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| 題名: | Stabilization and spheroidization of ammonium nitrate: Co-crystallization with crown ethers and spherical crystallization by solvent screening |
| 作者: | 李度;Lee, Tu;Chen, Jeng Wei;Lee, Hung Lin;Lin, Tsung Yan;Tsai, Yee Chen;Cheng, Shao-Liang;Lee, Sheng-Wei;Hu, Jung-Chih;Chen, Lien-Tai |
| 貢獻者: | 工學院化學工程與材料工程學系 |
| 關鍵詞: | acetates;Agglomerates;ambient temperature;Ammonium nitrate;Ammonium nitrates;angle of repose;burning;Burning rate;chemical engineering;chlorine;Co-crystallization;Crown ethers;crystallization;crystals;ethers;explosives;heat;melting point;Methyl alcohol;population density;powders;Precipitation;Propellants;screening;slurries;Smoke;Spheroidization;Spheroidizing |
| 日期: | 2013-06-01 |
| 上傳時間: | 2026-04-21 14:10:49 (UTC+8) |
| 出版者: | Elsevier;Elsevier B.V |
| 摘要: | 摘要： Smoke tests of the purchased Form IV ammonium nitrate (AN) powders at (a) 160°C, (b) 200°C, and (c) 255°C, and 1:1 co-crystals of 1:1 co-crystals of ammonium nitrate–benzo-18-crown-6 (AN–B18C6) at (d) 125°C, (e) 140°C, and (f) 170°C. [Display omitted] •Undesired properties of NH4NO3 were minimized by co-crystal formation.•Spherical crystallization was employed to enhance the flowability of co-crystals.•Co-crystals were smokeless upon heating and exhibited a slower burning rate. Although ammonium nitrate (AN) is a clean burning (chlorine free), non-corrosive, low-hazard, low-flame temperature, inexpensive, easily available energetic material and gives maximum gas horse power per unit weight, propellants incorporating AN suffer from three significant drawbacks: (1) polymorphic (phase) transition near ambient temperature, (2) caking and smoke generation upon burning, and (3) poor flowability for packing. The first two disadvantages could be minimized by forming non-hygroscopic, smokeless 1:1 co-crystals of ammonium nitrate–benzo-18-crown-6 (1:1 co-crystals of AN–B18C6) with a melting point of 125–129°C, produced from the antisolvent precipitation method based on the systems of: ethanol–methyl-tert-butyl-ether (MTBE), methanol–ethyl acetate and methanol–MTBE. From the smoke test and burning characteristics, 1:1 co-crystals of AN–B18C6 is smokeless upon heating and exhibits a slower burning rate than the one of AN. Therefore, co-crystallization may become a solid-state modification method in the areas of propellants and explosives. The third drawback could further be eliminated by forming spherical agglomerates of 1:1 co-crystals of AN–B18C6 through the addition of water as a bridging liquid into the co-crystal slurry resulted at the end of the antisolvent precipitation method. Spherical agglomerates of 1:1 co-crystals of AN–B18C6 grown from Phase IV AN powders (0.32mmol) and B18C6 crystals (0.32mmol) in 0.64mL methanol+11.6mL MTBE+0.08mL water gave relatively high yield of 87.3%, high population density of 20.6/cm3, high sphericity, of 0.86, high friability of 100 showing a greater strength, and low angle of repose of 25.2° indicating a good flowability.
出版者： Elsevier B.V
出版日期： 2013-06-01
出處： Chemical engineering journal (Lausanne, Switzerland : 1996), 2013-06, Vol.225, p.809-817
版權： 2013 Elsevier B.V.
識別號： ISSN: 1385-8947
識別號： EISSN: 1873-3212
識別號： DOI: 10.1016/j.cej.2013.04.002 |
| 顯示於類別: | [化學工程與材料工程學系 ] 期刊論文
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