Browsing by Author "Jarvis, Jack"

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    Catalytic Aromatization of Paraffin-Rich Oil under Methane Environment
    (2018-09) Jarvis, Jack; Song, Hua; Chen, Zhangxing; Park, Simon S.
    Naphtha fractions obtained from petroleum refinement contain an abundant mixture of hydrocarbons including paraffins, naphthenes, aromatics, and even olefins. n-paraffins are the largest constituents of such oils and are the most undesirable because of their poor octane values and low economic value as chemical feeds. Thus, scientific research aims to convert these components into more valuable components with higher octane numbers for fuels and/or high value chemical precursors used for chemical synthesis. Current naphtha reforming processes require an element of hydrocracking to reduce the number of larger carbon number components but hydrogen is expensive to obtain through the current process of steam reforming natural gas and so an alternative source of hydrogen is also desirable. One such source of hydrogen is methane, a naturally, occurring, and cheap alternative. However, the activation of methane, the most stable of the hydrocarbons, is difficult to achieve. This research aims at the conversion of naphtha feeds (rich in n-paraffins) to more valuable benzene, toluene, and xylenes (BTX) whilst using methane as a hydrogen source through heterogenous catalysis. Catalysts are screened to gauge those with the highest performance and then the effect of methane is also probed. This approach was conducted for two different fractions of naphtha as provided by the petrochemical industry with very different components. A model compound study was also conducted to enable a more comprehensive understanding of the processes involved during upgrading.
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    Catalytic Conversion of Hydrocarbons to Valuable Chemicals and Methanotreating of Oxygenates to Fuel
    (2023-05-02) Jarvis, Jack; Song, Hua; Chen, Zhangxing; Hu, Jinguang
    The world is accelerating towards a gasoline fuel-free future and research focus is shifting towards alternative energy. The efficient use of remaining downstream fossil-fuel derived oil sources and effective treatment of renewable fuel sources has become imperative. Remaining fossil fuel sources like crude oil distillation and Fischer Tropsch products, which contain large amounts of n-paraffins, are no longer desirable as fuels because of their negative environmental impact. As such, they need to be valorized to valuable chemicals instead. This issue is addressed in this thesis by a thorough investigation of numerous hydrocarbons which can be found in such sources, including olefins, paraffins, and naphthenes. Their valorization to aromatics by heterogenous catalysis are investigated to provide a solution and use for remaining hydrocarbons derived from fossil fuels. Additionally, this thesis focuses on the treatment of bio-oils, a suitable fuel source replacement for fossil fuel-based fuels. Bio-oils can come from various sources, but they all have the same issue; they are high in oxygen content. This means energy density is low, acidity is high, and that the oil is thermochemically unstable. Hydrotreating is currently used to deoxygenate these feedstocks as it contributes to decarbonylation, decarboxylation, and saturation reactions. However, hydrogen is expensive, unavailable naturally, and environmentally unfriendly to synthesize as it is obtained predominantly from steam methane reforming. Direct use of methane for the deoxygenation of bio-oils (methanotreating) is investigated in this research. With carefully tailored catalysts, methane can be activated at low temperatures and pressures to provide hydrogen directly and contribute its carbon moiety to oxygen containing components in the product, highlighting the potential for methanotreating in the future of renewable fuels.