Microwave-Fluidized Catalytic Reactor for the Direct Conversion of Methane to Higher Hydrocarbons

Over the past decade, the growth of unconventional oil and gas has resulted in discovery and availability of vast quantities of natural gas across the United States. In many regions, lack or deficit of adequate infrastructure results in gas being stranded, or, in case of oil-associated gas, wastefully vented or flared, needlessly contributing to GHG emissions and global warming. Although manufacturing sector as a whole benefitted from lower energy costs, the effect on the chemical industry remained relatively small. The chemical industry is one of the largest energy-consuming sub-sectors of the manufacturing industry in the U.S. The bulk of the energy consumption and corresponding GHG emissions (as much as 2% of GHG emissions worldwide) is associated with production of many intermediate compounds, such as ethylene, which are used as the basis for a wide range of other chemicals and many industrial and consumer products. Low-cost unconventional gas has enabled use of ethane, a cheaper ethylene feedstock, which accounts for 3%-5% (10% in associated gas) of the natural gas stream. However, energy consumption is not altered, while the bulk of natural gas stream, methane, remains underutilized by the chemical industry. Practical and cost-effective technologies for conversion of methane into petrochemicals, liquid fuels, and materials in distributed, small-scale, low-cost plants with reduced or eliminated greenhouse gas footprint, have the potential to materially change the structure of the chemical industry and significantly reduce its greenhouse footprint. It’s proposed that fluidized catalytic bed of carbon and/or metal-based catalysts can be used to facilitate the rapid and selective conversion of methane to ethylene with a thermal efficiency >65%. The proposed study will develop a proof-of-concept microwave-enhanced catalytic fluidized bed reactor to facilitate the non-equilibrium plasma activation of methane. This reactor will be used to evaluate the selectivity and efficiency of direct methane conversion over various catalytic materials and the role of mild oxidants as a means to improve the stability of methane conversion to ethylene. Experimental testing combined with plasma diagnostics will enable Phase II development of a refined and industrially representative microwave fluidized bed reactor for the direct and efficient conversion of methane to value-added chemicals. Phases I and II will lead to subsequent deployment of a demonstration 1-3 ton/day pilot ethylene conversion plant within the next 2-4 years, and an industrial 60,000 ton/year ethylene conversion plant within 7 years.