Aerosol-based multihollow surface DBD: a promising approach for nitrogen fixation

Abstract

Nonthermal plasma reactors, which enable electrical discharges to be generated in various gases and both liquid and gaseous water, have attracted considerable attention as an alternative method for producing ammonia and fixing nitrogen. In this work, we investigated the basic performance of multihollow surface dielectric barrier discharge (MSDBD) to generate plasma in synthetic air and nitrogen-containing admixtures of water aerosols. The MSDBD in combination with the aerosol stream represents a rather complex geometry for generating the discharge; the plasma is significantly affected by the physicochemical properties of water aerosols on the one hand, on the other hand, this system facilitates the solvation of gaseous plasma products in water and the production of plasma-activated nitrogen-rich water (PAW). The plasma interaction with the water aerosols was studied using optical emission spectroscopy and a scanning mobility particle sizer to provide information about the size and distribution of the water particles entering and exiting the plasma reactor. The gas exiting the plasma reactor was analyzed using Fourier-transform infrared spectroscopy, and the PAW collected in an ice-cooled vessel was analyzed for nitrates (NO2−), nitrites (NO3−), and ammonia (NH3). MSDBD shows promise as a catalyst- and H2-free method for fixing nitrogen in water. Additionally, given the low energy consumption (<5 W) of MSDBD and the straightforward construction of the plasma unit, the suggested approach for PAW production offers a viable route for advancing a decentralized sustainable economy.