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1.
Thermal decomposition of ammonium perchlorate   总被引:10,自引:0,他引:10  
This review represents an attempt to summarize literature data on thermal decomposition of ammonium perchlorate. The mechanism of thermal decomposition and various factors which influence on the thermal decomposition of ammonium perchlorate are discussed.  相似文献   

2.
A novel nanocomposite catalyst for thermal degradation of the ammonium perchlorate (AP) has been synthesized, and its effect on the thermal behavior of AP has been investigated. Preparation of the catalyst was carried out via functionalization of the graphene oxide with phenyl isocyanate and its noncovalent bonding to catocene. The catalytic activity of the catalyst was studied by thermal gravimetric analysis/differential scanning calorimetry at various heating rates. In addition, the effect of the catalyst on the AP thermal decomposition has been investigated by Kissinger and Friedman methods as two model-free methods for calculation of the activation energy parameter. According to the Kissinger method calculations, the Ea of AP decomposition reduced about 151 kJ⋅mol−1 lower than the reported value for pure AP in the presence of the catalyst. Calculation of the Ea value for various reaction conversion rates by the Friedman method also confirmed the Kissinger method results.  相似文献   

3.
In this review, an attempt to collect summarized literature data on catalytic effect of nanosized metals and nanoalloys on the thermal decomposition of ammonium perchlorates (AP) is made. Several experimental results show nanometals are more effective catalysts as compared to nanosized metal oxides. During decomposition process; metal react with oxygen containing species that are produced in decomposition process; and metal oxide is formed with large amount of heat which enhances the catalytic activity of metals as compared to metal oxide nanoparticles.  相似文献   

4.
CuO shuttle-like and flower-like nanocrystals were synthesized through a one-step, low-temperature solution-phase method in the presence of a cation surfactant, hexadecyl trimethyl ammonium bromide. These nanocrystals were studied as an additive for promoting the thermal decomposition of ammonium perchlorate (AP). With the addition of CuO shuttle-like and flower-like nanocrystals, the thermal decomposition temperature of AP decreased. The structure, particle size, and morphology of resulting CuO powders were characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. Thermogravimetric analysis technique was applied to investigate the thermal decomposition of mixtures of AP and as-prepared CuO nanocrystals.  相似文献   

5.
In the present paper a pure phase of the copper chromite spinel nanoparticles (CuCr2O4 SNPs) were synthesized via the sol–gel route using citric acid as a complexing agent. Then, the CuCr2O4 SNPs has been characterized by field emission scanning electron microscope (FE-SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). In the next step, with the addition of Cu–Cr–O nanoparticles (NPs), the effects of different parameters such as Cu–Cr–O particle size and the Cu/Cr molar ratios on the thermal behavior of Cu–Cr–O NPs + AP (ammonium perchlorate) mixtures were investigated. As such, the catalytic effect of the Cu–Cr–O NPs for thermal decomposition of AP was evaluated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). TGA/DSC results showed that the samples with different morphologies exhibited different catalytic activity in different stages of thermal decomposition of AP. Also, in the presence of Cu–Cr–O nanocatalysts, all of the exothermic peaks of AP shifted to a lower temperature, indicating the thermal decomposition of AP was enhanced. Moreover, the heat released (ΔH) in the presence of Cu–Cr–O nanocatalysts was increased to 1490 J g−1.  相似文献   

6.
The decomposition of basic copper carbonate in the presence and absence of NaNO3–KNO3 eutectic melt has been studied by employing isothermal TG and dynamic TG/DSC techniques. The rate constants for the decomposition in the presence of eutectic melt were found to be higher than when carbonate was heated alone. In both the cases copper oxide was found to be the end product. Catalytic activity of copper oxide obtained by the two methods were tested for the decomposition of ammonium perchlorate.  相似文献   

7.
To meet the requirement of generating more apparent specific heat release at lower temperatures for ammonium perchlorate (AP)-based composite solid propellants, the development of high-performance catalysts for improving the thermal decomposition properties of AP still remains essential and challenging. Herein, a novel catalyst, multichanneled hierarchical porous nanocomposite of CuO and carbonized butterfly wing (CuO/CBW), has been prepared through an in-situ reaction on original butterfly wing scales. Owing to the high active surface area and the good electrical and thermal conductivity, as well as the synergistic effect of CuO nanoparticles (20–25 nm) and CBW, CuO/CBW nanocomposite exhibits excellent catalytic activity for AP thermal decomposition in reducing the high-temperature decomposition temperature by 88.3°C, lowering the apparent activation energy from 190.0 to 103.1 kJ mol−1 and increasing the heat release from 255 to 1841 J g−1.  相似文献   

8.
Dihydropyrazole‐bridged dinuclear ferrocenyl derivatives (3a–3c) have been synthesized by the reaction of 1,3‐diferrocenyl‐2‐propen‐1‐on (1) with hydrazine, then acylation with acyl chloride directly. The structures were determined by mass spectrometry, IR and 1H NMR spectroscopy. The compound 3c was characterized by single‐crystal X‐ray analyses. It was found that compounds 3a–3c have significant catalytic effect on the decomposition of ammonium perchlorate (AP). Compared with the thermal decomposition of pure AP, adding 3a, 3b and 3c in AP decreases its decomposition temperature by 78.8, 74.3 and 57.1 °C, respectively. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

9.
Thermal decomposition of ammonium perchlorate based mixture with fullerenes   总被引:1,自引:0,他引:1  
The effects of fullerenes, including fellerene soot (FS), extracted fullerene soot (EFS) and pure C60 on the thermal decomposition of ammonium perchlorate (AP) compared with traditional carbon black (CB) catalyst has been studied by employing thermogravimetry (TG), differential thermal analysis (DTA), infrared spectroscopy (IR) and ignition temperature experiments. The results showed that the addition of CB and FS to AP reduced the activation energy as well as the temperature at maximum decomposition rate, but that of EFS and pure C60 had little effect on the thermal decomposition of AP, and among all catalysts, FS was the best one.  相似文献   

10.
An energetic coordination compound, Cu(HATZ)(PDA)(H2O) (HATZ?=?5-aminotetrazole, H2PDA?=?pyridine-2,6-dicarboxylic acid), has been synthesized and structurally characterized by single crystal X-ray diffraction. Copper(II) was coordinated by two oxygen atoms and nitrogen from PDA, one ring nitrogen of ATZ and one water to form a five-coordinate, distorted square-pyramidal structure. 3-D supramolecular architecture was formed by hydrogen bonding. Thermal decomposition of the compound was examined by DSC and TG-DTG analyses. The kinetic parameters of the first exothermic process of the compound were studied by Kissinger's and Ozawa–Doyle's methods. Sensitivity tests revealed that the compound was insensitive to mechanical stimuli. In addition, the compound was explored as additive to promote thermal decomposition of ammonium perchlorate by differential scanning calorimetry.  相似文献   

11.
In the present work, CuO nanoparticles grown on three‐dimensional nitrogen‐doped graphene‐based frameworks (CuO@3D‐(N)GFs) were synthesized using a two‐step method. After the synthesis of three‐dimensional nitrogen‐doped graphene, CuO nanoparticles were deposited on it, by adding cupric acetate followed by thermal treatment. Different analysis methods were used to characterize the products. The as‐prepared nanocomposite was used as a promising catalyst for thermal decomposition of ammonium perchlorate (AP) as one of the most common oxidizer in composite propellants. Differential scanning calorimetry (DSC) and thermogravimetry analysis (TGA) techniques were used to investigate the thermal decomposition of ammonium perchlorate. According to the DSC/TGA, high temperature decomposition of AP decreased to 111 °C in the presence of 4% CuO@3D‐(N)GFs and the total heat release (ΔH) from decomposition of AP increased to 1893 J g?1 which is much more than 590 J g?1 for pure AP.  相似文献   

12.
13.
Transition Metal Chemistry - Composite particles of carbon nanotubes (CNTs) and titanium dioxide (TiO2) were prepared by a sol-flux method. Characterization of TiO2/CNTs nanocomposite was performed...  相似文献   

14.
Thermal decomposition process of zinc hydroxide chloride (ZHC), Zn5(OH)8Cl2·H2O, prepared by a hydrothermal slow-cooling method has been investigated by simultaneous X-ray diffractometry and differential scanning calorimetry (XRD-DSC) and thermogravimetric-differential thermal analysis (TG-DTA) in a humidity-controlled atmosphere. ZHC was decomposed to ZnO through β-Zn(OH)Cl as the intermediate phase, leaving amorphous hydrated ZnCl2. In humid N2 with PH2O=4.5 and 10 kPa, the hydrolysis of residual ZnCl2 was accelerated and the theoretical amount of ZnO was obtained at lower temperatures than in dry N2, whereas significant weight loss was caused by vaporization of residual ZnCl2 in dry N2. ZnO formed by calcinations in a stagnant air atmosphere had the same morphology of the original ZHC crystals and consisted of the c-axis oriented column-like particle arrays. On the other hand, preferred orientation of ZnO was inhibited in the case of calcinations in 100% water vapor. A detailed thermal decomposition process of ZHC and the effect of water vapor on the crystal growth of ZnO are discussed.  相似文献   

15.
In this research, ultrasound irradiation as a simple method was used to produce boron nanostructures. Reaction conditions such as boron concentration and sonication time show important roles in the size, morphology and growth process of the final products. The boron nanostructures (nanoparticles and nanorods) were characterized by scanning electron microscopy, transmission electron microscopy, X-ray powder diffraction, small-angle X-ray scattering and inductively coupled plasma atomic emission spectroscopy techniques. Primary evaluation of results showed that nanoparticles and nanorods of boron successfully have been prepared with 25–40 and 50–100 nm average particle size, respectively. These nanostructures (nanoparticles and nanorods) were studied as an additive for promoting the thermal decomposition of ammonium perchlorate (AP) particles. Thermochemical decomposition behaviors of treated samples were characterized by thermal gravimetric analysis and differential scanning calorimetry techniques. Also, the kinetic parameters of thermal decomposition processes of pure and treated samples were obtained by nonisothermal methods proposed by Kissinger and Ozawa. However, boron nanoparticles with the smallest average particle size (25–40 nm) have the most significant catalytic effect including the decrease in decomposition temperature of AP + B nanocomposite by 100 °C, increase in the heat of decomposition from 580 to 1354 J g?1 and decrease in activation energy from 207 to 110 kJ mol?1.  相似文献   

16.
MXenes are novel graphene-like 2-D materials. Cu2O is an effective additive for thermal decomposition of ammonium perchlorate (AP). We reported the synthesis of MXene (Ti3C2), Cu2O and MXene-Cu2O respectively. The samples were characterized by means of X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). Results indicate that the MXene is composed of lots of nano-sheets and the thickness is 30 ± 10 nm, and Cu2O nanoparticles nucleate and grow heterogeneously directly on the surface of MXene. The effect of these MXene, Cu2O and MXene-Cu2O samples on the thermal decomposition of AP were investigated using TG-DSC. The results revealed that MXene-Cu2O have a great influence on the thermal decomposition of AP than that of pure MXene and Cu2O.  相似文献   

17.
The thermal decomposition kinetics of irradiated and unirradiated ammonium perchlorate and ammonium perchlorate powder-aluminum particle mixtures has been studied by determining decomposition gas pressurevs. heating time with samples at a controlled temperature Qualitatively the radiation induced changes are similar to those obtained in previous studies on ‘pure’ ammonium perchlorate. The induction period is shortened and the acceleratory and decay period rate constants are increased. The data have been analyzed using Avrami-Erofeev kinetics. The results for pure unirradiated material are in accord with published results. The activation energies for the induction, acceleratory and decay periods for pure pellets were found to be 133.5±6.7, 131.8±6.7 and 127.2±6.7 kJ·mol, respectively. Samples were exposed to either a single gamma-ray irradiation, fission neutron irradiation followed by a gamma-ray irradiation, or to a proton irradiation. When compared on an equal energy deposited basis, the fast neutron induced changes are appreciably larger than the gamma-ray changes. However, the proton induced changes are comparable or slightly more than the gamma-ray effects. Some, or all, of the fast neutron effects can be attributable to the concentrated radiation damage ‘spikes’ along the path of lattice atom recoils. It is likely that these become thermal decomposition sites when the crystals are heated. Protons create fewer spikes than fast neutrons. Overall, the results indicate that any ammonium perchlorate-aluminum propellant mixtures that may be exposed to radiation environments, such as used in this study, should be subjected to a thorough radiation effects analysis if reliable performance is required. In celebration of the 60th birthday of Dr. Andrew K. Galwey  相似文献   

18.
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.
Zusammenfassung Es wurde die Reaktionskinetik der thermischen Zersetzung von Ammoniumperchlorat (AP) in Gegenwart der Seltenerdenoxide Yttriumoxid (Y2O3) und Lanthanoxid (La2O3) als Katalysatoren untersucht. Zum Fitting der isothermen thermogravimetrischen Daten der katalysierten Zersetzung von AP läßt sich die Prout-Tompkins- und die Schrumpfwürfelgleichung erfolgreich anwenden. Die bei der katalytischen Zersetzung von AP freigesetzten Gase wurden durch IR-Spektroskopie untersucht. Der Mechanismus der katalytischen thermischen Zersetzung wurde auch vom Gesichtspunkt eines Elektronentransferprozesses aus besprochen.

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19.
Thermogravimetry-differential scanning calorimetry-mass spectrometry-Fourier transform infrared spectrometry(TG-DSC-MS-FTIR) simultaneous analysis was used to study the effects of 10.7 μm and 40 nm Al on the thermal decomposition of the Hexogen/ammonium perchlorate(RDX/AP,1/2,mass ratio) mixture.TG-DSC results show that there are two mass loss processes for the thermal decomposition of RDX/AP/Al.The first one is mainly ascribed to the thermal decomposition of RDX.The reaction rate of RDX/AP/10.7 μm Al is so fast that the apparent activation energy,calculated by model-free Friedman method,is negative,which is the same as that of RDX/AP.30%(mass fraction) 40 nm Al added in RDX/AP change the activation energy from negative to positive value.The second mass loss process of the RDX/AP/A1 mixture is ascribed to the thermal decomposition of AP.This process can be divided into three stages for RDX/AP with and without Al.The kinetics model is not changed in the presence of micro-sized Al,while it is changed from CnB/D1/D1 to CnB/D1/D4 after the addition of 40 nm Al to RDX/AP.The reaction rate constant of the first stage and the end temperature of the second stage decrease,while the end temperatures of the third stage increase in the presence of 40 nm Al.The MS-FTIR results show there is a competition between the formation reactions of HNCO,N2O and NO2 during the second mass loss process.  相似文献   

20.
A one-step electrochemical approach for synthesis of Pt nanoparticles/reduced graphene oxide(Pt/RGO) was demonstrated.Graphene oxide(GO) and chloroplatinic acid were reduced to RGO and Pt nanoparticles(Pt NPs) simultaneously,and Pt/RGO composite was deposited on the fluorine doped SnO 2 glass during the electrochemical reduction.The Pt/RGO composite was characterized by field emission-scanning electron microscopy,Raman spectroscopy and X-ray photoelectron spectroscopy,which confirmed the reduction of GO and chloroplatinic acid and the formation of Pt/RGO composite.In comparison with Pt NPs and RGO electrodes obtained by the same method,results of cyclic voltammetry and electrochemical impedance spectroscopy measurements showed that the composite electrode had higher catalytic activity and charge transfer rate.In addition,the composite electrode had proved to have better performance in DSSCs than the Pt NPs electrode,which showed the potential application in energy conversion.  相似文献   

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