Thermal Decomposition Of Ammonium Perchlorate Research Articles

Dye Decorated Ammonium Perchlorate with Fast Decomposition and High Safety Performance

AbstractEnhancing the thermal decomposition efficiency and safety of ammonium perchlorate (AP) is of far‐reaching significance in composite propellants. Most catalysts act well on the thermal decomposition of AP, however, synergistically achievements of fastened decomposition and improved mechanical safety are still in challenge. Herein, neutral red (NR) is selected from typical dyes through theoretical calculations, acting as an organic decoration of AP crystal with improved performances. Among the four organic dyes, NR demonstrated the highest adsorption energy and evident charge transfer at the interface. Following preparations through a freeze‐drying technique obtained a quasi‐homogeneous energetic composite (NR‐AP‐5%). The large interaction force between NR and AP promoted the rupture of chemical bonds between Cl and O as proved by TG‐MS, showing excellent energy‐release performance with the decreased exothermic peak from 437.0 to 355.5 °C. Correspondingly, the activation energy is reduced from 213.59 to 107.72 kJ mol−1, with largely increased heat release from 447.29 to 1014.86 J g−1. In addition, the inert decoration of NR endowed considerable advances in the safety performances of AP, achieving remarkably improved impact and friction sensitivity of 35 J and 288 N, respectively. This unique assembly structure provides a novel strategy to achieve high‐effective catalysis for functional propellants.

Comprehensive revelation of the influence mechanism for the thermal decomposition of ammonium perchlorate by ammonium oxalate

Rate inhibitors for combustion are crucial to decrease the burning rate and prolong the working time of solid propellants. Ammonium oxalate (AO), the most frequently utilized and effective rate inhibitor in propellants, faces the challenge of an unclear influence mechanism regarding ammonium perchlorate (AP). Therefore, it is necessary to elucidate the influence mechanism of AO on the thermal decomposition of AP. This study fabricated AP/AO composites with varying AO content via wet milling, the structural, thermal decomposition processes and products of these composites were investigated. Additionally, the adsorption between AP and NH3 was simulated. The findings indicate that the inclusion of AO inhibits the low-temperature decomposition (LTD) of AP while enhancing its high-temperature decomposition (HTD). Furthermore, it was observed that the heat release of AP/AO composites was lower than that of AP. The Gibbs free energy (ΔG≠) of the AP/AO composites exceeded that of the AP at the LTD stage and was lower than that of AP at the HTD stage. Further study using molecular dynamics simulations revealed that as the increase of NH3 concentration, its adsorption on the AP surface intensifies during LTD, inhibiting the forward progress of the AP decomposition reaction. However, NH3 molecules desorbed from the AP surface and actively participated in gas-phase reactions with increasing temperature, thereby promoting the HTD of AP. This work is helpful to fully understanding the mechanism of AO in the process of the LTD and the HTD of AP but also contributes to the exploration of novel inhibitors and advances the development of low-burning rate solid propellants.

Green synthesis of perovskite-type FeMnO3 nanoparticles: Study of its electrochemical hydrogen storage and catalytic activity on the thermal decomposition of ammonium perchlorate

Perovskite-based mixed metal oxides have become a promising material as efficient catalysts and electrocatalysts for various energy storage-related and fuel applications in modern scientific society. This study is the first attempt to explore the catalyst and electrocatalyst application of iron manganese oxide (FeMnO3) perovskite. The pure FeMnO3 nanoparticles (NPs) were synthesized using a green method by Aloe vera extract as a capping agent. The cubic crystal structure, nanosized particle, purity, mesoporous feature and ferromagnetic properties of FeMnO3 NPs were confirmed using XRD, FT-IR, FESEM-EDS mapping, BET, and VSM analysis. The electrocatalyst properties of the sample were measured using cyclic voltammetry (CV), chronopotentiometry (CP), and electrochemical impedance spectroscopy (EIS) techniques. The results showed that the specific capacitance value and hydrogen storage capacity of FeMnO3 NPs were about 382.5 Fg−1 and 2622 mAhg−1 in the aqueous alkaline medium (3 M KOH), respectively. Additionally, the catalytic activity of the sample on the thermal decomposition of ammonium perchlorate (AP) was analyzed using differential scanning calorimetry (DSC) and thermogravimetry (TGA) instruments. The results revealed that FeMnO3 NPs enhanced the released heat of AP from 525 to 1760 Jg−1 and reduced the decomposition temperature from 458 to 381 °C.

MoS2 stabilize Ti3C2 MXene for excellent catalytic effect of thermal decomposition of ammonium perchlorate

Ammonium perchlorate (AP), the most widely used oxidizer in energetic materials, is crucial for studying catalytic thermal decomposition. Newly discovered Ti3C2 MXene and MoS2 demonstrating promising prospects in the field of the pyrolysis catalyst in AP. In this study, we employed a hydrothermal method to anchor nano-sized MoS2 in situ on the surface of Ti3C2 MXene, leading to the fabrication of MoS2-Ti3C2 nanocomposites. Various characterizations indicated that MoS2 was attached to the surface and edges of Ti3C2, thereby enhancing the stability and conductivity. Results revealed that upon the addition of 4 wt% MoS2-Ti3C2, the low-temperature decomposition peak of AP reduced from 331.2 °C to 296.6 °C, while the high-temperature decomposition peak advanced from 427.5 °C to 387.1 °C, showing a superior catalytic effect compared to the individual MoS2 or Ti3C2. Additionally, the catalytic mechanism of MoS2-Ti3C2 on the thermal decomposition of AP may involve enhanced electrical conductivity, facilitating rapid proton transfer (H+), accelerated redox reactions, prompt release of gas products, and thereby expediting the progression of the decomposition reaction. Consequently, it can be anticipated that anchoring MoS2 on the surface of Ti3C2 represents an effective strategy for enhancing the catalytic activity of Ti3C2 MXene towards the thermal decomposition of AP.

The bimetallic 3,5-dinitrobenzoate composites: A flexible-synergistic catalysts for high-performance decomposition of ammonium perchlorate

Composites of metal complexes have catalytic effects on the thermal decomposition of ammonium perchlorate (AP), while the kinetics and mechanism studies of the processes are seldom mentioned. Here, composite microspheres of cupric 3,5-dinitrobenzoate and cobalt 3,5-dinitrobenzoate [(3,5-DNB)Cox•Cuy] were synthesized and employed to research the kinetics and mechanism of AP catalytic decomposition. The decomposition peak temperature of AP in the presence of the (3,5-DNB)Cox•Cuy microspheres decreased from 403 °C (pure AP) to 288 °C, and the released heat increased by 384.5–745.6 J/g. Notably, the (3,5-DNB)Cox•Cuy microspheres significantly improved the kinetic rate constant by 1.83–37.75 times. The (3,5-DNB)Cox•Cuy microspheres exhibited higher activity than their corresponding single components for the thermal decomposition of AP, indicating excellent synergistic effects and proposing a possible mechanism. Understanding the kinetics and mechanism of the catalytic process developed in this study could further improve the decomposition performance of AP.

Ammonium perchlorate catalyzed with novel n-Al modified on ZIF-67 with silane coupling agent: Superior catalytic activity, advanced decomposition kinetics and mechanisms

Ammonium perchlorate (AP) is commonly utilized as an oxidizer in composite solid propellants (CSPs), and the thermal decomposition of AP has a significant impact on the combustion behaviour of CSPs. Aluminum nanoparticles (n-Al) as a prospective metal fuel have received a lot of interest, however properly extracting energy from n-Al remains a great challenge. Native oxide layer limits the energetic performance of n-Al by impeding sufficient combustion and slowing down mass/heat transport. Development of the high energy storage based on metastable intermolecular composite (MIC) is always a desirable way. This group of hybrid materials uses zeolitic imidazole framework (ZIF) as the precursors of the metal oxides as the oxidizers in conventional nanothermite. Coating n-Al on the surface of ZIF-67 with a silane coupling agent to erase or disturb the oxide layer on the n-Al surface improves n-Al combustion. n-Al@ZIF-67 was synthesized and integrated into AP matrix. The catalytic activity of n-Al@ZIF-67 on AP decomposition was assessed via DSC and TGA/DTG. Whereas n-Al@ZIF-67/AP nanocomposite demonstrated decomposition enthalpy of 2350 J/g; pure AP demonstrated 836 J/g, ZIF-67/AP demonstrated 1680 J/g, and n-Al/AP demonstrated 1170 J/g. While Al@ZIF-67/AP nanocomposite demonstrated one decomposition temperature at 327 oC; pure AP decompose at two decomposition stages at 298 oC, and 453 oC. n-Al@ZIF-67/AP showed a violent reaction with high intensity of flame, and micro-explosion occurred due to rapidly disrupted oxide layer that covered Al core. Decomposition kinetics was investigated. n-Al@ZIF-67/AP demonstrated apparent activation energy of 125.3 ± 1.23 kJ/mol compared with 173.16 ± 1.95 kJ/mol for pure AP. Co3O4 NPs as the combustion product from ZIF-67 can expose active surface sites; the ability of adsorption of released NH3 gas, which inhibition AP from decomposition, offering efficient combustion. This work provides a new strategy for advanced CSPs by introducing ZIF-67 to construct bifunctional properties for AP decomposition, and n-Al combustion.

Evaluation of the synergistic effect of magnetic nanoparticles and Ferrocene-Based 1,2,3-Triazolyl compounds as burning rate catalysts for solid rocket Motors

This work reports the synthesis, characterization, and application of promising nanocatalysts on the thermal decomposition of ammonium perchlorate (AP). Magnetite nanoparticles were functionalized with Ferrocene-derivative groups through chemical and physical methods to obtain these composite materials. The characterization was done using TEM, FTIR, VSM, and TGA techniques. The composite material MNP-Fc2I causes a decrease in the high-temperature decomposition (HTD) of AP to 357 °C. On the other hand, the MNP-Fc1 obtained the lowest activation energy (138 kJ·mol−1), indicating that the reaction may initiate at a relatively high temperature due to the need to overcome the activation energy barrier; once it begins, it proceeds with reduced energy requirements. Furthermore, performing ion exchange with energetic anions results in a decrease in the decomposition temperature of AP for the MNP-Fc1(N3) and MNP-Fc1(DCA) catalysts.

Preparation, characterization and thermal properties of nitrographene coated aluminum powder

AbstractAluminum powder is commonly used as a metal fuel additive in composite solid propellants. However, its tendency to agglomerate during combustion can lead to two‐phase flow losses, negatively impacting its energy performance. To address this issue and enhance the combustion performance of aluminum powder, nitrated graphene oxide (NGO) was developed to improve aluminum dispersion and optimize its energy characteristics. Various analytical techniques were employed to examine its properties, including Fourier‐transform infrared spectroscopy (FT‐IR), scanning electron microscopy (SEM), X‐ray photoelectron spectroscopy (XPS), elemental analysis (EA), differential scanning calorimetry (DSC), and thermogravimetric analysis (TG). Al/NGO composite was prepared using a solution‐assisted method in N, N‐dimethylformamide (DMF) and characterized by SEM, XPS and X‐ray diffraction (XRD). The ignition characteristics and heat of combustion of Al/NGO powder were measured using a laser igniter and an oxygen bomb calorimetry. The appropriate mass ratios of NGO coating had positive effects on the ignition and combustion of Al. Specially, 4 % NGO coating reduced Al ignition energy by 46.5 % and increased the Al combustion efficiency by 22.0 %. Moreover, the catalytic effect of Al/NGO on the thermal decomposition of ammonium perchlorate (AP) was investigated using differential thermal analysis (DTA). Results showed that two‐stage pyrolysis paths of AP tended to merge into a single pyrolysis process when Al/NGO4 % was added. The most favorable catalytic effect on AP′s thermal decomposition process was produced with the addition of 10 % Al/NGO4 %, reducing the activation energy by Kissinger equation for high‐temperature decomposition to 107.7 kJ mol−1. These findings may provide valuable insight for enhancing the performance of aluminum powder in energetic materials through NGO modification.

Construction of nanoflowers combustion catalyst NiO@g-C3N4 for improving thermal decomposition performance of AP

Thermal decomposition of ammonium perchlorate (AP) typically requires high temperatures and activation energy, but the introduction of combustion catalysts will improve its thermal decomposition performance. Therefore, it is crucial to rationally design combustion catalysts for enhancing the thermal decomposition performance of AP. Herein, 3D NiO nanoflowers@2D graphite-phase carbon nitride (g-C3N4) nanosheets (NiO@x%CN, x = 1, 3, 5, 7, 9) composite catalysts were constructed by solvothermal and calcination methods, and characterized by a series of analyses. NiO@5%CN displayed the best ability to catalyze the thermal decomposition of AP, which reduced the high decomposition temperature of AP by 113.8 °C and the activation energy by 21.67 kJ mol−1. The combustion rate of NiO@5%CN-CSP has increased by 118 % compared to that of composite solid propellants. This work provides a new insight for the design of NiO-based high-efficiency combustion catalysts.

Model-free kinetic analysis of multi-step thermal decomposition of ammonium perchlorate coated with reduced graphene oxide

Model-free kinetic analysis of multi-step thermal decomposition of ammonium perchlorate coated with reduced graphene oxide

Cu/Carbon Aerogels Derived from HKUST-1 for the Thermal Decomposition of Ammonium Perchlorate

Cu/Carbon Aerogels Derived from HKUST-1 for the Thermal Decomposition of Ammonium Perchlorate

Preparation of Zn-Co Bimetallic Catalysts and Their Catalytic Properties for Thermal Decomposition of Ammonium Perchlorate.

This research delves into the preparation of heteronuclear bimetallic catalysts and explores their catalytic properties in the thermal decomposition of ammonium perchlorate (AP). The study's central focus is on enhancing the thermal decomposition characteristics of AP and, consequently, the combustion performance of composite solid propellants. The synthesized materials underwent structural characterization by XRD, XPS, SEM, and FTIR. Catalytic properties were examined using DTA tests. Notably, catalysts derived from calcination at 500 °C exhibited heightened catalytic activity. They advanced the pyrolysis temperature by 135.4 °C and reduced the activation energy by 82.38 kJ/mol compared with pure AP. To further elucidate the decomposition mechanism of AP, the investigation also employed a combined approach involving DSC-TG-FTIR-MS analysis.

Based on the strong oxidant AP adjustment strategy to obtain Al/AP@PVDF composite material with excellent energy release performance

In this paper, ammonium perchlorate (AP) as a strong oxidant has been added into Al/polyvinylidene difluoride (PVDF) nanothermites. Based on homogeneous structure of PVDF, shorter reaction contact between components can be obtained for more outstanding ignition and combustion performance. Water contact angle experiments were conducted to evaluate the hydrophobicity of the composite films, indicating that the suitability of composite material has enhanced under wet environment. According to TG-DSC results, the thermal decomposition of AP can improve the whole heat release process, which theoretically has excellent combustion performance advantages. Constant volume pressure tests were conducted to assess the energy release properties of the films compared with Al@PVDF films. Combustion performance in air was evaluated by employing optical sensors and a high-speed camera to measure factors such as the ignition delay time, light intensity and combustion flame propagation. After adding 15 % AP, the maximum pressure of Al/AP@PVDF film is 0.0960 Mpa, and that of Al@PVDF film is 0.0805 Mpa. The maximum pressure of the film is increased by nearly 19.25 %. Compared with Al@PVDF film, the ignition delay time of Al/AP@PVDF film is shortened by 45 ms, and the light intensity is increased by nearly 93.39 %. However, excessive AP content adversely impacted film formation efficiency, leading to the deterioration of various properties. Therefore, an optimal AP content of approximately 15 % in Al/AP@PVDF system was finally identified.

Energetic transition metal complexes based on 1‐allylimidazole and nitrocyanamide: Syntheses, characterizations and catalytic performances on the thermal decomposition of ammonium perchlorate

AbstractTo explore combustion catalysts for solid propellants, four novel energetic coordination compounds were prepared with the anion of nitrocyanamide (NCA) as the ligand and 1‐allyl‐imidazole (AIM) as the ligand, and transition metals Mn, Co, Ni, and Cu as the central ions. The structures of these compounds were [Mn(AIM)4] (NCA)2 (1), [Co(AIM)4](NCA)2 (2), [Ni(AIM)4](NCA)2 (3), [Cu(AIM)4](NCA)2 (4). The results showed that all of the compounds possessed high energy density, and compound 2 had a mass energy density (Eg) of 17.9 kJ g−1 and a volume energy density (Ev) of 25.59 kJ cm−3. The catalytic effect of these compounds on the thermal decomposition of ammonium perchlorate (AP) was studied using DSC. The addition of 5 % catalyst to AP samples advanced the high‐temperature decomposition temperature and significantly increased the heat release. Compound 4 exhibited the best catalytic performance, with an increased heat release of 1739 J g−1, decomposition temperature advanced by 88.2 °C, and activation energy reduced to 74.74 kJ mol−1. These results demonstrate the potential of these compounds as combustion catalysts for solid propellants.

Mn/carbon aerogels derived from the water-induced self-assembly of UIO-66 (Mn) for the thermal decomposition of ammonium perchlorate.

In solid propellants, combustion catalysts play a crucial role. Here, we introduce a convenient method for the self-assembly of UIO-66 (Mn) in the presence of water, leading to the preparation of Mn/C aerogels. The aerogels were successfully utilized in the thermocatalytic decomposition of ammonium perchlorate (AP). The results indicate that the incorporation of 2% mass fraction of Mn/C aerogels enhances the peak temperature of AP decomposition by approximately 87.5°C. Mn/C aerogels demonstrate excellent catalytic performance. In combination with kinetics, we propose a thermal catalytic mechanism.

Synthesis of Cu-MOF-derived complex copper–chromium oxides and their catalytic study on the thermal decomposition of ammonium perchlorate

In this work, a series of complex copper-chromium oxides were prepared by adjusting the molar ratio of Cr3+/Cu2+ using MOF-199 as a template. X-ray diffraction (XRD), scanning electron microscopy (SEM), Transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) were used to characterize the structure, microscopic morphology and valence information of the samples. The specific surface area of the sample was estimated by the Brunauer-Emmett-Teller method (BET), and the pore size parameters of the sample were obtained by using the Barrett-Joyner-Halenda (BJH) model. The effect of the samples on the thermal decomposition process of ammonium perchlorate (AP) was investigated by differential scanning calorimetry-thermogravimetric analysis. The results show that the copper and chromium oxides in the complex exhibit good catalytic effects. Among them, CuCr(0.8) had the best catalytic effect, reducing the peak pyrolysis temperature of AP by 95.7 °C, increasing the heat release by 817 J/g, and reducing the reaction activation energy by 62.4 kJ/mol. Real-time FTIR was used to characterize the gas products during the thermal decomposition of AP, and the gas products of AP with CuCr(0.8) catalyst were different from those of pure AP, which may also be the reason for the increase of AP heat release after adding CuCr(0.8) catalyst.

Evaluation of the Combustion Properties and Catalytic Activity of MgAlB Energetic Ternary Particles

ABSTRACT Boron powder possesses significant potential for use as a combustible agent in energetic materials, owing to its superior combustion thermodynamic properties. However, the powder’s tendency to form an oxide layer on its surface results in delayed ignition, reduced combustion efficiency, and compromised energy advantage. To enhance the ignition and combustion properties of boron powder, we prepared boron-based energetic composites containing flammable metals (MgxAl1-xB2) through high-temperature sintering. These were then characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), energy dispersive spectroscopy (EDS). The combustion heat of these alloy powders were measured using an oxygen bomb calorimeter, while their catalytic performance on the thermal decomposition of ammonium perchlorate (AP) was analyzed using differential scanning calorimetry (DSC) and differential thermal analysis (DTA). The results indicate that compared with boron, the MgxAl1-xB2 powders are more flammable, require less oxygen, exhibit a higher combustion efficiency and exothermic advantage. Especially, the Mg0.9Al0.1B2 and MgB2 alloy exhibit optimal combustion heat values of 39,094.92 and 37,693.90 J·g−1, respectively. They significantly enhance the thermal decomposition of AP and reduce the activation energy by over 20%.

Bioinspired Fabrication of an Insensitive Ammonium Perchlorate Core-Shell Composite with Polydopamine Coating.

In this research, an ammonium perchlorate/polydopamine (AP/PDA) core-shell composite was prepared in a non-aqueous solution to reduce the mechanical sensitivity of ammonium perchlorate (AP). The result showed that the AP/PDA core-shell composite could be successfully constructed in ethyl acetate solution with an AP recovery rate that reached 86%. The mechanical sensitivity of the obtained AP/PDA core-shell composite was significantly reduced with a PDA content of only 0.76%. The DSC and TG also indicated that the coating of PDA showed catalytic activity in the thermal decomposition of AP with a lower decomposition temperature and a decreased Ea value of AP. Thus, this study proposed a simple strategy for achieving a good balanced between harnessing the energy and ensuring the safety of ammonium perchlorate by significantly reducing its mechanical sensitivity by using a very low polydopamine coating layer content, and this shows great potential for the design and fabrication of insensitive energetic composites for use in propellants.

Microflower-like Fe-Co-MOF with enhanced catalytic performance for decomposition of ammonium perchlorate and combustion of ammonium perchlorate-based composite propellants

Ammonium perchlorate (AP) serves as a crucial component in solid propellants. Enhancing its thermal decomposition with catalysts improves the combustion performance of solid propellants significantly. To enhance the catalytic performance of metal-organic frameworks (MOFs) on AP, this study controlled the morphology of MOFs by adding metal atoms, resulting in a Fe-Co-MOF catalyst with higher specific surface area and dual-metal synergistic effect. The catalytic effect of the catalyst on AP was investigated using DSC and TG-IR, followed by studying its influence on the combustion performance of AP-based composite propellants. The results show that the introduction of 5% Fe-Co-MOF reduced the decomposition temperature of AP to 298.6 °C, decreased the activation energy to 151.6 kJ mol-1, and increased the heat release by 110.6%. Additionally, the ignition delay of the propellant decreased by 71 ms, and the combustion rate increased by 43.8%. Mechanistic studies demonstrate that the abundant catalytic sites and oxygen vacancies of Fe-Co-MOF facilitate the charge transfer rate during the AP thermal decomposition process and promote the increase in AP heat release by suppressing the high-temperature conversion of N2O. This research paves the way for enhancing the application of MOF materials in AP-based solid propellants.

Catalytic properties of 3D flower-likeMgCo2O4/MXene composites for the thermal decomposition of ammonium perchlorate by one-pot synthesis

The catalytic active sites of the materials have a major role in the catalytic activity of nanocatalytic materials for the heat thermal decomposition of ammonium perchlorate. By adopting one-pot strategy to load MgCo2O4 onto MXene nanosheets, we were able to create highly dispersed MgCo2O4/MXene composites that improved the dispersion of the nanoparticles and increased the catalytic active sites. The MgCo2O4/MXene catalytic active sites were clearly optimized (Specific surface area increased from 115.4 of MgCo2O4 to 168.8 m2·g−1), according to the BET results. The performance tests demonstrated that the MgCo2O4/MXene composite effectively decreased the thermal decomposition temperature of AP, and the MgCo2O4/MXene composite significantly reduced the peak decomposition temperature of AP by 208.3 °C (from 471.2 °C of pure AP to 262.9 °C). The decomposition heat of AP increased from 782 J·g−1 of pure AP to 1453 J·g−1. In addition, the apparent activation energy of AP dropped from 296.19 kJ·mol−1 to 119.48 kJ·mol−1. Application of MgCo2O4/MXene composite to AP/HTPB-based composite solid propellants (CSPs) for combustion experiments resulted in an appreciable reduction in ignition delay time of ∼ 45 ms (from ∼ 51 ms to ∼ 6 ms). The highly dispersed MgCo2O4/MXene composite was a positive catalyst for AP-based composite solid propellant.