Ammonium perchlorate

About: Ammonium perchlorate is a research topic. Over the lifetime, 2359 publications have been published within this topic receiving 33412 citations. The topic is also known as: AP.

Effect of manganese dioxide on the thermal decomposition of ammonium perchlorate

Abstract: Thermal decomposition of powdered ammonium perchlorate, catalysed by manganese dioxide (MnO2), has been studied in the low concentration ranges of the catalyst. MnO2 sensitises the thermal decomposition of ammonium perchlorate. The activation energy estimations of catalysed ammonium perchlorate show that the value is about 30 kcal/mol throughout the low and the high temperature regions whereas uncatalysed ammonium perchlorate gives two activation energies, 20 kcal/mol in the low temperature region (280–320°C) and 60 kcal/mol in the higher temperature region (350–390°C). This behaviour has been explained on the basis of an electron transfer process. The effectiveness of MnO2 in the thermal decomposition further increases on pre-heating the sample at 50°C for two weeks; manganese ions enter the ammonium perchlorate lattice during the process of pre-heating.

3,4,5-Trinitro-1-(nitromethyl)-1H-pyrazole (TNNMP): a perchlorate free high energy density oxidizer with high thermal stability

Abstract: A superior oxidizer, a derivative of trinitropyrazole, 3,4,5-trinitro-1-(nitromethyl)-1H-pyrazole (TNNMP), was obtained in good yield by the reaction of ammonium 4-amino-3,5-dinitropyrazolate with bromonitromethane followed by oxidation with a mixture of H2O2/H2SO4. Characterization of TNNMP shows that in addition to having good oxygen balance (+18.3%) and detonation performance (Dv = 8858 m s−1; P = 35.1 GPa), it concomitantly has high thermal stability (Td = 202 °C) and acceptable sensitivities (IS = 14 J; FS = 120 N). These attractive properties suggest TNNMP as a promising perchlorate free high energy density oxidizer and a potential replacement for ammonium perchlorate.

Electrochemical dechlorination of chlorinated hydrocarbons: Electrochemical reduction of chloroform in acetonitrile/water mixtures at high current density

Abstract: Electrochemical reduction of chloroform was studied in 0.1 M (1 M = 1 mol dm−3) tetraethyl ammonium perchlorate solutions of acetonitrile–water mixture using various metal electrodes. High water concentration (1 M) promoted the electrolysis with the products mainly CH4 and CH2Cl2. The partial current density of CH4 formation amounted to 0.3 A cm−2 at an Ag electrode.

Time-resolved size, velocity, and temperature statistics of aluminum combustion in solid rocket propellants

Abstract: The study of time-resolved aluminum combustion mechanisms is essential for understanding the deflagration of ammonium perchlorate-based metalized solid rocket propellants. In order to gain further insight into the performance of solid propellants, spatially and temporally resolved aluminum agglomerate particle dynamics are obtained by combining digital in-line holography (DIH) and two-color imaging pyrometry with high-speed acquisition at up to 20 kHz. Holography is used to find the size, three-dimensional position, and three-dimensional velocity evolution of agglomerates over time. Then, the temperature of individual particles is extracted from the high-speed imaging pyrometry. This diagnostic technique not only produces joint size, position, velocity, and temperature statistics over time, but also captures the combustion histories for thousands of particles per experiment. For the first time, these spatial and temporal dynamics of individual aluminum particulates are examined while they travel away from the propellant surface. Initial results demonstrate how aluminum agglomerates of similar size exhibit varying initial acceleration but similar steady-state velocities. Average velocity also decreases as particle size increases, which is consistent with viscous flow dynamics of small particles in convective flow. As they move further away from the propellant surface, large agglomerates also show a convergence to an average projected temperature between the melting point of aluminum oxide and the boiling point of aluminum. The average projected particle surface temperatures were measured to be 2494 ± 231 K. The method outlined in this work demonstrates a new capability for gathering the evolution of joint statistics for aluminum agglomerates in solid-rocket propellants. Future applications of this technique can be used to evaluate the detailed combustion mechanisms of existing or new propellant formulations.

Ammonium Perchlorate Combustion: Effects of Sample Preparation; Ingredient Type; and Pressure, Temperature and Acceleration Environments

Abstract: Differences in ammonium perchlorate (AP) combustion behavior as evidenced by the effects of pressure, sample temperature and acceleration environments on burning rate are shown for samples prepared in various manners. The sample preparation parameters investigated include pellet compaction time and pressure, the particle sizes of the AP powder from which samples were pressed, and the type of AP (ultra-pure, propellant grade, and propellant grade with conditioners) from which the pellets were made.