Christopher Torres

Identification and Characterization of Metal Oxide Catalysts with High Activity, Selectivity, and Regenerability for Selective Hydrogen Combustion in Chemical Looping Applications

Selective hydrogen combustion (SHC) is an effective reaction approach that can improve chemical production yields, reduce energy consumption, and decrease CO2 emissions when combined with previous chemical production processes. SHC describes catalytic combustion where hydrogen can be selectively burned off in a group of combustible components. To undergo SHC, the catalyst must be selective towards hydrogen through its chemical and physical structure. Metal oxide catalysts that are effective SHC catalysts for different hydrocarbon mixtures were identified and characterized. Catalyst performance was determined by the rate at which hydrogen is consumed relative to the hydrocarbon mixture using a micro-reactor and gas chromatography sampling to monitor the reaction over time. Characterization of the catalyst was conducted using X-ray diffraction (XRD) to obtain the bulk crystal structure and scanning electron microscopy (SEM) to view the microscopic structure of the catalyst before and post reaction. Certain metal oxides such as bismuth oxide (Bi2O3) were shown to be an effective SHC catalyst for different hydrocarbon mixtures such as propane and propylene, where propylene was shown to be selectively combusted. Metal oxides such as Bi2O3 were then confirmed to be effective catalysts for selective hydrogen combustion. Different catalysts and hydrocarbon mixtures will be further studied to identify a wider range of SHC systems and applications.