AFRL-AFOSR-VA-TR-2016-0302 Heterogeneously Catalyzed Endothermic Fuel Cracking

The objective of this project was to develop and apply fundamentally based experimental andcomputational methodologies that can lead to the design of improved supercritical fuel/catalyst/heatexchanger systems for cooling hypersonic vehicles. This project was a multi-team effort involvingresearchers at the University of Delaware, United Technologies Research Center, and the ColoradoSchool of Mines. Advances in catalytic studies include:• Developed and applied modeling and software tools to high-pressure chemically reacting processes,including supercritical behavior.• Developed models to evaluate the influence of low levels of steam addition for reducing the production ofpolyaromatics and mitigating catalyst-fouling carbon deposits.• Developed new microstructural models to represent catalytic performance in washcoated monolithstructures.• Measured impact of Pt-exchanged H-ZSM-5 on heptane conversion and selectivity.DISTRIBUTION A: Distribution approved for public release. • Mesured impact of cesium ion exchange for protons in Pt/H-ZSM-5 catalysts. • Carried out high-pressure kinetic studies of hydrocarbon cracking reactions over MoCx nanoparticles supported on non-Acidic Zeolites, specifically [B]ZSM-5 zeolites. • Conducted fundamental investigations of the catalysts using kinetic studies of methane activation, X-rayabsorption spectroscopy and transmission electron microscopy.• Designed aluminosilicate zeolite-based catalyst model systems using combined experimental−theoreticalmethodologies.• Performed specially tailored real-time spectroscopic catalytic reactor studies with n-pentane and n-heptane.• Applied density functional calculations to characterize catalyst model systems with varying Si/Al ratios. Advances in high-pressure gas phase pyrolysis include:• Measured ethane, pentane and hexane pyrolysis over range of pressures, temperatures and residencetimes• Comparisons of conversion, major product distributions and molecular weight growth processes todetailed kinetic mechanisms demonstrate that mechanism can properly account for wide variations in pressure, including supercritical pressures. Successfully tested candidate catalysts under supercritical fuel conditions in UTRC Heat Exchanger rig. Distribution Statement This is block 12 on the SF298 form. Distribution A Approved for Public Release Explanation for Distribution Statement If this is not approved for public release, please provide a short explanation. E.g., contains proprietary information.