A single step methane conversion into synthetic fuels using microplasma reactor

Direct conversion of natural gas into synthetic fuels such as methanol attracts keen attention because direct process can reduce capital and operating costs of high temperature, energy intensive, multi-step processes. We report a direct and selective synthesis of organic oxygenates such as methanol, formaldehyde, and formic acid via methane partial oxidation at room temperature using non-thermal discharge microreactor. Heat generated by methane partial oxidation is removed efficiently in the microreactor configuration: liquid components are condensed on the reactor wall and separated from O2-rich reactive plasma, enabling selective synthesis of oxygenates while high methane conversion is achieved in a single reactor. As a result, organic oxygenates were synthesized with one-pass yield of 5–20% with 70–30% selectivity. In addition to oxygenates, syngas was produced with selectivity of 40% and H2/CO = 1. Assuming one step catalytic DME synthesis as a post-discharge process, one-pass liquid yield of 30% with 80% selectivity is feasible

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