JOURNAL OF CHEMICAL AND ENGINEERING DATA
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2012
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IF 1.693
Yuan-Yuan Che,Jian Shen,Jun-Chao Zhou,Chao-Hong He
The thermal conductivity of ammonium sulfate + water, ammonium nitrate + water, and ammonium sulfate + ammonium nitrate + water is of great significance in the national defense industry and military engineering for manufacturing of various energetic chemicals. The measurements, covering a temperature range from (278.15 to 333.15) K, have been performed by a transient hot-wire technique over a wide range of concentrations. The densities of ternary aqueous solutions of ammonium sulfate + ammonium nitrate are also presented at the same temperature covering different portions of ammonium sulfate and ammonium nitrate. The thermal conductivities of binary aqueous solutions of ammonium salts are correlated by polynomial functions in terms of temperature and weight fraction for the purpose of interpolation. The Aseyev equation in terms of weight fraction is also used to represent the thermal conductivities of ternary mixtures of these compounds. The ideal mixing rule of Young has been successfully applied to correlate the ternary densities of aqueous ammonium sulfate + ammonium nitrate solutions based on relevant binary solution properties. The agreement between the correlation and the experimental data is pretty good.
研究领域:
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
Arabian Journal of Chemistry
·
2018
·
IF 2.969
Baha I. Elzaki,Yue Jun Zhang
Ammonium nitrate surface is extremely hygroscopic, due to high energy on its surface which increases the potential of the molecules to absorb moisture from the surrounding environment. Ammonium nitrate particles were modified using second coating process with myristic acid in the different amount. The hygroscopicity was tested for ammonium nitrate with and without coating. Fourier transform infrared (FTIR) and scanning electron microscopy (SEM) were used to characterize the surface of coated and uncoated ammonium nitrate. Meanwhile, the method determined mass ratio of coating layer was improved to achieve more accuracy. In addition, focused ion beam technique was used to determine the thickness of coating layer. The results indicated that by using second coating modification method of surfactant adsorption, the anti-hygroscopicity performance of coated samples was significantly improved. The result showed that the decline of the absorption moisture rate was 40.57%, and the mass ratio of the coating layer was 1.42%. These results suggest that the second coating process employed could provide the well fundamental for the further anti-hygroscopic surface modification of ammonium nitrate particles coated by surfactants.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ATMOSPHERIC ENVIRONMENT
·
2022
·
IF 5.755
Na Wang,Yaxin Guo,Jiarong Li,Shufeng Pang,Yunhong Zhang
Water-soluble amino acids have been confirmed as effective cloud condensation nuclei (CCN) materials. While their influence on the hygroscopicity of nitrates is still scarcely known. In this work, ammonium nitrate (AN) was mixed with glycine and alanine at various mole ratios to form internally mixed particles deposited onto a solid substrate, whose hygroscopic properties and phase states of ingredients were investigated using microscope and attenuated total reflection-Fourier transformed infrared spectroscopy (ATR-FTIR). For mixed AN/amino acid particles with abundant inorganic, AN crystallizes at lower RH than that of pure AN, while deliquescence relative humidities (DRHs) were close to pure AN. On hydration, the mixture composed of bis(amino acid) nitrates and mono(amino acid) nitrates formed at 14.6–60.8% RH and 23.6%–60.0% RH for AN/glycine and AN/alanine particles, respectively. When the inorganic and organic components were mixed with equal mole ratio, gradual water uptake and release took place due to the hygroscopic interplay between components. In the mixed particles with abundant amino acids, glycine and alanine still kept solid at highest RH on hydration. Hydrogen bonding interaction should account for the mutual suppression on individual crystal formation. The present hygroscopic study would help people understanding cloud condensation nuclei (CCN) ability of amino acids in atmosphere.
研究领域:
大气科学
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化学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 79
·64358-64367
·
IF 3.84
Jian Cheng,Yan Dong,Hui Ma,Lixia Li,Zuliang Liu,Fengqi Zhao,Siyu Xu
A one-dimensional energetic complex (Na[CL-14·2H2O]) constructed from sodium and 5,7-diamino-4,6-dinitrobenzofuroxan (CL-14) was synthesized, and its crystal structure was analyzed by X-ray diffraction. The crystal belongs to a monoclinic system with space group P21/c. The complex possesses a one-dimensional coordination framework based on the [ONaN]n chain, which might result in its low sensitivity and high heat resistant. The thermal decomposition mechanism of Na[CL-14·2H2O] was predicted by means of TG-DSC, TG-MS and FTIR analyses. The thermal decomposition of Na[CL-14·2H2O] contains one endothermic and one exothermic processes in the temperature range of 25–500 °C with NaNCO, Na2CO3, H2O, NO and CO2 as the final products. The non-isothermal kinetic and thermodynamic parameters for the first exothermic process of the Na[CL-14·2H2O] have been studied, with the apparent activation energy, pre-exponential factor, entropy of activation, enthalpy of activation and free energy of activation of 280.7 kJ mol−1, 57.8, 282.7 J mol−1 K−1, 276.2 kJ mol−1 and 154.8 kJ mol−1, respectively. The impact sensitivity and friction sensitivity of Na[CL-14·2H2O] was tested according to general methods, with the values of 27 J and 360 N, respectively. Na[CL-14·2H2O] has been investigated as an energetic catalyst in ammonium nitrate (AN) by means of TG-DTG, TG-MS, DSC and extent of conversion (α)–T kinetic curve analyses. And the thermal kinetic constants for the catalytic and noncatalytic decomposition of AN samples were calculated using Kissinger's and Ozawa–Doyle's equations. The possible catalytic mechanism was also discussed and proposed. The results show that Na[CL-14·2H2O] decreases the peak temperature and activation energy value of the complete decomposition process for AN by 41.3 °C and 10.9 kJ mol−1, respectively. Furthermore, the thermal decomposition of AN in the presence of Na[CL-14·2H2O] starts at significantly lower temperature (about 30 °C) than that of pure AN. Apparently, Na[CL-14·2H2O] could be incorporated as a potential energetic catalyst in AN-based propellants.
研究领域:
化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED THERMAL ENGINEERING
·
2020
·
IF 4.725
Qi Sun,Lin Jiang,Huiqi Cao,Jinhua Sun,Ganbin Liu
Statistics have indicated that industrial accidents of ammonium nitrate were primarily caused by uncontrolled external fires where heating was dominantly controlled by radiation, and yet existing studies at milligram scale cannot fully simulate the real fire scenarios. To explore the pyrolysis behavior in typical fires, this study conducted thermal radiation experiments using pure ammonium nitrate, and its mixtures with copper oxide and sulfuric acid. Different from the pyrolysis process identified in milligram scale tests, the bench-scale pyrolysis of ammonium nitrate under radiation consisted of four stages. Pyrolysis structure model of each stage was built to reveal the differences in dominated thermal behavior. Results indicated that two additives had different thermo-chemical effects on pyrolysis of ammonium nitrate. Sulfuric acid accelerated the reaction rate of each stage by generating catalytic nitric acid; copper oxide reduced the number of reaction stages into three via surface absorptions. The time and mass loss rate of different stages were determined. Recommendations on effective emergency response were made to prevent the transition of slow decomposition into fast decomposition, and thus to intervene the fire-induced domino effect of ammonium nitrate. This study helps to understand the pyrolysis behavior of ammonium nitrate under fire exposure, and provides insights for pyrolysis modeling and firefighting in industry of interest.
研究领域:
化学工程
·
安全科学
✓ 已验证
DOI
高影响因子
JOURNAL OF DISPERSION SCIENCE AND TECHNOLOGY
·
2017
·
IF 1.591
Yang Wang,Xu-guang Wang
The instability of emulsion explosive matrices is mainly due to the crystallization of interphases as oversaturated aqueous solutions of nitrate salts. The principal features of crystallization for this type of emulsion have been previously studied; however, there is no consensus regarding the mechanism of crystallization for an emulsion explosive matrix. This study is devoted to the investigation of the crystallization behavior of interphase droplets. By monitoring the mass change of emulsions during their aging process, it was found that the mass of the emulsions remains almost constant and that water still completely existed in the emulsion system after crystallization of the interphase droplets. The ammonium nitrate (NH4NO3) crystals in the emulsion explosive matrices were then separated successfully using a simple method. The thermal behavior of pure NH4NO3 and crystals in the emulsion explosive matrices was studied by differential scanning calorimetry-thermogravimetric analysis (DSC-TG) at a heating rate of 10 K/min. The experimental results show that the thermal behavior of the crystals in the emulsions was exactly the same as for pure NH4NO3, meaning that only NH4NO3 crystallized from the emulsion explosive matrices with no water crystals. Thus, it could be concluded that after crystallization of the dispersed drops in the emulsion explosive matrices, pure NH4NO3 crystals and new smaller droplets were produced.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2025
·
IF 5.4
Shimin Zhang,Wenqing Li,Songchao Shi,Jingwen Guan,Baoyun Ye,Jingyu Wang,Chongwei An,Chuanhao Xu
Ammonium dinitramide (ADN), an ideal oxidizer for solid propellants, possesses the advantages of high energy, and gas cleanliness. However, addressing its high moisture absorption and low safety is crucial for ADN to realize its chemical potential. In this study, novel energy-containing particles ADN@GO with core-shell structure and ADN@GO@NC with double-shell structure were prepared using 2D carbon nanomaterials as surfactants by Pickering emulsification method. The stability of the emulsions and the properties of these composites, including morphology, structure, thermal properties, moisture absorption, mechanical sensibility, and energy release were systematically investigated. The results show that the ADN-based composites had low moisture absorption and high safety. ADN@GO@NC, with a double-shell structure, exhibited a regular spherical morphology, with GO and NC adhering to the surface of the ADN crystals. Importantly, the Pickering emulsification process preserved the crystal structure of ADN. The incorporation of GO and NC increased the thermal decomposition temperature of ADN@GO@NC by 3.5℃ and reduced its moisture absorption rate by 91.54 % compared to raw ADN. The critical friction sensibility and critical impact sensibility increased by a factor of 1.35 and 1.57, respectively, compared to raw ADN. Combustion tests incorporating ADN@GO@NC into composite solid propellants (CSPs) showed stable and sustained combustion process with high energy release. CSPs with ADN@GO@NC successfully ignited and maintained stable combustion after 24 h at 60 % relative humidity, indicating improved energy release performance. These findings highlight that the double-coated ADN@GO@NC has excellent anti-moisture absorption effect, mechanical insensitivity, and combustion stability, thereby facilitating the application of ADN oxidizer in CSPs.
研究领域:
材料科学
·
能源化学
·
安全工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2018
·
IF 4.521
Li Cao,Lei Chen,Xiaodong Wu,Rui Ran,Tengfei Xu,Ze Chen,Duan Weng
The CeO 2 /TiO 2 catalyst was prepared by a deposition-precipitation method, which exhibited high low-temperature activity under the fast SCR condition. By using transient reaction analysis (TRA), the steps in the fast SCR, including NO 2 adsorption and decomposition, reaction between nitrates and NO, ammonium nitrate formation and reduction by NO, were investigated. Diffuses reflectance infrared Fourier transform spectroscopy (DRIFTS) experiments, via NO + O 2 or NO + NO 2 adsorption, ammonium species reaction with NO x and NO reaction with NH 4 NO 3 , were designed to identify the roles of NO, NO 2 and NH 3 in fast SCR. Based on L-H mechanism, the NH 4 NO 3 formation played an important role in low-temperature SCR reaction. Compared with the behavior in standard SCR, the higher activity in the presence of NO 2 was ascribed to the faster NH 4 NO 3 formation rate and larger amounts of nitrates/nitrites. This phenomenon provided a basis for developing Ce-based catalysts as SCR catalysts for diesel exhaust aftertreatment.
研究领域:
催化化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2023
·
IF 22.1
Wang Song,Qianni Cheng,Li Han,Jiawei Ji,Yandi Cai,Wei Tan,Jingfang Sun,Changjin Tang,Lin Dong
Manganese oxide-based catalysts exhibit excellent low-temperature denitration efficiency, making them potential candidates for application. Herein, the relationship between reaction stability and phase structure for MnO 2 , Mn 2 O 3 and Mn 3 O 4 was disclosed. The NO conversion for Mn 2 O 3 drastically reduced after 120 h reaction, while minor decline was detected for MnO 2 and Mn 3 O 4 . Based on dedicate qualitative and quantitative analyses on the deposits over catalyst surface, deactivation trigged by ammonium nitrate (AN) deposition was confirmed. Different from penta-coordinated Mn 4+ on MnO 2 (110) and tri-coordinated Mn 2+ , penta-coordinated Mn 4+ on Mn 3 O 4 (101), the unique tetra-coordinated Mn 3+ on Mn 2 O 3 (200) could stabilize the nitrates and make it difficult to be removed via decomposition or reaction and accumulate continuously, which resulted in the significant deactivation. This research could not only unveil the poisoning mechanism of MnO x based catalysts, but also provide new insights into the relationship between the catalytic stability and surface Mn-O microstructure.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2019
·
IF 3.45
Xiaoni Du,Xiaohong Wang,Yang Liu,Peizhong Feng
The hollow spherical MoO 3 photocatalyst was successfully prepared by a facile one-step spray solution combustion synthesis method (SSCS). Ammonium molybdate (AHM) and urea were used as the oxidant and fuel, respectively. The MoO 3 with crystallized orthorhombic phase was detected by the X-ray diffractions. And there were many pores on MoO 3 spherical shells shown in SEM results, created by the infiltration of NO 2 and CO 2 during the reactions. Furthermore, an illustration of the MoO 3 stepwise reaction process was proposed. The MoO 3 photocatalysts showed excellent photocatalytic degradation efficiencies over rhodamine B (RhB) under visible-light irradiation, and M4 sample synthesized at 600 °C with the urea/AHM ratio of 4 showed the highest photocatalytic degradation efficiency (82% within 60 min).
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
·
2025
·
IF 3.1
Cui Yuanlu,Yang Rongjie,Lan Yanhua,Zhai Jinxian
Ammonium dinitramide (ADN), an emerging green oxidizer for rocket propellants, faces application limitations due to its low-temperature thermal decomposition characteristics. This study investigates the impact of a small amount of ammonium nitrate (AN) doped into ADN crystal on the stability of ADN crystal. ADN crystal samples containing AN were prepared by solution evaporation method and solvent-antisolvent method, respectively. The results show that AN and ADN form solid solution crystal by solution evaporation method, while solvent-antisolvent method produces phase-separated AN/ADN mixture. Isothermal thermogravimetric analysis conducted at 318–333 K revealed significant decomposition mass loss (3.2–17.5%) exclusively in solid solution samples, whereas the samples of phase-separated AN/ADN crystals show good thermal stability. Differential scanning calorimetry (DSC), X-ray diffraction (XRD), and ion chromatography (IC) were used to investigate the influence of different forms and contents of AN in ADN samples on the low-temperature thermal decomposition properties of ADN. The kinetic models in different decomposition stages were obtained by isothermal kinetic method. Molecular dynamics simulations revealed the decomposition mechanism that the doping of AN induced the elongation of N–N bonds in the surrounding ADN structure, leading to instability of the ADN structure. These findings provide a theoretical basis for improving the stability of ADN in storage and application. Graphical
研究领域:
材料科学
·
化学工程
·
物理化学
·
推进剂与炸药
✓ 已验证
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2025
·
IF 6.5
Qiangqiang Lu,Yong Kou,Lei Xiao,Jiahao Yu,Chong Chen,Jun Di,Guigao Liu,Wei Jiang,Gazi Hao
The energetic ammonium salts represent a class of oxidizer materials that are extensively utilized in contemporary propellant systems. However, the catalytic pyrolysis mechanisms of these salts remain inadequately explored, hindering the efficient application of new energetic ammonium salts. In this study, taking typical energetic ammonium salts (ammonium perchlorate (AP), ammonium nitrate (AN) and ammonium dinitramide (ADN)) as examples, their pyrolysis on the surface of the prepared Fe single-atom catalysts and the combustion flames of the powders were investigated. We learned that Fe single-atoms can promote the pyrolysis and enhance the flame intensity of ammonium salts. The mechanism of Fe single-atom catalyzed ammonium salts has been investigated through density-functional-theory (DFT) calculations, and the results well explained the experimental phenomena. The AP molecule produces oxygen most readily, primarily through the pyrolysis of *ClO 4 (−3.70 eV). The idea of solving the heat-absorbing decomposition of AN is proposed to catalyze its complete decomposition and to avoid the production of NO. The low decomposition temperature of ADN is due to the five major pyrolysis pathways of the molecule and the presence of self-catalytic intermediates. This paper offers guidelines for comprehending the pyrolysis and combustion mechanisms of energetic ammonium salts.
研究领域:
化学推进剂
·
催化
·
材料科学
·
物理化学
·
燃烧
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）