Catalytic Decomposition Of Ammonium Perchlorate Research Articles

Oriented Assembled Prussian Blue Analogue Framework for Confined Catalytic Decomposition of Ammonium Perchlorate.

The design of highly dispersed active sites of hollow materials and unique contact behavior with the components to be catalyzed provide infinite possibilities for exploring the limits of catalyst capacity. In this study, the synthesis strategy of highly open 3-dimensional frame structure Prussian blue analogues (CoFe-PBA)wasexplored through structure self-transformation, whichwasjointly guided by template mediated epitaxial growth, restricted assembly and directional assembly. Additionally, good application prospect of CoFe-PBA as combustion catalystwasdiscussed. The results show that unexpected thermal decomposition behavior can be achieved by limiting AP(ammonium perchlorate) to the framework of CoFe-PBA. The high temperature decomposition stage of AP can be advanced to 283.6 °C and the weight loss rate can reach 390.03% min-1 . In-situ monitoring shows that CoFe-PBA can accelerate the formation of NO and NO2 . The calculation of reaction kinetics proved that catalytic processwasrealized by increasing the nucleation factor. On this basis, the catalytic mechanism of CoFe-PBA on the thermal decomposition of APwasdiscussed, and the possible interaction process between AP and CoFe-PBA during heatingwasproposed. At the same time, another interesting functional behavior to prevent AP from cakingwasdiscussed.

A strategy for modulating the catalytic active center of AP thermal decomposition and its application: La-doped MgCo2O4

La diffuses into the main lattice of MgCo2O4 (Lax-MgCo2O4), exposing more Co3+ active centers: (1) La3+, O2−, high Co3+ concentration, high conductivity promote AP decomposition. (2) The highly active Lax-MgCo2O4 becomes potential catalyst for CSPs.

Facile preparation of CoFe-based oxide nanosheets derived from CoFe-layered double hydroxide for the thermal catalytic decomposition of ammonium perchlorate

In this work, CoFe-based oxide nanosheets were prepared by a facile method and its catalysis effects on the thermal decomposition of ammonium perchlorate (AP) were studied. CoFe-based oxide nanosheets were obtained from hydrothermal process and high-temperature treatment of CoFe-layered double hydroxide. The samples were characterized by scanning electron microscopy and high-resolution transmission electron microscopy. The thermal catalytic decomposition of AP with CoFe-based oxide nanosheets as catalysts was investigated by differential scanning calorimetry and coupling Fourier transform infrared spectrometer. The results showed that the CoFe-based oxide samples with the width size of 200–300 nm and the thickness size of ∼10 nm show the inherent catalytic ability. With 10 wt% of CoFe-based oxide nanosheets added, the decomposition temperature of AP was reduced by 127.5 °C from 431.0 °C to 303.5 °C. The apparent activation energy was decreased by 61.1 kJ/mol from 177.3 kJ/mol of raw AP to 116.2 kJ/mol of AP with 10 wt% of CoFe-based oxide nanosheets added. The thermal catalysis decomposition mechanism of AP with CoFe-based oxide nanosheet material promoting was proposed. This work offered a novel idea toward preparation and application of functional material layered double hydroxide in the field of energetic materials.

New Insights into the Catalytic Decomposition of Ammonium Perchlorate and Decomposition Mechanism by Nano‐CuO Dispersed in Graphite‐Carbon Nitride Nanosheet Composites

AbstractEnhancing the exothermic decomposition of ammonium perchlorate (AP) is of great significance to obtain solid propellants with excellent combustion performance. Herein, we prepared a series of composites for catalyzing the exothermic decomposition of AP by a facile method with different masses of nano copper oxide (n‐CuO) dispersed in graphene‐nitride carbon (g‐C3N4) nanosheets. Among them, n‐CuO‐8/g‐C3N4showed the best catalytic activity, which reduced the high‐temperature decomposition (HTD) value by 95.0 °C, and increased the total heat release by 505 J ⋅ g−1. The n‐CuO‐12/g‐C3N4also reduced the activation energy (Ea) of the HTD stage by 47.34 kJ ⋅ mol−1. The catalytic mechanism study suggested that the n‐CuO‐X/g‐C3N4composites promoted the transition of electrons (e−) and holes (h+) from ClO4−to NH4+and inhibited the recombination of e−and h+, which further enhanced the exothermic decomposition of AP. During decomposition, the transformation of N2O to NO was significantly inhibited by the n‐CuO‐X/g‐C3N4composites, thus increasing the integral heat release as evidenced by Real‐time thermogravimetry/Fourier transform infrared spectroscopy. This study illustrated that n‐CuO‐X/g‐C3N4composites are catalysts for the efficient decomposition of AP, which further enhance the energy performance of solid propellants.

The catalytic decomposition and kinetic analysis of ammonium perchlorate on MgO nanoflakes

The catalytic decomposition of ammonium perchlorate (AP) by magnesium oxide (MgO) nanoflakes (NFs) with hexagonal and quasi-circular structures was investigated. MgO NFs were synthesized by hydrothermal process and characterized by TEM, FESEM, XRD and BET. Catalytic activities of MgO NFs were researched via TG-DSC analysis. After MgO NFs were added to AP, the temperature of AP decomposition rose in the first exothermic stage and reduced in the second exothermic stage. The catalytic performances of MgO NFs depended on the mass fraction in AP. MgO NFs with 2% (wt%) addition exhibited the highest catalytic efficiency. The kinetics of AP decomposition was studied by using Kissinger plot method. The results showed that MgO NFs had obvious influences on the kinetic parameters in the different stages of AP thermal decomposition.

A new oxygen-rich and poly-nitrogen energetic complex: synthesis, properties of high energy materials and catalytic decomposition of ammonium perchlorate

Preparing green materials with excellent performance based on coordination chemistry is a challenge. In the present work, a new energetic complex, [Co(Hatzc)2(H2O)2] · 2H2O (1) (H2atzc = 3-carboxyl-5-amino-1,2,4-triazole), was synthesized by the diffusion method and characterized by X-ray single-crystal diffraction, elemental analysis, infrared spectral analysis, and thermogravimetric analysis. The structural analyses illustrate that 1 exhibits a 0-D motif, linked by hydrogen-bonding interactions to give a 3-D supramolecular architecture. 1 shows good thermal stability (T dec =283 °C), low sensitivity (IS > 40J, FS > 360N), prominent detonation velocity (10.18 km s−1), and detonation pressure (44.99 Gp). The heat of detonation of 1 (4.109 kcal g−1) is higher than most classical energetic complexes as shown by density functional theory (DFT). In addition, 1 shows good catalytic activity toward AP (ammonium perchlorate) decomposition by thermodynamics and dynamic analysis, which indicates 1 is a potential energetic candidate in the solid propellant field.

Facet effect of Co3O4 nanocatalysts on the catalytic decomposition of ammonium perchlorate

Crystal facets can affect the catalytic decomposition of ammonium perchlorate, but the underlying mechanisms have long remained unclear. Here, we use the nanorods, nanosheets and nanocubes of Co3O4 catalysts exposing {110}, {111} and {100} facets as model systems to investigate facet effects on catalytic AP decomposition. The peak temperature of high temperature decomposition (HTD) process (THTD) of AP by nanorods, nanosheets and nanocubes Co3O4 decrease from 437.0 °C to 289.4 °C, 299.9 °C and 326.3 °C, respectively, showing obvious facet effects. We design experiments about AP decomposition under different atmospheres to investigate its mechanism and verify that the accumulation of ammonia (NH3) on AP surface can inhibit its decomposition and that the facet effects are related to the adsorption and oxidation of NH3. The binding energies of NH3 on the {110}, {111} and {100} planes calculated via density functional theory (DFT) are -1.774 eV, -1.638 eV, and -1.354 eV, respectively, indicating that the {110} planes are more favorable for the adsorption of NH3. Moreover, the {110} planes are readily to form CoNO structure, which benefits the further oxidation of the NH3.

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

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.

Catalytic decomposition of ammonium perchlorate on hollow mesoporous CuO microspheres

Hollow mesoporous CuO microspheres (CuO-HM) have been prepared by a hard-template method and their structure properties as well as catalytic performance in ammonium perchlorate (AP) decomposition were fully investigated by XRD, SEM, XPS, TG/DSC and TG/F-TIR methods. The results indicated that CuO-HM could be described as CuO micro-sized spheres composed of self-assembled nanoparticles, possessing hollow and mesoporous structure. Compared with CuO nanoparticles and CuO microspheres, CuO-HM has significantly improved catalytic efficiency in AP decomposition due to large surface area, easily accessible porous and hollow structure. Typically, CuO-HM could decrease the AP decomposition temperature by 105.7 °C and enhance the heat production by 735 J/g. TG/FT-IR results indicated that CuO-HM accelerated the thermal decomposition of AP mainly at the high temperature decomposition stage with the releasing of N2O, NO, NH3, H2O, HCl, O2 et al. This study demonstrated that hollow and mesoporous CuO was a promising catalyst for the application in solid fuel rockets propellants.

Trisodium citrate assisted synthesis of flowerlike hierarchical Co3O4 nanostructures with enhanced catalytic properties

Flowerlike hierarchical Co3O4 nanostructures were prepared by wet-chemical method with the assistance of trisodium citrate (Na3Cit·2H2O) under mild conditions. The phase, structure, morphology and properties of the Co3O4 nanostructures were characterized by X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) and UV–visible spectrophotometer. Substitution-oxidation ([Co2(CitH−1)2]4−→Co(OH)2→Co3O4) process was proposed for the possible evolution mechanism based on the results. Appropriate Na3Cit played an important role for the formation of flowerlike Co(OH)2 intermediates and Co3O4 nanostructures. The obtained flowerlike hierarchical Co3O4 nanostructures exhibited remarkable enhanced visible-light photocatalytic degradations of rhodamine B (RhB) and catalytic decomposition of ammonium perchlorate (AP).

Controllable Synthesis and Catalytic Property of Novel Copper Oxides (CuO and Cu<sub>2</sub>O) Nanostructures

Copper oxides (CuO and Cu2O) semiconductor micro- and nanostructures have been selectively synthesized using cupric nitrate trihydrate (Cu(NO3)2•3H2O), potassium biphthalate (KHC8H4O4) and sodium hydroxide (NaOH) as starting materials in water solution by a simple hydrothermal method. The phase and morphology of the products could be controlled by changing the amount of sodium hydroxide and sodium potassium biphthalate. X-ray diffraction (XRD), field scanning electron microscopy (SEM) and Raman spectra (Raman) were used to characterize the products. It was found that oval-shaped CuO, CuO nanoplates and octahedral Cu2O were prepared by adjusting the molar of the NaOH and KH C8H4O4, meaning that NaOH and KH C8H4O4 played an important role in the morphology and phase of the samples. The catalytic application in accelerating catalytic decomposition of ammonium perchlorate (AP) of the as-prepared samples was also investigated by means of differential scanning calorimetry (DSC). Compared with CuO (oval-shaped or plates), octahedral Cu2O exhibited better catalysis on thermal decomposition of AP. The present work can afford some guidance for the rationally controllable synthesis of other catalytic materials.

Solution inheritance of CoC 2 O 4 ·2H 2 O rods to nanoparticle-assembled Co 3 O 4 rods

Abstract An inheritance strategy for fabricating nanoparticle-assembled Co 3 O 4 rods was reported with CoC 2 O 4 ·2H 2 O rods as self-template in aqueous solution. The substitution–oxidation process (CoC 2 O 4 ·2H 2 O → Co(OH) 2 → Co 3 O 4 ) was investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT–IR). The amount of NaOH, crystal characters of Co(OH) 2 intermediates and growth time of Co 3 O 4 play important roles on the formation of the nanoparticle-assembled Co 3 O 4 rods. Trace residual CoC 2 O 4 ·2H 2 O is necessary for keeping Co 3 O 4 nanoparticles in rod-shaped assembly. Comparing with the Co 3 O 4 rods obtained by calcining CoC 2 O 4 ·2H 2 O rods at high temperature, the solution synthesized nanoparticle-assembled Co 3 O 4 rods performed higher activities on photocatalytic degradation of rhodamine B (RhB) and catalytic decomposition of ammonium perchlorate (AP).

Ferrocene-based sulfonyl dihydropyrazole derivatives: Synthesis, structure, electrochemistry and effect on thermal decomposition of NH4ClO4

Three ferrocene-based sulfonyl-substituted dihydropyrazoles 3a–c have been synthesized, from the corresponding α,β-unsaturated diketones, and fully characterized. The crystal structures of 3a–c have been confirmed by X-ray crystallography, and electrochemistry behaviors of 3a–c have been examined by cyclic voltammetry (CV). Representatively, the mechanism of the electron transfer in redox process of 3a has been verified by density functional theory (DFT) calculation. It has been found that the activity of catalytic decomposition of ammonium perchlorate (AP) is significantly lowered (by 62.9–104.7°C) with an addition of 3a–c. We expect that the ferrocene-based sulfonyl dihydropyrazole derivatives would have a great value in burning rate catalyst as composite solid propellants.

The atomic origin of high catalytic activity of ZnO nanotetrapods for decomposition of ammonium perchlorate

Distinct from the common well faceted ZnO nanorods (R-ZnO), ZnO nanotetrapods (T-ZnO) exhibited a remarkable catalytic activity for the thermal decomposition of ammonium perchlorate (AP): the activation energy at high temperature decomposition (HTD) was significantly decreased to 111.9 kJ mol−1, much lower than 162.5 kJ mol−1 for pure AP and 156.9 kJ mol−1 for AP with R-ZnO. This was attributed to more abundant atomic steps on the surface of T-ZnO than that of R-ZnO, as evidenced by HRTEM and density function theory (DFT) calculations. It was shown that the initiation step of perchloric acid (PA) decomposition happened much faster on stepped T-ZnO edges, resulting in the formation of active oxygen atoms from HClO4. The formed oxygen atoms would subsequently react with NH3 to produce HNO, N2O and NO species, thus leading to an obvious decrease in the activation energy of AP decomposition. The proposed catalytic mechanism was further corroborated by the TG-IR spectroscopy results. Our work can provide atomic insights into the catalytic decomposition of AP on ZnO nanostructures.

Controlled synthesis of Co3O4 single-crystalline nanofilms enclosed by (111) facets and their exceptional activity for the catalytic decomposition of ammonium perchlorate

Single-crystalline, thermally stable Co3O4 (111) nanofilms have been successfully synthesized without any surfactant.

ZnO Twin-Cones: Synthesis, Photoluminescence, and Catalytic Decomposition of Ammonium Perchlorate

ZnO twin-cones, a new member to the ZnO family, were prepared directly by a solvothermal method using a mixed solution of zinc nitrate and ethanol. The reaction and growth mechanisms of ZnO twin-cones were investigated by X-ray diffraction, UV-visible spectra, infrared and ion trap mass spectra, and transmission electron microscopy. All as-prepared ZnO cones consisted of tiny single crystals with lengths of several micrometers. With prolonging of the reaction time from 1.5 h to 7 days, the twin-cone shape did not change at all, while the lattice parameters increased slightly and the emission peak of photoluminescence shifted from the green region to the near orange region. ZnO twin-cones are also explored as an additive to promote the thermal decomposition of ammonium perchlorate. The variations of photoluminescence spectra and catalytic roles in ammonium perchlorate decomposition were discussed in terms of the defect structure of ZnO twin-cones.

CuO nanocrystals in thermal decomposition of ammonium perchlorate

CuO nanocrystals of different surface areas were prepared. All samples were characterized by X-ray diffraction, transition electron microscope, thermogravimetry, Brunauer-Emmett-Teller technique, Fourier transform infrared spectroscopy, and Raman spectroscopy. CuO nanocrystals showed a stable monoclinic structure. With increasing surface areas, the surface hydration became significant, which is followed by shifts in infrared frequencies and Raman phonon modes. CuO nanocrystals were explored as an additive to catalytic decomposition of ammonium perchlorate (AP). AP decomposition underwent a two-stage process. Addition of CuO nanocrystals led to a downshift of high-temperature stage towards lower temperatures.

Catalytic decomposition of ammonium perchlorate a survey

Abstract This paper reviews the role of additives in the combustion process of ammonium perchlorate. These additives are found to influence the low temperature decomposition of AP, its ignition temperature and burning rate. Transition metal oxides and various other compounds like chromates, halides, carbonates and perchlorates are well known decomposition catalysts. Admixture of these compounds is found to change the pattern and products of decomposition. The mechanism of decomposition is explained on activation energy obtained from thermal data. The activation energy of ammonium perchlorate is attributed to transfer of electron from perchlorate ion to ammonium ion and the role of catalyst is to accelerate this proccess. A complex is formed with metal ion C104 − and NH4 + radical which stabilizes the electron transfer process.

The catalytic effect of rare earth oxides on the thermal decomposition of ammonium perchlorate

The kinetics of the decomposition of ammonium perchlorate (AP) in the presence of rare earth oxides, yttrium oxide (Y2O3) and lanthanum oxide (La2O3) as catalysts have been investigated. The Prout-Tompkins and contracting-cube equations have been found to fit the isothermal thermogravimetry data of catalysed AP decomposition. Gases evolved during catalytic decomposition of AP were analysed by infrared spectroscopy by matrix isolation technique. The mechanism of the catalysed thermal decomposition of AP has also been discussed in terms of an electron transfer process.

Ammonium perchlorate decomposition in the presence of metallic oxides

Ammonium perchlorate decomposition in the presence of several oxides (Cr 2O 3, Fe 2O 3, CoO and Co 3O 4) was studied by differential scanning calorimetry. A general kinetic law was used in interpreting the experimental runs. It was observed that, in the catalytic decomposition of ammonium perchlorate, several reactions occur and contribute to the definition of the overall kinetic law. The relative contribution of these reactions and the actual kinetic parameters are evaluated.