轻金属硼氢化合物在燃烧剂中的应用基础研究

In this proposal, light metal borohydrides, which are often investigated as high-capacity hydrogen-storage materials, are proposed to be adopted as novel combustion agents for solid propellants. The hydrogen and boron-metal composites formed in-situ during the thermal decomposition processes of borohydrides would contribute to the improvement in energy preformances and combustion properties of propellant. The basic scientific issues related with the application of light-metal borohydrides as combustion agents will be studied. Firstly, the decomposition mechanisms and hydrogen-release behaviors of light-metal borohydrides under the conditions for propellant combustion will be evaluated, thus building theoretical foundation for their applications as combustion agents. Secondly, investigations on the interactions between borohydrides and oxidizing components ofsolid propellants will be conducted to resolve the critical compatibility issues and further understand the reactions occur during propellant combustion. Thirdly, in order to obtain guidance for selecting light-metal borohydrides with favorable combustion properties, researches on factors influencing their combustion properties will also be conducted. Results of this project would provide us with theoretical guidance for developing novel borohydride-based combustion agents and promote the development of solid propellant for our country.

本项目提出以高容量储氢材料—轻金属硼氢化合物作为固体推进剂中的新型燃烧剂，利用其受热分解所原位生成的大量氢气和硼-金属复合物改善推进剂的能量水平和燃烧性能。项目针对轻金属硼氢化合物燃烧剂所涉及的基础科学问题进行研究，通过研究其在推进剂工作条件下的分解放氢机理，为其应用奠定理论基础；通过研究其与推进剂中氧化性组分间的相互作用，解决应用中的关键相容性问题并更深入的认识推进剂燃烧过程中二者间的反应；通过阐明影响轻金属硼氢化合物燃烧剂性能的因素，建立轻金属硼氢化合物基燃烧剂的筛选方法。上述研究可为新型硼氢化合物基燃烧剂的研发提供理论依据，推动我国推进剂领域的研究和创新。

本项目开展了轻金属硼氢化合物在固体推进剂中的应用基础研究。合成了Mg(BH4)2、KB3H8和LiB3H8NH3，并获得了其基本物理化学特性；完成了NaBH4、LiBH4、Mg(BH4)2、KB3H8和LiB3H8NH3等轻金属硼氢化合物等的分解放氢机理研究，掌握了金属-硼复合物和氢气生成的规律；完成了NaBH4、LiBH4、Mg(BH4)2等轻金属硼氢化合物燃烧剂与复合推进剂中应用最多的氧化剂高氯酸铵（AP）的相容性研究，发现由于轻金属硼氢化合物对水、氧较为敏感，它们与AP均不相容，受热会发生剧烈的爆燃反应；基于此，研究了KB3H8和LiB3H8NH3等含B3H8-等笼状硼氢离子的轻金属化合物，发现其对水、氧较为不敏感，具有较好的应用前景；利用热力学平衡计算方法研究了影响含轻金属硼氢化合物的推进剂燃烧性能和能量性能的因素，发现推进剂的能量水平则随着硼氢化合物的氢含量增加而升高，燃烧温度与氢含量间则无明显相关关系。