Direct Oxidative Nitrogen Fixation from Air and H2O by a Water Falling Film Dielectric Barrier Discharge Reactor at Ambient Pressure and Temperature

Current industrial production of HNO3 relies on the Ostwald process via catalytic oxidation of NH3 , which is responsible for the vast bulk of CO2 emission. An attractive alternative route to HNO3 is direct N2 oxidation to aqueous HNO3 , which avoids the NH3 intermediate. Herein, we for the first time report a non-thermal plasma-assisted nitrogen fixation process characteristic of a large gas-liquid contact based on the water falling film dielectric barrier discharge, wherein HNO3 is produced directly from ambient air and H2 O at atmospheric pressure and room temperature without the presence of any catalytic material. By optimizing the plasma reaction conditions, a relatively high synthesis rate and low energy consumption was achieved at the same time with good product selectivity.