Greenhouse gas conversion to fuels via plasma-enhanced catalysis: Effect of catalyst formulation on electric field and product selectivit

Methane and carbon dioxide are greenhouse gases that are key contributors to climate change. Methane is the primary component of natural gas and is emitted from various sources such as oil and gas wells and landfills, which are often flared. Carbon capture and sequestration are rapidly-advancing technologies to trap carbon dioxide geologically. Another option would be converting them to higher hydrocarbons (C₂+ species), either olefins or paraffins, for use as chemical precursors or fuels. Carbon dioxide hydrogenation or methane reforming can be accomplished using catalysts such as iron or cobalt; the traditional thermal catalysis is an energy-intensive process requiring high temperatures and pressures. Introduction of plasma, called plasma-enhanced catalysis, allows the process to proceed at atmospheric-pressure and ambient temperatures. It is well-known that plasma and catalysts exhibit synergistic interactions that are still not fully understood, but one aspect is that electric fields may influence the electron energy distribution and hence the chemistry, suggesting a route to control product selectivity. We are investigating the influence of dielectric support materials and catalyst formulation in a packed-bed dielectric barrier discharge for production of propane and butane. Here we report results from Electric Field Induced Second Harmonic (E-FISH) generation measurements in plasma-catalyst interactions, as well as product distribution from gas chromatography.