Sun Dashan, Dai Qiqiang, Chai Wai Siong, Fang Wenjun, Meng Hua
School of Aeronautics and Astronautics, Zhejiang University, Hangzhou, Zhejiang 310027, China.
School of Mechanical Engineering and Automation, Harbin Institute of Technology, Shenzhen, Guangdong 518055, China.
ACS Omega. 2022 May 20;7(22):18521-18530. doi: 10.1021/acsomega.2c01183. eCollection 2022 Jun 7.
The green propellant hydroxylammonium nitrate (HAN) is a good alternative to the conventional propellants in space propulsion applications because of its low toxicity and high energy density. Electrolytic decomposition and ignition of HAN solution, an ionic liquid, is a promising approach. In this work, comprehensive experimental studies were conducted to examine effects of different electrolytic voltages, electrode surface areas, and HAN concentrations on the decomposition process. In the test cases, an optimum electrolytic voltage appears to exist, which leads to the fastest decomposition process. As the voltage increases, a larger electrode surface area on the anode side should be used to overcome an anodic inhibition phenomenon and accelerate the electrolytic process. A high concentration of HAN solution is preferred for its decomposition and ignition. Results also reveal that the electrolytic process of a HAN solution could eventually trigger thermal decomposition reactions, raising the maximum temperature to around 550 K at the final stage. A detailed chemical reaction mechanism was proposed, based on the experimental data and FTIR spectra analyses. Results obtained herein would provide fundamental understandings on the complex electrochemical and physical processes and should be helpful for future applications of the electrolytic decomposition and ignition technology.
绿色推进剂硝酸羟胺（HAN）由于其低毒性和高能量密度，在空间推进应用中是传统推进剂的良好替代品。离子液体HAN溶液的电解分解和点火是一种很有前景的方法。在这项工作中，进行了全面的实验研究，以考察不同电解电压、电极表面积和HAN浓度对分解过程的影响。在测试案例中，似乎存在一个最佳电解电压，它能导致最快的分解过程。随着电压的增加，应在阳极侧使用更大的电极表面积，以克服阳极抑制现象并加速电解过程。高浓度的HAN溶液有利于其分解和点火。结果还表明，HAN溶液的电解过程最终可能引发热分解反应，在最后阶段将最高温度升至约550K。基于实验数据和傅里叶变换红外光谱分析，提出了详细的化学反应机理。本文获得的结果将为复杂的电化学和物理过程提供基本认识，并应有助于电解分解和点火技术的未来应用。
