Molecular Catalysis ( IF 3.9 ) Pub Date : 2020-02-28 , DOI: 10.1016/j.mcat.2020.110851 Ruchika Agnihotri , Charlie Oommen
Monopropellant thruster technology is at the cusp of revival with new age ionic liquids which are safe, less toxic and high performing emerging as substitutes for traditionally used hydrazine. One such promising candidate is Hydroxylammonium nitrate (HAN). Current study explores an iridium metal impregnated bifunctional variant of an earlier developed doped cerium oxide catalyst for HAN decomposition. The performance of bifunctional catalyst was compared against unsupported cerium oxide catalyst and conventional iridium over gamma alumina catalyst. Thermal analysis was the primary test used for performance evaluation and was subsequently followed up in a batch reactor to evaluate the durability of the catalyst to extreme high temperature exposure. Characterization of catalyst before and after decomposition reaction was comprehensively conducted using surface area analysis, SEM/EDS, XRD and XPS. Results did suggest promotional effect of iridium over doped ceria support as demonstrated through increased pressure build-up and rate of pressure-rise.
中文翻译:
推进器应用双功能催化剂评估硝酸羟基铵(HAN)的分解
单推进剂推进器技术正处于复兴的风口浪尖,新时代的离子液体可以替代传统使用的肼,安全,毒性小,高性能。一种这样的有希望的候选者是硝酸羟铵(HAN)。当前的研究探索了一种较早开发的用于HAN分解的掺杂二氧化铈催化剂的铱金属浸渍双功能变体。比较了双功能催化剂与无载体氧化铈催化剂和常规铱/γ-氧化铝催化剂的性能。热分析是用于性能评估的主要测试,随后在间歇反应器中进行后续操作,以评估催化剂对极端高温的耐久性。使用表面积分析,SEM / EDS,XRD和XPS对分解反应前后的催化剂进行了全面表征。结果确实表明了铱对掺杂二氧化铈载体的促进作用,如增加的压力累积和压力上升速率所证明。