a constant temperature of 115°C for 2 hours, they were dry-mixed in a V-type mixer for 30 minutes to be evenly mixed;

[0054] The evenly mixed materials are loaded into the corresponding hoppers of the tablet press, with the oxygen-generating layer at the bottom and the ignition layer at the top, and pressed into tablet blocks in sequence; the molding pressure of the oxygen-generating layer is 6T / cm 3 , holding time is 3s; ignition layer molding pressure is 3T / cm 3 , the holding time is 5s.

[0055] The formed oxygen candle powder blocks were assembled into an oxygen generating device, the firing cap was pulled open, and the performance of the oxygen candle was tested: the oxygen candle starting time was 2s, the oxygen release volume was 5.4L, and the continuous oxygen release time was 58s.

[0056] Example 2

[0057] The invention provides an oxygen candle with delayed start and stable oxygen release, comprising: an ignition layer and an oxygen generating layer located below the ignition layer; the ignition layer is formed by mixing and pressing a composite fuel, an oxidant, a burning rate regulator and a binder, and the oxygen generating layer is formed by mixing and pressing a chlorate, a catalyst, a heat conductor and a binder.

[0058] The ignition layer is 1.0 g, and the material ratio (mass fraction) is 61.5% calcium permanganate, 7.5% manganese powder, 17.0% iron powder, 2.0% cobalt powder, 6.0% boron nitride, and 6.0% diatomaceous earth.

[0059] Calcium permanganate particle size: 300 mesh; manganese powder particle size: 400 mesh; iron powder particle size: 400 mesh; cobalt powder particle size: 400 mesh; boron nitride particle size: 500 mesh; diatomaceous earth particle size: 400 mesh.

[0060] The oxygen-generating layer is 15.0 g, and the material ratio (mass fraction) is 92.4% sodium chlorate, 3.3% silicon carbide, 2.5% nickel-cobalt-aluminum composite hydroxide, and 1.8% diatomaceous earth.

[0061] Sodium chlorate particle size: 80 mesh; silicon carbide particle size: 500 mesh; nickel-cobalt-aluminum ternary composite hydroxide laser particle size (D50): 15 μm; diatomaceous earth particle size: 400 mesh.

[0062] After the materials of the ignition layer and the oxygen-generating layer were dried at a constant temperature of 115°C for 2 hours, they were dry-mixed in a V-type mixer for 30 minutes to be evenly mixed;

[0063] The evenly mixed materials are loaded into the corresponding hoppers of the tablet press, with the oxygen-generating layer at the bottom and the ignition layer at the top, and pressed into tablet blocks in sequence; the molding pressure of the oxygen-generating layer is 7T / cm 3 The holding time is 4s; the ignition layer molding pressure is 4.5T / cm 3 , the holding time is 8s.

[0064] The formed oxygen candle powder blocks were assembled into an oxygen generating device, the firing cap was pulled open, and the performance of the oxygen candle was tested: the oxygen candle starting time was 5s, the oxygen release volume was 4.7L, and the continuous oxygen release time was 65s.

[0065] Example 3

[0066] The invention provides an oxygen candle with delayed start and stable oxygen release, comprising: an ignition layer and an oxygen generating layer located below the ignition layer; the ignition layer is formed by mixing and pressing a composite fuel, an oxidant, a burning rate regulator and a binder, and the oxygen generating layer is formed by mixing and pressing a chlorate, a catalyst, a heat conductor and a binder.

[0067] The ignition layer is 2.0 g, and the material ratio (mass fraction) is 60.0% sodium permanganate, 11.0% manganese powder, 13.5% iron powder, 5.5% cobalt powder, 5.0% calcium fluoride, and 5.0% kaolin.

[0068] Sodium permanganate particle size: 200 mesh; manganese powder particle size: 300 mesh; iron powder particle size: 300 mesh; cobalt powder particle size: 300 mesh; calcium fluoride particle size: 300 mesh; kaolin particle size: 300 mesh.

[0069] The oxygen-generating layer is 17.0 g, and the material ratio (mass fraction) is 89.2% sodium chlorate, 4.6% sodium perchlorate, 2.3% boron nitride, 2.8% nickel-cobalt-aluminum composite hydroxide, and 1.1% kaolin.

[0070] Sodium chlorate particle size: 40 mesh; sodium perchlorate: 200 mesh; boron nitride particle size: 400 mesh; nickel-cobalt-aluminum ternary composite hydroxide laser particle size (D50): 10 μm; kaolin particle size: 300 mesh.

[0071] After the materials of the ignition layer and the oxygen-generating layer were dried at a constant temperature of 115°C for 2 hours, they were dry-mixed in a V-type mixer for 30 minutes to be evenly mixed;

[0072] The evenly mixed materials are loaded into the corresponding hoppers of the tablet press, with the oxygen-generating layer at the bottom and the ignition layer at the top, and pressed into tablet blocks in sequence; the molding pressure of the oxygen-generating layer is 5T / cm 3 , holding time is 3s; ignition layer molding pressure is 3T / cm 3, the holding time is 5s.

[0073] The formed oxygen candle powder blocks were assembled into an oxygen generating device, the firing cap was pulled open, and the performance of the oxygen candle was tested: the oxygen candle starting time was 1 second, the oxygen release volume was 5.8L, and the continuous oxygen release time was 75 seconds.

[0074] Example 4

[0075] The invention provides an oxygen candle with delayed start and stable oxygen release, comprising: an ignition layer and an oxygen generating layer located below the ignition layer; the ignition layer is formed by mixing and pressing a composite fuel, an oxidant, a burning rate regulator and a binder, and the oxygen generating layer is formed by mixing and pressing a chlorate, a catalyst, a heat conductor and a binder.

[0076] The ignition layer is 1.5 g, and the material ratio (mass fraction) is 57.5% calcium permanganate, 12.0% manganese powder, 15.0% iron powder, 2.0% cobalt powder, 7.5% boron nitride, and 6.0% diatomaceous earth.

[0077] Calcium permanganate particle size: 200 mesh; manganese powder particle size: 400 mesh; iron powder particle size: 400 mesh; cobalt powder particle size: 300 mesh; boron nitride particle size: 500 mesh; diatomaceous earth particle size: 400 mesh.

[0078] The oxygen-generating layer is 16.5 g, and the material ratio (mass fraction) is 83.7% potassium chlorate, 8.4% potassium perchlorate, 2.9% aluminum nitride, 3.3% nickel-cobalt-manganese composite hydroxide, and 1.7% diatomaceous earth.

[0079] Potassium chlorate particle size: 200 mesh; potassium perchlorate: 200 mesh; aluminum nitride particle size: 300 mesh; nickel-cobalt-manganese ternary composite hydroxide laser particle size (D50): 15 μm; diatomaceous earth particle size: 400 mesh.

[0080] After the materials of the ignition layer and the oxygen-generating layer were dried at a constant temperature of 115°C for 2 hours, they were dry-mixed in a V-type mixer for 30 minutes to be evenly mixed;

[0081] The evenly mixed materials are loaded into the corresponding hoppers of the tablet press, with the oxygen-generating layer at the bottom and the ignition layer at the top, and pressed into tablet blocks in sequence; the molding pressure of the oxygen-generating layer is 7T / cm 3 The holding time is 4s; the ignition layer molding pressure is 4.5T / cm 3 , the holding time is 8s.

[0082] The formed oxygen candle powder blocks were assembled into an oxygen generating device, the firing cap was pulled open, and the performance of the oxygen candle was tested: the oxygen candle starting time was 5s, the oxygen release volume was 5.6L, and the continuous oxygen release time was 55s.

[0083] Example 5

[0084] On the basis of Examples 1-4, this Example further provides a method for preparing an oxygen candle with delayed start and stable oxygen release, which specifically comprises the following steps:

[0085] 1) Prepare raw materials: weigh 24-31 parts of composite fuel, 54-62 parts of oxidant, 0-8 parts of burning rate regulator, 6-8 parts of binder and mix them evenly as the ignition layer raw material; weigh 90-94 parts of chlorate, 2-4 parts of catalyst, 0-3 parts of thermal conductive material, 1-2 parts of binder and mix them evenly as the oxygen generation layer raw material;

[0086] 2) Pressing and molding: First, press the oxygen-generating layer material into shape, and then add the ignition layer material to the formed oxygen-generating layer and press it into shape; the oxygen-generating layer molding pressure is 6-7T / cm 3 The holding time is 2-4s; the ignition layer molding pressure is 2-4.5T / cm 3 , the holding time is 3-8s.

[0087] The above description is only a specific embodiment of the present invention, so that those skilled in the art can understand or implement the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention.

[0088] It should be understood that the present invention is not limited to what has been described above and that various modifications and changes may be made without departing from its scope. The scope of the present invention is limited only by the appended claims.

Claims

1. An oxygen candle with delayed start and stable oxygen release, Characterized in that, It includes: An ignition layer and an oxygen generation layer located below the ignition layer; the ignition layer is made by mixing and pressing a composite fuel, an oxidizer, a burning rate regulator, and a binder, and the oxygen generation layer is made by mixing and pressing a chlorate, a catalyst, a heat-conducting material, and a binder; The mass parts of each component in the ignition layer are as follows: 24 - 31 parts of composite fuel, 54 - 62 parts of oxidizer, 0 - 8 parts of burning rate regulator, 6 - 8 parts of binder, wherein the mass parts of the burning rate regulator are not zero; the mass parts of each component in the oxygen generation layer are as follows: 90 - 94 parts of chlorate, 2 - 4 parts of catalyst, 0 - 3 parts of heat-conducting material, 1 - 2 parts of binder, wherein the mass parts of the heat-conducting material are not zero; The composite fuel is composed of a compound of three metal powders of iron powder, manganese powder, and cobalt powder; the oxidizer is one or a mixture of potassium permanganate, calcium permanganate, and sodium permanganate; the burning rate regulator is one or two of calcium fluoride and boron nitride; the binder is one or a mixture of diatomite, kaolin, and pottery clay; The chlorate is one or more of sodium chlorate, potassium chlorate, potassium perchlorate, or sodium perchlorate; the catalyst is one or two of nickel-cobalt-manganese ternary composite hydroxide and nickel-cobalt-aluminum ternary composite hydroxide; the heat-conducting material is one or more of aluminum nitride, silicon carbide, and boron nitride.

2. The oxygen candle according to claim 1, Characterized in that, The mass ratio of the oxidizer to the composite fuel is (24 - 32):(13 - 17).

3. The oxygen candle according to claim 1, Characterized in that, The mass ratio of the chlorate to the catalyst is (90.5 - 95):(3.5 - 2.5).

4. The oxygen candle according to claim 1, Characterized in that, The particle size of the composite fuel is 300 - 400 mesh, the particle size of the oxidizer is 200 - 300 mesh, the particle size of the burning rate regulator is 300 - 500 mesh, and the particle size of the binder is 300 - 400 mesh; the particle size of the chlorate is 40 - 200 mesh, the laser particle size of the catalyst is 10 - 15 μm, and the particle size of the heat-conducting material is 300 - 500 mesh.

5. The oxygen candle according to claim 1, Characterized in that, In the composite fuel, the mass ratio of manganese powder:iron powder:cobalt powder is (4 - 8):(6 - 10):(1 - 4).

6. The preparation method of the oxygen candle according to any one of claims 1 - 5, Characterized in that, Specifically includes the following steps: 1) Prepare raw materials: Weigh 24 - 31 parts of composite fuel, 54 - 62 parts of oxidizer, 0 - 8 parts of burning rate regulator, and 6 - 8 parts of binder according to mass parts and mix them evenly as the raw materials for the ignition layer, wherein the mass parts of the burning rate regulator are not zero; weigh 90 - 94 parts of chlorate, 2 - 4 parts of catalyst, 0 - 3 parts of heat-conducting material, and 1 - 2 parts of binder and mix them evenly as the raw materials for the oxygen generation layer, wherein the mass parts of the heat-conducting material are not zero; 2) Compression molding: First, compress the oxygen - generating layer material into a shape, and then add the ignition layer material on the basis of the formed oxygen - generating layer and compress it into a shape; among them, the forming pressure of the oxygen - generating layer is 6 - 7 T / cm 3 , and the pressure - holding time is 2 - 4 s; the forming pressure of the ignition layer is 2 - 4.5 T / cm 3 , and the pressure - holding time is 3 - 8 s.

7. The preparation method of the oxygen candle according to claim 6, Characterized in that, The starting time of the oxygen candle is 1 - 7 s, and the burning rate is 0.25 - 0.9 mm / s.