Showing papers on "Ammonium perchlorate published in 2020"

Ammonium perchlorate-based molecular perovskite energetic materials: preparation, characterization, and thermal catalysis performance with MoS2

Abstract: In this study, ammonium perchlorate (AP)-based molecular perovskite structural high-energetic materials (H2dabco)[NH4(ClO4)3] (DAP) were fabricated and their catalytic performance upon the addition...

Transition Metal Complexes Based on Hypergolic Anions for Catalysis of Ammonium Perchlorate Thermal Decomposition

Abstract: On the basis of hypergolic dicyandiamide (DCA) and cyanoborohydride (CBH) anions, 1-methyl-1,2,4-triazole (MTZ) ligand, and transition metal (Co/Ni/Cu) cations, five hypergolic coordination compoun...

Facile synthesis of RGO-Fe 2 O 3 nanocomposite: A novel catalyzing agent for composite propellants

Abstract: Whereas ferric oxide particles are common catalyst for energetic oxidizers such as ammonium perchlorate (APC), reduced graphene oxide (RGO) with superior thermal conductivity as well as high interfacial surface area could be candidate substrate for advanced catalytic systems. This study reports on the facile synthesis of RGO-Fe2O3 nanocomposite as a novel catalyzing agent for APC oxidizer. GO was developed via oxidation of graphite using Hummer’s method, while RGO was developed via GO reduction with hydrazine hydrate. RGO-Fe2O3 nanocomposite was developed via direct precipitation method. Morphological characterization of RGO-Fe2O3 nanocomposite demonstrated the formation of hematite RGO-Fe2O3 nanocomposite in the form of rod-shaped crystals with average crystallite size 30 nm. The synthesized RGO-Fe2O3 nanocomposite was effectively-encapsulated into APC particles via co-precipitation technique. The catalytic performance of RGO-Fe2O3 nanocomposite on APC thermal behavior was evaluated using DSC and TGA. RGO-Fe2O3 nanocomposite demonstrated superior catalytic performance; APC initial endothermic decomposition was decreased by 16% which could be ascribed to enhance the thermal conductivity and catalytic efficiency of the developed hybrid. APC total heat release was enhanced by 83%; this could be ascribed to superior interfacial surface area. Gaseous products could be efficiently-adsorbed on the catalyst surface offering high combustion enthalpy.

Catalytic Effect of Added Fe2O3 Amount on Thermal Decomposition Behaviors and Burning Characteristics of Ammonium Nitrate/Ammonium Perchlorate Propellants

Abstract: Ammonium nitrate (AN) and ammonium perchlorate (AP) are investigated as propellants for their thermal decomposition behaviors and burning characteristics. The performance effects of AP particle siz...

Synergistic catalysis of ZIF-67@CNTOH in thermal decomposition of ammonium perchlorate

Abstract: A composite material of ZIF-67 and hydroxylated carbon nanotube (CNTOH) was prepared by a simple method and applied to catalytic decomposition of ammonium perchlorate (AP). The AP-based composites with ZIF@CNTOH added were tested by thermal analysis methods including differential scanning calorimetry (DSC) and thermogravimetric (TG). The results showed that the low temperature decomposition peak of the samples was weakened and even disappeared after the addition of the catalyst, and the high temperature decomposition peak was significantly advanced. When the content of CNTOH in ZIF@CNTOH is 5% and ZIF@CNTOH accounts for 5% in AP composite, the pyrolysis peak temperature was reduced from the original 409.7 °C to 298.8 °C, proved the significantly catalytic effect. This is mainly due to the effective uniform loading of transition metal ions on ZIF and the excellent electrical and thermal conductivity of CNTOH. The combination of them makes it achieve the best synergistic catalytic effect.

Ferric Oxide Colloid: A Novel Nano-catalyst for Solid Propellants

Abstract: Even though ammonium perchlorate (AP) is universal oxidizer; its initial decomposition is an endothermic process. This feature could render high burning rate regime. Ferric oxide particles are candidate catalyst for AP decomposition. This study reports on sustainable fabrication of colloidal ferric oxide particles. Ferric oxide particles demonstrated stable colloidal suspension with zeta value of 38.5 mV. TEM micrographs revealed mono-dispersed particles of 3 nm average particle size. XRD diffractogram demonstrated highly crystalline structure. Ferric oxide nanoparticles were coated with AP particles via co-precipitation technique. The efficiency of ferric oxide particles as nano-catalyst for AP was evaluated using DSC and TGA. Ferric oxide particles reduced AP initial endothermic decomposition by 40%. The following two exothermic decomposition peaks were combined together into one single peak with an increase in total heat release by 47.5%. These novel catalytic features can extend applications of ferric oxide particles in catalyzed combustion reactions.

Aloe vera leaf extract-assisted facile green synthesis of amorphous Fe 2 O 3 for catalytic thermal decomposition of ammonium perchlorate

Abstract: Fe2O3 is a well-known catalyst for thermal decomposition of ammonium perchlorate (AP). Amorphous Fe2O3 nanoflakes were biosynthesised by a novel sol–gel method using Aloe vera leaf extract, and its catalytic effect on thermal decomposition of AP was investigated. The precursor ferric nitrate–Aloe vera gel was calcined at three different temperatures. The oxides were characterised by Fourier-transform infrared spectroscopy, X-ray powder diffraction, atomic force microscopy, field emission scanning electron microscopy and transmission electron microscopy. Microscopy analyses revealed that Fe2O3-250 consists of a porous structure as aggregates of many nanoflakes of ~ 2 nm diameter. The catalytic activity of the synthesised products on thermal decomposition of AP was evaluated using thermogravimetry–differential scanning calorimetry. The presence of 2.0% of mesoporous Fe2O3-250 catalyst (surface area of 208 m2 g−1) enhanced the rate of high-temperature decomposition of AP by decreasing the peak decomposition temperature from 367 to 337 °C. Average activation energy of thermal decomposition of AP was calculated using Flynn–Wall–Ozawa method reduced from 145 to 128 kJ mol−1 in the presence of the catalyst. The high surface area of mesoporous Fe2O3-250 originated from its amorphous nature makes it a potential catalyst for thermal decomposition of AP.

Investigating the effect of chemical ingredient modifications on the slow cook-off violence of ammonium perchlorate solid propellants on the laboratory scale

Abstract: Rocket propellants that contain ammonium perchlorate (AP) often have a violent response during slow heating. Two laboratory tests have been developed to determine the reaction violence of these mat...

A graphene oxide functionalized energetic coordination polymer possesses good thermostability, heat release and combustion catalytic performance for ammonium perchlorate

Abstract: A new energetic coordination polymer (ECP) composite, namely GO-Cu(ii)-AmTZ, has been synthesized by 3-amino-1,2,4-triazole (AmTZ) and multifunctional graphene oxide (GO) coordination with Cu(ii) successively. The ECP composite was further characterized through SEM, EDS and XPS analysis as well as FTIR and Raman spectroscopy. It shows high thermostability, high decomposition heat release and insensitivity to mechanical stimuli. What's more, thermal analysis data for ammonium perchlorate (AP) have been obtained by mechanically mixing GO-Cu(ii)-AmTZ and AP. The low-temperature decomposition (LTD, 335.3 °C) and high-temperature decomposition (HTD, 441.3 °C) peaks of AP were reduced to an exothermic peak at 298.4 °C at a heating rate of 10 °C min-1. GO-Cu(ii)-AmTZ exhibits outstanding catalytic performance by decreasing the activation energy from 168.7 kJ mol-1 to 122.4 kJ mol-1, indicating its promising application as a combustion catalyst for improving the thermal-catalytic decomposition performance of energetic materials largely. In addition, thermal analysis techniques including thermogravimetry coupled with mass spectrometry (TG/MS) and thermogravimetry coupled with infrared spectrometry (TG/IR) were employed to determine the decomposition mechanisms.

Nanohybrids of reduced graphene oxide and cobalt hydroxide (Co(OH)2|rGO) for the thermal decomposition of ammonium perchlorate

Abstract: The catalytic activity of nanoparticles of cobalt hydroxide supported on reduced graphene oxide, Co(OH)2|rGO, was studied for the decomposition of ammonium perchlorate (AP), the principal ingredient of composite solid propellants Co(OH)2|rGO was synthesized by an in situ reduction method, which avoided the application of extremely high temperatures and harsh processes rGO stabilized the nanoparticles effectively and prevented their agglomeration The performance of Co(OH)2|rGO as a catalyst was measured by differential scanning calorimetry Co(OH)2|rGO affected the high-temperature decomposition (HTD) of AP positively, decreasing the decomposition temperature of AP to 292 °C, and increasing the energy release to 290 J g−1 The diminution of the HTD of AP by Co(OH)2|rGO is in between the best values reported to date, suggesting its potential application as a catalyst for AP decomposition

Functionalization graphene oxide with energetic groups as a new family of metal-free and energetic burning rate catalysts and desensitizers for ammonium perchlorate

Abstract: A new family of metal-free and energetic graphene oxide (GO)-based burning rate catalysts (FGO 1–6) with excellent catalytic and desensitization performances for ammonium perchlorate (AP) were synthesized by nucleophilic substitution reaction of energetic functional groups with acylated GO. The chemical structures, thermal stabilities, catalytic properties and desensitization performances of the functionalized GO were determined. It was shown that the functional groups on the nanosheets of GO imparted its energetic performance and thermal stability, and the catalytic properties and desensitization performances were also enhanced. The reduced mass loss rate along with enhanced residues formation indicated significant improvement in thermal stabilities for FGO 1–6 compared with GO. Besides, not only did FGO 1–6 lower the decomposition temperature, but also enhanced the overall heat for the thermal decomposition of AP. The FGO 1–6 decreased the exothermic peak of the high-temperature decomposition process of AP by 88.1, 93.4, 98.3, 85.8, 90.7 and 79.8 °C, corresponding to the decomposition heat of AP increased significantly from 655 to 2707, 2915, 3529, 3002, 3642 and 2718 J g−1, which exhibited better catalytic activity than that of GO. In addition, the mechanical sensitivities of AP/GO and AP/FGO 1–6 mixtures decreased obviously in comparison with pure AP were also obtained. A new family of metal-free and energetic GO-based burning rate catalysts with excellent catalytic properties and desensitization performances for ammonium perchlorate were developed.

Evaluation of the Performance of Some Metals and Nonmetals in Solid Propellants for Rocket-Ramjet Engines

Abstract: A comparative evaluation of the use of various metals and nonmetals as fuel components of a solid propellant containing ammonium perchlorate as an oxidizer and rubber as a binder was performed using the flight range criterion of a rocket-ramjet aircraft taking into account the expected completeness of combustion of individual components. The influence of the energetic properties of the propellant on the technical and economic characteristics and flight performance of the aircraft was also taken into account. The aircraft flight range was calculated by numerical integration of flight dynamics equations. Based on the results, it is recommended that a number of fuel components should be studied in more detail, in particular, for the purpose of the full or partial replacement of boron currently used in solid propellants for rocket-ramjet engines.