Catalytic Natural Gas Upgrading of Low Cost Carbon Resources for Producing Valuable Commodities

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Fast pyrolysis followed by hydrodeoxygenation upgrading is the most popular way to produce bio-oil from biomass. A two-step process can be combined together as hydropyrolysis treatment. This approach usually involves continuous hydrogen flow and high operation pressure (15~100 atm), resulting in significantly increased capital and operational costs. Compared to hydrogen, which is not naturally available and thus costly, methane can be readily obtained as natural gas. If methane can be employed as the reducing agent instead of hydrogen to remove oxygen from biomass while saturating the obtained liquid hydrocarbons at near atmospheric pressure (< 3 atm) and moderate temperatures (400~500°C), the produced bio-oil will become more cost competitive. Moreover, methane itself will be converted to higher hydrocarbons beneficial for extra liquid fuel production along with lower carbon dioxide (CO2) emissions from the upgrading process. The generated biomass char is conventionally discharged and delivered to separate equipment for syngas production or power generation from combustion. Unlike the separate char processing route, the proposed research will use a single step to simultaneously convert char and volatile matter from biomass pyrolysis to syngas and liquid fuel, during which the char is gasified by water vapour or CO2 generated from the methane deoxygenation of volatile matter under the facilitation of an added gasification catalyst. In addition to biomass, other low-cost carbon sources, such as low-rank coal and organic municipal and agricultural solid wastes, will be employed as feedstock for oil production with improved quality. The proposed research aims to develop a series of low-cost catalyst candidates and an integrated process that can effectively convert natural gas and low-cost carbon resources simultaneously in one step to valuable commodities, including synthetic crude oil, syngas stream for liquid chemical or fuel production, and high-quality bio-char useful as sorbent for the cleanup of pollutants and fuel for power generation. The synergistic effect occurring between natural gas and co-existing volatile matter generated from biomass pyrolysis will facilitate methane activation and subsequent bio-oil upgrading with the use of a specially tailored catalyst developed through this proposed research program. Any breakthrough achieved from this research will allow for fundamental reforms in the field of energy and will change the way people view fossil fuel energy. Compared to coal and oil, natural gas is a much cleaner fossil fuel source, releasing less nitrogen oxides and CO2 into the atmosphere during combustion. Moreover, if an effective and economical strategy is identified through the proposed study, the low cost and massive reserves of natural gas will allow for its wide application in the future as a primary energy carrier for powering the world. Furthermore, the employment of renewable energy resources, such as biomass and organic solid wastes, in this proposed novel process will keep Canada as a leader of innovations in the clean energy field and provide environmental benefits through reduced greenhouse gas emissions and landfilled wastes.