Paul Dababrata, Biswas Souvick, Yeom Hyeonji, Na Kyungsu, Pantoya Michelle L, Kaiser Ralf I
Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, United States.
Department of Chemistry, Chonnam National University, Gwangju 61186, South Korea.
ACS Appl Mater Interfaces. 2024 Oct 9;16(40):53938-53949. doi: 10.1021/acsami.4c12078. Epub 2024 Sep 30.
Nanosheet MFI zeolites (Zeolite Socony Mobil, five) have grown in popularity in cracking catalysis considering their tunability in porous topologies, acidic sites, and sheet thickness, thus allowing them to selectively adsorb molecules of specific sizes, shapes, and polarities, resulting in improved cracking performance for a specific fuel. Five different MFI zeolites in the form of a mesoporous nanosheet structure with a controlled concentration of acidic sites denoted as NSMFI(y), where y is Si/Al ratio, have been synthesized. The effects of the relative acidity content of these NSMFI(y) samples on the zeolite-catalyzed combustion of aluminum nanoparticles (AlNPs)-aided exo-tetrahydrodicyclopentadiene (JP-10) mixed energetic fuel droplets levitated in an oxygen-argon atmosphere were investigated using time-resolved imaging (optical and thermal infrared) and spectroscopic techniques (UV-vis and FTIR). The addition of 1.0 wt % of NSMFI(y) zeolites to AlNPs-JP-10 fluid fuel results in critically reduced ignition delays (9 ± 2 ms), elevated ignition temperatures (2800 ± 170 K), and prolonged burning times (60 ± 10 ms) with an enhanced combustion efficiency. The NSMFI(y) zeolites, which possess high acidity and significant mesoporosity, play a crucial role in improving the combustion efficiency by effectively catalyzing the chemical activation of JP-10 and prolonging the burning of the igniting droplet. The NSMFI (60) variant with the highest acidic site content achieved a maximum combustion efficiency of 80 ± 6%. A comprehensive catalytic combustion mechanism has been elucidated based on the detected reactive intermediates such as hydroxyl radical (OH) and aluminum monoxide (AlO). These findings will help to critically advance the development of next-generation, sustainable, and innovative mixed nanofluid fuels.
纳米片MFI沸石（沸石Socony Mobil，五元）在裂化催化中越来越受欢迎，因为它们在多孔拓扑结构、酸性位点和片层厚度方面具有可调性，从而使它们能够选择性地吸附特定尺寸、形状和极性的分子，从而提高特定燃料的裂化性能。已经合成了五种不同的呈介孔纳米片结构形式的MFI沸石，其酸性位点浓度可控，记为NSMFI(y)，其中y是硅铝比。使用时间分辨成像（光学和热红外）和光谱技术（紫外可见和傅里叶变换红外）研究了这些NSMFI(y)样品的相对酸度含量对在氧氩气氛中悬浮的铝纳米颗粒（AlNP）辅助的外向四氢二环戊二烯（JP-10）混合高能燃料液滴的沸石催化燃烧的影响。向AlNP-JP-10流体燃料中添加1.0 wt%的NSMFI(y)沸石会导致点火延迟显著降低（9±2毫秒）、点火温度升高（2800±170开尔文）以及燃烧时间延长（60±10毫秒），同时燃烧效率提高。具有高酸度和显著介孔率的NSMFI(y)沸石通过有效催化JP-10的化学活化和延长点火液滴的燃烧时间，在提高燃烧效率方面发挥着关键作用。酸性位点含量最高的NSMFI(60)变体实现了80±6%的最大燃烧效率。基于检测到的诸如羟基自由基（OH）和一氧化铝（AlO）等反应中间体，阐明了一种全面的催化燃烧机制。这些发现将有助于极大地推动下一代可持续和创新混合纳米流体燃料的发展。
