Microchannel continuous flow preparation method for liquid phase carrier of melt-cast explosive

Abstract

The present invention discloses a microchannel continuous flow method for preparing a liquid phase carrier for molten-cast explosives. The method utilizes multiple microchannel reactors connected in series, rapidly mixing an anisole derivative reaction solution and a nitrating agent to which a surfactant is added in proportion in the microchannel reactors, and then maintaining the mixture under certain temperature conditions for a period of time to complete the reaction, thereby obtaining a mixed acid solution containing the product. After cooling, the mixture is quenched and crystallized, and filtered and dried to obtain the liquid phase carrier for molten-cast explosives. The method has the advantages of improving the mixing efficiency between the liquid phase carrier raw material, intermediate, product oil phase, and nitrating agent aqueous phase during the heating reaction by using a surfactant, thereby improving the reaction yield, increasing product purity, and reducing the reaction time. With a retention time of approximately 3 to 15 minutes, the product purity is greater than 99%, and the product yield is as high as 97%.

Description

Technical Field

[0001] The invention relates to a method for preparing energetic materials, in particular to a microchannel continuous flow preparation method for a novel liquid phase carrier of melt-cast explosives. Background Art

[0002] Compared with toluene-based chemical reagents, anisole-based derivatives have the characteristics of low toxicity and low cost. Therefore, they are often used as raw materials to prepare liquid phase carriers for melt-cast explosives. For example, 2,4-dinitroanisole (DNAN) is used to replace the more toxic 2,4,6-trinitrotoluene (TNT). However, the density and energy of DNAN (density of 1.54g / cm 3 , with a detonation velocity of 5590m / s) is relatively low and cannot meet the needs of advanced weapon applications. In recent years, the emergence of 3-bromo-2,4,6-trinitroanisole (TNBA) and 3,5-difluoro-2,4,6-trinitroanisole (TNDFA) has attracted more attention to liquid phase carriers of anisole-derived melt-cast explosives. By introducing halogens to adjust the structure-activity relationship between the melting point and energy properties of 2,4,6-trinitroanisole, a density greater than 1.8g / cm 3 , a new type of liquid phase carrier for melt-cast explosives with an impact sensitivity greater than 40J and a friction sensitivity greater than 240N, the structural formula of which is as follows:

[0003]

[0004] In 2021, the Xi'an Institute of Modern Chemistry reported a kettle synthesis method for TNBA (Journal of Explosives and Propellants 2021, 44(4): 441-446). The synthesis route is as follows:

[0005]

[0006] This route uses 20% oleum / fuming nitric acid / ethylene dichloride, 20% oleum / concentrated sulfuric acid / fuming nitric acid, and 20% oleum / fuming nitric acid as the nitration system. However, this autoclave reaction still requires high-temperature nitration and a relatively complex separation method, which brings high safety risks and operational difficulties to the batch preparation of this compound.

[0007] In 2022, North University of China reported a kettle synthesis method for TNDFA (reference J.Energ.Mater.2022,40(2):206-217), and its synthesis route is as follows:

[0008]

[0009] The literature reports that nitration of TNDFA is performed using a 100% nitric acid / 100% sulfuric acid system at a high kettle temperature of 98°C, followed by fluorination using NaF and DMSO. This process not only increases the number of steps and reaction time, but also complicates the operation and increases safety risks.

[0010] In recent years, microchannel continuous flow synthesis technology has gradually become a leader in the chemical industry, not only because it significantly reduces safety risks, but also because it offers advantages such as uniform mixing, rapid mass and heat transfer, strong reaction selectivity, a small reaction space, no amplification effect, and continuous production. To date, there are no reports of using microchannel reactors to prepare the liquid phase carrier for molten-cast explosives mentioned in this patent. Therefore, it is necessary to develop a new method for preparing new liquid phase carriers for molten-cast explosives using channel-type continuous flow to significantly improve the safety and efficiency of the preparation process. Summary of the Invention

[0011] The object of the present invention is to provide a continuous, highly safe and efficient channel-type continuous flow preparation method for a novel liquid phase carrier for melt-cast explosives synthesized from anisole derivatives. The general structure is as follows:

[0012]

[0013] The strong acid-resistant alkyl quaternary ammonium salt phase transfer catalyst (i.e., surfactant) used in the present invention has the following general structure:

[0014] In a specific embodiment, the surfactants that can be selected include, but are not limited to, cetyltrimethylammonium bromide, cetyltrimethylammonium fluoride, and cetyltrimethylammonium chloride.

[0015] The microchannel continuous flow preparation method of the liquid phase carrier of the molten-cast explosive utilizes multiple microchannel reactors connected in series, and the anisole derivative reaction solution and the nitrating agent with the addition of a surfactant are rapidly mixed in a microchannel reactor in proportion, and the mixture is kept at a certain temperature for a period of time to complete the reaction, thereby obtaining a mixed acid solution containing the product. After cooling, the mixture is quenched and crystallized, and filtered and dried to obtain the liquid phase carrier of the molten-cast explosive. Figure 4 shown.

[0016] The microchannel continuous flow preparation method for the liquid phase carrier of the molten-cast explosive comprises the following specific steps:

[0017] (1) Raw material preparation: An anisole derivative is prepared into a homogeneous raw material solution A; fuming nitric acid or a nitrate is added to concentrated sulfuric acid or 20% fuming sulfuric acid at room temperature or in an ice-water bath, and the temperature is maintained or heated while continuously stirring until a homogeneous solution is obtained, i.e., the nitrating agent. A certain amount of surfactant is then added to prepare raw material solution B;

[0018] (2) Reaction process: The process temperature of the microchannel reactor is controlled at above 80°C, and the feed flow rate of the raw material liquid A and the raw material liquid B is controlled by the feed pump to control the materials to enter the reactor according to the ratio. The materials are retained under the process temperature conditions for a period of time until the nitration reaction is completed, and a mixed acid solution containing the product is obtained;

[0019] (3) Reaction quenching: The mixed acid solution containing the product is cooled and diluted with water for crystallization under temperature-controlled conditions, and then filtered and dried to obtain the liquid phase carrier of the melt-cast explosive.

[0020] In the above preparation method, the channel diameter of each microchannel reactor is 0.1-10 mm, and the liquid holdup is ≥6 mL; the number of microchannel reactors connected in series is ≥3; the nitrating agent is selected from one of fuming nitric acid / concentrated sulfuric acid, fuming nitric acid / 20% fuming sulfuric acid, sodium nitrate / concentrated sulfuric acid, potassium nitrate / concentrated sulfuric acid, and ammonium nitrate / concentrated sulfuric acid; and the molar ratio of nitronium ion to anisole derivative entering the microchannel reactor is 3-20. During the reaction process.

[0021] During the reaction, the process temperature range is 80-150° C., and the retention time is 1-20 minutes.

[0022] The molar ratio of the surfactant to the nitrating agent is 1:50 to 1:350.

[0023] During the quenching process, the temperature control conditions are as follows: the material temperature is ≤25°C, and the volume ratio of the mixed acid solution containing the product to water is 1:1 to 1:30.

[0024] The technical solution of the present invention is further described below:

[0025] 1) A homogeneous nitrating agent solution is prepared to achieve continuous sampling of the material. The nitrating agent used is one of 65-70% HNO3 / concentrated H2SO4, fuming HNO3 / concentrated H2SO4, fuming HNO3 / 20% fuming H2SO4, NaNO3 / concentrated H2SO4, KNO3 / concentrated H2SO4, and NH4NO3 / concentrated H2SO4. The term "65-70% HNO3 / concentrated H2SO4" refers to a nitrating agent solution composed of 65-70% HNO3 and concentrated H2SO4, where 65-70% is the mass fraction. The same applies to fuming HNO3 / concentrated H2SO4, fuming HNO3 / 20% fuming H2SO4, NaNO3 / concentrated H2SO4, KNO3 / concentrated H2SO4, and NH4NO3 / concentrated H2SO4.

[0026] 2) using a feed pump to feed the material into the reactor at a molar ratio of nitronium ion to anisole derivative of 3 to 20:1 to ensure that the material reaction concentration is compatible;

[0027] 3) Utilizing the advantages of low material loading, strong heat exchange efficiency and strong mixing and mass transfer efficiency of microchannel reactors (channel diameter 0.1-10mm) to achieve rapid material mixing, efficient heat exchange and reaction process intensification, thereby effectively ensuring the safety of the nitration process;

[0028] 4) Using a higher reaction temperature (80-120°C) can greatly accelerate the reaction rate (reaction time is 3-15 minutes), thereby improving the reaction efficiency and shortening the reaction time.

[0029] 5) The mixture of fuming HNO3 or nitrate and concentrated H2SO4 or 20% fuming H2SO4 is referred to as "nitric-sulfuric acid mixture". Unless otherwise specified, the "%" in the present invention regarding the content is mass fraction.

[0030] 6) During the reaction, the reaction mixture is retained at the process temperature for 1 to 20 minutes, preferably 3 to 15 minutes. The holding time needs to match the reactor throughput and adjust the total material flow rate to meet the sufficient retention time requirement. The anisole derivative can be any one of 3-bromoanisole, 3-fluoroanisole, 3,5-difluoroanisole, 3-fluoro-5-bromoanisole, and 3,5-dibromoanisole.

[0031] Compared with the prior art, the present invention has the following beneficial effects: Compared with previously reported preparation methods, the novel channel-type continuous flow preparation method for a liquid phase carrier for melt-cast explosives provided by the present invention improves the mixing efficiency between the liquid phase carrier raw material, intermediate, product oil phase, and nitrating reagent aqueous phase during the heating reaction by using a surfactant, thereby improving the reaction yield, enhancing product purity, and reducing reaction time. With a retention time of approximately 3 to 15 minutes, the product purity is greater than 99%, and the product yield is as high as 97%. Compared with kettle-type preparation methods, the provided preparation method significantly improves the reaction mixing efficiency, significantly increasing the reaction yield and purity. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is a single crystal structure diagram of 3-fluoro-2,4,6-trinitroanisole of the present invention;

[0033] Figure 2 3-Fluoro-5-bromo-2,4,6-trinitroanisole in the present invention;

[0034] Figure 3 This is a single crystal structure diagram of 3,5-dibromo-2,4,6-trinitroanisole in the present invention.

[0035] Figure 4 The figure is a reaction flow chart of the present invention. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0037] Example 1:

[0038] 10g 3-bromoanisole is placed sampling bottle stand-by as solution A, under ice bath condition, 65%~70% nitric acid 56g that will be dissolved with surfactant hexadecyltrimethylammonium bromide is mixed with settled solution B (surfactant and nitric acid mol ratio is 1:205), regulating thermostat temperature micro passage reactor (channel diameter 1mm) jacket temperature is set to 90 ℃, by constant flow pump respectively with A and B according to the proportioning injection of nitronium ion and anisole derivative mol ratio=5 in 3 micro passage reactors (every liquid holdup is 6mL) of series connection, retention time is 5min; Reaction solution is quenched with 1 volume of frozen water, separates out solid, and after the filtration washing dry, product yield 7%, purity are 56.5%.

[0039] Example 2:

[0040] 10g 3-fluoroanisole is placed in a sampling bottle and is stand-by as solution A, 98% fuming HNO3 56g will be dissolved with a surfactant hexadecyltrimethylammonium fluoride under ice bath condition and is placed in a bottle and is stand-by as solution B (the mol ratio of surfactant and nitric acid is 1:105); Regulating thermostat temperature to control micro passage reactor (channel diameter 1mm) jacket temperature is 90 ℃, by advection pump respectively with A and B according to the proportioning injection of nitronium ion and anisole derivative=6.0 in 3 micro passage reactors (every liquid holdup is 6mL) in series, retention time is 5min; With the reaction solution quenched with 3 volumes of frozen water, separate out solid, after filtering, washing and drying, product yield 11%, purity is 71.9%.

[0041] Example 3:

[0042] 10g of 3,5-difluoroanisole was placed in a sampling bottle for use as solution A, and a total of 56g of a 98% fuming HNO3 / concentrated H2SO4 mixed solution dissolved with a surfactant, cetyltrimethylammonium fluoride, was prepared as a clear solution B under ice bath conditions (the molar ratio of surfactant to nitric-sulfuric acid was 1:75). The temperature was maintained and stirring was continued during the preparation process (the same as in Examples 4 to 12); the jacket temperature of a microchannel reactor (channel diameter 1mm) was controlled to 90°C by adjusting the thermostat, and A and B were respectively sampled into 5 microchannel reactors connected in series (each holding capacity was 6mL) in a ratio of nitronium ion to anisole derivative of 6.0 by a horizontal flow pump, with a retention time of 11min; the reaction solution was quenched with 4 volumes of ice water to precipitate a solid, which was filtered, washed, and dried to give a product yield of 94% with a purity of 99.2%.

[0043] Example 4:

[0044] 10g 3-fluoro-5-bromoanisole is placed sampling bottle stand-by as solution A, will be dissolved with 98% fuming HNO of surfactant cetyltrimethylammonium bromide under ice bath condition / 20% fuming H SO Mixed solutions 56g is mixed with settled solution B (mol ratio of surfactant and nitric-sulfur mixed acid is 1:65); Regulating thermostat temperature control micro passage reactor (channel diameter 1mm) jacket temperature is 90 ℃, by advection pump respectively with A and B according to the proportioning injection of nitronium ion and anisole derivative=6.0 in 5 micro passage reactors (every liquid holdup is 6mL) in series, retention time is 15min; Reaction solution is quenched with 5 volumes of frozen water, separated out solid, after filtration, washing and drying, product yield 88%, purity are 99.1%.

[0045] Example 5:

[0046] 10 g of 3,5-dibromoanisole was placed in an injection bottle and heated until dissolved to form a clear solution A; 76 g of NaNO3 was dissolved in concentrated H2SO4, heated to a clear solution, and then cooled to room temperature to form solution B, to which the surfactant cetyltrimethylammonium bromide was subsequently added (the molar ratio of the surfactant to the mixed solution of sodium nitrate and sulfuric acid was 1:75); the temperature of the jacket of a microchannel reactor (channel diameter 1 mm) was controlled by adjusting the thermostat to 120°C, and A and B were respectively injected into five microchannel reactors connected in series (each with a liquid holding capacity of 6 mL) using a constant flow pump in a ratio of nitronium ion to anisole derivative = 20, with a retention time of 5 minutes; the reaction solution was quenched with 15 volumes of ice water to precipitate a solid, which was filtered, washed, and dried. The product yield was 92% and the purity was 99.3%.

[0047] Example 6:

[0048] 10g 3-fluoro-5-bromoanisole is placed in sampling bottle stand-by for solution A, under normal temperature condition with KNO 90g is dissolved in dense H SO In be mixed with settled solution B, subsequently surfactant cetyl trimethylammonium bromide is added wherein (mol ratio of surfactant and saltpetre, sulfuric acid mixing solution is 1:75); Regulating thermostat temperature control micro passage reactor (channel diameter 1mm) jacket temperature is 90 ℃, by constant flow pump respectively with A and B according to the proportioning injection of nitronium ion and anisole derivative=5.0 in the micro passage reactor (every liquid holdup is 6mL) of 5 series connection, retention time is 5min; Reaction solution is quenched with 6 volume frozen water, separated out solid, after filtration washing drying, product yield 91%, purity are 99.5%.

[0049] Example 7:

[0050] 10g 3-bromoanisole is placed in a sampling bottle for stand-by use as solution A, and under ice bath condition, KNO3 71g is dissolved in concentrated H2SO4 in to prepare clear solution B, and subsequently surfactant cetyltrimethylammonium bromide is added thereto (the mol ratio of surfactant to potassium nitrate and sulfuric acid mixed solution is 1:105); It is 80 ℃ to regulate the temperature of the thermostat temperature control microchannel reactor (channel diameter 1mm) jacket temperature, and A and B are respectively sampled into 3 microchannel reactors (each liquid holdup is 6mL) in series connection according to the ratio of nitronium ion and anisole derivative=6.0 by a constant flow pump, and the retention time is 5min; The reaction solution is quenched with 8 volumes of frozen water, and a solid is separated out. After filtering, washing and drying, the product yield is 76%, and the purity is 97.5%.

[0051] Example 8:

[0052] 10g 3-fluoroanisole is placed in a sampling bottle for use as solution A, and at normal temperature, KNO3 42g is dissolved in concentrated H2SO4 in to prepare clear solution B, subsequently surfactant hexadecyltrimethylammonium fluoride is added thereto (the mol ratio of surfactant to saltpetre and sulfuric acid mixed solution is 1:75); Regulating thermostat temperature to control microchannel reactor (channel diameter 1mm) jacket temperature is 80 ℃, and by constant flow pump, A and B are respectively sampled into 5 microchannel reactors (each liquid holdup is 6mL) in series according to the proportioning of nitronium ion and anisole derivative=3.5, and retention time is 10min; The reaction solution is quenched with 30 volumes of frozen water, and solid is separated out. After filtering, washing and drying, the product yield is 83%, and purity is 98.3%.

[0053] Example 9:

[0054] 10 g of 3,5-difluoroanisole was placed in a sampling bottle for use as solution A, 180 g of KNO3 was dissolved in concentrated H2SO4 at room temperature to prepare a clear solution B, and then cetyltrimethylammonium fluoride, a surfactant, was added thereto (the molar ratio of the surfactant to a mixed solution of potassium nitrate and sulfuric acid was 1:65); the jacket temperature of a microchannel reactor (channel diameter 1 mm) was controlled to 100° C. by adjusting a thermostat, and A and B were respectively introduced into five microchannel reactors connected in series (each with a liquid holdup of 6 mL) using a constant flow pump at a molar ratio of nitronium ion to anisole derivative of 3.5, with a retention time of 5 min; the reaction solution was quenched with 4 volumes of ice water to precipitate a solid, which was filtered, washed, and dried to obtain a product yield of 97% and a purity of 99.6%.

[0055] Example 10:

[0056] 10g of 3-bromoanisole was placed in a sampling bottle for use as solution A, and 71g of NH4NO3 was dissolved in concentrated H2SO4 under ice bath condition to prepare clear solution B, and subsequently surfactant cetyltrimethylammonium bromide was added thereto (the mol ratio of surfactant to ammonium nitrate and sulfuric acid mixed solution was 1:105); the jacket temperature of the microchannel reactor (channel diameter 1mm) was regulated to 80°C by a thermostat, and A and B were respectively sampled into three microchannel reactors (each holdup was 6mL) connected in series according to a ratio of nitronium ion to anisole derivative of 6.0 by a constant flow pump, with a retention time of 8min; the reaction solution was quenched with 4 volumes of ice water to separate out a solid, which was filtered, washed, and dried to give a product yield of 74% and a purity of 98.1%.

[0057] Example 11:

[0058] 10 g of 3-fluoroanisole was placed in a sampling bottle for use as solution A, 71 g of NH4NO3 was dissolved in concentrated H2SO4 under ice bath conditions to prepare a clear solution B, and subsequently cetyltrimethylammonium chloride, a surfactant, was added thereto (the molar ratio of the surfactant to the ammonium nitrate and sulfuric acid mixed solution was 1:75); the jacket temperature of a microchannel reactor (channel diameter 1 mm) was adjusted to 90° C. using a thermostat, and A and B were respectively sampled into five microchannel reactors (each holding capacity was 6 mL) connected in series using a constant flow pump at a ratio of nitronium ion to anisole derivative of 4.0, with a retention time of 15 min; the reaction solution was quenched with 10 volumes of ice water to separate out a solid, which was filtered, washed, and dried to give a product yield of 89% and a purity of 99.2%.

[0059] Example 12:

[0060] 10 g of 3,5-difluoroanisole was placed in a sampling bottle for use as solution A. 71 g of NH₄NO₃ was dissolved in concentrated H₂SO₄ in an ice bath to prepare a clear solution B. Subsequently, a surfactant, cetyltrimethylammonium chloride, was added thereto (the molar ratio of the surfactant to the ammonium nitrate and sulfuric acid mixed solution was 1:65). The jacket temperature of a microchannel reactor (channel diameter 1 mm) was controlled to 120° C. by adjusting a thermostat. A and B were respectively introduced into five microchannel reactors connected in series (each with a liquid holdup of 6 mL) using a constant flow pump in a ratio of nitronium ion to anisole derivative of 4.0. The retention time was 12 min. The reaction solution was quenched with 4 volumes of ice water to precipitate a solid, which was filtered, washed, and dried to obtain a product with a yield of 95% and a purity of 99.5%.

[0061] The single crystal structures of 3-fluoro-2,4,6-trinitroanisole in Cases 2, 8, and 11 are as follows: Figure 1 The solvent compound is in the P 21 / n space group, with unit cell parameters of a=17.768(7), b=6.029(2), c=19.022(7), α=90, β=107.719(12), γ=90; and a crystal density of 1.815 g / cm 3 (UK Cambridge Database CCDC No.: 2269030).

[0062] The single crystal structures of 3-fluoro-5-bromo-2,4,6-trinitroanisole in Cases 4 and 6 are shown in Figure 2 The compound is in the P 21 21 21 space group, with unit cell parameters of a = 6.6547 (2), b = 9.5248 (3), c = 13.7904 (4), α = 90, β = 90, γ = 90; and a crystal density of 1.970 g / cm 3 (UK Cambridge Database CCDC No.: 2269031).

[0063] The single crystal structure of 3,5-dibromo-2,4,6-trinitroanisole in Case 5 is as follows Figure 3 The compound is in the P21 21 21 space group, with unit cell parameters of a = 6.6547 (2), b = 9.5248 (3), c = 13.7904 (4), α = 90, β = 90, γ = 90; and a crystal density of 2.149 g / cm 3 (UK Cambridge Database CCDC No.: 2269032).

[0064] Although the present invention has been described herein with reference to illustrative embodiments of the present invention, it will be appreciated that those skilled in the art may devise numerous other modifications and implementations that fall within the scope and spirit of the principles disclosed herein. More specifically, within the scope disclosed herein, various variations and improvements may be made to the components and / or layout of the subject combination layout. In addition to variations and improvements made to the components and / or layout, other uses will be apparent to those skilled in the art.

Claims

1. A microchannel continuous flow method for preparing a liquid phase carrier of a melt-cast explosive, characterized in that: The method utilizes multiple microchannel reactors connected in series, rapidly mixing an anisole derivative reaction solution and a nitrating agent added with a surfactant in a proportion in the microchannel reactor, and maintaining the mixture at a temperature of 80 to 150° C. for 3 to 15 minutes to complete the reaction, thereby obtaining a mixed acid solution containing a product. After cooling, the solution is quenched and crystallized, and filtered and dried to obtain a liquid phase carrier for melt-cast explosives. The surfactant chemical formula is (CH3)3NC n H 2n+1 X, n=12, 14, 16 or 18, X=F, Cl, Br or I; The molar ratio of the surfactant to the nitrating agent is 1:65 to 1:

75.

2. The microchannel continuous flow preparation method for the liquid phase carrier of molten-cast explosive according to claim 1, characterized in that: The specific steps are as follows: (1) Raw material preparation: Anisole derivatives are prepared into a homogeneous raw material solution A; fuming nitric acid or nitrate is added to concentrated sulfuric acid or 20% fuming sulfuric acid at room temperature or in an ice-water bath, and the temperature is maintained or heated while continuously stirring until a homogeneous solution is obtained, which is the nitrating agent. A certain amount of surfactant is then added to prepare raw material solution B; (2) Reaction process: The process temperature of the microchannel reactor is controlled at 80 o C or above, the feed flow rate of the raw material liquid A and the raw material liquid B is controlled by the feed pump to control the materials to enter the reactor according to the ratio, and they are retained for a period of time under the process temperature conditions until the nitration reaction is completed to obtain a mixed acid solution containing the product; (3) Reaction quenching: The mixed acid solution containing the product is cooled and diluted with water for crystallization under temperature-controlled conditions, and then filtered and dried to obtain the liquid phase carrier of the melt-cast explosive.

3. The microchannel continuous flow preparation method for the liquid phase carrier of molten-cast explosive according to claim 1, characterized in that: The channel diameter of each microchannel reactor is 0.1-10 mm, and the liquid holding capacity is ≥6 mL.

4. The microchannel continuous flow preparation method for the liquid phase carrier of molten-cast explosive according to claim 1, characterized in that: The number of the microchannel reactors connected in series is ≥3.

5. The microchannel continuous flow preparation method for a liquid phase carrier of molten-cast explosive according to claim 1 or 2, characterized in that: The nitrating agent is selected from one of fuming nitric acid / concentrated sulfuric acid, fuming nitric acid / 20% fuming sulfuric acid, sodium nitrate / concentrated sulfuric acid, potassium nitrate / concentrated sulfuric acid, and ammonium nitrate / concentrated sulfuric acid.

6. The microchannel continuous flow preparation method for the liquid phase carrier of molten-cast explosive according to claim 2, characterized in that: The molar ratio of the nitronium ion to the anisole derivative entering the microchannel reactor is 3-20.

7. The microchannel continuous flow preparation method for a liquid phase carrier of molten-cast explosive according to claim 2, characterized in that: During the quenching process, the temperature control conditions are as follows: the material temperature is ≤25°C, and the volume ratio of the mixed acid solution containing the product to water is 1:1~1:30.

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