63 results about "Ammonium dinitramide" patented technology

Nondetonable, or low detonation sensitivity, substantially nontoxic liquid monopropellants are provided. The liquid propellants are formed from aqueous solutions of solid oxidizers in liquid oxidizers and water soluble liquid fuels and formulated to have a freezing point less than −10° C. Liquid oxidizers may be inorganic or organic aqueous solutions, with hydrogen peroxide being preferred. Preferred solid oxidizers are water soluble nitrates including ammonium dinitramide, aminoguanidine dinitrate, ammonium nitrate, hydroxylamine nitrate, hydrazine nitrate, guanidine nitrate and aminoguanidine nitrate. Preferred liquid fuels are water soluble alcohols, amines and amine nitrates, hydroxyethyl hydrazine, hydroxyethylhydrazine nitrate, cyanoguanidine, guanidines, aminoguanidines, triaminoguanidines, and their nitrate salts, ethanolamine dinitrate, ethylenediamine dinitrate, polyvinyl nitrate, and aziridine.

The present invention relates to a reactor for the decomposition of ammonium dinitramide-based liquid monopropellants into hot, combustible gases for combustion in a combustion chamber, and more particularly a rocket engine or thruster comprising such reactor and a combustion chamber. The invention also relates to a process for the decompostion of ammonium dinitramide-based liquid monopropellants.

The present invention relates to a reactor for the decomposition of ammonium dinitramide-based liquid monopropellants into hot, combustible gases for combustion in a combustion chamber, and more particularly a rocket engine or thruster comprising such reactor and a combustion chamber. The invention also relates to a process for the decompostion of ammonium dinitramide-based liquid monopropellants.

Ammonium dinitramide based liquid monopropellants exhibiting stabilised combustion characteristics and improved storage life, containing ammonia, a base weaker than ammonia, or a base which is sterically hindered, added in an amount of 0.1 to 5% of the total weight of the other components of the propellant.

The invention discloses a high-energy-density explosive mixture. A low-melting-point single-compound explosive is adopted and comprises, by mass, 5-30% of an adhesive, 15-60% of a main explosive, 15-40% of a combustion agent, 0-25% of an oxidizing agent and 5-50% of a high-density high-energy additive, wherein the adhesive is prepared from trinitrotoluene, 2,4-dimitroanisole and 3,4-dinitrofurazanofuroxan, the main explosive is prepared from RDX, HMX, CL-20, TATB, NTO, NQ, LLM-105 or the mixture thereof, the combustion agent is prepared from aluminum powder, zinc powder, zirconium powder, modified aluminum powder, magnalium powder, boron-aluminum alloy powder, aluminum hydride and magnesium hydride, the oxidizing agent is prepared from ammonium perchlorate, ammonium nitrate and ammonium dinitramide, and thermite is adopted as the high-density high-energy additive. The prepared explosive mixture has the high energy density, the density is larger than or equal to 2.0 g / cm<3>, and the heat of explosion in unit volume is larger than or equal to 16000 J / g.

The invention discloses a surface modification and coating method for ammonium dinitramide, in order to solve a problem on moisture absorption in a process of using the ammonium dinitramide. The method comprises the following steps: adding ammonium dinitramide, a dispersion medium and a surface modification and coating agent in a reaction flask, heating until the ammonium dinitramide is completely melted, decreasing temperature and separating out solid particles, and filtering to obtain surface-modified and coated ammonium dinitramide particles. Under conditions that relative humidity is 50% and temperature is 35 DEG C, after modification and coating, a saturated moisture rate of the ammonium dinitramide is reduced by 85%, and thus a problem on moisture absorption of the ammonium dinitramide is effectively solved. According to the method disclosed by the invention, not only is moisture absorption of the ammonium dinitramide effectively improved, but also an ammonium dinitramide crystal can be pelletized.

The invention relates to a titanium oxide supported sub-nano rhodium catalyst and an application thereof. Specifically, the rhodium content is 0.5-5% of the total mass of the catalyst, and is highly dispersed on a titanium oxide carrier in a sub-nano (0.5-1 nm) form. The rhodium dispersed on the catalyst carrier in the sub-nano form is used as an active center of a catalytic reaction, can be used for oxidation elimination of trace carbon monoxide (CO) in an ultra-low temperature environment and low temperature catalytic decomposition of liquid unit ammonium dinitramide (ADN) aerospace propellants.

The invention relates to an epoxy-terminated polyether compound as well as a preparation method and application thereof and belongs to the field of solid propellants. The compound comprises two epoxy-terminated groups; the preparation method of the epoxy-terminated polyether compound comprises the following steps: taking polyether diol and metal sodium or sodium hydride to react to generate polyether diol sodium; continually taking the polyether diol sodium and epoxy chloropropane to react and removing sodium chloride, so as to synthesize epoxy-terminated polyether. The epoxy-terminated polyether compound keeps good structure and performance of a traditional adhesive and is not sensitive to impurities including water and the like; meanwhile, the epoxy-terminated polyether compound has chemical inertness on novel energy-containing materials including ADN (Ammonium Dinitramide), CL-20, AlH3 and the like and good compatibility; after the compound is solidified, a propellant medicine block has no air pores and relatively good mechanical properties. The preparation method of the epoxy-terminated polyether compound is simple and feasible; a catalyst is not needed and an intermediate does not need to be separated; the epoxy value of the product is easy to control and large-scale production is convenient to realize.

This invention relates to energetic compositions, which offer increased performance in conjunction with a total absence of halogen based oxidizers to eliminate exhaust products, such as hydrogen chloride. The oxidizers of choice are various combinations neat ammonium dinitramide, ammonium dinitramide prills and CL-20, because these oxidizers do not produce halogen containing exhaust products, such as the HCl gas of ammonium perchlorate. The exhaust these novel propellants consist mostly of CO2, H2O, N2, and small amounts of CO. These exhaust species are friendlier and much less hazardous to the environment than those emitted by conventional AP-based propellants. The plasticizers are selected from energetic plasticizers that do not contain halogens, but maintain other desirable properties.

The invention belongs to the field of energetic materials, and provides a method for maintaining the structure and morphology of an ADN (ammonium dinitramide) spherical particle. The method adopts an atomic layer deposition technology to cause two kinds of reaction precursors to alternately pass through a reaction chamber, and then the reaction precursors chemically react on the surface of the AND spherical particle to generate a cladding membrane. The cladding membrane completely covers the entire outer surface of the AND spherical particle, and the thickness can be precisely adjusted. When the thickness of the cladding membrane is controlled in the range of nanometer size, the content of cladding membrane is below 1 percent of the total mass of a system, and the influence on the energy characteristics of AND is small. In a moist environment, the cladding membrane plays a role of structural support in the AND spherical particle after absorbing moisture, so that the spherical particles cannot be dissolved or mutually fused. Through simple drying treatment, the AND spherical particle can remove water to restore the using state, and the structure and morphology and the physical and chemical properties of the AND spherical particle are not changed. The method is simple to operate, is low in cost, and facilitates industrial implementation and popularization.

The invention relates to an ADN / A1 / MxOy-based nano composite energetic material and a preparation method thereof, the method comprises the following steps: dissolving metal (M) salt in a solvent to prepare a solution with a certain mole concentration, weighing an oxidizing agent ammonium dinitramide (ADN) and adding in the above solution, stirring until the solution is in a transparent, respectively adding a fuel nano aluminium powder and a proton trapping agent, stirring for 10-20 minutes, standing and aging for several days, and performing supercritical drying by carbon dioxide, and obtaining the ADN / A1 / MxOy-based nano composite energetic aerogel. The preparation method has the advantages of strong operationality, controllable proportion of oxidizing agent to fuel and simple required equipment, the obtained product has the advantage of good safety performance, is suitable for amplification production, and provides thinking for development of the future energetic material, the ADN / A1 / MxOy-based nano composite energetic material can completely or partially replace the current dangerous and complex energetic material possibly, and is an important direction for development of the nano energetic materials such as solid propellant, and explosives and powders.

A substantially anhydrous solid or liquid chemical adduct formed by reacting hydrogen peroxide, and a compound selected from the group consisting of sodium nitrate, potassium nitrate, ammonium nitrate, ammonium dinitramide and mixtures thereof.

The invention discloses a method for preparing graphene-coated spheroidization ammonium dinitramide. The method includes steps of firstly, preparing spheroidization ammonium dinitramide by the aid ofnormal-temperature or low-temperature re-crystallization processes under joint induction effects of ultrasonic waves-nitramine explosive; secondly, preparing graphene-coated spheroidization ammonium dinitramide composite materials by the aid of ultrasonic-anti-solvent processes. The method has the advantages that conventional high-temperature melting ammonium dinitramide spheroidization technologies are improved, accordingly, risks due to local overheating or aggregation of materials at the high temperatures can be reduced, and the technological realization of spheroidization-coating processescan be expanded; the spheroidization ammonium dinitramide is coated by high-activity graphene oxide with mutual effects with the spheroidization ammonium dinitramide, accordingly, binding force between the graphene oxide and the spheroidization ammonium dinitramide can be increased, and the moisture absorption of ammonium dinitramide can be obviously deteriorated.

The invention discloses a method for preparing superhydrophobic spherical ADN (ammonium dinitramide) based on interfacial tension. The method comprises the following steps: step one, melting an ADN crystal and spraying the crystal onto a low surface energy material; step two, after the surface of the ADN crystal is coated with a layer of low surface energy material, performing cooling to solidifyand crystallize the ADN crystal to obtain superhydrophobic spherical ADN. Super-hydrophobic concept and spheroidization for reducing hygroscopicity of ADN are combined, the super-hydrophobic sphericalADN crystal is prepared with a solid-phase melting method, the particle size is adjustable, hygroscopicity of the superhydrophobic spherical ADN crystal is greatly reduced, no liquid solvent or non-solvent is used in the main process, the method is green and environmentally friendly, the process is simple, and the cost is low; especially, under the conditions that the temperature is 60 DEG C, therelative humidity is 80% and test time is 400 hours, the moisture absorption rate of superhydrophobic spherical AND is reduced by 55% as compared with ADN raw materials and is much higher than that of other reported ADN moisture absorption prevention methods. Therefore, a technical route is provided for wide application of ADN in solid propellants.

The invention discloses a method for constructing ammonium dinitramide coating layer by adopting graphene oxide Pickering emulsion, which solves the problem that ammonium dinitramide is easy to absorbmoisture. The solvent which cannot dissolving ammonium dinitramide is used as the dispersion medium, amphiphilic graphene oxide is used as stabilizer, so as to prepare a stable emulsion system of ammonium dinitramide droplets / dispersion medium by ultrasonic irradiation and homogenization at the melting temperature of ammonium dinitramide. Ammonium dinitramide composite powder coated with grapheneoxide was obtained by cooling the emulsion system rapidly and making ammonium dinitramide droplets cool and recrystallize. Then, graphene coated ammonium dinitramide is obtained by placing the composite powder in low temperature reduction steam. Compared with the traditional ammonium dinitramide coating method, the invention does not need additional assistant, and the experiment is simple and easy to operate. The morphology and thickness of the graphene coating prepared by Pickering emulsion method are precisely controllable, and the hygroscopicity of ammonium dinitramide is significantly reduced after coating.

The invention discloses an environment-friendly propellant, consisting of the following components in parts by weight: 20-60 parts of oxidant, 15-60 parts of nitrocellulose and 3-8 parts of adhesive, wherein the oxidant is selected from one of ammonium dinitramide and binitro azoxy bifurazan or a mixture of the two components in any proportion; the adhesive is selected from polyvinyl alcohol or strong adhesive powder. By adopting the formula, the smoke volume generated by combustion of the propellant can be greatly reduced, meanwhile, under the same working condition, compared with military nitrate, the use amount of the propellant can be reduced by 15-30%, and the emission height is equivalent.

The invention relates to an antistatic smokeless sulfur-free firecracker nitrate agent and a preparation method thereof, belonging to the field of environment-friendly pyrotechnic compositions. The firecracker nitrate agent comprises, desensitized hexogen, nitrified bamboo cellulose, modified ammonium dinitramide, magnesium stearate, 1,3-dimethyl-1,3-diphenyl urea, dicyandiamide, amino silicon oiland an antistatic agent. According to the invention, desensitized hexogen is used as a main component, and modified ammonium dinitramide is used as an oxidant, so an oxygen content is sufficient, andcombustion effect is ensured; the nitrified bamboo cellulose, 1,3-dimethyl-1,3-diphenyl urea, magnesium stearate and dicyandiamide are adopted, and the antistatic agent and amino silicone oil are added, so the mechanical properties, stability and antistatic capacity of the firecracker nitrate agent can be remarkably improved, and the safety and reliability of the firecracker nitrate agent in theprocesses of production, storage and use are guaranteed; meanwhile, the firecracker nitrate agent does not contain a sulfur element or any metal powder, so the preparation of the smokeless sulfur-freefirecracker nitrate agent can be truly realized.

The invention relates to the technical field of fireworks and firecrackers, in particular to a desensitizer for pyrotechnic composition and preparation method. According to the parts by weight, the desensitizer for pyrotechnic composition comprises 20-30 parts of magnesium oxide, 10-15 parts of zinc oxide, 2-4 parts of calcium stearate, 1-5 parts of antimony trioxide, and 10-15 parts of titanium dioxide, 5-10 parts of polyazide glycidyl ether, 1-3 parts of ammonium dinitramide. The desensitizer for pyrotechnic composition has good diffusion performance, moisture resistance, stability and invariability, which can be stored for a long time without deterioration and can better mix the other components of pyrotechnics.

The present invention provides a high energy solid propellant containing an oxidizer, binder and fuel, wherein the fuel and / or the propellant as a whole is encapsulated or microencapsulated so as prevent premature reaction while still maintaining the energetic properties thereof. The oxidizer is preferably ammonium perchlorate, ammonium nitrate or ammonium dinitramide. The binder is preferably polymeric hydrocarbons or polymers. The fuel is preferably lithium hexahydridoborane or lithium hexahydridoalane.

The present invention provides an ecofriendly method for preparing dinitramidic acid and its salts by nitration of ammonium sulfamate with fuming nitric acid as a nitrating agent using solid acid catalysts selected from the group consisting of a montmorillonite clay catalyst and metal ion exchanged K10 montmorillonite clay catalysts and surface supported catalysts and preparation of ammonium dinitramide by neutralization of the dinitramidic acid with ammonia and separation of ammonium dinitramide.

The invention relates to an alumina-supported platinum (Pt) catalyst and a preparation method and application thereof. The catalyst is specifically a composite catalyst with a single component Pt as an active center and inert alumina as a carrier, wherein the platinum accounts for 0.5 to 5% of the total mass of the catalyst, and is highly dispersed on the alumina in a form of clusters with a cluster size of 0.5 to 3.0 nm. The catalyst is used in oxidation elimination of carbon monoxide (CO) in an ultra-low temperature environment (-80 to 0 DEG C), and purification of a hydrogen source used ina proton exchange membrane fuel cell power generation system. In particular, the catalyst is also suitable for catalytic decomposition of ammonium dinitramide (ADN) at low temperature. The catalyst has characteristics of simple preparation method, high selectivity and high stability, and has good industrial application prospect.

The invention provides a preparation method of hydroxylamine dinitramide. The method comprises the following steps: an aqueous solution of ammonium dinitramide goes through a cation resin exchange column at a certain flow rate, and the obtained effluent is collected; and the collected effluent is dropwise added to a hydroxylamine solution at a normal temperature while stirring, and vacuum freeze-drying is carried out after the addition is completed in order to obtain the hydroxylamine dinitramide. The method has the advantages of environmental protection, harmlessness and high yield, and allows the purity of HADN to be higher than 99.5%, the content of nitrate radicals to be less than 0.1%, the content of metal ions to be less than 5 ppm and the content of sulfate radicals to be less than8 ppm.

The present invention relates to a reactor for the decomposition of ammonium dinitramide-based liquid monopropellants into hot, combustible gases for combustion in a combustion chamber, and a rocket engine or thruster comprising such reactor, which reactor further comprises an inner reactor housing accommodating a heat bed and a catalyst bed, and separating the heat bed and catalyst bed from contact with the inner surface of the reactor housing.

The present invention relates to a reactor for the decomposition of ammonium dinitramide-based liquid monopropellants into hot, combustible gases for combustion in a combustion chamber, and a rocket engine or thruster comprising such reactor, wherein the reactor comprises a heat bed exhibiting catalytic activity.

The invention belongs to the technical field of ammonium dinitramide purification and application, and in particular relates to a method for the separation and preparation of ammonium dinitramide, a novel high-energy oxidant. The method comprises the following effective steps: firstly, adding the reverse phase chromatography filler into the chromatographic column for use; using ammonium sulfamate as a raw material, the ADN crude product synthesized by the mixed acid method is prepared for use; the ADN-containing crude product synthesized by the mixed acid method Add water to constant volume, and pump it into the chromatographic column system according to the flow rate to load the sample; wash the ADN crude product chromatographic column with purified water after the sample is loaded; / water to elute the loaded ADN crude product chromatography column; the elution process is detected and analyzed by high-performance liquid chromatography (HPLC), and high-purity ADN fractions are collected; the collected high-purity ADN fractions are concentrated and then crystallized at low temperature , to obtain high-purity ADN products. The method of the invention is simple and has an operation scheme. It is safe, reliable and produces no pollutants, and is suitable for large-scale promotion and use.

The invention discloses a chlorine-free orange pyrotechnic agent based on an energetic metal organic framework, and relates to the technical field of energetic composite materials. The pyrotechnic agent comprises the following component, in percentages by mass: 20-60% of the energetic metal organic framework material [Cs(ABTNA)H2O]n, 8-16%of 10-mesh metal aluminum powder, 30-62% of ammonium dinitramide, and 2% of binder phenolic resin, wherein ABTNA in the [Cs(ABTNA)H2O]n is 3-amino-3'-nitramino-5,5'-bi-1,2,4-triazole. According to the pyrotechnic agent provided by the invention, the nitrogen-rich energetic metal organic framework material and ingredients such as the AND and the aluminum powder are mixed to prepare the pyrotechnic agent, and the prepared pyrotechnic agent has the characteristics of no moisture absorption and no chlorine, thereby solving the important practical application problems that an inorganic salt in a current formula easily absorbs moisture and the chlorine-containing formula pollutes the environment.

The invention relates to a deformable solid propellant which is prepared from the following raw materials: an oxidant, a reducing agent, a shape memory adhesive and a plasticizer, wherein the oxidantis ammonium perchlorate and ammonium dinitramide; the reducing agent is nano aluminum powder and magnesium powder; the plasticizer is acetyl triethyl citrate. The shape memory polymer is used as an adhesive of the solid propellant, and the propellant is endowed with the deformation capability to a certain extent while the performance of the adhesive is not influenced, so that the change of a the combustion surface shape is realized, the performance of an engine is changed, and the engine can better adapt to the flight environment.

The invention relates to a subnano rhodium catalyst supported by titanium oxide and its application. Specifically, the rhodium content is 0.5-5% of the total mass of the catalyst, and it is highly dispersed on the titanium oxide carrier in the form of sub-nanometer (0.5-1 nm). The subnano-dispersed rhodium on the catalyst carrier of the invention is used as the active center of the catalytic reaction, and can be used for the oxidation elimination of trace carbon monoxide (CO) in an ultra-low temperature environment and the low-temperature catalytic decomposition of liquid unit ammonium dinitramide (ADN) aerospace propellant.

The invention relates to a preparation method for a torispherical ammonium dinitramide (ADN) crystal. The method for preparing the torispherical ADN crystal is realized by testing different proportions and different temperatures of ADN and a solvent. The method is characterized by comprising the following steps: preparing an ADN solution at a certain temperature in a certain proportion, and addingnon-solvent dichloromethane so as to obtain the torispherical ADN crystal. The torispherical ADN crystal prepared by using the preparation method provided by the invention is free of addition of anyinert substances. The ADN crystal has a regular morphology and a torispherical crystal structure. Compared with a crystal obtained by using a method in the prior art, the torispherical ADN crystal prepared by using the preparation method provided by the invention is greatly reduced in impact sensitivity and has low hygroscopicity.

The invention discloses a quantitative analysis method for the content of ADN in an ammonium dinitramide (ADN, NH4N (NO2) 2) aqueous solution or solid. The method includes: detecting the content of sulfate radical (SO4 < 2->) and nitrate radical (NO3 <->) impurities in the ADN sample through an ion chromatography method; detecting the content of metal ions (K < + >, Na < + >, Ca < 2 + > and Mg < 2 + >) in the sample through an ICP method; detecting the content of total ammonium ions (NH4 +) in the sample by a formaldehyde-acid-base titration method; and calculating the content of dinitramide ions (N (NO2) 2-) in the sample according to the balance of anions and cations in the solution. If N (NO2) 2-anions correspond to NH4 + cations, calculating the content of ADN in the sample. The method effectively avoids the problem that no commercially available ADN standard sample is available for quantitative detection, initiates an analysis method capable of accurately quantifying the ADN component in the ADN sample without the ADN standard sample, and can effectively meet the quantitative detection requirement of the ADN content in the ADN product.